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Annotation of src/lib/libc/stdlib/jemalloc.c, Revision 1.19.12.1

1.19.12.1! matt        1: /*     $NetBSD: jemalloc.c,v 1.19.4.1 2010/03/13 00:53:32 riz Exp $    */
1.2       ad          2:
1.1       ad          3: /*-
                      4:  * Copyright (C) 2006,2007 Jason Evans <jasone@FreeBSD.org>.
                      5:  * All rights reserved.
                      6:  *
                      7:  * Redistribution and use in source and binary forms, with or without
                      8:  * modification, are permitted provided that the following conditions
                      9:  * are met:
                     10:  * 1. Redistributions of source code must retain the above copyright
                     11:  *    notice(s), this list of conditions and the following disclaimer as
                     12:  *    the first lines of this file unmodified other than the possible
                     13:  *    addition of one or more copyright notices.
                     14:  * 2. Redistributions in binary form must reproduce the above copyright
                     15:  *    notice(s), this list of conditions and the following disclaimer in
                     16:  *    the documentation and/or other materials provided with the
                     17:  *    distribution.
                     18:  *
                     19:  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
                     20:  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
                     21:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
                     22:  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
                     23:  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
                     24:  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
                     25:  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
                     26:  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
                     27:  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
                     28:  * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
                     29:  * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
                     30:  *
                     31:  *******************************************************************************
                     32:  *
                     33:  * This allocator implementation is designed to provide scalable performance
                     34:  * for multi-threaded programs on multi-processor systems.  The following
                     35:  * features are included for this purpose:
                     36:  *
                     37:  *   + Multiple arenas are used if there are multiple CPUs, which reduces lock
                     38:  *     contention and cache sloshing.
                     39:  *
                     40:  *   + Cache line sharing between arenas is avoided for internal data
                     41:  *     structures.
                     42:  *
                     43:  *   + Memory is managed in chunks and runs (chunks can be split into runs),
                     44:  *     rather than as individual pages.  This provides a constant-time
                     45:  *     mechanism for associating allocations with particular arenas.
                     46:  *
                     47:  * Allocation requests are rounded up to the nearest size class, and no record
                     48:  * of the original request size is maintained.  Allocations are broken into
                     49:  * categories according to size class.  Assuming runtime defaults, 4 kB pages
                     50:  * and a 16 byte quantum, the size classes in each category are as follows:
                     51:  *
                     52:  *   |=====================================|
                     53:  *   | Category | Subcategory    |    Size |
                     54:  *   |=====================================|
                     55:  *   | Small    | Tiny           |       2 |
                     56:  *   |          |                |       4 |
                     57:  *   |          |                |       8 |
                     58:  *   |          |----------------+---------|
                     59:  *   |          | Quantum-spaced |      16 |
                     60:  *   |          |                |      32 |
                     61:  *   |          |                |      48 |
                     62:  *   |          |                |     ... |
                     63:  *   |          |                |     480 |
                     64:  *   |          |                |     496 |
                     65:  *   |          |                |     512 |
                     66:  *   |          |----------------+---------|
                     67:  *   |          | Sub-page       |    1 kB |
                     68:  *   |          |                |    2 kB |
                     69:  *   |=====================================|
                     70:  *   | Large                     |    4 kB |
                     71:  *   |                           |    8 kB |
                     72:  *   |                           |   12 kB |
                     73:  *   |                           |     ... |
                     74:  *   |                           | 1012 kB |
                     75:  *   |                           | 1016 kB |
                     76:  *   |                           | 1020 kB |
                     77:  *   |=====================================|
                     78:  *   | Huge                      |    1 MB |
                     79:  *   |                           |    2 MB |
                     80:  *   |                           |    3 MB |
                     81:  *   |                           |     ... |
                     82:  *   |=====================================|
                     83:  *
                     84:  * A different mechanism is used for each category:
                     85:  *
                     86:  *   Small : Each size class is segregated into its own set of runs.  Each run
                     87:  *           maintains a bitmap of which regions are free/allocated.
                     88:  *
                     89:  *   Large : Each allocation is backed by a dedicated run.  Metadata are stored
                     90:  *           in the associated arena chunk header maps.
                     91:  *
                     92:  *   Huge : Each allocation is backed by a dedicated contiguous set of chunks.
                     93:  *          Metadata are stored in a separate red-black tree.
                     94:  *
                     95:  *******************************************************************************
                     96:  */
                     97:
1.2       ad         98: /* LINTLIBRARY */
                     99:
                    100: #ifdef __NetBSD__
                    101: #  define xutrace(a, b)                utrace("malloc", (a), (b))
                    102: #  define __DECONST(x, y)      ((x)__UNCONST(y))
                    103: #  define NO_TLS
                    104: #else
                    105: #  define xutrace(a, b)                utrace((a), (b))
                    106: #endif /* __NetBSD__ */
                    107:
1.1       ad        108: /*
                    109:  * MALLOC_PRODUCTION disables assertions and statistics gathering.  It also
                    110:  * defaults the A and J runtime options to off.  These settings are appropriate
                    111:  * for production systems.
                    112:  */
1.2       ad        113: #define MALLOC_PRODUCTION
1.1       ad        114:
                    115: #ifndef MALLOC_PRODUCTION
                    116: #  define MALLOC_DEBUG
                    117: #endif
                    118:
                    119: #include <sys/cdefs.h>
1.2       ad        120: /* __FBSDID("$FreeBSD: src/lib/libc/stdlib/malloc.c,v 1.147 2007/06/15 22:00:16 jasone Exp $"); */
1.19.12.1! matt      121: __RCSID("$NetBSD: jemalloc.c,v 1.19.4.1 2010/03/13 00:53:32 riz Exp $");
1.1       ad        122:
1.2       ad        123: #ifdef __FreeBSD__
1.1       ad        124: #include "libc_private.h"
                    125: #ifdef MALLOC_DEBUG
                    126: #  define _LOCK_DEBUG
                    127: #endif
                    128: #include "spinlock.h"
1.2       ad        129: #endif
1.1       ad        130: #include "namespace.h"
                    131: #include <sys/mman.h>
                    132: #include <sys/param.h>
1.2       ad        133: #ifdef __FreeBSD__
1.1       ad        134: #include <sys/stddef.h>
1.2       ad        135: #endif
1.1       ad        136: #include <sys/time.h>
                    137: #include <sys/types.h>
                    138: #include <sys/sysctl.h>
                    139: #include <sys/tree.h>
                    140: #include <sys/uio.h>
                    141: #include <sys/ktrace.h> /* Must come after several other sys/ includes. */
                    142:
1.2       ad        143: #ifdef __FreeBSD__
1.1       ad        144: #include <machine/atomic.h>
                    145: #include <machine/cpufunc.h>
1.2       ad        146: #endif
1.1       ad        147: #include <machine/vmparam.h>
                    148:
                    149: #include <errno.h>
                    150: #include <limits.h>
                    151: #include <pthread.h>
                    152: #include <sched.h>
                    153: #include <stdarg.h>
                    154: #include <stdbool.h>
                    155: #include <stdio.h>
                    156: #include <stdint.h>
                    157: #include <stdlib.h>
                    158: #include <string.h>
                    159: #include <strings.h>
                    160: #include <unistd.h>
                    161:
1.2       ad        162: #ifdef __NetBSD__
                    163: #  include <reentrant.h>
1.16      christos  164: #  include "extern.h"
                    165:
                    166: #define STRERROR_R(a, b, c)    __strerror_r(a, b, c);
                    167: /*
                    168:  * A non localized version of strerror, that avoids bringing in
                    169:  * stdio and the locale code. All the malloc messages are in English
                    170:  * so why bother?
                    171:  */
                    172: static int
                    173: __strerror_r(int e, char *s, size_t l)
                    174: {
                    175:        int rval;
                    176:        size_t slen;
                    177:
                    178:        if (e >= 0 && e < sys_nerr) {
                    179:                slen = strlcpy(s, sys_errlist[e], l);
                    180:                rval = 0;
                    181:        } else {
                    182:                slen = snprintf_ss(s, l, "Unknown error %u", e);
                    183:                rval = EINVAL;
                    184:        }
                    185:        return slen >= l ? ERANGE : rval;
                    186: }
1.2       ad        187: #endif
                    188:
                    189: #ifdef __FreeBSD__
1.16      christos  190: #define STRERROR_R(a, b, c)    strerror_r(a, b, c);
1.1       ad        191: #include "un-namespace.h"
1.2       ad        192: #endif
1.1       ad        193:
                    194: /* MALLOC_STATS enables statistics calculation. */
                    195: #ifndef MALLOC_PRODUCTION
                    196: #  define MALLOC_STATS
                    197: #endif
                    198:
                    199: #ifdef MALLOC_DEBUG
                    200: #  ifdef NDEBUG
                    201: #    undef NDEBUG
                    202: #  endif
                    203: #else
                    204: #  ifndef NDEBUG
                    205: #    define NDEBUG
                    206: #  endif
                    207: #endif
                    208: #include <assert.h>
                    209:
                    210: #ifdef MALLOC_DEBUG
                    211:    /* Disable inlining to make debugging easier. */
                    212: #  define inline
                    213: #endif
                    214:
                    215: /* Size of stack-allocated buffer passed to strerror_r(). */
                    216: #define        STRERROR_BUF            64
                    217:
                    218: /* Minimum alignment of allocations is 2^QUANTUM_2POW_MIN bytes. */
                    219: #ifdef __i386__
                    220: #  define QUANTUM_2POW_MIN     4
                    221: #  define SIZEOF_PTR_2POW      2
                    222: #  define USE_BRK
                    223: #endif
                    224: #ifdef __ia64__
                    225: #  define QUANTUM_2POW_MIN     4
                    226: #  define SIZEOF_PTR_2POW      3
                    227: #endif
                    228: #ifdef __alpha__
                    229: #  define QUANTUM_2POW_MIN     4
                    230: #  define SIZEOF_PTR_2POW      3
                    231: #  define NO_TLS
                    232: #endif
                    233: #ifdef __sparc64__
                    234: #  define QUANTUM_2POW_MIN     4
                    235: #  define SIZEOF_PTR_2POW      3
                    236: #  define NO_TLS
                    237: #endif
                    238: #ifdef __amd64__
                    239: #  define QUANTUM_2POW_MIN     4
                    240: #  define SIZEOF_PTR_2POW      3
                    241: #endif
                    242: #ifdef __arm__
                    243: #  define QUANTUM_2POW_MIN     3
                    244: #  define SIZEOF_PTR_2POW      2
                    245: #  define USE_BRK
                    246: #  define NO_TLS
                    247: #endif
                    248: #ifdef __powerpc__
                    249: #  define QUANTUM_2POW_MIN     4
                    250: #  define SIZEOF_PTR_2POW      2
                    251: #  define USE_BRK
                    252: #endif
1.3       he        253: #if defined(__sparc__) && !defined(__sparc64__)
1.2       ad        254: #  define QUANTUM_2POW_MIN     4
                    255: #  define SIZEOF_PTR_2POW      2
                    256: #  define USE_BRK
                    257: #endif
                    258: #ifdef __vax__
                    259: #  define QUANTUM_2POW_MIN     4
                    260: #  define SIZEOF_PTR_2POW      2
                    261: #  define USE_BRK
                    262: #endif
                    263: #ifdef __sh__
                    264: #  define QUANTUM_2POW_MIN     4
                    265: #  define SIZEOF_PTR_2POW      2
                    266: #  define USE_BRK
                    267: #endif
                    268: #ifdef __m68k__
                    269: #  define QUANTUM_2POW_MIN     4
                    270: #  define SIZEOF_PTR_2POW      2
                    271: #  define USE_BRK
                    272: #endif
                    273: #ifdef __mips__
                    274: #  define QUANTUM_2POW_MIN     4
                    275: #  define SIZEOF_PTR_2POW      2
                    276: #  define USE_BRK
                    277: #endif
1.4       ad        278: #ifdef __hppa__
                    279: #  define QUANTUM_2POW_MIN     4
                    280: #  define SIZEOF_PTR_2POW      2
                    281: #  define USE_BRK
                    282: #endif
1.1       ad        283:
                    284: #define        SIZEOF_PTR              (1 << SIZEOF_PTR_2POW)
                    285:
                    286: /* sizeof(int) == (1 << SIZEOF_INT_2POW). */
                    287: #ifndef SIZEOF_INT_2POW
                    288: #  define SIZEOF_INT_2POW      2
                    289: #endif
                    290:
                    291: /* We can't use TLS in non-PIC programs, since TLS relies on loader magic. */
                    292: #if (!defined(PIC) && !defined(NO_TLS))
                    293: #  define NO_TLS
                    294: #endif
                    295:
                    296: /*
                    297:  * Size and alignment of memory chunks that are allocated by the OS's virtual
                    298:  * memory system.
                    299:  */
                    300: #define        CHUNK_2POW_DEFAULT      20
                    301:
                    302: /*
                    303:  * Maximum size of L1 cache line.  This is used to avoid cache line aliasing,
                    304:  * so over-estimates are okay (up to a point), but under-estimates will
                    305:  * negatively affect performance.
                    306:  */
                    307: #define        CACHELINE_2POW          6
                    308: #define        CACHELINE               ((size_t)(1 << CACHELINE_2POW))
                    309:
                    310: /* Smallest size class to support. */
                    311: #define        TINY_MIN_2POW           1
                    312:
                    313: /*
                    314:  * Maximum size class that is a multiple of the quantum, but not (necessarily)
                    315:  * a power of 2.  Above this size, allocations are rounded up to the nearest
                    316:  * power of 2.
                    317:  */
                    318: #define        SMALL_MAX_2POW_DEFAULT  9
                    319: #define        SMALL_MAX_DEFAULT       (1 << SMALL_MAX_2POW_DEFAULT)
                    320:
                    321: /*
                    322:  * Maximum desired run header overhead.  Runs are sized as small as possible
                    323:  * such that this setting is still honored, without violating other constraints.
                    324:  * The goal is to make runs as small as possible without exceeding a per run
                    325:  * external fragmentation threshold.
                    326:  *
                    327:  * Note that it is possible to set this low enough that it cannot be honored
                    328:  * for some/all object sizes, since there is one bit of header overhead per
                    329:  * object (plus a constant).  In such cases, this constraint is relaxed.
                    330:  *
                    331:  * RUN_MAX_OVRHD_RELAX specifies the maximum number of bits per region of
                    332:  * overhead for which RUN_MAX_OVRHD is relaxed.
                    333:  */
                    334: #define RUN_MAX_OVRHD          0.015
                    335: #define RUN_MAX_OVRHD_RELAX    1.5
                    336:
                    337: /* Put a cap on small object run size.  This overrides RUN_MAX_OVRHD. */
                    338: #define RUN_MAX_SMALL_2POW     15
                    339: #define RUN_MAX_SMALL          (1 << RUN_MAX_SMALL_2POW)
                    340:
                    341: /******************************************************************************/
                    342:
1.2       ad        343: #ifdef __FreeBSD__
1.1       ad        344: /*
                    345:  * Mutexes based on spinlocks.  We can't use normal pthread mutexes, because
                    346:  * they require malloc()ed memory.
                    347:  */
                    348: typedef struct {
                    349:        spinlock_t      lock;
                    350: } malloc_mutex_t;
                    351:
                    352: /* Set to true once the allocator has been initialized. */
                    353: static bool malloc_initialized = false;
                    354:
                    355: /* Used to avoid initialization races. */
                    356: static malloc_mutex_t init_lock = {_SPINLOCK_INITIALIZER};
1.2       ad        357: #else
                    358: #define        malloc_mutex_t  mutex_t
                    359:
                    360: /* Set to true once the allocator has been initialized. */
                    361: static bool malloc_initialized = false;
                    362:
                    363: /* Used to avoid initialization races. */
                    364: static mutex_t init_lock = MUTEX_INITIALIZER;
                    365: #endif
1.1       ad        366:
                    367: /******************************************************************************/
                    368: /*
                    369:  * Statistics data structures.
                    370:  */
                    371:
                    372: #ifdef MALLOC_STATS
                    373:
                    374: typedef struct malloc_bin_stats_s malloc_bin_stats_t;
                    375: struct malloc_bin_stats_s {
                    376:        /*
                    377:         * Number of allocation requests that corresponded to the size of this
                    378:         * bin.
                    379:         */
                    380:        uint64_t        nrequests;
                    381:
                    382:        /* Total number of runs created for this bin's size class. */
                    383:        uint64_t        nruns;
                    384:
                    385:        /*
                    386:         * Total number of runs reused by extracting them from the runs tree for
                    387:         * this bin's size class.
                    388:         */
                    389:        uint64_t        reruns;
                    390:
                    391:        /* High-water mark for this bin. */
                    392:        unsigned long   highruns;
                    393:
                    394:        /* Current number of runs in this bin. */
                    395:        unsigned long   curruns;
                    396: };
                    397:
                    398: typedef struct arena_stats_s arena_stats_t;
                    399: struct arena_stats_s {
                    400:        /* Number of bytes currently mapped. */
                    401:        size_t          mapped;
                    402:
                    403:        /* Per-size-category statistics. */
                    404:        size_t          allocated_small;
                    405:        uint64_t        nmalloc_small;
                    406:        uint64_t        ndalloc_small;
                    407:
                    408:        size_t          allocated_large;
                    409:        uint64_t        nmalloc_large;
                    410:        uint64_t        ndalloc_large;
                    411: };
                    412:
                    413: typedef struct chunk_stats_s chunk_stats_t;
                    414: struct chunk_stats_s {
                    415:        /* Number of chunks that were allocated. */
                    416:        uint64_t        nchunks;
                    417:
                    418:        /* High-water mark for number of chunks allocated. */
                    419:        unsigned long   highchunks;
                    420:
                    421:        /*
                    422:         * Current number of chunks allocated.  This value isn't maintained for
                    423:         * any other purpose, so keep track of it in order to be able to set
                    424:         * highchunks.
                    425:         */
                    426:        unsigned long   curchunks;
                    427: };
                    428:
                    429: #endif /* #ifdef MALLOC_STATS */
                    430:
                    431: /******************************************************************************/
                    432: /*
                    433:  * Chunk data structures.
                    434:  */
                    435:
                    436: /* Tree of chunks. */
                    437: typedef struct chunk_node_s chunk_node_t;
                    438: struct chunk_node_s {
                    439:        /* Linkage for the chunk tree. */
                    440:        RB_ENTRY(chunk_node_s) link;
                    441:
                    442:        /*
                    443:         * Pointer to the chunk that this tree node is responsible for.  In some
                    444:         * (but certainly not all) cases, this data structure is placed at the
                    445:         * beginning of the corresponding chunk, so this field may point to this
                    446:         * node.
                    447:         */
                    448:        void    *chunk;
                    449:
                    450:        /* Total chunk size. */
                    451:        size_t  size;
                    452: };
                    453: typedef struct chunk_tree_s chunk_tree_t;
                    454: RB_HEAD(chunk_tree_s, chunk_node_s);
                    455:
                    456: /******************************************************************************/
                    457: /*
                    458:  * Arena data structures.
                    459:  */
                    460:
                    461: typedef struct arena_s arena_t;
                    462: typedef struct arena_bin_s arena_bin_t;
                    463:
                    464: typedef struct arena_chunk_map_s arena_chunk_map_t;
                    465: struct arena_chunk_map_s {
                    466:        /* Number of pages in run. */
                    467:        uint32_t        npages;
                    468:        /*
                    469:         * Position within run.  For a free run, this is POS_FREE for the first
                    470:         * and last pages.  The POS_FREE special value makes it possible to
                    471:         * quickly coalesce free runs.
                    472:         *
                    473:         * This is the limiting factor for chunksize; there can be at most 2^31
                    474:         * pages in a run.
                    475:         */
                    476: #define POS_FREE ((uint32_t)0xffffffffU)
                    477:        uint32_t        pos;
                    478: };
                    479:
                    480: /* Arena chunk header. */
                    481: typedef struct arena_chunk_s arena_chunk_t;
                    482: struct arena_chunk_s {
                    483:        /* Arena that owns the chunk. */
                    484:        arena_t *arena;
                    485:
                    486:        /* Linkage for the arena's chunk tree. */
                    487:        RB_ENTRY(arena_chunk_s) link;
                    488:
                    489:        /*
                    490:         * Number of pages in use.  This is maintained in order to make
                    491:         * detection of empty chunks fast.
                    492:         */
                    493:        uint32_t pages_used;
                    494:
                    495:        /*
                    496:         * Every time a free run larger than this value is created/coalesced,
                    497:         * this value is increased.  The only way that the value decreases is if
                    498:         * arena_run_alloc() fails to find a free run as large as advertised by
                    499:         * this value.
                    500:         */
                    501:        uint32_t max_frun_npages;
                    502:
                    503:        /*
                    504:         * Every time a free run that starts at an earlier page than this value
                    505:         * is created/coalesced, this value is decreased.  It is reset in a
                    506:         * similar fashion to max_frun_npages.
                    507:         */
                    508:        uint32_t min_frun_ind;
                    509:
                    510:        /*
                    511:         * Map of pages within chunk that keeps track of free/large/small.  For
                    512:         * free runs, only the map entries for the first and last pages are
                    513:         * kept up to date, so that free runs can be quickly coalesced.
                    514:         */
                    515:        arena_chunk_map_t map[1]; /* Dynamically sized. */
                    516: };
                    517: typedef struct arena_chunk_tree_s arena_chunk_tree_t;
                    518: RB_HEAD(arena_chunk_tree_s, arena_chunk_s);
                    519:
                    520: typedef struct arena_run_s arena_run_t;
                    521: struct arena_run_s {
                    522:        /* Linkage for run trees. */
                    523:        RB_ENTRY(arena_run_s) link;
                    524:
                    525: #ifdef MALLOC_DEBUG
                    526:        uint32_t        magic;
                    527: #  define ARENA_RUN_MAGIC 0x384adf93
                    528: #endif
                    529:
                    530:        /* Bin this run is associated with. */
                    531:        arena_bin_t     *bin;
                    532:
                    533:        /* Index of first element that might have a free region. */
                    534:        unsigned        regs_minelm;
                    535:
                    536:        /* Number of free regions in run. */
                    537:        unsigned        nfree;
                    538:
                    539:        /* Bitmask of in-use regions (0: in use, 1: free). */
                    540:        unsigned        regs_mask[1]; /* Dynamically sized. */
                    541: };
                    542: typedef struct arena_run_tree_s arena_run_tree_t;
                    543: RB_HEAD(arena_run_tree_s, arena_run_s);
                    544:
                    545: struct arena_bin_s {
                    546:        /*
                    547:         * Current run being used to service allocations of this bin's size
                    548:         * class.
                    549:         */
                    550:        arena_run_t     *runcur;
                    551:
                    552:        /*
                    553:         * Tree of non-full runs.  This tree is used when looking for an
                    554:         * existing run when runcur is no longer usable.  We choose the
                    555:         * non-full run that is lowest in memory; this policy tends to keep
                    556:         * objects packed well, and it can also help reduce the number of
                    557:         * almost-empty chunks.
                    558:         */
                    559:        arena_run_tree_t runs;
                    560:
                    561:        /* Size of regions in a run for this bin's size class. */
                    562:        size_t          reg_size;
                    563:
                    564:        /* Total size of a run for this bin's size class. */
                    565:        size_t          run_size;
                    566:
                    567:        /* Total number of regions in a run for this bin's size class. */
                    568:        uint32_t        nregs;
                    569:
                    570:        /* Number of elements in a run's regs_mask for this bin's size class. */
                    571:        uint32_t        regs_mask_nelms;
                    572:
                    573:        /* Offset of first region in a run for this bin's size class. */
                    574:        uint32_t        reg0_offset;
                    575:
                    576: #ifdef MALLOC_STATS
                    577:        /* Bin statistics. */
                    578:        malloc_bin_stats_t stats;
                    579: #endif
                    580: };
                    581:
                    582: struct arena_s {
                    583: #ifdef MALLOC_DEBUG
                    584:        uint32_t                magic;
                    585: #  define ARENA_MAGIC 0x947d3d24
                    586: #endif
                    587:
                    588:        /* All operations on this arena require that mtx be locked. */
                    589:        malloc_mutex_t          mtx;
                    590:
                    591: #ifdef MALLOC_STATS
                    592:        arena_stats_t           stats;
                    593: #endif
                    594:
                    595:        /*
                    596:         * Tree of chunks this arena manages.
                    597:         */
                    598:        arena_chunk_tree_t      chunks;
                    599:
                    600:        /*
                    601:         * In order to avoid rapid chunk allocation/deallocation when an arena
                    602:         * oscillates right on the cusp of needing a new chunk, cache the most
                    603:         * recently freed chunk.  This caching is disabled by opt_hint.
                    604:         *
                    605:         * There is one spare chunk per arena, rather than one spare total, in
                    606:         * order to avoid interactions between multiple threads that could make
                    607:         * a single spare inadequate.
                    608:         */
                    609:        arena_chunk_t *spare;
                    610:
                    611:        /*
                    612:         * bins is used to store rings of free regions of the following sizes,
                    613:         * assuming a 16-byte quantum, 4kB pagesize, and default MALLOC_OPTIONS.
                    614:         *
                    615:         *   bins[i] | size |
                    616:         *   --------+------+
                    617:         *        0  |    2 |
                    618:         *        1  |    4 |
                    619:         *        2  |    8 |
                    620:         *   --------+------+
                    621:         *        3  |   16 |
                    622:         *        4  |   32 |
                    623:         *        5  |   48 |
                    624:         *        6  |   64 |
                    625:         *           :      :
                    626:         *           :      :
                    627:         *       33  |  496 |
                    628:         *       34  |  512 |
                    629:         *   --------+------+
                    630:         *       35  | 1024 |
                    631:         *       36  | 2048 |
                    632:         *   --------+------+
                    633:         */
                    634:        arena_bin_t             bins[1]; /* Dynamically sized. */
                    635: };
                    636:
                    637: /******************************************************************************/
                    638: /*
                    639:  * Data.
                    640:  */
                    641:
                    642: /* Number of CPUs. */
                    643: static unsigned                ncpus;
                    644:
                    645: /* VM page size. */
                    646: static size_t          pagesize;
                    647: static size_t          pagesize_mask;
1.9       christos  648: static int             pagesize_2pow;
1.1       ad        649:
                    650: /* Various bin-related settings. */
                    651: static size_t          bin_maxclass; /* Max size class for bins. */
                    652: static unsigned                ntbins; /* Number of (2^n)-spaced tiny bins. */
                    653: static unsigned                nqbins; /* Number of quantum-spaced bins. */
                    654: static unsigned                nsbins; /* Number of (2^n)-spaced sub-page bins. */
                    655: static size_t          small_min;
                    656: static size_t          small_max;
                    657:
                    658: /* Various quantum-related settings. */
                    659: static size_t          quantum;
                    660: static size_t          quantum_mask; /* (quantum - 1). */
                    661:
                    662: /* Various chunk-related settings. */
                    663: static size_t          chunksize;
                    664: static size_t          chunksize_mask; /* (chunksize - 1). */
1.5       yamt      665: static int             chunksize_2pow;
1.1       ad        666: static unsigned                chunk_npages;
                    667: static unsigned                arena_chunk_header_npages;
                    668: static size_t          arena_maxclass; /* Max size class for arenas. */
                    669:
                    670: /********/
                    671: /*
                    672:  * Chunks.
                    673:  */
                    674:
                    675: /* Protects chunk-related data structures. */
                    676: static malloc_mutex_t  chunks_mtx;
                    677:
                    678: /* Tree of chunks that are stand-alone huge allocations. */
                    679: static chunk_tree_t    huge;
                    680:
                    681: #ifdef USE_BRK
                    682: /*
                    683:  * Try to use brk for chunk-size allocations, due to address space constraints.
                    684:  */
                    685: /*
                    686:  * Protects sbrk() calls.  This must be separate from chunks_mtx, since
                    687:  * base_pages_alloc() also uses sbrk(), but cannot lock chunks_mtx (doing so
                    688:  * could cause recursive lock acquisition).
                    689:  */
                    690: static malloc_mutex_t  brk_mtx;
                    691: /* Result of first sbrk(0) call. */
                    692: static void            *brk_base;
                    693: /* Current end of brk, or ((void *)-1) if brk is exhausted. */
                    694: static void            *brk_prev;
                    695: /* Current upper limit on brk addresses. */
                    696: static void            *brk_max;
                    697: #endif
                    698:
                    699: #ifdef MALLOC_STATS
                    700: /* Huge allocation statistics. */
                    701: static uint64_t                huge_nmalloc;
                    702: static uint64_t                huge_ndalloc;
1.8       yamt      703: static uint64_t                huge_nralloc;
1.1       ad        704: static size_t          huge_allocated;
                    705: #endif
                    706:
                    707: /*
                    708:  * Tree of chunks that were previously allocated.  This is used when allocating
                    709:  * chunks, in an attempt to re-use address space.
                    710:  */
                    711: static chunk_tree_t    old_chunks;
                    712:
                    713: /****************************/
                    714: /*
                    715:  * base (internal allocation).
                    716:  */
                    717:
                    718: /*
                    719:  * Current pages that are being used for internal memory allocations.  These
                    720:  * pages are carved up in cacheline-size quanta, so that there is no chance of
                    721:  * false cache line sharing.
                    722:  */
                    723: static void            *base_pages;
                    724: static void            *base_next_addr;
                    725: static void            *base_past_addr; /* Addr immediately past base_pages. */
                    726: static chunk_node_t    *base_chunk_nodes; /* LIFO cache of chunk nodes. */
                    727: static malloc_mutex_t  base_mtx;
                    728: #ifdef MALLOC_STATS
                    729: static size_t          base_mapped;
                    730: #endif
                    731:
                    732: /********/
                    733: /*
                    734:  * Arenas.
                    735:  */
                    736:
                    737: /*
                    738:  * Arenas that are used to service external requests.  Not all elements of the
                    739:  * arenas array are necessarily used; arenas are created lazily as needed.
                    740:  */
                    741: static arena_t         **arenas;
                    742: static unsigned                narenas;
                    743: static unsigned                next_arena;
                    744: static malloc_mutex_t  arenas_mtx; /* Protects arenas initialization. */
                    745:
1.15      ad        746: #ifndef NO_TLS
                    747: /*
                    748:  * Map of pthread_self() --> arenas[???], used for selecting an arena to use
                    749:  * for allocations.
                    750:  */
                    751: static __thread arena_t        *arenas_map;
                    752: #define        get_arenas_map()        (arenas_map)
                    753: #define        set_arenas_map(x)       (arenas_map = x)
                    754: #else
1.2       ad        755: static thread_key_t arenas_map_key;
1.15      ad        756: #define        get_arenas_map()        thr_getspecific(arenas_map_key)
                    757: #define        set_arenas_map(x)       thr_setspecific(arenas_map_key, x)
                    758: #endif
1.1       ad        759:
                    760: #ifdef MALLOC_STATS
                    761: /* Chunk statistics. */
                    762: static chunk_stats_t   stats_chunks;
                    763: #endif
                    764:
                    765: /*******************************/
                    766: /*
                    767:  * Runtime configuration options.
                    768:  */
                    769: const char     *_malloc_options;
                    770:
                    771: #ifndef MALLOC_PRODUCTION
                    772: static bool    opt_abort = true;
                    773: static bool    opt_junk = true;
                    774: #else
                    775: static bool    opt_abort = false;
                    776: static bool    opt_junk = false;
                    777: #endif
                    778: static bool    opt_hint = false;
                    779: static bool    opt_print_stats = false;
1.9       christos  780: static int     opt_quantum_2pow = QUANTUM_2POW_MIN;
                    781: static int     opt_small_max_2pow = SMALL_MAX_2POW_DEFAULT;
                    782: static int     opt_chunk_2pow = CHUNK_2POW_DEFAULT;
1.1       ad        783: static bool    opt_utrace = false;
                    784: static bool    opt_sysv = false;
                    785: static bool    opt_xmalloc = false;
                    786: static bool    opt_zero = false;
                    787: static int32_t opt_narenas_lshift = 0;
                    788:
                    789: typedef struct {
                    790:        void    *p;
                    791:        size_t  s;
                    792:        void    *r;
                    793: } malloc_utrace_t;
                    794:
                    795: #define        UTRACE(a, b, c)                                                 \
                    796:        if (opt_utrace) {                                               \
1.2       ad        797:                malloc_utrace_t ut;                                     \
                    798:                ut.p = a;                                               \
                    799:                ut.s = b;                                               \
                    800:                ut.r = c;                                               \
                    801:                xutrace(&ut, sizeof(ut));                               \
1.1       ad        802:        }
                    803:
                    804: /******************************************************************************/
                    805: /*
                    806:  * Begin function prototypes for non-inline static functions.
                    807:  */
                    808:
                    809: static void    wrtmessage(const char *p1, const char *p2, const char *p3,
                    810:                const char *p4);
                    811: #ifdef MALLOC_STATS
                    812: static void    malloc_printf(const char *format, ...);
                    813: #endif
                    814: static char    *umax2s(uintmax_t x, char *s);
                    815: static bool    base_pages_alloc(size_t minsize);
                    816: static void    *base_alloc(size_t size);
                    817: static chunk_node_t *base_chunk_node_alloc(void);
                    818: static void    base_chunk_node_dealloc(chunk_node_t *node);
                    819: #ifdef MALLOC_STATS
                    820: static void    stats_print(arena_t *arena);
                    821: #endif
                    822: static void    *pages_map(void *addr, size_t size);
1.5       yamt      823: static void    *pages_map_align(void *addr, size_t size, int align);
1.1       ad        824: static void    pages_unmap(void *addr, size_t size);
                    825: static void    *chunk_alloc(size_t size);
                    826: static void    chunk_dealloc(void *chunk, size_t size);
                    827: static void    arena_run_split(arena_t *arena, arena_run_t *run, size_t size);
                    828: static arena_chunk_t *arena_chunk_alloc(arena_t *arena);
                    829: static void    arena_chunk_dealloc(arena_t *arena, arena_chunk_t *chunk);
                    830: static arena_run_t *arena_run_alloc(arena_t *arena, size_t size);
                    831: static void    arena_run_dalloc(arena_t *arena, arena_run_t *run, size_t size);
                    832: static arena_run_t *arena_bin_nonfull_run_get(arena_t *arena, arena_bin_t *bin);
                    833: static void *arena_bin_malloc_hard(arena_t *arena, arena_bin_t *bin);
                    834: static size_t arena_bin_run_size_calc(arena_bin_t *bin, size_t min_run_size);
                    835: static void    *arena_malloc(arena_t *arena, size_t size);
                    836: static void    *arena_palloc(arena_t *arena, size_t alignment, size_t size,
                    837:     size_t alloc_size);
                    838: static size_t  arena_salloc(const void *ptr);
                    839: static void    *arena_ralloc(void *ptr, size_t size, size_t oldsize);
                    840: static void    arena_dalloc(arena_t *arena, arena_chunk_t *chunk, void *ptr);
                    841: static bool    arena_new(arena_t *arena);
                    842: static arena_t *arenas_extend(unsigned ind);
                    843: static void    *huge_malloc(size_t size);
                    844: static void    *huge_palloc(size_t alignment, size_t size);
                    845: static void    *huge_ralloc(void *ptr, size_t size, size_t oldsize);
                    846: static void    huge_dalloc(void *ptr);
                    847: static void    *imalloc(size_t size);
                    848: static void    *ipalloc(size_t alignment, size_t size);
                    849: static void    *icalloc(size_t size);
                    850: static size_t  isalloc(const void *ptr);
                    851: static void    *iralloc(void *ptr, size_t size);
                    852: static void    idalloc(void *ptr);
                    853: static void    malloc_print_stats(void);
                    854: static bool    malloc_init_hard(void);
                    855:
                    856: /*
                    857:  * End function prototypes.
                    858:  */
                    859: /******************************************************************************/
                    860: /*
                    861:  * Begin mutex.
                    862:  */
                    863:
1.15      ad        864: #ifdef __NetBSD__
1.2       ad        865: #define        malloc_mutex_init(m)    mutex_init(m, NULL)
                    866: #define        malloc_mutex_lock(m)    mutex_lock(m)
                    867: #define        malloc_mutex_unlock(m)  mutex_unlock(m)
1.15      ad        868: #else  /* __NetBSD__ */
                    869: static inline void
                    870: malloc_mutex_init(malloc_mutex_t *a_mutex)
                    871: {
                    872:        static const spinlock_t lock = _SPINLOCK_INITIALIZER;
                    873:
                    874:        a_mutex->lock = lock;
                    875: }
                    876:
                    877: static inline void
                    878: malloc_mutex_lock(malloc_mutex_t *a_mutex)
                    879: {
                    880:
                    881:        if (__isthreaded)
                    882:                _SPINLOCK(&a_mutex->lock);
                    883: }
                    884:
                    885: static inline void
                    886: malloc_mutex_unlock(malloc_mutex_t *a_mutex)
                    887: {
                    888:
                    889:        if (__isthreaded)
                    890:                _SPINUNLOCK(&a_mutex->lock);
                    891: }
                    892: #endif /* __NetBSD__ */
1.1       ad        893:
                    894: /*
                    895:  * End mutex.
                    896:  */
                    897: /******************************************************************************/
                    898: /*
                    899:  * Begin Utility functions/macros.
                    900:  */
                    901:
                    902: /* Return the chunk address for allocation address a. */
                    903: #define        CHUNK_ADDR2BASE(a)                                              \
                    904:        ((void *)((uintptr_t)(a) & ~chunksize_mask))
                    905:
                    906: /* Return the chunk offset of address a. */
                    907: #define        CHUNK_ADDR2OFFSET(a)                                            \
                    908:        ((size_t)((uintptr_t)(a) & chunksize_mask))
                    909:
                    910: /* Return the smallest chunk multiple that is >= s. */
                    911: #define        CHUNK_CEILING(s)                                                \
                    912:        (((s) + chunksize_mask) & ~chunksize_mask)
                    913:
                    914: /* Return the smallest cacheline multiple that is >= s. */
                    915: #define        CACHELINE_CEILING(s)                                            \
                    916:        (((s) + (CACHELINE - 1)) & ~(CACHELINE - 1))
                    917:
                    918: /* Return the smallest quantum multiple that is >= a. */
                    919: #define        QUANTUM_CEILING(a)                                              \
                    920:        (((a) + quantum_mask) & ~quantum_mask)
                    921:
                    922: /* Return the smallest pagesize multiple that is >= s. */
                    923: #define        PAGE_CEILING(s)                                                 \
                    924:        (((s) + pagesize_mask) & ~pagesize_mask)
                    925:
                    926: /* Compute the smallest power of 2 that is >= x. */
                    927: static inline size_t
                    928: pow2_ceil(size_t x)
                    929: {
                    930:
                    931:        x--;
                    932:        x |= x >> 1;
                    933:        x |= x >> 2;
                    934:        x |= x >> 4;
                    935:        x |= x >> 8;
                    936:        x |= x >> 16;
                    937: #if (SIZEOF_PTR == 8)
                    938:        x |= x >> 32;
                    939: #endif
                    940:        x++;
                    941:        return (x);
                    942: }
                    943:
                    944: static void
                    945: wrtmessage(const char *p1, const char *p2, const char *p3, const char *p4)
                    946: {
                    947:
1.16      christos  948:        write(STDERR_FILENO, p1, strlen(p1));
                    949:        write(STDERR_FILENO, p2, strlen(p2));
                    950:        write(STDERR_FILENO, p3, strlen(p3));
                    951:        write(STDERR_FILENO, p4, strlen(p4));
1.1       ad        952: }
                    953:
                    954: void   (*_malloc_message)(const char *p1, const char *p2, const char *p3,
                    955:            const char *p4) = wrtmessage;
                    956:
                    957: #ifdef MALLOC_STATS
                    958: /*
                    959:  * Print to stderr in such a way as to (hopefully) avoid memory allocation.
                    960:  */
                    961: static void
                    962: malloc_printf(const char *format, ...)
                    963: {
                    964:        char buf[4096];
                    965:        va_list ap;
                    966:
                    967:        va_start(ap, format);
                    968:        vsnprintf(buf, sizeof(buf), format, ap);
                    969:        va_end(ap);
                    970:        _malloc_message(buf, "", "", "");
                    971: }
                    972: #endif
                    973:
                    974: /*
                    975:  * We don't want to depend on vsnprintf() for production builds, since that can
                    976:  * cause unnecessary bloat for static binaries.  umax2s() provides minimal
                    977:  * integer printing functionality, so that malloc_printf() use can be limited to
                    978:  * MALLOC_STATS code.
                    979:  */
                    980: #define UMAX2S_BUFSIZE 21
                    981: static char *
                    982: umax2s(uintmax_t x, char *s)
                    983: {
                    984:        unsigned i;
                    985:
                    986:        /* Make sure UMAX2S_BUFSIZE is large enough. */
1.7       yamt      987:        /* LINTED */
1.1       ad        988:        assert(sizeof(uintmax_t) <= 8);
                    989:
                    990:        i = UMAX2S_BUFSIZE - 1;
                    991:        s[i] = '\0';
                    992:        do {
                    993:                i--;
1.2       ad        994:                s[i] = "0123456789"[(int)x % 10];
                    995:                x /= (uintmax_t)10LL;
1.1       ad        996:        } while (x > 0);
                    997:
                    998:        return (&s[i]);
                    999: }
                   1000:
                   1001: /******************************************************************************/
                   1002:
                   1003: static bool
                   1004: base_pages_alloc(size_t minsize)
                   1005: {
1.2       ad       1006:        size_t csize = 0;
1.1       ad       1007:
                   1008: #ifdef USE_BRK
                   1009:        /*
                   1010:         * Do special brk allocation here, since base allocations don't need to
                   1011:         * be chunk-aligned.
                   1012:         */
                   1013:        if (brk_prev != (void *)-1) {
                   1014:                void *brk_cur;
                   1015:                intptr_t incr;
                   1016:
                   1017:                if (minsize != 0)
                   1018:                        csize = CHUNK_CEILING(minsize);
                   1019:
                   1020:                malloc_mutex_lock(&brk_mtx);
                   1021:                do {
                   1022:                        /* Get the current end of brk. */
                   1023:                        brk_cur = sbrk(0);
                   1024:
                   1025:                        /*
                   1026:                         * Calculate how much padding is necessary to
                   1027:                         * chunk-align the end of brk.  Don't worry about
                   1028:                         * brk_cur not being chunk-aligned though.
                   1029:                         */
                   1030:                        incr = (intptr_t)chunksize
                   1031:                            - (intptr_t)CHUNK_ADDR2OFFSET(brk_cur);
                   1032:                        if (incr < minsize)
                   1033:                                incr += csize;
                   1034:
                   1035:                        brk_prev = sbrk(incr);
                   1036:                        if (brk_prev == brk_cur) {
                   1037:                                /* Success. */
                   1038:                                malloc_mutex_unlock(&brk_mtx);
                   1039:                                base_pages = brk_cur;
                   1040:                                base_next_addr = base_pages;
                   1041:                                base_past_addr = (void *)((uintptr_t)base_pages
                   1042:                                    + incr);
                   1043: #ifdef MALLOC_STATS
                   1044:                                base_mapped += incr;
                   1045: #endif
                   1046:                                return (false);
                   1047:                        }
                   1048:                } while (brk_prev != (void *)-1);
                   1049:                malloc_mutex_unlock(&brk_mtx);
                   1050:        }
                   1051:        if (minsize == 0) {
                   1052:                /*
                   1053:                 * Failure during initialization doesn't matter, so avoid
                   1054:                 * falling through to the mmap-based page mapping code.
                   1055:                 */
                   1056:                return (true);
                   1057:        }
                   1058: #endif
                   1059:        assert(minsize != 0);
                   1060:        csize = PAGE_CEILING(minsize);
                   1061:        base_pages = pages_map(NULL, csize);
                   1062:        if (base_pages == NULL)
                   1063:                return (true);
                   1064:        base_next_addr = base_pages;
                   1065:        base_past_addr = (void *)((uintptr_t)base_pages + csize);
                   1066: #ifdef MALLOC_STATS
                   1067:        base_mapped += csize;
                   1068: #endif
                   1069:        return (false);
                   1070: }
                   1071:
                   1072: static void *
                   1073: base_alloc(size_t size)
                   1074: {
                   1075:        void *ret;
                   1076:        size_t csize;
                   1077:
                   1078:        /* Round size up to nearest multiple of the cacheline size. */
                   1079:        csize = CACHELINE_CEILING(size);
                   1080:
                   1081:        malloc_mutex_lock(&base_mtx);
                   1082:
                   1083:        /* Make sure there's enough space for the allocation. */
                   1084:        if ((uintptr_t)base_next_addr + csize > (uintptr_t)base_past_addr) {
                   1085:                if (base_pages_alloc(csize)) {
                   1086:                        ret = NULL;
                   1087:                        goto RETURN;
                   1088:                }
                   1089:        }
                   1090:
                   1091:        /* Allocate. */
                   1092:        ret = base_next_addr;
                   1093:        base_next_addr = (void *)((uintptr_t)base_next_addr + csize);
                   1094:
                   1095: RETURN:
                   1096:        malloc_mutex_unlock(&base_mtx);
                   1097:        return (ret);
                   1098: }
                   1099:
                   1100: static chunk_node_t *
                   1101: base_chunk_node_alloc(void)
                   1102: {
                   1103:        chunk_node_t *ret;
                   1104:
                   1105:        malloc_mutex_lock(&base_mtx);
                   1106:        if (base_chunk_nodes != NULL) {
                   1107:                ret = base_chunk_nodes;
1.2       ad       1108:                /* LINTED */
1.1       ad       1109:                base_chunk_nodes = *(chunk_node_t **)ret;
                   1110:                malloc_mutex_unlock(&base_mtx);
                   1111:        } else {
                   1112:                malloc_mutex_unlock(&base_mtx);
                   1113:                ret = (chunk_node_t *)base_alloc(sizeof(chunk_node_t));
                   1114:        }
                   1115:
                   1116:        return (ret);
                   1117: }
                   1118:
                   1119: static void
                   1120: base_chunk_node_dealloc(chunk_node_t *node)
                   1121: {
                   1122:
                   1123:        malloc_mutex_lock(&base_mtx);
1.2       ad       1124:        /* LINTED */
1.1       ad       1125:        *(chunk_node_t **)node = base_chunk_nodes;
                   1126:        base_chunk_nodes = node;
                   1127:        malloc_mutex_unlock(&base_mtx);
                   1128: }
                   1129:
                   1130: /******************************************************************************/
                   1131:
                   1132: #ifdef MALLOC_STATS
                   1133: static void
                   1134: stats_print(arena_t *arena)
                   1135: {
                   1136:        unsigned i;
                   1137:        int gap_start;
                   1138:
                   1139:        malloc_printf(
                   1140:            "          allocated/mapped            nmalloc      ndalloc\n");
1.2       ad       1141:
                   1142:        malloc_printf("small: %12zu %-12s %12llu %12llu\n",
1.1       ad       1143:            arena->stats.allocated_small, "", arena->stats.nmalloc_small,
                   1144:            arena->stats.ndalloc_small);
1.2       ad       1145:        malloc_printf("large: %12zu %-12s %12llu %12llu\n",
1.1       ad       1146:            arena->stats.allocated_large, "", arena->stats.nmalloc_large,
                   1147:            arena->stats.ndalloc_large);
1.2       ad       1148:        malloc_printf("total: %12zu/%-12zu %12llu %12llu\n",
1.1       ad       1149:            arena->stats.allocated_small + arena->stats.allocated_large,
                   1150:            arena->stats.mapped,
                   1151:            arena->stats.nmalloc_small + arena->stats.nmalloc_large,
                   1152:            arena->stats.ndalloc_small + arena->stats.ndalloc_large);
                   1153:
                   1154:        malloc_printf("bins:     bin   size regs pgs  requests   newruns"
                   1155:            "    reruns maxruns curruns\n");
                   1156:        for (i = 0, gap_start = -1; i < ntbins + nqbins + nsbins; i++) {
                   1157:                if (arena->bins[i].stats.nrequests == 0) {
                   1158:                        if (gap_start == -1)
                   1159:                                gap_start = i;
                   1160:                } else {
                   1161:                        if (gap_start != -1) {
                   1162:                                if (i > gap_start + 1) {
                   1163:                                        /* Gap of more than one size class. */
                   1164:                                        malloc_printf("[%u..%u]\n",
                   1165:                                            gap_start, i - 1);
                   1166:                                } else {
                   1167:                                        /* Gap of one size class. */
                   1168:                                        malloc_printf("[%u]\n", gap_start);
                   1169:                                }
                   1170:                                gap_start = -1;
                   1171:                        }
                   1172:                        malloc_printf(
                   1173:                            "%13u %1s %4u %4u %3u %9llu %9llu"
                   1174:                            " %9llu %7lu %7lu\n",
                   1175:                            i,
                   1176:                            i < ntbins ? "T" : i < ntbins + nqbins ? "Q" : "S",
                   1177:                            arena->bins[i].reg_size,
                   1178:                            arena->bins[i].nregs,
                   1179:                            arena->bins[i].run_size >> pagesize_2pow,
                   1180:                            arena->bins[i].stats.nrequests,
                   1181:                            arena->bins[i].stats.nruns,
                   1182:                            arena->bins[i].stats.reruns,
                   1183:                            arena->bins[i].stats.highruns,
                   1184:                            arena->bins[i].stats.curruns);
                   1185:                }
                   1186:        }
                   1187:        if (gap_start != -1) {
                   1188:                if (i > gap_start + 1) {
                   1189:                        /* Gap of more than one size class. */
                   1190:                        malloc_printf("[%u..%u]\n", gap_start, i - 1);
                   1191:                } else {
                   1192:                        /* Gap of one size class. */
                   1193:                        malloc_printf("[%u]\n", gap_start);
                   1194:                }
                   1195:        }
                   1196: }
                   1197: #endif
                   1198:
                   1199: /*
                   1200:  * End Utility functions/macros.
                   1201:  */
                   1202: /******************************************************************************/
                   1203: /*
                   1204:  * Begin chunk management functions.
                   1205:  */
                   1206:
1.7       yamt     1207: #ifndef lint
1.1       ad       1208: static inline int
                   1209: chunk_comp(chunk_node_t *a, chunk_node_t *b)
                   1210: {
                   1211:
                   1212:        assert(a != NULL);
                   1213:        assert(b != NULL);
                   1214:
                   1215:        if ((uintptr_t)a->chunk < (uintptr_t)b->chunk)
                   1216:                return (-1);
                   1217:        else if (a->chunk == b->chunk)
                   1218:                return (0);
                   1219:        else
                   1220:                return (1);
                   1221: }
                   1222:
                   1223: /* Generate red-black tree code for chunks. */
                   1224: RB_GENERATE_STATIC(chunk_tree_s, chunk_node_s, link, chunk_comp);
1.2       ad       1225: #endif
1.1       ad       1226:
                   1227: static void *
1.5       yamt     1228: pages_map_align(void *addr, size_t size, int align)
1.1       ad       1229: {
                   1230:        void *ret;
                   1231:
                   1232:        /*
                   1233:         * We don't use MAP_FIXED here, because it can cause the *replacement*
                   1234:         * of existing mappings, and we only want to create new mappings.
                   1235:         */
1.5       yamt     1236:        ret = mmap(addr, size, PROT_READ | PROT_WRITE,
                   1237:            MAP_PRIVATE | MAP_ANON | MAP_ALIGNED(align), -1, 0);
1.1       ad       1238:        assert(ret != NULL);
                   1239:
                   1240:        if (ret == MAP_FAILED)
                   1241:                ret = NULL;
                   1242:        else if (addr != NULL && ret != addr) {
                   1243:                /*
                   1244:                 * We succeeded in mapping memory, but not in the right place.
                   1245:                 */
                   1246:                if (munmap(ret, size) == -1) {
                   1247:                        char buf[STRERROR_BUF];
                   1248:
1.16      christos 1249:                        STRERROR_R(errno, buf, sizeof(buf));
                   1250:                        _malloc_message(getprogname(),
1.1       ad       1251:                            ": (malloc) Error in munmap(): ", buf, "\n");
                   1252:                        if (opt_abort)
                   1253:                                abort();
                   1254:                }
                   1255:                ret = NULL;
                   1256:        }
                   1257:
                   1258:        assert(ret == NULL || (addr == NULL && ret != addr)
                   1259:            || (addr != NULL && ret == addr));
                   1260:        return (ret);
                   1261: }
                   1262:
1.5       yamt     1263: static void *
                   1264: pages_map(void *addr, size_t size)
                   1265: {
                   1266:
                   1267:        return pages_map_align(addr, size, 0);
                   1268: }
                   1269:
1.1       ad       1270: static void
                   1271: pages_unmap(void *addr, size_t size)
                   1272: {
                   1273:
                   1274:        if (munmap(addr, size) == -1) {
                   1275:                char buf[STRERROR_BUF];
                   1276:
1.16      christos 1277:                STRERROR_R(errno, buf, sizeof(buf));
                   1278:                _malloc_message(getprogname(),
1.1       ad       1279:                    ": (malloc) Error in munmap(): ", buf, "\n");
                   1280:                if (opt_abort)
                   1281:                        abort();
                   1282:        }
                   1283: }
                   1284:
                   1285: static void *
                   1286: chunk_alloc(size_t size)
                   1287: {
                   1288:        void *ret, *chunk;
                   1289:        chunk_node_t *tchunk, *delchunk;
                   1290:
                   1291:        assert(size != 0);
                   1292:        assert((size & chunksize_mask) == 0);
                   1293:
                   1294:        malloc_mutex_lock(&chunks_mtx);
                   1295:
                   1296:        if (size == chunksize) {
                   1297:                /*
                   1298:                 * Check for address ranges that were previously chunks and try
                   1299:                 * to use them.
                   1300:                 */
                   1301:
1.2       ad       1302:                /* LINTED */
1.1       ad       1303:                tchunk = RB_MIN(chunk_tree_s, &old_chunks);
                   1304:                while (tchunk != NULL) {
                   1305:                        /* Found an address range.  Try to recycle it. */
                   1306:
                   1307:                        chunk = tchunk->chunk;
                   1308:                        delchunk = tchunk;
1.2       ad       1309:                        /* LINTED */
1.1       ad       1310:                        tchunk = RB_NEXT(chunk_tree_s, &old_chunks, delchunk);
                   1311:
                   1312:                        /* Remove delchunk from the tree. */
1.2       ad       1313:                        /* LINTED */
1.1       ad       1314:                        RB_REMOVE(chunk_tree_s, &old_chunks, delchunk);
                   1315:                        base_chunk_node_dealloc(delchunk);
                   1316:
                   1317: #ifdef USE_BRK
                   1318:                        if ((uintptr_t)chunk >= (uintptr_t)brk_base
                   1319:                            && (uintptr_t)chunk < (uintptr_t)brk_max) {
                   1320:                                /* Re-use a previously freed brk chunk. */
                   1321:                                ret = chunk;
                   1322:                                goto RETURN;
                   1323:                        }
                   1324: #endif
                   1325:                        if ((ret = pages_map(chunk, size)) != NULL) {
                   1326:                                /* Success. */
                   1327:                                goto RETURN;
                   1328:                        }
                   1329:                }
                   1330:        }
                   1331:
                   1332:        /*
                   1333:         * Try to over-allocate, but allow the OS to place the allocation
                   1334:         * anywhere.  Beware of size_t wrap-around.
                   1335:         */
                   1336:        if (size + chunksize > size) {
1.5       yamt     1337:                if ((ret = pages_map_align(NULL, size, chunksize_2pow))
                   1338:                    != NULL) {
1.1       ad       1339:                        goto RETURN;
                   1340:                }
                   1341:        }
                   1342:
                   1343: #ifdef USE_BRK
                   1344:        /*
                   1345:         * Try to create allocations in brk, in order to make full use of
                   1346:         * limited address space.
                   1347:         */
                   1348:        if (brk_prev != (void *)-1) {
                   1349:                void *brk_cur;
                   1350:                intptr_t incr;
                   1351:
                   1352:                /*
                   1353:                 * The loop is necessary to recover from races with other
                   1354:                 * threads that are using brk for something other than malloc.
                   1355:                 */
                   1356:                malloc_mutex_lock(&brk_mtx);
                   1357:                do {
                   1358:                        /* Get the current end of brk. */
                   1359:                        brk_cur = sbrk(0);
                   1360:
                   1361:                        /*
                   1362:                         * Calculate how much padding is necessary to
                   1363:                         * chunk-align the end of brk.
                   1364:                         */
                   1365:                        incr = (intptr_t)size
                   1366:                            - (intptr_t)CHUNK_ADDR2OFFSET(brk_cur);
                   1367:                        if (incr == size) {
                   1368:                                ret = brk_cur;
                   1369:                        } else {
                   1370:                                ret = (void *)((intptr_t)brk_cur + incr);
                   1371:                                incr += size;
                   1372:                        }
                   1373:
                   1374:                        brk_prev = sbrk(incr);
                   1375:                        if (brk_prev == brk_cur) {
                   1376:                                /* Success. */
                   1377:                                malloc_mutex_unlock(&brk_mtx);
                   1378:                                brk_max = (void *)((intptr_t)ret + size);
                   1379:                                goto RETURN;
                   1380:                        }
                   1381:                } while (brk_prev != (void *)-1);
                   1382:                malloc_mutex_unlock(&brk_mtx);
                   1383:        }
                   1384: #endif
                   1385:
                   1386:        /* All strategies for allocation failed. */
                   1387:        ret = NULL;
                   1388: RETURN:
                   1389:        if (ret != NULL) {
                   1390:                chunk_node_t key;
                   1391:                /*
                   1392:                 * Clean out any entries in old_chunks that overlap with the
                   1393:                 * memory we just allocated.
                   1394:                 */
                   1395:                key.chunk = ret;
1.2       ad       1396:                /* LINTED */
1.1       ad       1397:                tchunk = RB_NFIND(chunk_tree_s, &old_chunks, &key);
                   1398:                while (tchunk != NULL
                   1399:                    && (uintptr_t)tchunk->chunk >= (uintptr_t)ret
                   1400:                    && (uintptr_t)tchunk->chunk < (uintptr_t)ret + size) {
                   1401:                        delchunk = tchunk;
1.2       ad       1402:                        /* LINTED */
1.1       ad       1403:                        tchunk = RB_NEXT(chunk_tree_s, &old_chunks, delchunk);
1.2       ad       1404:                        /* LINTED */
1.1       ad       1405:                        RB_REMOVE(chunk_tree_s, &old_chunks, delchunk);
                   1406:                        base_chunk_node_dealloc(delchunk);
                   1407:                }
                   1408:
                   1409:        }
                   1410: #ifdef MALLOC_STATS
                   1411:        if (ret != NULL) {
                   1412:                stats_chunks.nchunks += (size / chunksize);
                   1413:                stats_chunks.curchunks += (size / chunksize);
                   1414:        }
                   1415:        if (stats_chunks.curchunks > stats_chunks.highchunks)
                   1416:                stats_chunks.highchunks = stats_chunks.curchunks;
                   1417: #endif
                   1418:        malloc_mutex_unlock(&chunks_mtx);
                   1419:
                   1420:        assert(CHUNK_ADDR2BASE(ret) == ret);
                   1421:        return (ret);
                   1422: }
                   1423:
                   1424: static void
                   1425: chunk_dealloc(void *chunk, size_t size)
                   1426: {
                   1427:        chunk_node_t *node;
                   1428:
                   1429:        assert(chunk != NULL);
                   1430:        assert(CHUNK_ADDR2BASE(chunk) == chunk);
                   1431:        assert(size != 0);
                   1432:        assert((size & chunksize_mask) == 0);
                   1433:
                   1434:        malloc_mutex_lock(&chunks_mtx);
                   1435:
                   1436: #ifdef USE_BRK
                   1437:        if ((uintptr_t)chunk >= (uintptr_t)brk_base
                   1438:            && (uintptr_t)chunk < (uintptr_t)brk_max) {
                   1439:                void *brk_cur;
                   1440:
                   1441:                malloc_mutex_lock(&brk_mtx);
                   1442:                /* Get the current end of brk. */
                   1443:                brk_cur = sbrk(0);
                   1444:
                   1445:                /*
                   1446:                 * Try to shrink the data segment if this chunk is at the end
                   1447:                 * of the data segment.  The sbrk() call here is subject to a
                   1448:                 * race condition with threads that use brk(2) or sbrk(2)
                   1449:                 * directly, but the alternative would be to leak memory for
                   1450:                 * the sake of poorly designed multi-threaded programs.
                   1451:                 */
                   1452:                if (brk_cur == brk_max
                   1453:                    && (void *)((uintptr_t)chunk + size) == brk_max
                   1454:                    && sbrk(-(intptr_t)size) == brk_max) {
                   1455:                        malloc_mutex_unlock(&brk_mtx);
                   1456:                        if (brk_prev == brk_max) {
                   1457:                                /* Success. */
                   1458:                                brk_prev = (void *)((intptr_t)brk_max
                   1459:                                    - (intptr_t)size);
                   1460:                                brk_max = brk_prev;
                   1461:                        }
                   1462:                } else {
                   1463:                        size_t offset;
                   1464:
                   1465:                        malloc_mutex_unlock(&brk_mtx);
                   1466:                        madvise(chunk, size, MADV_FREE);
                   1467:
                   1468:                        /*
                   1469:                         * Iteratively create records of each chunk-sized
                   1470:                         * memory region that 'chunk' is comprised of, so that
                   1471:                         * the address range can be recycled if memory usage
                   1472:                         * increases later on.
                   1473:                         */
                   1474:                        for (offset = 0; offset < size; offset += chunksize) {
                   1475:                                node = base_chunk_node_alloc();
                   1476:                                if (node == NULL)
                   1477:                                        break;
                   1478:
                   1479:                                node->chunk = (void *)((uintptr_t)chunk
                   1480:                                    + (uintptr_t)offset);
                   1481:                                node->size = chunksize;
1.2       ad       1482:                                /* LINTED */
1.1       ad       1483:                                RB_INSERT(chunk_tree_s, &old_chunks, node);
                   1484:                        }
                   1485:                }
                   1486:        } else {
                   1487: #endif
                   1488:                pages_unmap(chunk, size);
                   1489:
                   1490:                /*
                   1491:                 * Make a record of the chunk's address, so that the address
                   1492:                 * range can be recycled if memory usage increases later on.
                   1493:                 * Don't bother to create entries if (size > chunksize), since
                   1494:                 * doing so could cause scalability issues for truly gargantuan
                   1495:                 * objects (many gigabytes or larger).
                   1496:                 */
                   1497:                if (size == chunksize) {
                   1498:                        node = base_chunk_node_alloc();
                   1499:                        if (node != NULL) {
                   1500:                                node->chunk = (void *)(uintptr_t)chunk;
                   1501:                                node->size = chunksize;
1.2       ad       1502:                                /* LINTED */
1.1       ad       1503:                                RB_INSERT(chunk_tree_s, &old_chunks, node);
                   1504:                        }
                   1505:                }
                   1506: #ifdef USE_BRK
                   1507:        }
                   1508: #endif
                   1509:
                   1510: #ifdef MALLOC_STATS
                   1511:        stats_chunks.curchunks -= (size / chunksize);
                   1512: #endif
                   1513:        malloc_mutex_unlock(&chunks_mtx);
                   1514: }
                   1515:
                   1516: /*
                   1517:  * End chunk management functions.
                   1518:  */
                   1519: /******************************************************************************/
                   1520: /*
                   1521:  * Begin arena.
                   1522:  */
                   1523:
                   1524: /*
1.17      ad       1525:  * Choose an arena based on a per-thread and (optimistically) per-CPU value.
                   1526:  *
                   1527:  * We maintain at least one block of arenas.  Usually there are more.
                   1528:  * The blocks are $ncpu arenas in size.  Whole blocks are 'hashed'
                   1529:  * amongst threads.  To accomplish this, next_arena advances only in
                   1530:  * ncpu steps.
1.1       ad       1531:  */
1.19      ad       1532: static __noinline arena_t *
                   1533: choose_arena_hard(void)
1.1       ad       1534: {
1.17      ad       1535:        unsigned i, curcpu;
                   1536:        arena_t **map;
1.1       ad       1537:
1.17      ad       1538:        /* Initialize the current block of arenas and advance to next. */
1.1       ad       1539:        malloc_mutex_lock(&arenas_mtx);
1.17      ad       1540:        assert(next_arena % ncpus == 0);
                   1541:        assert(narenas % ncpus == 0);
                   1542:        map = &arenas[next_arena];
                   1543:        set_arenas_map(map);
                   1544:        for (i = 0; i < ncpus; i++) {
                   1545:                if (arenas[next_arena] == NULL)
                   1546:                        arenas_extend(next_arena);
                   1547:                next_arena = (next_arena + 1) % narenas;
1.15      ad       1548:        }
1.1       ad       1549:        malloc_mutex_unlock(&arenas_mtx);
                   1550:
1.17      ad       1551:        /*
                   1552:         * If we were unable to allocate an arena above, then default to
                   1553:         * the first arena, which is always present.
                   1554:         */
                   1555:        curcpu = thr_curcpu();
                   1556:        if (map[curcpu] != NULL)
                   1557:                return map[curcpu];
                   1558:        return arenas[0];
1.1       ad       1559: }
                   1560:
1.19      ad       1561: static inline arena_t *
                   1562: choose_arena(void)
                   1563: {
                   1564:        unsigned curcpu;
                   1565:        arena_t **map;
                   1566:
                   1567:        map = get_arenas_map();
                   1568:        curcpu = thr_curcpu();
                   1569:        if (__predict_true(map != NULL && map[curcpu] != NULL))
                   1570:                return map[curcpu];
                   1571:
                   1572:         return choose_arena_hard();
                   1573: }
                   1574:
1.7       yamt     1575: #ifndef lint
1.1       ad       1576: static inline int
                   1577: arena_chunk_comp(arena_chunk_t *a, arena_chunk_t *b)
                   1578: {
                   1579:
                   1580:        assert(a != NULL);
                   1581:        assert(b != NULL);
                   1582:
                   1583:        if ((uintptr_t)a < (uintptr_t)b)
                   1584:                return (-1);
                   1585:        else if (a == b)
                   1586:                return (0);
                   1587:        else
                   1588:                return (1);
                   1589: }
                   1590:
                   1591: /* Generate red-black tree code for arena chunks. */
                   1592: RB_GENERATE_STATIC(arena_chunk_tree_s, arena_chunk_s, link, arena_chunk_comp);
1.2       ad       1593: #endif
1.1       ad       1594:
1.7       yamt     1595: #ifndef lint
1.1       ad       1596: static inline int
                   1597: arena_run_comp(arena_run_t *a, arena_run_t *b)
                   1598: {
                   1599:
                   1600:        assert(a != NULL);
                   1601:        assert(b != NULL);
                   1602:
                   1603:        if ((uintptr_t)a < (uintptr_t)b)
                   1604:                return (-1);
                   1605:        else if (a == b)
                   1606:                return (0);
                   1607:        else
                   1608:                return (1);
                   1609: }
                   1610:
                   1611: /* Generate red-black tree code for arena runs. */
                   1612: RB_GENERATE_STATIC(arena_run_tree_s, arena_run_s, link, arena_run_comp);
1.2       ad       1613: #endif
1.1       ad       1614:
                   1615: static inline void *
                   1616: arena_run_reg_alloc(arena_run_t *run, arena_bin_t *bin)
                   1617: {
                   1618:        void *ret;
                   1619:        unsigned i, mask, bit, regind;
                   1620:
                   1621:        assert(run->magic == ARENA_RUN_MAGIC);
                   1622:        assert(run->regs_minelm < bin->regs_mask_nelms);
                   1623:
                   1624:        /*
                   1625:         * Move the first check outside the loop, so that run->regs_minelm can
                   1626:         * be updated unconditionally, without the possibility of updating it
                   1627:         * multiple times.
                   1628:         */
                   1629:        i = run->regs_minelm;
                   1630:        mask = run->regs_mask[i];
                   1631:        if (mask != 0) {
                   1632:                /* Usable allocation found. */
                   1633:                bit = ffs((int)mask) - 1;
                   1634:
                   1635:                regind = ((i << (SIZEOF_INT_2POW + 3)) + bit);
                   1636:                ret = (void *)(((uintptr_t)run) + bin->reg0_offset
                   1637:                    + (bin->reg_size * regind));
                   1638:
                   1639:                /* Clear bit. */
                   1640:                mask ^= (1 << bit);
                   1641:                run->regs_mask[i] = mask;
                   1642:
                   1643:                return (ret);
                   1644:        }
                   1645:
                   1646:        for (i++; i < bin->regs_mask_nelms; i++) {
                   1647:                mask = run->regs_mask[i];
                   1648:                if (mask != 0) {
                   1649:                        /* Usable allocation found. */
                   1650:                        bit = ffs((int)mask) - 1;
                   1651:
                   1652:                        regind = ((i << (SIZEOF_INT_2POW + 3)) + bit);
                   1653:                        ret = (void *)(((uintptr_t)run) + bin->reg0_offset
                   1654:                            + (bin->reg_size * regind));
                   1655:
                   1656:                        /* Clear bit. */
                   1657:                        mask ^= (1 << bit);
                   1658:                        run->regs_mask[i] = mask;
                   1659:
                   1660:                        /*
                   1661:                         * Make a note that nothing before this element
                   1662:                         * contains a free region.
                   1663:                         */
                   1664:                        run->regs_minelm = i; /* Low payoff: + (mask == 0); */
                   1665:
                   1666:                        return (ret);
                   1667:                }
                   1668:        }
                   1669:        /* Not reached. */
1.7       yamt     1670:        /* LINTED */
1.1       ad       1671:        assert(0);
                   1672:        return (NULL);
                   1673: }
                   1674:
                   1675: static inline void
                   1676: arena_run_reg_dalloc(arena_run_t *run, arena_bin_t *bin, void *ptr, size_t size)
                   1677: {
                   1678:        /*
                   1679:         * To divide by a number D that is not a power of two we multiply
                   1680:         * by (2^21 / D) and then right shift by 21 positions.
                   1681:         *
                   1682:         *   X / D
                   1683:         *
                   1684:         * becomes
                   1685:         *
                   1686:         *   (X * size_invs[(D >> QUANTUM_2POW_MIN) - 3]) >> SIZE_INV_SHIFT
                   1687:         */
                   1688: #define SIZE_INV_SHIFT 21
                   1689: #define SIZE_INV(s) (((1 << SIZE_INV_SHIFT) / (s << QUANTUM_2POW_MIN)) + 1)
                   1690:        static const unsigned size_invs[] = {
                   1691:            SIZE_INV(3),
                   1692:            SIZE_INV(4), SIZE_INV(5), SIZE_INV(6), SIZE_INV(7),
                   1693:            SIZE_INV(8), SIZE_INV(9), SIZE_INV(10), SIZE_INV(11),
                   1694:            SIZE_INV(12),SIZE_INV(13), SIZE_INV(14), SIZE_INV(15),
                   1695:            SIZE_INV(16),SIZE_INV(17), SIZE_INV(18), SIZE_INV(19),
                   1696:            SIZE_INV(20),SIZE_INV(21), SIZE_INV(22), SIZE_INV(23),
                   1697:            SIZE_INV(24),SIZE_INV(25), SIZE_INV(26), SIZE_INV(27),
                   1698:            SIZE_INV(28),SIZE_INV(29), SIZE_INV(30), SIZE_INV(31)
                   1699: #if (QUANTUM_2POW_MIN < 4)
                   1700:            ,
                   1701:            SIZE_INV(32), SIZE_INV(33), SIZE_INV(34), SIZE_INV(35),
                   1702:            SIZE_INV(36), SIZE_INV(37), SIZE_INV(38), SIZE_INV(39),
                   1703:            SIZE_INV(40), SIZE_INV(41), SIZE_INV(42), SIZE_INV(43),
                   1704:            SIZE_INV(44), SIZE_INV(45), SIZE_INV(46), SIZE_INV(47),
                   1705:            SIZE_INV(48), SIZE_INV(49), SIZE_INV(50), SIZE_INV(51),
                   1706:            SIZE_INV(52), SIZE_INV(53), SIZE_INV(54), SIZE_INV(55),
                   1707:            SIZE_INV(56), SIZE_INV(57), SIZE_INV(58), SIZE_INV(59),
                   1708:            SIZE_INV(60), SIZE_INV(61), SIZE_INV(62), SIZE_INV(63)
                   1709: #endif
                   1710:        };
                   1711:        unsigned diff, regind, elm, bit;
                   1712:
1.7       yamt     1713:        /* LINTED */
1.1       ad       1714:        assert(run->magic == ARENA_RUN_MAGIC);
                   1715:        assert(((sizeof(size_invs)) / sizeof(unsigned)) + 3
                   1716:            >= (SMALL_MAX_DEFAULT >> QUANTUM_2POW_MIN));
                   1717:
                   1718:        /*
                   1719:         * Avoid doing division with a variable divisor if possible.  Using
                   1720:         * actual division here can reduce allocator throughput by over 20%!
                   1721:         */
                   1722:        diff = (unsigned)((uintptr_t)ptr - (uintptr_t)run - bin->reg0_offset);
                   1723:        if ((size & (size - 1)) == 0) {
                   1724:                /*
                   1725:                 * log2_table allows fast division of a power of two in the
                   1726:                 * [1..128] range.
                   1727:                 *
                   1728:                 * (x / divisor) becomes (x >> log2_table[divisor - 1]).
                   1729:                 */
                   1730:                static const unsigned char log2_table[] = {
                   1731:                    0, 1, 0, 2, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 4,
                   1732:                    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5,
                   1733:                    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                   1734:                    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6,
                   1735:                    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                   1736:                    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                   1737:                    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                   1738:                    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7
                   1739:                };
                   1740:
                   1741:                if (size <= 128)
                   1742:                        regind = (diff >> log2_table[size - 1]);
                   1743:                else if (size <= 32768)
                   1744:                        regind = diff >> (8 + log2_table[(size >> 8) - 1]);
                   1745:                else {
                   1746:                        /*
                   1747:                         * The page size is too large for us to use the lookup
                   1748:                         * table.  Use real division.
                   1749:                         */
1.9       christos 1750:                        regind = (unsigned)(diff / size);
1.1       ad       1751:                }
                   1752:        } else if (size <= ((sizeof(size_invs) / sizeof(unsigned))
                   1753:            << QUANTUM_2POW_MIN) + 2) {
                   1754:                regind = size_invs[(size >> QUANTUM_2POW_MIN) - 3] * diff;
                   1755:                regind >>= SIZE_INV_SHIFT;
                   1756:        } else {
                   1757:                /*
                   1758:                 * size_invs isn't large enough to handle this size class, so
                   1759:                 * calculate regind using actual division.  This only happens
                   1760:                 * if the user increases small_max via the 'S' runtime
                   1761:                 * configuration option.
                   1762:                 */
1.9       christos 1763:                regind = (unsigned)(diff / size);
1.1       ad       1764:        };
                   1765:        assert(diff == regind * size);
                   1766:        assert(regind < bin->nregs);
                   1767:
                   1768:        elm = regind >> (SIZEOF_INT_2POW + 3);
                   1769:        if (elm < run->regs_minelm)
                   1770:                run->regs_minelm = elm;
                   1771:        bit = regind - (elm << (SIZEOF_INT_2POW + 3));
                   1772:        assert((run->regs_mask[elm] & (1 << bit)) == 0);
                   1773:        run->regs_mask[elm] |= (1 << bit);
                   1774: #undef SIZE_INV
                   1775: #undef SIZE_INV_SHIFT
                   1776: }
                   1777:
                   1778: static void
                   1779: arena_run_split(arena_t *arena, arena_run_t *run, size_t size)
                   1780: {
                   1781:        arena_chunk_t *chunk;
                   1782:        unsigned run_ind, map_offset, total_pages, need_pages, rem_pages;
                   1783:        unsigned i;
                   1784:
                   1785:        chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(run);
                   1786:        run_ind = (unsigned)(((uintptr_t)run - (uintptr_t)chunk)
                   1787:            >> pagesize_2pow);
                   1788:        total_pages = chunk->map[run_ind].npages;
1.9       christos 1789:        need_pages = (unsigned)(size >> pagesize_2pow);
1.1       ad       1790:        assert(need_pages <= total_pages);
                   1791:        rem_pages = total_pages - need_pages;
                   1792:
                   1793:        /* Split enough pages from the front of run to fit allocation size. */
                   1794:        map_offset = run_ind;
                   1795:        for (i = 0; i < need_pages; i++) {
                   1796:                chunk->map[map_offset + i].npages = need_pages;
                   1797:                chunk->map[map_offset + i].pos = i;
                   1798:        }
                   1799:
                   1800:        /* Keep track of trailing unused pages for later use. */
                   1801:        if (rem_pages > 0) {
                   1802:                /* Update map for trailing pages. */
                   1803:                map_offset += need_pages;
                   1804:                chunk->map[map_offset].npages = rem_pages;
                   1805:                chunk->map[map_offset].pos = POS_FREE;
                   1806:                chunk->map[map_offset + rem_pages - 1].npages = rem_pages;
                   1807:                chunk->map[map_offset + rem_pages - 1].pos = POS_FREE;
                   1808:        }
                   1809:
                   1810:        chunk->pages_used += need_pages;
                   1811: }
                   1812:
                   1813: static arena_chunk_t *
                   1814: arena_chunk_alloc(arena_t *arena)
                   1815: {
                   1816:        arena_chunk_t *chunk;
                   1817:
                   1818:        if (arena->spare != NULL) {
                   1819:                chunk = arena->spare;
                   1820:                arena->spare = NULL;
                   1821:
1.2       ad       1822:                /* LINTED */
1.1       ad       1823:                RB_INSERT(arena_chunk_tree_s, &arena->chunks, chunk);
                   1824:        } else {
                   1825:                chunk = (arena_chunk_t *)chunk_alloc(chunksize);
                   1826:                if (chunk == NULL)
                   1827:                        return (NULL);
                   1828: #ifdef MALLOC_STATS
                   1829:                arena->stats.mapped += chunksize;
                   1830: #endif
                   1831:
                   1832:                chunk->arena = arena;
                   1833:
1.2       ad       1834:                /* LINTED */
1.1       ad       1835:                RB_INSERT(arena_chunk_tree_s, &arena->chunks, chunk);
                   1836:
                   1837:                /*
                   1838:                 * Claim that no pages are in use, since the header is merely
                   1839:                 * overhead.
                   1840:                 */
                   1841:                chunk->pages_used = 0;
                   1842:
                   1843:                chunk->max_frun_npages = chunk_npages -
                   1844:                    arena_chunk_header_npages;
                   1845:                chunk->min_frun_ind = arena_chunk_header_npages;
                   1846:
                   1847:                /*
                   1848:                 * Initialize enough of the map to support one maximal free run.
                   1849:                 */
                   1850:                chunk->map[arena_chunk_header_npages].npages = chunk_npages -
                   1851:                    arena_chunk_header_npages;
                   1852:                chunk->map[arena_chunk_header_npages].pos = POS_FREE;
                   1853:                chunk->map[chunk_npages - 1].npages = chunk_npages -
                   1854:                    arena_chunk_header_npages;
                   1855:                chunk->map[chunk_npages - 1].pos = POS_FREE;
                   1856:        }
                   1857:
                   1858:        return (chunk);
                   1859: }
                   1860:
                   1861: static void
                   1862: arena_chunk_dealloc(arena_t *arena, arena_chunk_t *chunk)
                   1863: {
                   1864:
                   1865:        /*
                   1866:         * Remove chunk from the chunk tree, regardless of whether this chunk
                   1867:         * will be cached, so that the arena does not use it.
                   1868:         */
1.2       ad       1869:        /* LINTED */
1.1       ad       1870:        RB_REMOVE(arena_chunk_tree_s, &chunk->arena->chunks, chunk);
                   1871:
                   1872:        if (opt_hint == false) {
                   1873:                if (arena->spare != NULL) {
                   1874:                        chunk_dealloc((void *)arena->spare, chunksize);
                   1875: #ifdef MALLOC_STATS
                   1876:                        arena->stats.mapped -= chunksize;
                   1877: #endif
                   1878:                }
                   1879:                arena->spare = chunk;
                   1880:        } else {
                   1881:                assert(arena->spare == NULL);
                   1882:                chunk_dealloc((void *)chunk, chunksize);
                   1883: #ifdef MALLOC_STATS
                   1884:                arena->stats.mapped -= chunksize;
                   1885: #endif
                   1886:        }
                   1887: }
                   1888:
                   1889: static arena_run_t *
                   1890: arena_run_alloc(arena_t *arena, size_t size)
                   1891: {
                   1892:        arena_chunk_t *chunk;
                   1893:        arena_run_t *run;
                   1894:        unsigned need_npages, limit_pages, compl_need_npages;
                   1895:
                   1896:        assert(size <= (chunksize - (arena_chunk_header_npages <<
                   1897:            pagesize_2pow)));
                   1898:        assert((size & pagesize_mask) == 0);
                   1899:
                   1900:        /*
                   1901:         * Search through arena's chunks in address order for a free run that is
                   1902:         * large enough.  Look for the first fit.
                   1903:         */
1.9       christos 1904:        need_npages = (unsigned)(size >> pagesize_2pow);
1.1       ad       1905:        limit_pages = chunk_npages - arena_chunk_header_npages;
                   1906:        compl_need_npages = limit_pages - need_npages;
1.2       ad       1907:        /* LINTED */
1.1       ad       1908:        RB_FOREACH(chunk, arena_chunk_tree_s, &arena->chunks) {
                   1909:                /*
                   1910:                 * Avoid searching this chunk if there are not enough
                   1911:                 * contiguous free pages for there to possibly be a large
                   1912:                 * enough free run.
                   1913:                 */
                   1914:                if (chunk->pages_used <= compl_need_npages &&
                   1915:                    need_npages <= chunk->max_frun_npages) {
                   1916:                        arena_chunk_map_t *mapelm;
                   1917:                        unsigned i;
                   1918:                        unsigned max_frun_npages = 0;
                   1919:                        unsigned min_frun_ind = chunk_npages;
                   1920:
                   1921:                        assert(chunk->min_frun_ind >=
                   1922:                            arena_chunk_header_npages);
                   1923:                        for (i = chunk->min_frun_ind; i < chunk_npages;) {
                   1924:                                mapelm = &chunk->map[i];
                   1925:                                if (mapelm->pos == POS_FREE) {
                   1926:                                        if (mapelm->npages >= need_npages) {
                   1927:                                                run = (arena_run_t *)
                   1928:                                                    ((uintptr_t)chunk + (i <<
                   1929:                                                    pagesize_2pow));
                   1930:                                                /* Update page map. */
                   1931:                                                arena_run_split(arena, run,
                   1932:                                                    size);
                   1933:                                                return (run);
                   1934:                                        }
                   1935:                                        if (mapelm->npages >
                   1936:                                            max_frun_npages) {
                   1937:                                                max_frun_npages =
                   1938:                                                    mapelm->npages;
                   1939:                                        }
                   1940:                                        if (i < min_frun_ind) {
                   1941:                                                min_frun_ind = i;
                   1942:                                                if (i < chunk->min_frun_ind)
                   1943:                                                        chunk->min_frun_ind = i;
                   1944:                                        }
                   1945:                                }
                   1946:                                i += mapelm->npages;
                   1947:                        }
                   1948:                        /*
                   1949:                         * Search failure.  Reset cached chunk->max_frun_npages.
                   1950:                         * chunk->min_frun_ind was already reset above (if
                   1951:                         * necessary).
                   1952:                         */
                   1953:                        chunk->max_frun_npages = max_frun_npages;
                   1954:                }
                   1955:        }
                   1956:
                   1957:        /*
                   1958:         * No usable runs.  Create a new chunk from which to allocate the run.
                   1959:         */
                   1960:        chunk = arena_chunk_alloc(arena);
                   1961:        if (chunk == NULL)
                   1962:                return (NULL);
                   1963:        run = (arena_run_t *)((uintptr_t)chunk + (arena_chunk_header_npages <<
                   1964:            pagesize_2pow));
                   1965:        /* Update page map. */
                   1966:        arena_run_split(arena, run, size);
                   1967:        return (run);
                   1968: }
                   1969:
                   1970: static void
                   1971: arena_run_dalloc(arena_t *arena, arena_run_t *run, size_t size)
                   1972: {
                   1973:        arena_chunk_t *chunk;
                   1974:        unsigned run_ind, run_pages;
                   1975:
                   1976:        chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(run);
                   1977:
                   1978:        run_ind = (unsigned)(((uintptr_t)run - (uintptr_t)chunk)
                   1979:            >> pagesize_2pow);
                   1980:        assert(run_ind >= arena_chunk_header_npages);
                   1981:        assert(run_ind < (chunksize >> pagesize_2pow));
1.9       christos 1982:        run_pages = (unsigned)(size >> pagesize_2pow);
1.1       ad       1983:        assert(run_pages == chunk->map[run_ind].npages);
                   1984:
                   1985:        /* Subtract pages from count of pages used in chunk. */
                   1986:        chunk->pages_used -= run_pages;
                   1987:
                   1988:        /* Mark run as deallocated. */
                   1989:        assert(chunk->map[run_ind].npages == run_pages);
                   1990:        chunk->map[run_ind].pos = POS_FREE;
                   1991:        assert(chunk->map[run_ind + run_pages - 1].npages == run_pages);
                   1992:        chunk->map[run_ind + run_pages - 1].pos = POS_FREE;
                   1993:
                   1994:        /*
                   1995:         * Tell the kernel that we don't need the data in this run, but only if
                   1996:         * requested via runtime configuration.
                   1997:         */
                   1998:        if (opt_hint)
                   1999:                madvise(run, size, MADV_FREE);
                   2000:
                   2001:        /* Try to coalesce with neighboring runs. */
                   2002:        if (run_ind > arena_chunk_header_npages &&
                   2003:            chunk->map[run_ind - 1].pos == POS_FREE) {
                   2004:                unsigned prev_npages;
                   2005:
                   2006:                /* Coalesce with previous run. */
                   2007:                prev_npages = chunk->map[run_ind - 1].npages;
                   2008:                run_ind -= prev_npages;
                   2009:                assert(chunk->map[run_ind].npages == prev_npages);
                   2010:                assert(chunk->map[run_ind].pos == POS_FREE);
                   2011:                run_pages += prev_npages;
                   2012:
                   2013:                chunk->map[run_ind].npages = run_pages;
                   2014:                assert(chunk->map[run_ind].pos == POS_FREE);
                   2015:                chunk->map[run_ind + run_pages - 1].npages = run_pages;
                   2016:                assert(chunk->map[run_ind + run_pages - 1].pos == POS_FREE);
                   2017:        }
                   2018:
                   2019:        if (run_ind + run_pages < chunk_npages &&
                   2020:            chunk->map[run_ind + run_pages].pos == POS_FREE) {
                   2021:                unsigned next_npages;
                   2022:
                   2023:                /* Coalesce with next run. */
                   2024:                next_npages = chunk->map[run_ind + run_pages].npages;
                   2025:                run_pages += next_npages;
                   2026:                assert(chunk->map[run_ind + run_pages - 1].npages ==
                   2027:                    next_npages);
                   2028:                assert(chunk->map[run_ind + run_pages - 1].pos == POS_FREE);
                   2029:
                   2030:                chunk->map[run_ind].npages = run_pages;
                   2031:                chunk->map[run_ind].pos = POS_FREE;
                   2032:                chunk->map[run_ind + run_pages - 1].npages = run_pages;
                   2033:                assert(chunk->map[run_ind + run_pages - 1].pos == POS_FREE);
                   2034:        }
                   2035:
                   2036:        if (chunk->map[run_ind].npages > chunk->max_frun_npages)
                   2037:                chunk->max_frun_npages = chunk->map[run_ind].npages;
                   2038:        if (run_ind < chunk->min_frun_ind)
                   2039:                chunk->min_frun_ind = run_ind;
                   2040:
                   2041:        /* Deallocate chunk if it is now completely unused. */
                   2042:        if (chunk->pages_used == 0)
                   2043:                arena_chunk_dealloc(arena, chunk);
                   2044: }
                   2045:
                   2046: static arena_run_t *
                   2047: arena_bin_nonfull_run_get(arena_t *arena, arena_bin_t *bin)
                   2048: {
                   2049:        arena_run_t *run;
                   2050:        unsigned i, remainder;
                   2051:
                   2052:        /* Look for a usable run. */
1.2       ad       2053:        /* LINTED */
1.1       ad       2054:        if ((run = RB_MIN(arena_run_tree_s, &bin->runs)) != NULL) {
                   2055:                /* run is guaranteed to have available space. */
1.2       ad       2056:                /* LINTED */
1.1       ad       2057:                RB_REMOVE(arena_run_tree_s, &bin->runs, run);
                   2058: #ifdef MALLOC_STATS
                   2059:                bin->stats.reruns++;
                   2060: #endif
                   2061:                return (run);
                   2062:        }
                   2063:        /* No existing runs have any space available. */
                   2064:
                   2065:        /* Allocate a new run. */
                   2066:        run = arena_run_alloc(arena, bin->run_size);
                   2067:        if (run == NULL)
                   2068:                return (NULL);
                   2069:
                   2070:        /* Initialize run internals. */
                   2071:        run->bin = bin;
                   2072:
                   2073:        for (i = 0; i < bin->regs_mask_nelms; i++)
                   2074:                run->regs_mask[i] = UINT_MAX;
                   2075:        remainder = bin->nregs & ((1 << (SIZEOF_INT_2POW + 3)) - 1);
                   2076:        if (remainder != 0) {
                   2077:                /* The last element has spare bits that need to be unset. */
                   2078:                run->regs_mask[i] = (UINT_MAX >> ((1 << (SIZEOF_INT_2POW + 3))
                   2079:                    - remainder));
                   2080:        }
                   2081:
                   2082:        run->regs_minelm = 0;
                   2083:
                   2084:        run->nfree = bin->nregs;
                   2085: #ifdef MALLOC_DEBUG
                   2086:        run->magic = ARENA_RUN_MAGIC;
                   2087: #endif
                   2088:
                   2089: #ifdef MALLOC_STATS
                   2090:        bin->stats.nruns++;
                   2091:        bin->stats.curruns++;
                   2092:        if (bin->stats.curruns > bin->stats.highruns)
                   2093:                bin->stats.highruns = bin->stats.curruns;
                   2094: #endif
                   2095:        return (run);
                   2096: }
                   2097:
                   2098: /* bin->runcur must have space available before this function is called. */
                   2099: static inline void *
                   2100: arena_bin_malloc_easy(arena_t *arena, arena_bin_t *bin, arena_run_t *run)
                   2101: {
                   2102:        void *ret;
                   2103:
                   2104:        assert(run->magic == ARENA_RUN_MAGIC);
                   2105:        assert(run->nfree > 0);
                   2106:
                   2107:        ret = arena_run_reg_alloc(run, bin);
                   2108:        assert(ret != NULL);
                   2109:        run->nfree--;
                   2110:
                   2111:        return (ret);
                   2112: }
                   2113:
                   2114: /* Re-fill bin->runcur, then call arena_bin_malloc_easy(). */
                   2115: static void *
                   2116: arena_bin_malloc_hard(arena_t *arena, arena_bin_t *bin)
                   2117: {
                   2118:
                   2119:        bin->runcur = arena_bin_nonfull_run_get(arena, bin);
                   2120:        if (bin->runcur == NULL)
                   2121:                return (NULL);
                   2122:        assert(bin->runcur->magic == ARENA_RUN_MAGIC);
                   2123:        assert(bin->runcur->nfree > 0);
                   2124:
                   2125:        return (arena_bin_malloc_easy(arena, bin, bin->runcur));
                   2126: }
                   2127:
                   2128: /*
                   2129:  * Calculate bin->run_size such that it meets the following constraints:
                   2130:  *
                   2131:  *   *) bin->run_size >= min_run_size
                   2132:  *   *) bin->run_size <= arena_maxclass
                   2133:  *   *) bin->run_size <= RUN_MAX_SMALL
                   2134:  *   *) run header overhead <= RUN_MAX_OVRHD (or header overhead relaxed).
                   2135:  *
                   2136:  * bin->nregs, bin->regs_mask_nelms, and bin->reg0_offset are
                   2137:  * also calculated here, since these settings are all interdependent.
                   2138:  */
                   2139: static size_t
                   2140: arena_bin_run_size_calc(arena_bin_t *bin, size_t min_run_size)
                   2141: {
                   2142:        size_t try_run_size, good_run_size;
                   2143:        unsigned good_nregs, good_mask_nelms, good_reg0_offset;
                   2144:        unsigned try_nregs, try_mask_nelms, try_reg0_offset;
                   2145:        float max_ovrhd = RUN_MAX_OVRHD;
                   2146:
                   2147:        assert(min_run_size >= pagesize);
                   2148:        assert(min_run_size <= arena_maxclass);
                   2149:        assert(min_run_size <= RUN_MAX_SMALL);
                   2150:
                   2151:        /*
                   2152:         * Calculate known-valid settings before entering the run_size
                   2153:         * expansion loop, so that the first part of the loop always copies
                   2154:         * valid settings.
                   2155:         *
                   2156:         * The do..while loop iteratively reduces the number of regions until
                   2157:         * the run header and the regions no longer overlap.  A closed formula
                   2158:         * would be quite messy, since there is an interdependency between the
                   2159:         * header's mask length and the number of regions.
                   2160:         */
                   2161:        try_run_size = min_run_size;
1.9       christos 2162:        try_nregs = (unsigned)(((try_run_size - sizeof(arena_run_t)) /
                   2163:            bin->reg_size) + 1); /* Counter-act the first line of the loop. */
1.1       ad       2164:        do {
                   2165:                try_nregs--;
                   2166:                try_mask_nelms = (try_nregs >> (SIZEOF_INT_2POW + 3)) +
                   2167:                    ((try_nregs & ((1 << (SIZEOF_INT_2POW + 3)) - 1)) ? 1 : 0);
1.9       christos 2168:                try_reg0_offset = (unsigned)(try_run_size -
                   2169:                    (try_nregs * bin->reg_size));
1.1       ad       2170:        } while (sizeof(arena_run_t) + (sizeof(unsigned) * (try_mask_nelms - 1))
                   2171:            > try_reg0_offset);
                   2172:
                   2173:        /* run_size expansion loop. */
                   2174:        do {
                   2175:                /*
                   2176:                 * Copy valid settings before trying more aggressive settings.
                   2177:                 */
                   2178:                good_run_size = try_run_size;
                   2179:                good_nregs = try_nregs;
                   2180:                good_mask_nelms = try_mask_nelms;
                   2181:                good_reg0_offset = try_reg0_offset;
                   2182:
                   2183:                /* Try more aggressive settings. */
                   2184:                try_run_size += pagesize;
1.9       christos 2185:                try_nregs = (unsigned)(((try_run_size - sizeof(arena_run_t)) /
                   2186:                    bin->reg_size) + 1); /* Counter-act try_nregs-- in loop. */
1.1       ad       2187:                do {
                   2188:                        try_nregs--;
                   2189:                        try_mask_nelms = (try_nregs >> (SIZEOF_INT_2POW + 3)) +
                   2190:                            ((try_nregs & ((1 << (SIZEOF_INT_2POW + 3)) - 1)) ?
                   2191:                            1 : 0);
1.9       christos 2192:                        try_reg0_offset = (unsigned)(try_run_size - (try_nregs *
                   2193:                            bin->reg_size));
1.1       ad       2194:                } while (sizeof(arena_run_t) + (sizeof(unsigned) *
                   2195:                    (try_mask_nelms - 1)) > try_reg0_offset);
                   2196:        } while (try_run_size <= arena_maxclass && try_run_size <= RUN_MAX_SMALL
                   2197:            && max_ovrhd > RUN_MAX_OVRHD_RELAX / ((float)(bin->reg_size << 3))
                   2198:            && ((float)(try_reg0_offset)) / ((float)(try_run_size)) >
                   2199:            max_ovrhd);
                   2200:
                   2201:        assert(sizeof(arena_run_t) + (sizeof(unsigned) * (good_mask_nelms - 1))
                   2202:            <= good_reg0_offset);
                   2203:        assert((good_mask_nelms << (SIZEOF_INT_2POW + 3)) >= good_nregs);
                   2204:
                   2205:        /* Copy final settings. */
                   2206:        bin->run_size = good_run_size;
                   2207:        bin->nregs = good_nregs;
                   2208:        bin->regs_mask_nelms = good_mask_nelms;
                   2209:        bin->reg0_offset = good_reg0_offset;
                   2210:
                   2211:        return (good_run_size);
                   2212: }
                   2213:
                   2214: static void *
                   2215: arena_malloc(arena_t *arena, size_t size)
                   2216: {
                   2217:        void *ret;
                   2218:
                   2219:        assert(arena != NULL);
                   2220:        assert(arena->magic == ARENA_MAGIC);
                   2221:        assert(size != 0);
                   2222:        assert(QUANTUM_CEILING(size) <= arena_maxclass);
                   2223:
                   2224:        if (size <= bin_maxclass) {
                   2225:                arena_bin_t *bin;
                   2226:                arena_run_t *run;
                   2227:
                   2228:                /* Small allocation. */
                   2229:
                   2230:                if (size < small_min) {
                   2231:                        /* Tiny. */
                   2232:                        size = pow2_ceil(size);
                   2233:                        bin = &arena->bins[ffs((int)(size >> (TINY_MIN_2POW +
                   2234:                            1)))];
                   2235: #if (!defined(NDEBUG) || defined(MALLOC_STATS))
                   2236:                        /*
                   2237:                         * Bin calculation is always correct, but we may need
                   2238:                         * to fix size for the purposes of assertions and/or
                   2239:                         * stats accuracy.
                   2240:                         */
                   2241:                        if (size < (1 << TINY_MIN_2POW))
                   2242:                                size = (1 << TINY_MIN_2POW);
                   2243: #endif
                   2244:                } else if (size <= small_max) {
                   2245:                        /* Quantum-spaced. */
                   2246:                        size = QUANTUM_CEILING(size);
                   2247:                        bin = &arena->bins[ntbins + (size >> opt_quantum_2pow)
                   2248:                            - 1];
                   2249:                } else {
                   2250:                        /* Sub-page. */
                   2251:                        size = pow2_ceil(size);
                   2252:                        bin = &arena->bins[ntbins + nqbins
                   2253:                            + (ffs((int)(size >> opt_small_max_2pow)) - 2)];
                   2254:                }
                   2255:                assert(size == bin->reg_size);
                   2256:
                   2257:                malloc_mutex_lock(&arena->mtx);
                   2258:                if ((run = bin->runcur) != NULL && run->nfree > 0)
                   2259:                        ret = arena_bin_malloc_easy(arena, bin, run);
                   2260:                else
                   2261:                        ret = arena_bin_malloc_hard(arena, bin);
                   2262:
                   2263:                if (ret == NULL) {
                   2264:                        malloc_mutex_unlock(&arena->mtx);
                   2265:                        return (NULL);
                   2266:                }
                   2267:
                   2268: #ifdef MALLOC_STATS
                   2269:                bin->stats.nrequests++;
                   2270:                arena->stats.nmalloc_small++;
                   2271:                arena->stats.allocated_small += size;
                   2272: #endif
                   2273:        } else {
                   2274:                /* Large allocation. */
                   2275:                size = PAGE_CEILING(size);
                   2276:                malloc_mutex_lock(&arena->mtx);
                   2277:                ret = (void *)arena_run_alloc(arena, size);
                   2278:                if (ret == NULL) {
                   2279:                        malloc_mutex_unlock(&arena->mtx);
                   2280:                        return (NULL);
                   2281:                }
                   2282: #ifdef MALLOC_STATS
                   2283:                arena->stats.nmalloc_large++;
                   2284:                arena->stats.allocated_large += size;
                   2285: #endif
                   2286:        }
                   2287:
                   2288:        malloc_mutex_unlock(&arena->mtx);
                   2289:
                   2290:        if (opt_junk)
                   2291:                memset(ret, 0xa5, size);
                   2292:        else if (opt_zero)
                   2293:                memset(ret, 0, size);
                   2294:        return (ret);
                   2295: }
                   2296:
                   2297: static inline void
                   2298: arena_palloc_trim(arena_t *arena, arena_chunk_t *chunk, unsigned pageind,
                   2299:     unsigned npages)
                   2300: {
                   2301:        unsigned i;
                   2302:
                   2303:        assert(npages > 0);
                   2304:
                   2305:        /*
                   2306:         * Modifiy the map such that arena_run_dalloc() sees the run as
                   2307:         * separately allocated.
                   2308:         */
                   2309:        for (i = 0; i < npages; i++) {
                   2310:                chunk->map[pageind + i].npages = npages;
                   2311:                chunk->map[pageind + i].pos = i;
                   2312:        }
                   2313:        arena_run_dalloc(arena, (arena_run_t *)((uintptr_t)chunk + (pageind <<
                   2314:            pagesize_2pow)), npages << pagesize_2pow);
                   2315: }
                   2316:
                   2317: /* Only handles large allocations that require more than page alignment. */
                   2318: static void *
                   2319: arena_palloc(arena_t *arena, size_t alignment, size_t size, size_t alloc_size)
                   2320: {
                   2321:        void *ret;
                   2322:        size_t offset;
                   2323:        arena_chunk_t *chunk;
                   2324:        unsigned pageind, i, npages;
                   2325:
                   2326:        assert((size & pagesize_mask) == 0);
                   2327:        assert((alignment & pagesize_mask) == 0);
                   2328:
1.9       christos 2329:        npages = (unsigned)(size >> pagesize_2pow);
1.1       ad       2330:
                   2331:        malloc_mutex_lock(&arena->mtx);
                   2332:        ret = (void *)arena_run_alloc(arena, alloc_size);
                   2333:        if (ret == NULL) {
                   2334:                malloc_mutex_unlock(&arena->mtx);
                   2335:                return (NULL);
                   2336:        }
                   2337:
                   2338:        chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ret);
                   2339:
                   2340:        offset = (uintptr_t)ret & (alignment - 1);
                   2341:        assert((offset & pagesize_mask) == 0);
                   2342:        assert(offset < alloc_size);
                   2343:        if (offset == 0) {
1.9       christos 2344:                pageind = (unsigned)(((uintptr_t)ret - (uintptr_t)chunk) >>
1.1       ad       2345:                    pagesize_2pow);
                   2346:
                   2347:                /* Update the map for the run to be kept. */
                   2348:                for (i = 0; i < npages; i++) {
                   2349:                        chunk->map[pageind + i].npages = npages;
                   2350:                        assert(chunk->map[pageind + i].pos == i);
                   2351:                }
                   2352:
                   2353:                /* Trim trailing space. */
                   2354:                arena_palloc_trim(arena, chunk, pageind + npages,
1.9       christos 2355:                    (unsigned)((alloc_size - size) >> pagesize_2pow));
1.1       ad       2356:        } else {
                   2357:                size_t leadsize, trailsize;
                   2358:
                   2359:                leadsize = alignment - offset;
                   2360:                ret = (void *)((uintptr_t)ret + leadsize);
1.9       christos 2361:                pageind = (unsigned)(((uintptr_t)ret - (uintptr_t)chunk) >>
1.1       ad       2362:                    pagesize_2pow);
                   2363:
                   2364:                /* Update the map for the run to be kept. */
                   2365:                for (i = 0; i < npages; i++) {
                   2366:                        chunk->map[pageind + i].npages = npages;
                   2367:                        chunk->map[pageind + i].pos = i;
                   2368:                }
                   2369:
                   2370:                /* Trim leading space. */
1.9       christos 2371:                arena_palloc_trim(arena, chunk,
                   2372:                    (unsigned)(pageind - (leadsize >> pagesize_2pow)),
                   2373:                    (unsigned)(leadsize >> pagesize_2pow));
1.1       ad       2374:
                   2375:                trailsize = alloc_size - leadsize - size;
                   2376:                if (trailsize != 0) {
                   2377:                        /* Trim trailing space. */
                   2378:                        assert(trailsize < alloc_size);
                   2379:                        arena_palloc_trim(arena, chunk, pageind + npages,
1.9       christos 2380:                            (unsigned)(trailsize >> pagesize_2pow));
1.1       ad       2381:                }
                   2382:        }
                   2383:
                   2384: #ifdef MALLOC_STATS
                   2385:        arena->stats.nmalloc_large++;
                   2386:        arena->stats.allocated_large += size;
                   2387: #endif
                   2388:        malloc_mutex_unlock(&arena->mtx);
                   2389:
                   2390:        if (opt_junk)
                   2391:                memset(ret, 0xa5, size);
                   2392:        else if (opt_zero)
                   2393:                memset(ret, 0, size);
                   2394:        return (ret);
                   2395: }
                   2396:
                   2397: /* Return the size of the allocation pointed to by ptr. */
                   2398: static size_t
                   2399: arena_salloc(const void *ptr)
                   2400: {
                   2401:        size_t ret;
                   2402:        arena_chunk_t *chunk;
                   2403:        arena_chunk_map_t *mapelm;
                   2404:        unsigned pageind;
                   2405:
                   2406:        assert(ptr != NULL);
                   2407:        assert(CHUNK_ADDR2BASE(ptr) != ptr);
                   2408:
                   2409:        /*
                   2410:         * No arena data structures that we query here can change in a way that
                   2411:         * affects this function, so we don't need to lock.
                   2412:         */
                   2413:        chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
1.9       christos 2414:        pageind = (unsigned)(((uintptr_t)ptr - (uintptr_t)chunk) >>
                   2415:            pagesize_2pow);
1.1       ad       2416:        mapelm = &chunk->map[pageind];
1.10      simonb   2417:        if (mapelm->pos != 0 || ptr != (char *)((uintptr_t)chunk) + (pageind <<
                   2418:            pagesize_2pow)) {
                   2419:                arena_run_t *run;
1.1       ad       2420:
                   2421:                pageind -= mapelm->pos;
                   2422:
1.10      simonb   2423:                run = (arena_run_t *)((uintptr_t)chunk + (pageind <<
                   2424:                    pagesize_2pow));
1.1       ad       2425:                assert(run->magic == ARENA_RUN_MAGIC);
                   2426:                ret = run->bin->reg_size;
                   2427:        } else
                   2428:                ret = mapelm->npages << pagesize_2pow;
                   2429:
                   2430:        return (ret);
                   2431: }
                   2432:
                   2433: static void *
                   2434: arena_ralloc(void *ptr, size_t size, size_t oldsize)
                   2435: {
                   2436:        void *ret;
                   2437:
                   2438:        /* Avoid moving the allocation if the size class would not change. */
                   2439:        if (size < small_min) {
                   2440:                if (oldsize < small_min &&
                   2441:                    ffs((int)(pow2_ceil(size) >> (TINY_MIN_2POW + 1)))
                   2442:                    == ffs((int)(pow2_ceil(oldsize) >> (TINY_MIN_2POW + 1))))
                   2443:                        goto IN_PLACE;
                   2444:        } else if (size <= small_max) {
                   2445:                if (oldsize >= small_min && oldsize <= small_max &&
                   2446:                    (QUANTUM_CEILING(size) >> opt_quantum_2pow)
                   2447:                    == (QUANTUM_CEILING(oldsize) >> opt_quantum_2pow))
                   2448:                        goto IN_PLACE;
                   2449:        } else {
                   2450:                /*
                   2451:                 * We make no attempt to resize runs here, though it would be
                   2452:                 * possible to do so.
                   2453:                 */
                   2454:                if (oldsize > small_max && PAGE_CEILING(size) == oldsize)
                   2455:                        goto IN_PLACE;
                   2456:        }
                   2457:
                   2458:        /*
                   2459:         * If we get here, then size and oldsize are different enough that we
                   2460:         * need to use a different size class.  In that case, fall back to
                   2461:         * allocating new space and copying.
                   2462:         */
                   2463:        ret = arena_malloc(choose_arena(), size);
                   2464:        if (ret == NULL)
                   2465:                return (NULL);
                   2466:
                   2467:        /* Junk/zero-filling were already done by arena_malloc(). */
                   2468:        if (size < oldsize)
                   2469:                memcpy(ret, ptr, size);
                   2470:        else
                   2471:                memcpy(ret, ptr, oldsize);
                   2472:        idalloc(ptr);
                   2473:        return (ret);
                   2474: IN_PLACE:
                   2475:        if (opt_junk && size < oldsize)
                   2476:                memset((void *)((uintptr_t)ptr + size), 0x5a, oldsize - size);
                   2477:        else if (opt_zero && size > oldsize)
                   2478:                memset((void *)((uintptr_t)ptr + oldsize), 0, size - oldsize);
                   2479:        return (ptr);
                   2480: }
                   2481:
                   2482: static void
                   2483: arena_dalloc(arena_t *arena, arena_chunk_t *chunk, void *ptr)
                   2484: {
                   2485:        unsigned pageind;
                   2486:        arena_chunk_map_t *mapelm;
                   2487:        size_t size;
                   2488:
                   2489:        assert(arena != NULL);
                   2490:        assert(arena->magic == ARENA_MAGIC);
                   2491:        assert(chunk->arena == arena);
                   2492:        assert(ptr != NULL);
                   2493:        assert(CHUNK_ADDR2BASE(ptr) != ptr);
                   2494:
1.9       christos 2495:        pageind = (unsigned)(((uintptr_t)ptr - (uintptr_t)chunk) >>
                   2496:            pagesize_2pow);
1.1       ad       2497:        mapelm = &chunk->map[pageind];
1.10      simonb   2498:        if (mapelm->pos != 0 || ptr != (char *)((uintptr_t)chunk) + (pageind <<
                   2499:            pagesize_2pow)) {
                   2500:                arena_run_t *run;
1.1       ad       2501:                arena_bin_t *bin;
                   2502:
                   2503:                /* Small allocation. */
                   2504:
                   2505:                pageind -= mapelm->pos;
                   2506:
1.10      simonb   2507:                run = (arena_run_t *)((uintptr_t)chunk + (pageind <<
                   2508:                    pagesize_2pow));
1.1       ad       2509:                assert(run->magic == ARENA_RUN_MAGIC);
                   2510:                bin = run->bin;
                   2511:                size = bin->reg_size;
                   2512:
                   2513:                if (opt_junk)
                   2514:                        memset(ptr, 0x5a, size);
                   2515:
                   2516:                malloc_mutex_lock(&arena->mtx);
                   2517:                arena_run_reg_dalloc(run, bin, ptr, size);
                   2518:                run->nfree++;
                   2519:
                   2520:                if (run->nfree == bin->nregs) {
                   2521:                        /* Deallocate run. */
                   2522:                        if (run == bin->runcur)
                   2523:                                bin->runcur = NULL;
                   2524:                        else if (bin->nregs != 1) {
                   2525:                                /*
                   2526:                                 * This block's conditional is necessary because
                   2527:                                 * if the run only contains one region, then it
                   2528:                                 * never gets inserted into the non-full runs
                   2529:                                 * tree.
                   2530:                                 */
1.2       ad       2531:                                /* LINTED */
1.1       ad       2532:                                RB_REMOVE(arena_run_tree_s, &bin->runs, run);
                   2533:                        }
                   2534: #ifdef MALLOC_DEBUG
                   2535:                        run->magic = 0;
                   2536: #endif
                   2537:                        arena_run_dalloc(arena, run, bin->run_size);
                   2538: #ifdef MALLOC_STATS
                   2539:                        bin->stats.curruns--;
                   2540: #endif
                   2541:                } else if (run->nfree == 1 && run != bin->runcur) {
                   2542:                        /*
                   2543:                         * Make sure that bin->runcur always refers to the
                   2544:                         * lowest non-full run, if one exists.
                   2545:                         */
                   2546:                        if (bin->runcur == NULL)
                   2547:                                bin->runcur = run;
                   2548:                        else if ((uintptr_t)run < (uintptr_t)bin->runcur) {
                   2549:                                /* Switch runcur. */
                   2550:                                if (bin->runcur->nfree > 0) {
                   2551:                                        /* Insert runcur. */
1.2       ad       2552:                                        /* LINTED */
1.1       ad       2553:                                        RB_INSERT(arena_run_tree_s, &bin->runs,
                   2554:                                            bin->runcur);
                   2555:                                }
                   2556:                                bin->runcur = run;
1.2       ad       2557:                        } else {
                   2558:                                /* LINTED */
1.1       ad       2559:                                RB_INSERT(arena_run_tree_s, &bin->runs, run);
1.2       ad       2560:                        }
1.1       ad       2561:                }
                   2562: #ifdef MALLOC_STATS
                   2563:                arena->stats.allocated_small -= size;
                   2564:                arena->stats.ndalloc_small++;
                   2565: #endif
                   2566:        } else {
                   2567:                /* Large allocation. */
                   2568:
                   2569:                size = mapelm->npages << pagesize_2pow;
                   2570:                assert((((uintptr_t)ptr) & pagesize_mask) == 0);
                   2571:
                   2572:                if (opt_junk)
                   2573:                        memset(ptr, 0x5a, size);
                   2574:
                   2575:                malloc_mutex_lock(&arena->mtx);
                   2576:                arena_run_dalloc(arena, (arena_run_t *)ptr, size);
                   2577: #ifdef MALLOC_STATS
                   2578:                arena->stats.allocated_large -= size;
                   2579:                arena->stats.ndalloc_large++;
                   2580: #endif
                   2581:        }
                   2582:
                   2583:        malloc_mutex_unlock(&arena->mtx);
                   2584: }
                   2585:
                   2586: static bool
                   2587: arena_new(arena_t *arena)
                   2588: {
                   2589:        unsigned i;
                   2590:        arena_bin_t *bin;
1.2       ad       2591:        size_t prev_run_size;
1.1       ad       2592:
                   2593:        malloc_mutex_init(&arena->mtx);
                   2594:
                   2595: #ifdef MALLOC_STATS
                   2596:        memset(&arena->stats, 0, sizeof(arena_stats_t));
                   2597: #endif
                   2598:
                   2599:        /* Initialize chunks. */
                   2600:        RB_INIT(&arena->chunks);
                   2601:        arena->spare = NULL;
                   2602:
                   2603:        /* Initialize bins. */
                   2604:        prev_run_size = pagesize;
                   2605:
                   2606:        /* (2^n)-spaced tiny bins. */
                   2607:        for (i = 0; i < ntbins; i++) {
                   2608:                bin = &arena->bins[i];
                   2609:                bin->runcur = NULL;
                   2610:                RB_INIT(&bin->runs);
                   2611:
                   2612:                bin->reg_size = (1 << (TINY_MIN_2POW + i));
                   2613:                prev_run_size = arena_bin_run_size_calc(bin, prev_run_size);
                   2614:
                   2615: #ifdef MALLOC_STATS
                   2616:                memset(&bin->stats, 0, sizeof(malloc_bin_stats_t));
                   2617: #endif
                   2618:        }
                   2619:
                   2620:        /* Quantum-spaced bins. */
                   2621:        for (; i < ntbins + nqbins; i++) {
                   2622:                bin = &arena->bins[i];
                   2623:                bin->runcur = NULL;
                   2624:                RB_INIT(&bin->runs);
                   2625:
                   2626:                bin->reg_size = quantum * (i - ntbins + 1);
1.2       ad       2627: /*
1.1       ad       2628:                pow2_size = pow2_ceil(quantum * (i - ntbins + 1));
1.2       ad       2629: */
1.1       ad       2630:                prev_run_size = arena_bin_run_size_calc(bin, prev_run_size);
                   2631:
                   2632: #ifdef MALLOC_STATS
                   2633:                memset(&bin->stats, 0, sizeof(malloc_bin_stats_t));
                   2634: #endif
                   2635:        }
                   2636:
                   2637:        /* (2^n)-spaced sub-page bins. */
                   2638:        for (; i < ntbins + nqbins + nsbins; i++) {
                   2639:                bin = &arena->bins[i];
                   2640:                bin->runcur = NULL;
                   2641:                RB_INIT(&bin->runs);
                   2642:
                   2643:                bin->reg_size = (small_max << (i - (ntbins + nqbins) + 1));
                   2644:
                   2645:                prev_run_size = arena_bin_run_size_calc(bin, prev_run_size);
                   2646:
                   2647: #ifdef MALLOC_STATS
                   2648:                memset(&bin->stats, 0, sizeof(malloc_bin_stats_t));
                   2649: #endif
                   2650:        }
                   2651:
                   2652: #ifdef MALLOC_DEBUG
                   2653:        arena->magic = ARENA_MAGIC;
                   2654: #endif
                   2655:
                   2656:        return (false);
                   2657: }
                   2658:
                   2659: /* Create a new arena and insert it into the arenas array at index ind. */
                   2660: static arena_t *
                   2661: arenas_extend(unsigned ind)
                   2662: {
                   2663:        arena_t *ret;
                   2664:
                   2665:        /* Allocate enough space for trailing bins. */
                   2666:        ret = (arena_t *)base_alloc(sizeof(arena_t)
                   2667:            + (sizeof(arena_bin_t) * (ntbins + nqbins + nsbins - 1)));
                   2668:        if (ret != NULL && arena_new(ret) == false) {
                   2669:                arenas[ind] = ret;
                   2670:                return (ret);
                   2671:        }
                   2672:        /* Only reached if there is an OOM error. */
                   2673:
                   2674:        /*
                   2675:         * OOM here is quite inconvenient to propagate, since dealing with it
                   2676:         * would require a check for failure in the fast path.  Instead, punt
                   2677:         * by using arenas[0].  In practice, this is an extremely unlikely
                   2678:         * failure.
                   2679:         */
1.16      christos 2680:        _malloc_message(getprogname(),
1.1       ad       2681:            ": (malloc) Error initializing arena\n", "", "");
                   2682:        if (opt_abort)
                   2683:                abort();
                   2684:
                   2685:        return (arenas[0]);
                   2686: }
                   2687:
                   2688: /*
                   2689:  * End arena.
                   2690:  */
                   2691: /******************************************************************************/
                   2692: /*
                   2693:  * Begin general internal functions.
                   2694:  */
                   2695:
                   2696: static void *
                   2697: huge_malloc(size_t size)
                   2698: {
                   2699:        void *ret;
                   2700:        size_t csize;
                   2701:        chunk_node_t *node;
                   2702:
                   2703:        /* Allocate one or more contiguous chunks for this request. */
                   2704:
                   2705:        csize = CHUNK_CEILING(size);
                   2706:        if (csize == 0) {
                   2707:                /* size is large enough to cause size_t wrap-around. */
                   2708:                return (NULL);
                   2709:        }
                   2710:
                   2711:        /* Allocate a chunk node with which to track the chunk. */
                   2712:        node = base_chunk_node_alloc();
                   2713:        if (node == NULL)
                   2714:                return (NULL);
                   2715:
                   2716:        ret = chunk_alloc(csize);
                   2717:        if (ret == NULL) {
                   2718:                base_chunk_node_dealloc(node);
                   2719:                return (NULL);
                   2720:        }
                   2721:
                   2722:        /* Insert node into huge. */
                   2723:        node->chunk = ret;
                   2724:        node->size = csize;
                   2725:
                   2726:        malloc_mutex_lock(&chunks_mtx);
                   2727:        RB_INSERT(chunk_tree_s, &huge, node);
                   2728: #ifdef MALLOC_STATS
                   2729:        huge_nmalloc++;
                   2730:        huge_allocated += csize;
                   2731: #endif
                   2732:        malloc_mutex_unlock(&chunks_mtx);
                   2733:
                   2734:        if (opt_junk)
                   2735:                memset(ret, 0xa5, csize);
                   2736:        else if (opt_zero)
                   2737:                memset(ret, 0, csize);
                   2738:
                   2739:        return (ret);
                   2740: }
                   2741:
                   2742: /* Only handles large allocations that require more than chunk alignment. */
                   2743: static void *
                   2744: huge_palloc(size_t alignment, size_t size)
                   2745: {
                   2746:        void *ret;
                   2747:        size_t alloc_size, chunk_size, offset;
                   2748:        chunk_node_t *node;
                   2749:
                   2750:        /*
                   2751:         * This allocation requires alignment that is even larger than chunk
                   2752:         * alignment.  This means that huge_malloc() isn't good enough.
                   2753:         *
                   2754:         * Allocate almost twice as many chunks as are demanded by the size or
                   2755:         * alignment, in order to assure the alignment can be achieved, then
                   2756:         * unmap leading and trailing chunks.
                   2757:         */
                   2758:        assert(alignment >= chunksize);
                   2759:
                   2760:        chunk_size = CHUNK_CEILING(size);
                   2761:
                   2762:        if (size >= alignment)
                   2763:                alloc_size = chunk_size + alignment - chunksize;
                   2764:        else
                   2765:                alloc_size = (alignment << 1) - chunksize;
                   2766:
                   2767:        /* Allocate a chunk node with which to track the chunk. */
                   2768:        node = base_chunk_node_alloc();
                   2769:        if (node == NULL)
                   2770:                return (NULL);
                   2771:
                   2772:        ret = chunk_alloc(alloc_size);
                   2773:        if (ret == NULL) {
                   2774:                base_chunk_node_dealloc(node);
                   2775:                return (NULL);
                   2776:        }
                   2777:
                   2778:        offset = (uintptr_t)ret & (alignment - 1);
                   2779:        assert((offset & chunksize_mask) == 0);
                   2780:        assert(offset < alloc_size);
                   2781:        if (offset == 0) {
                   2782:                /* Trim trailing space. */
                   2783:                chunk_dealloc((void *)((uintptr_t)ret + chunk_size), alloc_size
                   2784:                    - chunk_size);
                   2785:        } else {
                   2786:                size_t trailsize;
                   2787:
                   2788:                /* Trim leading space. */
                   2789:                chunk_dealloc(ret, alignment - offset);
                   2790:
                   2791:                ret = (void *)((uintptr_t)ret + (alignment - offset));
                   2792:
                   2793:                trailsize = alloc_size - (alignment - offset) - chunk_size;
                   2794:                if (trailsize != 0) {
                   2795:                    /* Trim trailing space. */
                   2796:                    assert(trailsize < alloc_size);
                   2797:                    chunk_dealloc((void *)((uintptr_t)ret + chunk_size),
                   2798:                        trailsize);
                   2799:                }
                   2800:        }
                   2801:
                   2802:        /* Insert node into huge. */
                   2803:        node->chunk = ret;
                   2804:        node->size = chunk_size;
                   2805:
                   2806:        malloc_mutex_lock(&chunks_mtx);
                   2807:        RB_INSERT(chunk_tree_s, &huge, node);
                   2808: #ifdef MALLOC_STATS
                   2809:        huge_nmalloc++;
                   2810:        huge_allocated += chunk_size;
                   2811: #endif
                   2812:        malloc_mutex_unlock(&chunks_mtx);
                   2813:
                   2814:        if (opt_junk)
                   2815:                memset(ret, 0xa5, chunk_size);
                   2816:        else if (opt_zero)
                   2817:                memset(ret, 0, chunk_size);
                   2818:
                   2819:        return (ret);
                   2820: }
                   2821:
                   2822: static void *
                   2823: huge_ralloc(void *ptr, size_t size, size_t oldsize)
                   2824: {
                   2825:        void *ret;
                   2826:
                   2827:        /* Avoid moving the allocation if the size class would not change. */
                   2828:        if (oldsize > arena_maxclass &&
                   2829:            CHUNK_CEILING(size) == CHUNK_CEILING(oldsize)) {
                   2830:                if (opt_junk && size < oldsize) {
                   2831:                        memset((void *)((uintptr_t)ptr + size), 0x5a, oldsize
                   2832:                            - size);
                   2833:                } else if (opt_zero && size > oldsize) {
                   2834:                        memset((void *)((uintptr_t)ptr + oldsize), 0, size
                   2835:                            - oldsize);
                   2836:                }
                   2837:                return (ptr);
                   2838:        }
                   2839:
1.8       yamt     2840:        if (CHUNK_ADDR2BASE(ptr) == ptr
                   2841: #ifdef USE_BRK
                   2842:            && ((uintptr_t)ptr < (uintptr_t)brk_base
                   2843:            || (uintptr_t)ptr >= (uintptr_t)brk_max)
                   2844: #endif
                   2845:            ) {
                   2846:                chunk_node_t *node, key;
                   2847:                void *newptr;
                   2848:                size_t oldcsize;
                   2849:                size_t newcsize;
                   2850:
                   2851:                newcsize = CHUNK_CEILING(size);
                   2852:                oldcsize = CHUNK_CEILING(oldsize);
                   2853:                assert(oldcsize != newcsize);
                   2854:                if (newcsize == 0) {
                   2855:                        /* size_t wrap-around */
                   2856:                        return (NULL);
                   2857:                }
1.19.12.1! matt     2858:
        !          2859:                /*
        !          2860:                 * Remove the old region from the tree now.  If mremap()
        !          2861:                 * returns the region to the system, other thread may
        !          2862:                 * map it for same huge allocation and insert it to the
        !          2863:                 * tree before we acquire the mutex lock again.
        !          2864:                 */
        !          2865:                malloc_mutex_lock(&chunks_mtx);
        !          2866:                key.chunk = __DECONST(void *, ptr);
        !          2867:                /* LINTED */
        !          2868:                node = RB_FIND(chunk_tree_s, &huge, &key);
        !          2869:                assert(node != NULL);
        !          2870:                assert(node->chunk == ptr);
        !          2871:                assert(node->size == oldcsize);
        !          2872:                RB_REMOVE(chunk_tree_s, &huge, node);
        !          2873:                malloc_mutex_unlock(&chunks_mtx);
        !          2874:
1.8       yamt     2875:                newptr = mremap(ptr, oldcsize, NULL, newcsize,
                   2876:                    MAP_ALIGNED(chunksize_2pow));
1.19.12.1! matt     2877:                if (newptr == MAP_FAILED) {
        !          2878:                        /* We still own the old region. */
        !          2879:                        malloc_mutex_lock(&chunks_mtx);
        !          2880:                        RB_INSERT(chunk_tree_s, &huge, node);
        !          2881:                        malloc_mutex_unlock(&chunks_mtx);
        !          2882:                } else {
1.8       yamt     2883:                        assert(CHUNK_ADDR2BASE(newptr) == newptr);
                   2884:
1.19.12.1! matt     2885:                        /* Insert new or resized old region. */
1.8       yamt     2886:                        malloc_mutex_lock(&chunks_mtx);
                   2887:                        node->size = newcsize;
1.19.12.1! matt     2888:                        node->chunk = newptr;
        !          2889:                        RB_INSERT(chunk_tree_s, &huge, node);
1.8       yamt     2890: #ifdef MALLOC_STATS
                   2891:                        huge_nralloc++;
                   2892:                        huge_allocated += newcsize - oldcsize;
                   2893:                        if (newcsize > oldcsize) {
                   2894:                                stats_chunks.curchunks +=
                   2895:                                    (newcsize - oldcsize) / chunksize;
                   2896:                                if (stats_chunks.curchunks >
                   2897:                                    stats_chunks.highchunks)
                   2898:                                        stats_chunks.highchunks =
                   2899:                                            stats_chunks.curchunks;
                   2900:                        } else {
                   2901:                                stats_chunks.curchunks -=
                   2902:                                    (oldcsize - newcsize) / chunksize;
                   2903:                        }
                   2904: #endif
                   2905:                        malloc_mutex_unlock(&chunks_mtx);
                   2906:
                   2907:                        if (opt_junk && size < oldsize) {
                   2908:                                memset((void *)((uintptr_t)newptr + size), 0x5a,
                   2909:                                    newcsize - size);
                   2910:                        } else if (opt_zero && size > oldsize) {
                   2911:                                memset((void *)((uintptr_t)newptr + oldsize), 0,
                   2912:                                    size - oldsize);
                   2913:                        }
                   2914:                        return (newptr);
                   2915:                }
                   2916:        }
                   2917:
1.1       ad       2918:        /*
                   2919:         * If we get here, then size and oldsize are different enough that we
                   2920:         * need to use a different size class.  In that case, fall back to
                   2921:         * allocating new space and copying.
                   2922:         */
                   2923:        ret = huge_malloc(size);
                   2924:        if (ret == NULL)
                   2925:                return (NULL);
                   2926:
                   2927:        if (CHUNK_ADDR2BASE(ptr) == ptr) {
                   2928:                /* The old allocation is a chunk. */
                   2929:                if (size < oldsize)
                   2930:                        memcpy(ret, ptr, size);
                   2931:                else
                   2932:                        memcpy(ret, ptr, oldsize);
                   2933:        } else {
                   2934:                /* The old allocation is a region. */
                   2935:                assert(oldsize < size);
                   2936:                memcpy(ret, ptr, oldsize);
                   2937:        }
                   2938:        idalloc(ptr);
                   2939:        return (ret);
                   2940: }
                   2941:
                   2942: static void
                   2943: huge_dalloc(void *ptr)
                   2944: {
                   2945:        chunk_node_t key;
                   2946:        chunk_node_t *node;
                   2947:
                   2948:        malloc_mutex_lock(&chunks_mtx);
                   2949:
                   2950:        /* Extract from tree of huge allocations. */
                   2951:        key.chunk = ptr;
1.2       ad       2952:        /* LINTED */
1.1       ad       2953:        node = RB_FIND(chunk_tree_s, &huge, &key);
                   2954:        assert(node != NULL);
                   2955:        assert(node->chunk == ptr);
1.2       ad       2956:        /* LINTED */
1.1       ad       2957:        RB_REMOVE(chunk_tree_s, &huge, node);
                   2958:
                   2959: #ifdef MALLOC_STATS
                   2960:        huge_ndalloc++;
                   2961:        huge_allocated -= node->size;
                   2962: #endif
                   2963:
                   2964:        malloc_mutex_unlock(&chunks_mtx);
                   2965:
                   2966:        /* Unmap chunk. */
                   2967: #ifdef USE_BRK
                   2968:        if (opt_junk)
                   2969:                memset(node->chunk, 0x5a, node->size);
                   2970: #endif
                   2971:        chunk_dealloc(node->chunk, node->size);
                   2972:
                   2973:        base_chunk_node_dealloc(node);
                   2974: }
                   2975:
                   2976: static void *
                   2977: imalloc(size_t size)
                   2978: {
                   2979:        void *ret;
                   2980:
                   2981:        assert(size != 0);
                   2982:
                   2983:        if (size <= arena_maxclass)
                   2984:                ret = arena_malloc(choose_arena(), size);
                   2985:        else
                   2986:                ret = huge_malloc(size);
                   2987:
                   2988:        return (ret);
                   2989: }
                   2990:
                   2991: static void *
                   2992: ipalloc(size_t alignment, size_t size)
                   2993: {
                   2994:        void *ret;
                   2995:        size_t ceil_size;
                   2996:
                   2997:        /*
                   2998:         * Round size up to the nearest multiple of alignment.
                   2999:         *
                   3000:         * This done, we can take advantage of the fact that for each small
                   3001:         * size class, every object is aligned at the smallest power of two
                   3002:         * that is non-zero in the base two representation of the size.  For
                   3003:         * example:
                   3004:         *
                   3005:         *   Size |   Base 2 | Minimum alignment
                   3006:         *   -----+----------+------------------
                   3007:         *     96 |  1100000 |  32
                   3008:         *    144 | 10100000 |  32
                   3009:         *    192 | 11000000 |  64
                   3010:         *
                   3011:         * Depending on runtime settings, it is possible that arena_malloc()
                   3012:         * will further round up to a power of two, but that never causes
                   3013:         * correctness issues.
                   3014:         */
                   3015:        ceil_size = (size + (alignment - 1)) & (-alignment);
                   3016:        /*
                   3017:         * (ceil_size < size) protects against the combination of maximal
                   3018:         * alignment and size greater than maximal alignment.
                   3019:         */
                   3020:        if (ceil_size < size) {
                   3021:                /* size_t overflow. */
                   3022:                return (NULL);
                   3023:        }
                   3024:
                   3025:        if (ceil_size <= pagesize || (alignment <= pagesize
                   3026:            && ceil_size <= arena_maxclass))
                   3027:                ret = arena_malloc(choose_arena(), ceil_size);
                   3028:        else {
                   3029:                size_t run_size;
                   3030:
                   3031:                /*
                   3032:                 * We can't achieve sub-page alignment, so round up alignment
                   3033:                 * permanently; it makes later calculations simpler.
                   3034:                 */
                   3035:                alignment = PAGE_CEILING(alignment);
                   3036:                ceil_size = PAGE_CEILING(size);
                   3037:                /*
                   3038:                 * (ceil_size < size) protects against very large sizes within
                   3039:                 * pagesize of SIZE_T_MAX.
                   3040:                 *
                   3041:                 * (ceil_size + alignment < ceil_size) protects against the
                   3042:                 * combination of maximal alignment and ceil_size large enough
                   3043:                 * to cause overflow.  This is similar to the first overflow
                   3044:                 * check above, but it needs to be repeated due to the new
                   3045:                 * ceil_size value, which may now be *equal* to maximal
                   3046:                 * alignment, whereas before we only detected overflow if the
                   3047:                 * original size was *greater* than maximal alignment.
                   3048:                 */
                   3049:                if (ceil_size < size || ceil_size + alignment < ceil_size) {
                   3050:                        /* size_t overflow. */
                   3051:                        return (NULL);
                   3052:                }
                   3053:
                   3054:                /*
                   3055:                 * Calculate the size of the over-size run that arena_palloc()
                   3056:                 * would need to allocate in order to guarantee the alignment.
                   3057:                 */
                   3058:                if (ceil_size >= alignment)
                   3059:                        run_size = ceil_size + alignment - pagesize;
                   3060:                else {
                   3061:                        /*
                   3062:                         * It is possible that (alignment << 1) will cause
                   3063:                         * overflow, but it doesn't matter because we also
                   3064:                         * subtract pagesize, which in the case of overflow
                   3065:                         * leaves us with a very large run_size.  That causes
                   3066:                         * the first conditional below to fail, which means
                   3067:                         * that the bogus run_size value never gets used for
                   3068:                         * anything important.
                   3069:                         */
                   3070:                        run_size = (alignment << 1) - pagesize;
                   3071:                }
                   3072:
                   3073:                if (run_size <= arena_maxclass) {
                   3074:                        ret = arena_palloc(choose_arena(), alignment, ceil_size,
                   3075:                            run_size);
                   3076:                } else if (alignment <= chunksize)
                   3077:                        ret = huge_malloc(ceil_size);
                   3078:                else
                   3079:                        ret = huge_palloc(alignment, ceil_size);
                   3080:        }
                   3081:
                   3082:        assert(((uintptr_t)ret & (alignment - 1)) == 0);
                   3083:        return (ret);
                   3084: }
                   3085:
                   3086: static void *
                   3087: icalloc(size_t size)
                   3088: {
                   3089:        void *ret;
                   3090:
                   3091:        if (size <= arena_maxclass) {
                   3092:                ret = arena_malloc(choose_arena(), size);
                   3093:                if (ret == NULL)
                   3094:                        return (NULL);
                   3095:                memset(ret, 0, size);
                   3096:        } else {
                   3097:                /*
                   3098:                 * The virtual memory system provides zero-filled pages, so
                   3099:                 * there is no need to do so manually, unless opt_junk is
                   3100:                 * enabled, in which case huge_malloc() fills huge allocations
                   3101:                 * with junk.
                   3102:                 */
                   3103:                ret = huge_malloc(size);
                   3104:                if (ret == NULL)
                   3105:                        return (NULL);
                   3106:
                   3107:                if (opt_junk)
                   3108:                        memset(ret, 0, size);
                   3109: #ifdef USE_BRK
                   3110:                else if ((uintptr_t)ret >= (uintptr_t)brk_base
                   3111:                    && (uintptr_t)ret < (uintptr_t)brk_max) {
                   3112:                        /*
                   3113:                         * This may be a re-used brk chunk.  Therefore, zero
                   3114:                         * the memory.
                   3115:                         */
                   3116:                        memset(ret, 0, size);
                   3117:                }
                   3118: #endif
                   3119:        }
                   3120:
                   3121:        return (ret);
                   3122: }
                   3123:
                   3124: static size_t
                   3125: isalloc(const void *ptr)
                   3126: {
                   3127:        size_t ret;
                   3128:        arena_chunk_t *chunk;
                   3129:
                   3130:        assert(ptr != NULL);
                   3131:
                   3132:        chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
                   3133:        if (chunk != ptr) {
                   3134:                /* Region. */
                   3135:                assert(chunk->arena->magic == ARENA_MAGIC);
                   3136:
                   3137:                ret = arena_salloc(ptr);
                   3138:        } else {
                   3139:                chunk_node_t *node, key;
                   3140:
                   3141:                /* Chunk (huge allocation). */
                   3142:
                   3143:                malloc_mutex_lock(&chunks_mtx);
                   3144:
                   3145:                /* Extract from tree of huge allocations. */
                   3146:                key.chunk = __DECONST(void *, ptr);
1.2       ad       3147:                /* LINTED */
1.1       ad       3148:                node = RB_FIND(chunk_tree_s, &huge, &key);
                   3149:                assert(node != NULL);
                   3150:
                   3151:                ret = node->size;
                   3152:
                   3153:                malloc_mutex_unlock(&chunks_mtx);
                   3154:        }
                   3155:
                   3156:        return (ret);
                   3157: }
                   3158:
                   3159: static void *
                   3160: iralloc(void *ptr, size_t size)
                   3161: {
                   3162:        void *ret;
                   3163:        size_t oldsize;
                   3164:
                   3165:        assert(ptr != NULL);
                   3166:        assert(size != 0);
                   3167:
                   3168:        oldsize = isalloc(ptr);
                   3169:
                   3170:        if (size <= arena_maxclass)
                   3171:                ret = arena_ralloc(ptr, size, oldsize);
                   3172:        else
                   3173:                ret = huge_ralloc(ptr, size, oldsize);
                   3174:
                   3175:        return (ret);
                   3176: }
                   3177:
                   3178: static void
                   3179: idalloc(void *ptr)
                   3180: {
                   3181:        arena_chunk_t *chunk;
                   3182:
                   3183:        assert(ptr != NULL);
                   3184:
                   3185:        chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
                   3186:        if (chunk != ptr) {
                   3187:                /* Region. */
                   3188:                arena_dalloc(chunk->arena, chunk, ptr);
                   3189:        } else
                   3190:                huge_dalloc(ptr);
                   3191: }
                   3192:
                   3193: static void
                   3194: malloc_print_stats(void)
                   3195: {
                   3196:
                   3197:        if (opt_print_stats) {
                   3198:                char s[UMAX2S_BUFSIZE];
                   3199:                _malloc_message("___ Begin malloc statistics ___\n", "", "",
                   3200:                    "");
                   3201:                _malloc_message("Assertions ",
                   3202: #ifdef NDEBUG
                   3203:                    "disabled",
                   3204: #else
                   3205:                    "enabled",
                   3206: #endif
                   3207:                    "\n", "");
                   3208:                _malloc_message("Boolean MALLOC_OPTIONS: ",
                   3209:                    opt_abort ? "A" : "a",
                   3210:                    opt_junk ? "J" : "j",
                   3211:                    opt_hint ? "H" : "h");
                   3212:                _malloc_message(opt_utrace ? "PU" : "Pu",
                   3213:                    opt_sysv ? "V" : "v",
                   3214:                    opt_xmalloc ? "X" : "x",
                   3215:                    opt_zero ? "Z\n" : "z\n");
                   3216:
                   3217:                _malloc_message("CPUs: ", umax2s(ncpus, s), "\n", "");
                   3218:                _malloc_message("Max arenas: ", umax2s(narenas, s), "\n", "");
                   3219:                _malloc_message("Pointer size: ", umax2s(sizeof(void *), s),
                   3220:                    "\n", "");
                   3221:                _malloc_message("Quantum size: ", umax2s(quantum, s), "\n", "");
                   3222:                _malloc_message("Max small size: ", umax2s(small_max, s), "\n",
                   3223:                    "");
                   3224:
                   3225:                _malloc_message("Chunk size: ", umax2s(chunksize, s), "", "");
                   3226:                _malloc_message(" (2^", umax2s(opt_chunk_2pow, s), ")\n", "");
                   3227:
                   3228: #ifdef MALLOC_STATS
                   3229:                {
                   3230:                        size_t allocated, mapped;
                   3231:                        unsigned i;
                   3232:                        arena_t *arena;
                   3233:
                   3234:                        /* Calculate and print allocated/mapped stats. */
                   3235:
                   3236:                        /* arenas. */
                   3237:                        for (i = 0, allocated = 0; i < narenas; i++) {
                   3238:                                if (arenas[i] != NULL) {
                   3239:                                        malloc_mutex_lock(&arenas[i]->mtx);
                   3240:                                        allocated +=
                   3241:                                            arenas[i]->stats.allocated_small;
                   3242:                                        allocated +=
                   3243:                                            arenas[i]->stats.allocated_large;
                   3244:                                        malloc_mutex_unlock(&arenas[i]->mtx);
                   3245:                                }
                   3246:                        }
                   3247:
                   3248:                        /* huge/base. */
                   3249:                        malloc_mutex_lock(&chunks_mtx);
                   3250:                        allocated += huge_allocated;
                   3251:                        mapped = stats_chunks.curchunks * chunksize;
                   3252:                        malloc_mutex_unlock(&chunks_mtx);
                   3253:
                   3254:                        malloc_mutex_lock(&base_mtx);
                   3255:                        mapped += base_mapped;
                   3256:                        malloc_mutex_unlock(&base_mtx);
                   3257:
                   3258:                        malloc_printf("Allocated: %zu, mapped: %zu\n",
                   3259:                            allocated, mapped);
                   3260:
                   3261:                        /* Print chunk stats. */
                   3262:                        {
                   3263:                                chunk_stats_t chunks_stats;
                   3264:
                   3265:                                malloc_mutex_lock(&chunks_mtx);
                   3266:                                chunks_stats = stats_chunks;
                   3267:                                malloc_mutex_unlock(&chunks_mtx);
                   3268:
                   3269:                                malloc_printf("chunks: nchunks   "
                   3270:                                    "highchunks    curchunks\n");
                   3271:                                malloc_printf("  %13llu%13lu%13lu\n",
                   3272:                                    chunks_stats.nchunks,
                   3273:                                    chunks_stats.highchunks,
                   3274:                                    chunks_stats.curchunks);
                   3275:                        }
                   3276:
                   3277:                        /* Print chunk stats. */
                   3278:                        malloc_printf(
1.8       yamt     3279:                            "huge: nmalloc      ndalloc      "
                   3280:                            "nralloc    allocated\n");
                   3281:                        malloc_printf(" %12llu %12llu %12llu %12zu\n",
                   3282:                            huge_nmalloc, huge_ndalloc, huge_nralloc,
                   3283:                            huge_allocated);
1.1       ad       3284:
                   3285:                        /* Print stats for each arena. */
                   3286:                        for (i = 0; i < narenas; i++) {
                   3287:                                arena = arenas[i];
                   3288:                                if (arena != NULL) {
                   3289:                                        malloc_printf(
1.2       ad       3290:                                            "\narenas[%u] @ %p\n", i, arena);
1.1       ad       3291:                                        malloc_mutex_lock(&arena->mtx);
                   3292:                                        stats_print(arena);
                   3293:                                        malloc_mutex_unlock(&arena->mtx);
                   3294:                                }
                   3295:                        }
                   3296:                }
                   3297: #endif /* #ifdef MALLOC_STATS */
                   3298:                _malloc_message("--- End malloc statistics ---\n", "", "", "");
                   3299:        }
                   3300: }
                   3301:
                   3302: /*
                   3303:  * FreeBSD's pthreads implementation calls malloc(3), so the malloc
                   3304:  * implementation has to take pains to avoid infinite recursion during
                   3305:  * initialization.
                   3306:  */
                   3307: static inline bool
                   3308: malloc_init(void)
                   3309: {
                   3310:
                   3311:        if (malloc_initialized == false)
                   3312:                return (malloc_init_hard());
                   3313:
                   3314:        return (false);
                   3315: }
                   3316:
                   3317: static bool
                   3318: malloc_init_hard(void)
                   3319: {
                   3320:        unsigned i, j;
1.9       christos 3321:        ssize_t linklen;
1.1       ad       3322:        char buf[PATH_MAX + 1];
1.2       ad       3323:        const char *opts = "";
1.1       ad       3324:
                   3325:        malloc_mutex_lock(&init_lock);
                   3326:        if (malloc_initialized) {
                   3327:                /*
                   3328:                 * Another thread initialized the allocator before this one
                   3329:                 * acquired init_lock.
                   3330:                 */
                   3331:                malloc_mutex_unlock(&init_lock);
                   3332:                return (false);
                   3333:        }
                   3334:
                   3335:        /* Get number of CPUs. */
                   3336:        {
                   3337:                int mib[2];
                   3338:                size_t len;
                   3339:
                   3340:                mib[0] = CTL_HW;
                   3341:                mib[1] = HW_NCPU;
                   3342:                len = sizeof(ncpus);
                   3343:                if (sysctl(mib, 2, &ncpus, &len, (void *) 0, 0) == -1) {
                   3344:                        /* Error. */
                   3345:                        ncpus = 1;
                   3346:                }
                   3347:        }
                   3348:
                   3349:        /* Get page size. */
                   3350:        {
                   3351:                long result;
                   3352:
                   3353:                result = sysconf(_SC_PAGESIZE);
                   3354:                assert(result != -1);
                   3355:                pagesize = (unsigned) result;
                   3356:
                   3357:                /*
                   3358:                 * We assume that pagesize is a power of 2 when calculating
                   3359:                 * pagesize_mask and pagesize_2pow.
                   3360:                 */
                   3361:                assert(((result - 1) & result) == 0);
                   3362:                pagesize_mask = result - 1;
                   3363:                pagesize_2pow = ffs((int)result) - 1;
                   3364:        }
                   3365:
                   3366:        for (i = 0; i < 3; i++) {
                   3367:                /* Get runtime configuration. */
                   3368:                switch (i) {
                   3369:                case 0:
                   3370:                        if ((linklen = readlink("/etc/malloc.conf", buf,
                   3371:                                                sizeof(buf) - 1)) != -1) {
                   3372:                                /*
                   3373:                                 * Use the contents of the "/etc/malloc.conf"
                   3374:                                 * symbolic link's name.
                   3375:                                 */
                   3376:                                buf[linklen] = '\0';
                   3377:                                opts = buf;
                   3378:                        } else {
                   3379:                                /* No configuration specified. */
                   3380:                                buf[0] = '\0';
                   3381:                                opts = buf;
                   3382:                        }
                   3383:                        break;
                   3384:                case 1:
1.18      ad       3385:                        if ((opts = getenv("MALLOC_OPTIONS")) != NULL &&
                   3386:                            issetugid() == 0) {
1.1       ad       3387:                                /*
                   3388:                                 * Do nothing; opts is already initialized to
                   3389:                                 * the value of the MALLOC_OPTIONS environment
                   3390:                                 * variable.
                   3391:                                 */
                   3392:                        } else {
                   3393:                                /* No configuration specified. */
                   3394:                                buf[0] = '\0';
                   3395:                                opts = buf;
                   3396:                        }
                   3397:                        break;
                   3398:                case 2:
                   3399:                        if (_malloc_options != NULL) {
                   3400:                            /*
                   3401:                             * Use options that were compiled into the program.
                   3402:                             */
                   3403:                            opts = _malloc_options;
                   3404:                        } else {
                   3405:                                /* No configuration specified. */
                   3406:                                buf[0] = '\0';
                   3407:                                opts = buf;
                   3408:                        }
                   3409:                        break;
                   3410:                default:
                   3411:                        /* NOTREACHED */
1.7       yamt     3412:                        /* LINTED */
1.1       ad       3413:                        assert(false);
                   3414:                }
                   3415:
                   3416:                for (j = 0; opts[j] != '\0'; j++) {
                   3417:                        switch (opts[j]) {
                   3418:                        case 'a':
                   3419:                                opt_abort = false;
                   3420:                                break;
                   3421:                        case 'A':
                   3422:                                opt_abort = true;
                   3423:                                break;
                   3424:                        case 'h':
                   3425:                                opt_hint = false;
                   3426:                                break;
                   3427:                        case 'H':
                   3428:                                opt_hint = true;
                   3429:                                break;
                   3430:                        case 'j':
                   3431:                                opt_junk = false;
                   3432:                                break;
                   3433:                        case 'J':
                   3434:                                opt_junk = true;
                   3435:                                break;
                   3436:                        case 'k':
                   3437:                                /*
                   3438:                                 * Chunks always require at least one header
                   3439:                                 * page, so chunks can never be smaller than
                   3440:                                 * two pages.
                   3441:                                 */
                   3442:                                if (opt_chunk_2pow > pagesize_2pow + 1)
                   3443:                                        opt_chunk_2pow--;
                   3444:                                break;
                   3445:                        case 'K':
                   3446:                                /*
                   3447:                                 * There must be fewer pages in a chunk than
                   3448:                                 * can be recorded by the pos field of
                   3449:                                 * arena_chunk_map_t, in order to make POS_FREE
                   3450:                                 * special.
                   3451:                                 */
                   3452:                                if (opt_chunk_2pow - pagesize_2pow
                   3453:                                    < (sizeof(uint32_t) << 3) - 1)
                   3454:                                        opt_chunk_2pow++;
                   3455:                                break;
                   3456:                        case 'n':
                   3457:                                opt_narenas_lshift--;
                   3458:                                break;
                   3459:                        case 'N':
                   3460:                                opt_narenas_lshift++;
                   3461:                                break;
                   3462:                        case 'p':
                   3463:                                opt_print_stats = false;
                   3464:                                break;
                   3465:                        case 'P':
                   3466:                                opt_print_stats = true;
                   3467:                                break;
                   3468:                        case 'q':
                   3469:                                if (opt_quantum_2pow > QUANTUM_2POW_MIN)
                   3470:                                        opt_quantum_2pow--;
                   3471:                                break;
                   3472:                        case 'Q':
                   3473:                                if (opt_quantum_2pow < pagesize_2pow - 1)
                   3474:                                        opt_quantum_2pow++;
                   3475:                                break;
                   3476:                        case 's':
                   3477:                                if (opt_small_max_2pow > QUANTUM_2POW_MIN)
                   3478:                                        opt_small_max_2pow--;
                   3479:                                break;
                   3480:                        case 'S':
                   3481:                                if (opt_small_max_2pow < pagesize_2pow - 1)
                   3482:                                        opt_small_max_2pow++;
                   3483:                                break;
                   3484:                        case 'u':
                   3485:                                opt_utrace = false;
                   3486:                                break;
                   3487:                        case 'U':
                   3488:                                opt_utrace = true;
                   3489:                                break;
                   3490:                        case 'v':
                   3491:                                opt_sysv = false;
                   3492:                                break;
                   3493:                        case 'V':
                   3494:                                opt_sysv = true;
                   3495:                                break;
                   3496:                        case 'x':
                   3497:                                opt_xmalloc = false;
                   3498:                                break;
                   3499:                        case 'X':
                   3500:                                opt_xmalloc = true;
                   3501:                                break;
                   3502:                        case 'z':
                   3503:                                opt_zero = false;
                   3504:                                break;
                   3505:                        case 'Z':
                   3506:                                opt_zero = true;
                   3507:                                break;
                   3508:                        default: {
                   3509:                                char cbuf[2];
                   3510:
                   3511:                                cbuf[0] = opts[j];
                   3512:                                cbuf[1] = '\0';
1.16      christos 3513:                                _malloc_message(getprogname(),
1.1       ad       3514:                                    ": (malloc) Unsupported character in "
                   3515:                                    "malloc options: '", cbuf, "'\n");
                   3516:                        }
                   3517:                        }
                   3518:                }
                   3519:        }
                   3520:
                   3521:        /* Take care to call atexit() only once. */
                   3522:        if (opt_print_stats) {
                   3523:                /* Print statistics at exit. */
                   3524:                atexit(malloc_print_stats);
                   3525:        }
                   3526:
                   3527:        /* Set variables according to the value of opt_small_max_2pow. */
                   3528:        if (opt_small_max_2pow < opt_quantum_2pow)
                   3529:                opt_small_max_2pow = opt_quantum_2pow;
                   3530:        small_max = (1 << opt_small_max_2pow);
                   3531:
                   3532:        /* Set bin-related variables. */
                   3533:        bin_maxclass = (pagesize >> 1);
                   3534:        assert(opt_quantum_2pow >= TINY_MIN_2POW);
1.9       christos 3535:        ntbins = (unsigned)(opt_quantum_2pow - TINY_MIN_2POW);
1.1       ad       3536:        assert(ntbins <= opt_quantum_2pow);
1.9       christos 3537:        nqbins = (unsigned)(small_max >> opt_quantum_2pow);
                   3538:        nsbins = (unsigned)(pagesize_2pow - opt_small_max_2pow - 1);
1.1       ad       3539:
                   3540:        /* Set variables according to the value of opt_quantum_2pow. */
                   3541:        quantum = (1 << opt_quantum_2pow);
                   3542:        quantum_mask = quantum - 1;
                   3543:        if (ntbins > 0)
                   3544:                small_min = (quantum >> 1) + 1;
                   3545:        else
                   3546:                small_min = 1;
                   3547:        assert(small_min <= quantum);
                   3548:
                   3549:        /* Set variables according to the value of opt_chunk_2pow. */
                   3550:        chunksize = (1LU << opt_chunk_2pow);
                   3551:        chunksize_mask = chunksize - 1;
1.9       christos 3552:        chunksize_2pow = (unsigned)opt_chunk_2pow;
                   3553:        chunk_npages = (unsigned)(chunksize >> pagesize_2pow);
1.1       ad       3554:        {
                   3555:                unsigned header_size;
                   3556:
1.9       christos 3557:                header_size = (unsigned)(sizeof(arena_chunk_t) +
                   3558:                    (sizeof(arena_chunk_map_t) * (chunk_npages - 1)));
1.1       ad       3559:                arena_chunk_header_npages = (header_size >> pagesize_2pow);
                   3560:                if ((header_size & pagesize_mask) != 0)
                   3561:                        arena_chunk_header_npages++;
                   3562:        }
                   3563:        arena_maxclass = chunksize - (arena_chunk_header_npages <<
                   3564:            pagesize_2pow);
                   3565:
                   3566:        UTRACE(0, 0, 0);
                   3567:
                   3568: #ifdef MALLOC_STATS
                   3569:        memset(&stats_chunks, 0, sizeof(chunk_stats_t));
                   3570: #endif
                   3571:
                   3572:        /* Various sanity checks that regard configuration. */
                   3573:        assert(quantum >= sizeof(void *));
                   3574:        assert(quantum <= pagesize);
                   3575:        assert(chunksize >= pagesize);
                   3576:        assert(quantum * 4 <= chunksize);
                   3577:
                   3578:        /* Initialize chunks data. */
                   3579:        malloc_mutex_init(&chunks_mtx);
                   3580:        RB_INIT(&huge);
                   3581: #ifdef USE_BRK
                   3582:        malloc_mutex_init(&brk_mtx);
                   3583:        brk_base = sbrk(0);
                   3584:        brk_prev = brk_base;
                   3585:        brk_max = brk_base;
                   3586: #endif
                   3587: #ifdef MALLOC_STATS
                   3588:        huge_nmalloc = 0;
                   3589:        huge_ndalloc = 0;
1.8       yamt     3590:        huge_nralloc = 0;
1.1       ad       3591:        huge_allocated = 0;
                   3592: #endif
                   3593:        RB_INIT(&old_chunks);
                   3594:
                   3595:        /* Initialize base allocation data structures. */
                   3596: #ifdef MALLOC_STATS
                   3597:        base_mapped = 0;
                   3598: #endif
                   3599: #ifdef USE_BRK
                   3600:        /*
                   3601:         * Allocate a base chunk here, since it doesn't actually have to be
                   3602:         * chunk-aligned.  Doing this before allocating any other chunks allows
                   3603:         * the use of space that would otherwise be wasted.
                   3604:         */
                   3605:        base_pages_alloc(0);
                   3606: #endif
                   3607:        base_chunk_nodes = NULL;
                   3608:        malloc_mutex_init(&base_mtx);
                   3609:
                   3610:        if (ncpus > 1) {
                   3611:                /*
                   3612:                 * For SMP systems, create four times as many arenas as there
                   3613:                 * are CPUs by default.
                   3614:                 */
                   3615:                opt_narenas_lshift += 2;
                   3616:        }
                   3617:
1.2       ad       3618: #ifdef NO_TLS
                   3619:        /* Initialize arena key. */
                   3620:        (void)thr_keycreate(&arenas_map_key, NULL);
                   3621: #endif
                   3622:
1.1       ad       3623:        /* Determine how many arenas to use. */
                   3624:        narenas = ncpus;
                   3625:        if (opt_narenas_lshift > 0) {
                   3626:                if ((narenas << opt_narenas_lshift) > narenas)
                   3627:                        narenas <<= opt_narenas_lshift;
                   3628:                /*
                   3629:                 * Make sure not to exceed the limits of what base_malloc()
                   3630:                 * can handle.
                   3631:                 */
                   3632:                if (narenas * sizeof(arena_t *) > chunksize)
1.9       christos 3633:                        narenas = (unsigned)(chunksize / sizeof(arena_t *));
1.1       ad       3634:        } else if (opt_narenas_lshift < 0) {
                   3635:                if ((narenas << opt_narenas_lshift) < narenas)
                   3636:                        narenas <<= opt_narenas_lshift;
1.15      ad       3637:                /* Make sure there is at least one arena. */
                   3638:                if (narenas == 0)
                   3639:                        narenas = 1;
1.1       ad       3640:        }
                   3641:
                   3642:        next_arena = 0;
                   3643:
                   3644:        /* Allocate and initialize arenas. */
                   3645:        arenas = (arena_t **)base_alloc(sizeof(arena_t *) * narenas);
                   3646:        if (arenas == NULL) {
                   3647:                malloc_mutex_unlock(&init_lock);
                   3648:                return (true);
                   3649:        }
                   3650:        /*
                   3651:         * Zero the array.  In practice, this should always be pre-zeroed,
                   3652:         * since it was just mmap()ed, but let's be sure.
                   3653:         */
                   3654:        memset(arenas, 0, sizeof(arena_t *) * narenas);
                   3655:
                   3656:        /*
                   3657:         * Initialize one arena here.  The rest are lazily created in
                   3658:         * arena_choose_hard().
                   3659:         */
                   3660:        arenas_extend(0);
                   3661:        if (arenas[0] == NULL) {
                   3662:                malloc_mutex_unlock(&init_lock);
                   3663:                return (true);
                   3664:        }
                   3665:
                   3666:        malloc_mutex_init(&arenas_mtx);
                   3667:
                   3668:        malloc_initialized = true;
                   3669:        malloc_mutex_unlock(&init_lock);
                   3670:        return (false);
                   3671: }
                   3672:
                   3673: /*
                   3674:  * End general internal functions.
                   3675:  */
                   3676: /******************************************************************************/
                   3677: /*
                   3678:  * Begin malloc(3)-compatible functions.
                   3679:  */
                   3680:
                   3681: void *
                   3682: malloc(size_t size)
                   3683: {
                   3684:        void *ret;
                   3685:
                   3686:        if (malloc_init()) {
                   3687:                ret = NULL;
                   3688:                goto RETURN;
                   3689:        }
                   3690:
                   3691:        if (size == 0) {
                   3692:                if (opt_sysv == false)
                   3693:                        size = 1;
                   3694:                else {
                   3695:                        ret = NULL;
                   3696:                        goto RETURN;
                   3697:                }
                   3698:        }
                   3699:
                   3700:        ret = imalloc(size);
                   3701:
                   3702: RETURN:
                   3703:        if (ret == NULL) {
                   3704:                if (opt_xmalloc) {
1.16      christos 3705:                        _malloc_message(getprogname(),
1.1       ad       3706:                            ": (malloc) Error in malloc(): out of memory\n", "",
                   3707:                            "");
                   3708:                        abort();
                   3709:                }
                   3710:                errno = ENOMEM;
                   3711:        }
                   3712:
                   3713:        UTRACE(0, size, ret);
                   3714:        return (ret);
                   3715: }
                   3716:
                   3717: int
                   3718: posix_memalign(void **memptr, size_t alignment, size_t size)
                   3719: {
                   3720:        int ret;
                   3721:        void *result;
                   3722:
                   3723:        if (malloc_init())
                   3724:                result = NULL;
                   3725:        else {
                   3726:                /* Make sure that alignment is a large enough power of 2. */
                   3727:                if (((alignment - 1) & alignment) != 0
                   3728:                    || alignment < sizeof(void *)) {
                   3729:                        if (opt_xmalloc) {
1.16      christos 3730:                                _malloc_message(getprogname(),
1.1       ad       3731:                                    ": (malloc) Error in posix_memalign(): "
                   3732:                                    "invalid alignment\n", "", "");
                   3733:                                abort();
                   3734:                        }
                   3735:                        result = NULL;
                   3736:                        ret = EINVAL;
                   3737:                        goto RETURN;
                   3738:                }
                   3739:
                   3740:                result = ipalloc(alignment, size);
                   3741:        }
                   3742:
                   3743:        if (result == NULL) {
                   3744:                if (opt_xmalloc) {
1.16      christos 3745:                        _malloc_message(getprogname(),
1.1       ad       3746:                        ": (malloc) Error in posix_memalign(): out of memory\n",
                   3747:                        "", "");
                   3748:                        abort();
                   3749:                }
                   3750:                ret = ENOMEM;
                   3751:                goto RETURN;
                   3752:        }
                   3753:
                   3754:        *memptr = result;
                   3755:        ret = 0;
                   3756:
                   3757: RETURN:
                   3758:        UTRACE(0, size, result);
                   3759:        return (ret);
                   3760: }
                   3761:
                   3762: void *
                   3763: calloc(size_t num, size_t size)
                   3764: {
                   3765:        void *ret;
                   3766:        size_t num_size;
                   3767:
                   3768:        if (malloc_init()) {
                   3769:                num_size = 0;
                   3770:                ret = NULL;
                   3771:                goto RETURN;
                   3772:        }
                   3773:
                   3774:        num_size = num * size;
                   3775:        if (num_size == 0) {
                   3776:                if ((opt_sysv == false) && ((num == 0) || (size == 0)))
                   3777:                        num_size = 1;
                   3778:                else {
                   3779:                        ret = NULL;
                   3780:                        goto RETURN;
                   3781:                }
                   3782:        /*
                   3783:         * Try to avoid division here.  We know that it isn't possible to
                   3784:         * overflow during multiplication if neither operand uses any of the
                   3785:         * most significant half of the bits in a size_t.
                   3786:         */
1.2       ad       3787:        } else if ((unsigned long long)((num | size) &
                   3788:           ((unsigned long long)SIZE_T_MAX << (sizeof(size_t) << 2))) &&
                   3789:           (num_size / size != num)) {
1.1       ad       3790:                /* size_t overflow. */
                   3791:                ret = NULL;
                   3792:                goto RETURN;
                   3793:        }
                   3794:
                   3795:        ret = icalloc(num_size);
                   3796:
                   3797: RETURN:
                   3798:        if (ret == NULL) {
                   3799:                if (opt_xmalloc) {
1.16      christos 3800:                        _malloc_message(getprogname(),
1.1       ad       3801:                            ": (malloc) Error in calloc(): out of memory\n", "",
                   3802:                            "");
                   3803:                        abort();
                   3804:                }
                   3805:                errno = ENOMEM;
                   3806:        }
                   3807:
                   3808:        UTRACE(0, num_size, ret);
                   3809:        return (ret);
                   3810: }
                   3811:
                   3812: void *
                   3813: realloc(void *ptr, size_t size)
                   3814: {
                   3815:        void *ret;
                   3816:
                   3817:        if (size == 0) {
                   3818:                if (opt_sysv == false)
                   3819:                        size = 1;
                   3820:                else {
                   3821:                        if (ptr != NULL)
                   3822:                                idalloc(ptr);
                   3823:                        ret = NULL;
                   3824:                        goto RETURN;
                   3825:                }
                   3826:        }
                   3827:
                   3828:        if (ptr != NULL) {
                   3829:                assert(malloc_initialized);
                   3830:
                   3831:                ret = iralloc(ptr, size);
                   3832:
                   3833:                if (ret == NULL) {
                   3834:                        if (opt_xmalloc) {
1.16      christos 3835:                                _malloc_message(getprogname(),
1.1       ad       3836:                                    ": (malloc) Error in realloc(): out of "
                   3837:                                    "memory\n", "", "");
                   3838:                                abort();
                   3839:                        }
                   3840:                        errno = ENOMEM;
                   3841:                }
                   3842:        } else {
                   3843:                if (malloc_init())
                   3844:                        ret = NULL;
                   3845:                else
                   3846:                        ret = imalloc(size);
                   3847:
                   3848:                if (ret == NULL) {
                   3849:                        if (opt_xmalloc) {
1.16      christos 3850:                                _malloc_message(getprogname(),
1.1       ad       3851:                                    ": (malloc) Error in realloc(): out of "
                   3852:                                    "memory\n", "", "");
                   3853:                                abort();
                   3854:                        }
                   3855:                        errno = ENOMEM;
                   3856:                }
                   3857:        }
                   3858:
                   3859: RETURN:
                   3860:        UTRACE(ptr, size, ret);
                   3861:        return (ret);
                   3862: }
                   3863:
                   3864: void
                   3865: free(void *ptr)
                   3866: {
                   3867:
                   3868:        UTRACE(ptr, 0, 0);
                   3869:        if (ptr != NULL) {
                   3870:                assert(malloc_initialized);
                   3871:
                   3872:                idalloc(ptr);
                   3873:        }
                   3874: }
                   3875:
                   3876: /*
                   3877:  * End malloc(3)-compatible functions.
                   3878:  */
                   3879: /******************************************************************************/
                   3880: /*
                   3881:  * Begin non-standard functions.
                   3882:  */
1.2       ad       3883: #ifndef __NetBSD__
1.1       ad       3884: size_t
                   3885: malloc_usable_size(const void *ptr)
                   3886: {
                   3887:
                   3888:        assert(ptr != NULL);
                   3889:
                   3890:        return (isalloc(ptr));
                   3891: }
1.2       ad       3892: #endif
1.1       ad       3893:
                   3894: /*
                   3895:  * End non-standard functions.
                   3896:  */
                   3897: /******************************************************************************/
                   3898: /*
                   3899:  * Begin library-private functions, used by threading libraries for protection
                   3900:  * of malloc during fork().  These functions are only called if the program is
                   3901:  * running in threaded mode, so there is no need to check whether the program
                   3902:  * is threaded here.
                   3903:  */
                   3904:
                   3905: void
                   3906: _malloc_prefork(void)
                   3907: {
                   3908:        unsigned i;
                   3909:
                   3910:        /* Acquire all mutexes in a safe order. */
                   3911:
                   3912:        malloc_mutex_lock(&arenas_mtx);
                   3913:        for (i = 0; i < narenas; i++) {
                   3914:                if (arenas[i] != NULL)
                   3915:                        malloc_mutex_lock(&arenas[i]->mtx);
                   3916:        }
                   3917:        malloc_mutex_unlock(&arenas_mtx);
                   3918:
                   3919:        malloc_mutex_lock(&base_mtx);
                   3920:
                   3921:        malloc_mutex_lock(&chunks_mtx);
                   3922: }
                   3923:
                   3924: void
                   3925: _malloc_postfork(void)
                   3926: {
                   3927:        unsigned i;
                   3928:
                   3929:        /* Release all mutexes, now that fork() has completed. */
                   3930:
                   3931:        malloc_mutex_unlock(&chunks_mtx);
                   3932:
                   3933:        malloc_mutex_unlock(&base_mtx);
                   3934:
                   3935:        malloc_mutex_lock(&arenas_mtx);
                   3936:        for (i = 0; i < narenas; i++) {
                   3937:                if (arenas[i] != NULL)
                   3938:                        malloc_mutex_unlock(&arenas[i]->mtx);
                   3939:        }
                   3940:        malloc_mutex_unlock(&arenas_mtx);
                   3941: }
                   3942:
                   3943: /*
                   3944:  * End library-private functions.
                   3945:  */
                   3946: /******************************************************************************/

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