[redis.git] / deps / jemalloc / include / jemalloc / internal / arena.h

/******************************************************************************/
#ifdef JEMALLOC_H_TYPES

/*
 * RUN_MAX_OVRHD indicates maximum desired run header overhead.  Runs are sized
 * as small as possible such that this setting is still honored, without
 * violating other constraints.  The goal is to make runs as small as possible
 * without exceeding a per run external fragmentation threshold.
 *
 * We use binary fixed point math for overhead computations, where the binary
 * point is implicitly RUN_BFP bits to the left.
 *
 * Note that it is possible to set RUN_MAX_OVRHD low enough that it cannot be
 * honored for some/all object sizes, since when heap profiling is enabled
 * there is one pointer of header overhead per object (plus a constant).  This
 * constraint is relaxed (ignored) for runs that are so small that the
 * per-region overhead is greater than:
 *
 *   (RUN_MAX_OVRHD / (reg_interval << (3+RUN_BFP))
 */
#define RUN_BFP                 12
/*                                    \/   Implicit binary fixed point. */
#define RUN_MAX_OVRHD           0x0000003dU
#define RUN_MAX_OVRHD_RELAX     0x00001800U

/* Maximum number of regions in one run. */
#define LG_RUN_MAXREGS          11
#define RUN_MAXREGS             (1U << LG_RUN_MAXREGS)

/*
 * Minimum redzone size.  Redzones may be larger than this if necessary to
 * preserve region alignment.
 */
#define REDZONE_MINSIZE         16

/*
 * The minimum ratio of active:dirty pages per arena is computed as:
 *
 *   (nactive >> opt_lg_dirty_mult) >= ndirty
 *
 * So, supposing that opt_lg_dirty_mult is 5, there can be no less than 32
 * times as many active pages as dirty pages.
 */
#define LG_DIRTY_MULT_DEFAULT   5

typedef struct arena_chunk_map_s arena_chunk_map_t;
typedef struct arena_chunk_s arena_chunk_t;
typedef struct arena_run_s arena_run_t;
typedef struct arena_bin_info_s arena_bin_info_t;
typedef struct arena_bin_s arena_bin_t;
typedef struct arena_s arena_t;

#endif /* JEMALLOC_H_TYPES */
/******************************************************************************/
#ifdef JEMALLOC_H_STRUCTS

/* Each element of the chunk map corresponds to one page within the chunk. */
struct arena_chunk_map_s {
#ifndef JEMALLOC_PROF
        /*
         * Overlay prof_ctx in order to allow it to be referenced by dead code.
         * Such antics aren't warranted for per arena data structures, but
         * chunk map overhead accounts for a percentage of memory, rather than
         * being just a fixed cost.
         */
        union {
#endif
        union {
                /*
                 * Linkage for run trees.  There are two disjoint uses:
                 *
                 * 1) arena_t's runs_avail_{clean,dirty} trees.
                 * 2) arena_run_t conceptually uses this linkage for in-use
                 *    non-full runs, rather than directly embedding linkage.
                 */
                rb_node(arena_chunk_map_t)      rb_link;
                /*
                 * List of runs currently in purgatory.  arena_chunk_purge()
                 * temporarily allocates runs that contain dirty pages while
                 * purging, so that other threads cannot use the runs while the
                 * purging thread is operating without the arena lock held.
                 */
                ql_elm(arena_chunk_map_t)       ql_link;
        }                               u;

        /* Profile counters, used for large object runs. */
        prof_ctx_t                      *prof_ctx;
#ifndef JEMALLOC_PROF
        }; /* union { ... }; */
#endif

        /*
         * Run address (or size) and various flags are stored together.  The bit
         * layout looks like (assuming 32-bit system):
         *
         *   ???????? ???????? ????nnnn nnnndula
         *
         * ? : Unallocated: Run address for first/last pages, unset for internal
         *                  pages.
         *     Small: Run page offset.
         *     Large: Run size for first page, unset for trailing pages.
         * n : binind for small size class, BININD_INVALID for large size class.
         * d : dirty?
         * u : unzeroed?
         * l : large?
         * a : allocated?
         *
         * Following are example bit patterns for the three types of runs.
         *
         * p : run page offset
         * s : run size
         * n : binind for size class; large objects set these to BININD_INVALID
         *     except for promoted allocations (see prof_promote)
         * x : don't care
         * - : 0
         * + : 1
         * [DULA] : bit set
         * [dula] : bit unset
         *
         *   Unallocated (clean):
         *     ssssssss ssssssss ssss++++ ++++du-a
         *     xxxxxxxx xxxxxxxx xxxxxxxx xxxx-Uxx
         *     ssssssss ssssssss ssss++++ ++++dU-a
         *
         *   Unallocated (dirty):
         *     ssssssss ssssssss ssss++++ ++++D--a
         *     xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx
         *     ssssssss ssssssss ssss++++ ++++D--a
         *
         *   Small:
         *     pppppppp pppppppp ppppnnnn nnnnd--A
         *     pppppppp pppppppp ppppnnnn nnnn---A
         *     pppppppp pppppppp ppppnnnn nnnnd--A
         *
         *   Large:
         *     ssssssss ssssssss ssss++++ ++++D-LA
         *     xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx
         *     -------- -------- ----++++ ++++D-LA
         *
         *   Large (sampled, size <= PAGE):
         *     ssssssss ssssssss ssssnnnn nnnnD-LA
         *
         *   Large (not sampled, size == PAGE):
         *     ssssssss ssssssss ssss++++ ++++D-LA
         */
        size_t                          bits;
#define CHUNK_MAP_BININD_SHIFT  4
#define BININD_INVALID          ((size_t)0xffU)
/*     CHUNK_MAP_BININD_MASK == (BININD_INVALID << CHUNK_MAP_BININD_SHIFT) */
#define CHUNK_MAP_BININD_MASK   ((size_t)0xff0U)
#define CHUNK_MAP_BININD_INVALID CHUNK_MAP_BININD_MASK
#define CHUNK_MAP_FLAGS_MASK    ((size_t)0xcU)
#define CHUNK_MAP_DIRTY         ((size_t)0x8U)
#define CHUNK_MAP_UNZEROED      ((size_t)0x4U)
#define CHUNK_MAP_LARGE         ((size_t)0x2U)
#define CHUNK_MAP_ALLOCATED     ((size_t)0x1U)
#define CHUNK_MAP_KEY           CHUNK_MAP_ALLOCATED
};
typedef rb_tree(arena_chunk_map_t) arena_avail_tree_t;
typedef rb_tree(arena_chunk_map_t) arena_run_tree_t;

/* Arena chunk header. */
struct arena_chunk_s {
        /* Arena that owns the chunk. */
        arena_t         *arena;

        /* Linkage for the arena's chunks_dirty list. */
        ql_elm(arena_chunk_t) link_dirty;

        /*
         * True if the chunk is currently in the chunks_dirty list, due to
         * having at some point contained one or more dirty pages.  Removal
         * from chunks_dirty is lazy, so (dirtied && ndirty == 0) is possible.
         */
        bool            dirtied;

        /* Number of dirty pages. */
        size_t          ndirty;

        /*
         * Map of pages within chunk that keeps track of free/large/small.  The
         * first map_bias entries are omitted, since the chunk header does not
         * need to be tracked in the map.  This omission saves a header page
         * for common chunk sizes (e.g. 4 MiB).
         */
        arena_chunk_map_t map[1]; /* Dynamically sized. */
};
typedef rb_tree(arena_chunk_t) arena_chunk_tree_t;

struct arena_run_s {
        /* Bin this run is associated with. */
        arena_bin_t     *bin;

        /* Index of next region that has never been allocated, or nregs. */
        uint32_t        nextind;

        /* Number of free regions in run. */
        unsigned        nfree;
};

/*
 * Read-only information associated with each element of arena_t's bins array
 * is stored separately, partly to reduce memory usage (only one copy, rather
 * than one per arena), but mainly to avoid false cacheline sharing.
 *
 * Each run has the following layout:
 *
 *               /--------------------\
 *               | arena_run_t header |
 *               | ...                |
 * bitmap_offset | bitmap             |
 *               | ...                |
 *   ctx0_offset | ctx map            |
 *               | ...                |
 *               |--------------------|
 *               | redzone            |
 *   reg0_offset | region 0           |
 *               | redzone            |
 *               |--------------------| \
 *               | redzone            | |
 *               | region 1           |  > reg_interval
 *               | redzone            | /
 *               |--------------------|
 *               | ...                |
 *               | ...                |
 *               | ...                |
 *               |--------------------|
 *               | redzone            |
 *               | region nregs-1     |
 *               | redzone            |
 *               |--------------------|
 *               | alignment pad?     |
 *               \--------------------/
 *
 * reg_interval has at least the same minimum alignment as reg_size; this
 * preserves the alignment constraint that sa2u() depends on.  Alignment pad is
 * either 0 or redzone_size; it is present only if needed to align reg0_offset.
 */
struct arena_bin_info_s {
        /* Size of regions in a run for this bin's size class. */
        size_t          reg_size;

        /* Redzone size. */
        size_t          redzone_size;

        /* Interval between regions (reg_size + (redzone_size << 1)). */
        size_t          reg_interval;

        /* Total size of a run for this bin's size class. */
        size_t          run_size;

        /* Total number of regions in a run for this bin's size class. */
        uint32_t        nregs;

        /*
         * Offset of first bitmap_t element in a run header for this bin's size
         * class.
         */
        uint32_t        bitmap_offset;

        /*
         * Metadata used to manipulate bitmaps for runs associated with this
         * bin.
         */
        bitmap_info_t   bitmap_info;

        /*
         * Offset of first (prof_ctx_t *) in a run header for this bin's size
         * class, or 0 if (config_prof == false || opt_prof == false).
         */
        uint32_t        ctx0_offset;

        /* Offset of first region in a run for this bin's size class. */
        uint32_t        reg0_offset;
};

struct arena_bin_s {
        /*
         * All operations on runcur, runs, and stats require that lock be
         * locked.  Run allocation/deallocation are protected by the arena lock,
         * which may be acquired while holding one or more bin locks, but not
         * vise versa.
         */
        malloc_mutex_t  lock;

        /*
         * Current run being used to service allocations of this bin's size
         * class.
         */
        arena_run_t     *runcur;

        /*
         * Tree of non-full runs.  This tree is used when looking for an
         * existing run when runcur is no longer usable.  We choose the
         * non-full run that is lowest in memory; this policy tends to keep
         * objects packed well, and it can also help reduce the number of
         * almost-empty chunks.
         */
        arena_run_tree_t runs;

        /* Bin statistics. */
        malloc_bin_stats_t stats;
};

struct arena_s {
        /* This arena's index within the arenas array. */
        unsigned                ind;

        /*
         * Number of threads currently assigned to this arena.  This field is
         * protected by arenas_lock.
         */
        unsigned                nthreads;

        /*
         * There are three classes of arena operations from a locking
         * perspective:
         * 1) Thread asssignment (modifies nthreads) is protected by
         *    arenas_lock.
         * 2) Bin-related operations are protected by bin locks.
         * 3) Chunk- and run-related operations are protected by this mutex.
         */
        malloc_mutex_t          lock;

        arena_stats_t           stats;
        /*
         * List of tcaches for extant threads associated with this arena.
         * Stats from these are merged incrementally, and at exit.
         */
        ql_head(tcache_t)       tcache_ql;

        uint64_t                prof_accumbytes;

        /* List of dirty-page-containing chunks this arena manages. */
        ql_head(arena_chunk_t)  chunks_dirty;

        /*
         * In order to avoid rapid chunk allocation/deallocation when an arena
         * oscillates right on the cusp of needing a new chunk, cache the most
         * recently freed chunk.  The spare is left in the arena's chunk trees
         * until it is deleted.
         *
         * There is one spare chunk per arena, rather than one spare total, in
         * order to avoid interactions between multiple threads that could make
         * a single spare inadequate.
         */
        arena_chunk_t           *spare;

        /* Number of pages in active runs. */
        size_t                  nactive;

        /*
         * Current count of pages within unused runs that are potentially
         * dirty, and for which madvise(... MADV_DONTNEED) has not been called.
         * By tracking this, we can institute a limit on how much dirty unused
         * memory is mapped for each arena.
         */
        size_t                  ndirty;

        /*
         * Approximate number of pages being purged.  It is possible for
         * multiple threads to purge dirty pages concurrently, and they use
         * npurgatory to indicate the total number of pages all threads are
         * attempting to purge.
         */
        size_t                  npurgatory;

        /*
         * Size/address-ordered trees of this arena's available runs.  The trees
         * are used for first-best-fit run allocation.  The dirty tree contains
         * runs with dirty pages (i.e. very likely to have been touched and
         * therefore have associated physical pages), whereas the clean tree
         * contains runs with pages that either have no associated physical
         * pages, or have pages that the kernel may recycle at any time due to
         * previous madvise(2) calls.  The dirty tree is used in preference to
         * the clean tree for allocations, because using dirty pages reduces
         * the amount of dirty purging necessary to keep the active:dirty page
         * ratio below the purge threshold.
         */
        arena_avail_tree_t      runs_avail_clean;
        arena_avail_tree_t      runs_avail_dirty;

        /* bins is used to store trees of free regions. */
        arena_bin_t             bins[NBINS];
};

#endif /* JEMALLOC_H_STRUCTS */
/******************************************************************************/
#ifdef JEMALLOC_H_EXTERNS

extern ssize_t  opt_lg_dirty_mult;
/*
 * small_size2bin is a compact lookup table that rounds request sizes up to
 * size classes.  In order to reduce cache footprint, the table is compressed,
 * and all accesses are via the SMALL_SIZE2BIN macro.
 */
extern uint8_t const    small_size2bin[];
#define SMALL_SIZE2BIN(s)       (small_size2bin[(s-1) >> LG_TINY_MIN])

extern arena_bin_info_t arena_bin_info[NBINS];

/* Number of large size classes. */
#define                 nlclasses (chunk_npages - map_bias)

void    arena_purge_all(arena_t *arena);
void    arena_prof_accum(arena_t *arena, uint64_t accumbytes);
void    arena_tcache_fill_small(arena_t *arena, tcache_bin_t *tbin,
    size_t binind, uint64_t prof_accumbytes);
void    arena_alloc_junk_small(void *ptr, arena_bin_info_t *bin_info,
    bool zero);
void    arena_dalloc_junk_small(void *ptr, arena_bin_info_t *bin_info);
void    *arena_malloc_small(arena_t *arena, size_t size, bool zero);
void    *arena_malloc_large(arena_t *arena, size_t size, bool zero);
void    *arena_palloc(arena_t *arena, size_t size, size_t alignment, bool zero);
void    arena_prof_promoted(const void *ptr, size_t size);
void    arena_dalloc_bin_locked(arena_t *arena, arena_chunk_t *chunk, void *ptr,
    arena_chunk_map_t *mapelm);
void    arena_dalloc_bin(arena_t *arena, arena_chunk_t *chunk, void *ptr,
    size_t pageind, arena_chunk_map_t *mapelm);
void    arena_dalloc_small(arena_t *arena, arena_chunk_t *chunk, void *ptr,
    size_t pageind);
void    arena_dalloc_large_locked(arena_t *arena, arena_chunk_t *chunk,
    void *ptr);
void    arena_dalloc_large(arena_t *arena, arena_chunk_t *chunk, void *ptr);
void    arena_stats_merge(arena_t *arena, size_t *nactive, size_t *ndirty,
    arena_stats_t *astats, malloc_bin_stats_t *bstats,
    malloc_large_stats_t *lstats);
void    *arena_ralloc_no_move(void *ptr, size_t oldsize, size_t size,
    size_t extra, bool zero);
void    *arena_ralloc(void *ptr, size_t oldsize, size_t size, size_t extra,
    size_t alignment, bool zero, bool try_tcache);
bool    arena_new(arena_t *arena, unsigned ind);
void    arena_boot(void);
void    arena_prefork(arena_t *arena);
void    arena_postfork_parent(arena_t *arena);
void    arena_postfork_child(arena_t *arena);

#endif /* JEMALLOC_H_EXTERNS */
/******************************************************************************/
#ifdef JEMALLOC_H_INLINES

#ifndef JEMALLOC_ENABLE_INLINE
arena_chunk_map_t       *arena_mapp_get(arena_chunk_t *chunk, size_t pageind);
size_t  *arena_mapbitsp_get(arena_chunk_t *chunk, size_t pageind);
size_t  arena_mapbits_get(arena_chunk_t *chunk, size_t pageind);
size_t  arena_mapbits_unallocated_size_get(arena_chunk_t *chunk,
    size_t pageind);
size_t  arena_mapbits_large_size_get(arena_chunk_t *chunk, size_t pageind);
size_t  arena_mapbits_small_runind_get(arena_chunk_t *chunk, size_t pageind);
size_t  arena_mapbits_binind_get(arena_chunk_t *chunk, size_t pageind);
size_t  arena_mapbits_dirty_get(arena_chunk_t *chunk, size_t pageind);
size_t  arena_mapbits_unzeroed_get(arena_chunk_t *chunk, size_t pageind);
size_t  arena_mapbits_large_get(arena_chunk_t *chunk, size_t pageind);
size_t  arena_mapbits_allocated_get(arena_chunk_t *chunk, size_t pageind);
void    arena_mapbits_unallocated_set(arena_chunk_t *chunk, size_t pageind,
    size_t size, size_t flags);
void    arena_mapbits_unallocated_size_set(arena_chunk_t *chunk, size_t pageind,
    size_t size);
void    arena_mapbits_large_set(arena_chunk_t *chunk, size_t pageind,
    size_t size, size_t flags);
void    arena_mapbits_large_binind_set(arena_chunk_t *chunk, size_t pageind,
    size_t binind);
void    arena_mapbits_small_set(arena_chunk_t *chunk, size_t pageind,
    size_t runind, size_t binind, size_t flags);
void    arena_mapbits_unzeroed_set(arena_chunk_t *chunk, size_t pageind,
    size_t unzeroed);
size_t  arena_ptr_small_binind_get(const void *ptr, size_t mapbits);
size_t  arena_bin_index(arena_t *arena, arena_bin_t *bin);
unsigned        arena_run_regind(arena_run_t *run, arena_bin_info_t *bin_info,
    const void *ptr);
prof_ctx_t      *arena_prof_ctx_get(const void *ptr);
void    arena_prof_ctx_set(const void *ptr, prof_ctx_t *ctx);
void    *arena_malloc(arena_t *arena, size_t size, bool zero, bool try_tcache);
size_t  arena_salloc(const void *ptr, bool demote);
void    arena_dalloc(arena_t *arena, arena_chunk_t *chunk, void *ptr,
    bool try_tcache);
#endif

#if (defined(JEMALLOC_ENABLE_INLINE) || defined(JEMALLOC_ARENA_C_))
#  ifdef JEMALLOC_ARENA_INLINE_A
JEMALLOC_INLINE arena_chunk_map_t *
arena_mapp_get(arena_chunk_t *chunk, size_t pageind)
{

        assert(pageind >= map_bias);
        assert(pageind < chunk_npages);

        return (&chunk->map[pageind-map_bias]);
}

JEMALLOC_INLINE size_t *
arena_mapbitsp_get(arena_chunk_t *chunk, size_t pageind)
{

        return (&arena_mapp_get(chunk, pageind)->bits);
}

JEMALLOC_INLINE size_t
arena_mapbits_get(arena_chunk_t *chunk, size_t pageind)
{

        return (*arena_mapbitsp_get(chunk, pageind));
}

JEMALLOC_INLINE size_t
arena_mapbits_unallocated_size_get(arena_chunk_t *chunk, size_t pageind)
{
        size_t mapbits;

        mapbits = arena_mapbits_get(chunk, pageind);
        assert((mapbits & (CHUNK_MAP_LARGE|CHUNK_MAP_ALLOCATED)) == 0);
        return (mapbits & ~PAGE_MASK);
}

JEMALLOC_INLINE size_t
arena_mapbits_large_size_get(arena_chunk_t *chunk, size_t pageind)
{
        size_t mapbits;

        mapbits = arena_mapbits_get(chunk, pageind);
        assert((mapbits & (CHUNK_MAP_LARGE|CHUNK_MAP_ALLOCATED)) ==
            (CHUNK_MAP_LARGE|CHUNK_MAP_ALLOCATED));
        return (mapbits & ~PAGE_MASK);
}

JEMALLOC_INLINE size_t
arena_mapbits_small_runind_get(arena_chunk_t *chunk, size_t pageind)
{
        size_t mapbits;

        mapbits = arena_mapbits_get(chunk, pageind);
        assert((mapbits & (CHUNK_MAP_LARGE|CHUNK_MAP_ALLOCATED)) ==
            CHUNK_MAP_ALLOCATED);
        return (mapbits >> LG_PAGE);
}

JEMALLOC_INLINE size_t
arena_mapbits_binind_get(arena_chunk_t *chunk, size_t pageind)
{
        size_t mapbits;
        size_t binind;

        mapbits = arena_mapbits_get(chunk, pageind);
        binind = (mapbits & CHUNK_MAP_BININD_MASK) >> CHUNK_MAP_BININD_SHIFT;
        assert(binind < NBINS || binind == BININD_INVALID);
        return (binind);
}

JEMALLOC_INLINE size_t
arena_mapbits_dirty_get(arena_chunk_t *chunk, size_t pageind)
{
        size_t mapbits;

        mapbits = arena_mapbits_get(chunk, pageind);
        return (mapbits & CHUNK_MAP_DIRTY);
}

JEMALLOC_INLINE size_t
arena_mapbits_unzeroed_get(arena_chunk_t *chunk, size_t pageind)
{
        size_t mapbits;

        mapbits = arena_mapbits_get(chunk, pageind);
        return (mapbits & CHUNK_MAP_UNZEROED);
}

JEMALLOC_INLINE size_t
arena_mapbits_large_get(arena_chunk_t *chunk, size_t pageind)
{
        size_t mapbits;

        mapbits = arena_mapbits_get(chunk, pageind);
        return (mapbits & CHUNK_MAP_LARGE);
}

JEMALLOC_INLINE size_t
arena_mapbits_allocated_get(arena_chunk_t *chunk, size_t pageind)
{
        size_t mapbits;

        mapbits = arena_mapbits_get(chunk, pageind);
        return (mapbits & CHUNK_MAP_ALLOCATED);
}

JEMALLOC_INLINE void
arena_mapbits_unallocated_set(arena_chunk_t *chunk, size_t pageind, size_t size,
    size_t flags)
{
        size_t *mapbitsp;

        mapbitsp = arena_mapbitsp_get(chunk, pageind);
        assert((size & PAGE_MASK) == 0);
        assert((flags & ~CHUNK_MAP_FLAGS_MASK) == 0);
        assert((flags & (CHUNK_MAP_DIRTY|CHUNK_MAP_UNZEROED)) == flags);
        *mapbitsp = size | CHUNK_MAP_BININD_INVALID | flags;
}

JEMALLOC_INLINE void
arena_mapbits_unallocated_size_set(arena_chunk_t *chunk, size_t pageind,
    size_t size)
{
        size_t *mapbitsp;

        mapbitsp = arena_mapbitsp_get(chunk, pageind);
        assert((size & PAGE_MASK) == 0);
        assert((*mapbitsp & (CHUNK_MAP_LARGE|CHUNK_MAP_ALLOCATED)) == 0);
        *mapbitsp = size | (*mapbitsp & PAGE_MASK);
}

JEMALLOC_INLINE void
arena_mapbits_large_set(arena_chunk_t *chunk, size_t pageind, size_t size,
    size_t flags)
{
        size_t *mapbitsp;
        size_t unzeroed;

        mapbitsp = arena_mapbitsp_get(chunk, pageind);
        assert((size & PAGE_MASK) == 0);
        assert((flags & CHUNK_MAP_DIRTY) == flags);
        unzeroed = *mapbitsp & CHUNK_MAP_UNZEROED; /* Preserve unzeroed. */
        *mapbitsp = size | CHUNK_MAP_BININD_INVALID | flags | unzeroed |
            CHUNK_MAP_LARGE | CHUNK_MAP_ALLOCATED;
}

JEMALLOC_INLINE void
arena_mapbits_large_binind_set(arena_chunk_t *chunk, size_t pageind,
    size_t binind)
{
        size_t *mapbitsp;

        assert(binind <= BININD_INVALID);
        mapbitsp = arena_mapbitsp_get(chunk, pageind);
        assert(arena_mapbits_large_size_get(chunk, pageind) == PAGE);
        *mapbitsp = (*mapbitsp & ~CHUNK_MAP_BININD_MASK) | (binind <<
            CHUNK_MAP_BININD_SHIFT);
}

JEMALLOC_INLINE void
arena_mapbits_small_set(arena_chunk_t *chunk, size_t pageind, size_t runind,
    size_t binind, size_t flags)
{
        size_t *mapbitsp;
        size_t unzeroed;

        assert(binind < BININD_INVALID);
        mapbitsp = arena_mapbitsp_get(chunk, pageind);
        assert(pageind - runind >= map_bias);
        assert((flags & CHUNK_MAP_DIRTY) == flags);
        unzeroed = *mapbitsp & CHUNK_MAP_UNZEROED; /* Preserve unzeroed. */
        *mapbitsp = (runind << LG_PAGE) | (binind << CHUNK_MAP_BININD_SHIFT) |
            flags | unzeroed | CHUNK_MAP_ALLOCATED;
}

JEMALLOC_INLINE void
arena_mapbits_unzeroed_set(arena_chunk_t *chunk, size_t pageind,
    size_t unzeroed)
{
        size_t *mapbitsp;

        mapbitsp = arena_mapbitsp_get(chunk, pageind);
        *mapbitsp = (*mapbitsp & ~CHUNK_MAP_UNZEROED) | unzeroed;
}

JEMALLOC_INLINE size_t
arena_ptr_small_binind_get(const void *ptr, size_t mapbits)
{
        size_t binind;

        binind = (mapbits & CHUNK_MAP_BININD_MASK) >> CHUNK_MAP_BININD_SHIFT;

        if (config_debug) {
                arena_chunk_t *chunk;
                arena_t *arena;
                size_t pageind;
                size_t actual_mapbits;
                arena_run_t *run;
                arena_bin_t *bin;
                size_t actual_binind;
                arena_bin_info_t *bin_info;

                assert(binind != BININD_INVALID);
                assert(binind < NBINS);
                chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
                arena = chunk->arena;
                pageind = ((uintptr_t)ptr - (uintptr_t)chunk) >> LG_PAGE;
                actual_mapbits = arena_mapbits_get(chunk, pageind);
                assert(mapbits == actual_mapbits);
                assert(arena_mapbits_large_get(chunk, pageind) == 0);
                assert(arena_mapbits_allocated_get(chunk, pageind) != 0);
                run = (arena_run_t *)((uintptr_t)chunk + (uintptr_t)((pageind -
                    (actual_mapbits >> LG_PAGE)) << LG_PAGE));
                bin = run->bin;
                actual_binind = bin - arena->bins;
                assert(binind == actual_binind);
                bin_info = &arena_bin_info[actual_binind];
                assert(((uintptr_t)ptr - ((uintptr_t)run +
                    (uintptr_t)bin_info->reg0_offset)) % bin_info->reg_interval
                    == 0);
        }

        return (binind);
}
#  endif /* JEMALLOC_ARENA_INLINE_A */

#  ifdef JEMALLOC_ARENA_INLINE_B
JEMALLOC_INLINE size_t
arena_bin_index(arena_t *arena, arena_bin_t *bin)
{
        size_t binind = bin - arena->bins;
        assert(binind < NBINS);
        return (binind);
}

JEMALLOC_INLINE unsigned
arena_run_regind(arena_run_t *run, arena_bin_info_t *bin_info, const void *ptr)
{
        unsigned shift, diff, regind;
        size_t interval;

        /*
         * Freeing a pointer lower than region zero can cause assertion
         * failure.
         */
        assert((uintptr_t)ptr >= (uintptr_t)run +
            (uintptr_t)bin_info->reg0_offset);

        /*
         * Avoid doing division with a variable divisor if possible.  Using
         * actual division here can reduce allocator throughput by over 20%!
         */
        diff = (unsigned)((uintptr_t)ptr - (uintptr_t)run -
            bin_info->reg0_offset);

        /* Rescale (factor powers of 2 out of the numerator and denominator). */
        interval = bin_info->reg_interval;
        shift = ffs(interval) - 1;
        diff >>= shift;
        interval >>= shift;

        if (interval == 1) {
                /* The divisor was a power of 2. */
                regind = diff;
        } else {
                /*
                 * To divide by a number D that is not a power of two we
                 * multiply by (2^21 / D) and then right shift by 21 positions.
                 *
                 *   X / D
                 *
                 * becomes
                 *
                 *   (X * interval_invs[D - 3]) >> SIZE_INV_SHIFT
                 *
                 * We can omit the first three elements, because we never
                 * divide by 0, and 1 and 2 are both powers of two, which are
                 * handled above.
                 */
#define SIZE_INV_SHIFT  ((sizeof(unsigned) << 3) - LG_RUN_MAXREGS)
#define SIZE_INV(s)     (((1U << SIZE_INV_SHIFT) / (s)) + 1)
                static const unsigned interval_invs[] = {
                    SIZE_INV(3),
                    SIZE_INV(4), SIZE_INV(5), SIZE_INV(6), SIZE_INV(7),
                    SIZE_INV(8), SIZE_INV(9), SIZE_INV(10), SIZE_INV(11),
                    SIZE_INV(12), SIZE_INV(13), SIZE_INV(14), SIZE_INV(15),
                    SIZE_INV(16), SIZE_INV(17), SIZE_INV(18), SIZE_INV(19),
                    SIZE_INV(20), SIZE_INV(21), SIZE_INV(22), SIZE_INV(23),
                    SIZE_INV(24), SIZE_INV(25), SIZE_INV(26), SIZE_INV(27),
                    SIZE_INV(28), SIZE_INV(29), SIZE_INV(30), SIZE_INV(31)
                };

                if (interval <= ((sizeof(interval_invs) / sizeof(unsigned)) +
                    2)) {
                        regind = (diff * interval_invs[interval - 3]) >>
                            SIZE_INV_SHIFT;
                } else
                        regind = diff / interval;
#undef SIZE_INV
#undef SIZE_INV_SHIFT
        }
        assert(diff == regind * interval);
        assert(regind < bin_info->nregs);

        return (regind);
}

JEMALLOC_INLINE prof_ctx_t *
arena_prof_ctx_get(const void *ptr)
{
        prof_ctx_t *ret;
        arena_chunk_t *chunk;
        size_t pageind, mapbits;

        cassert(config_prof);
        assert(ptr != NULL);
        assert(CHUNK_ADDR2BASE(ptr) != ptr);

        chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
        pageind = ((uintptr_t)ptr - (uintptr_t)chunk) >> LG_PAGE;
        mapbits = arena_mapbits_get(chunk, pageind);
        assert((mapbits & CHUNK_MAP_ALLOCATED) != 0);
        if ((mapbits & CHUNK_MAP_LARGE) == 0) {
                if (prof_promote)
                        ret = (prof_ctx_t *)(uintptr_t)1U;
                else {
                        arena_run_t *run = (arena_run_t *)((uintptr_t)chunk +
                            (uintptr_t)((pageind - (mapbits >> LG_PAGE)) <<
                            LG_PAGE));
                        size_t binind = arena_ptr_small_binind_get(ptr,
                            mapbits);
                        arena_bin_info_t *bin_info = &arena_bin_info[binind];
                        unsigned regind;

                        regind = arena_run_regind(run, bin_info, ptr);
                        ret = *(prof_ctx_t **)((uintptr_t)run +
                            bin_info->ctx0_offset + (regind *
                            sizeof(prof_ctx_t *)));
                }
        } else
                ret = arena_mapp_get(chunk, pageind)->prof_ctx;

        return (ret);
}

JEMALLOC_INLINE void
arena_prof_ctx_set(const void *ptr, prof_ctx_t *ctx)
{
        arena_chunk_t *chunk;
        size_t pageind, mapbits;

        cassert(config_prof);
        assert(ptr != NULL);
        assert(CHUNK_ADDR2BASE(ptr) != ptr);

        chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
        pageind = ((uintptr_t)ptr - (uintptr_t)chunk) >> LG_PAGE;
        mapbits = arena_mapbits_get(chunk, pageind);
        assert((mapbits & CHUNK_MAP_ALLOCATED) != 0);
        if ((mapbits & CHUNK_MAP_LARGE) == 0) {
                if (prof_promote == false) {
                        arena_run_t *run = (arena_run_t *)((uintptr_t)chunk +
                            (uintptr_t)((pageind - (mapbits >> LG_PAGE)) <<
                            LG_PAGE));
                        size_t binind;
                        arena_bin_info_t *bin_info;
                        unsigned regind;

                        binind = arena_ptr_small_binind_get(ptr, mapbits);
                        bin_info = &arena_bin_info[binind];
                        regind = arena_run_regind(run, bin_info, ptr);

                        *((prof_ctx_t **)((uintptr_t)run + bin_info->ctx0_offset
                            + (regind * sizeof(prof_ctx_t *)))) = ctx;
                } else
                        assert((uintptr_t)ctx == (uintptr_t)1U);
        } else
                arena_mapp_get(chunk, pageind)->prof_ctx = ctx;
}

JEMALLOC_INLINE void *
arena_malloc(arena_t *arena, size_t size, bool zero, bool try_tcache)
{
        tcache_t *tcache;

        assert(size != 0);
        assert(size <= arena_maxclass);

        if (size <= SMALL_MAXCLASS) {
                if (try_tcache && (tcache = tcache_get(true)) != NULL)
                        return (tcache_alloc_small(tcache, size, zero));
                else {
                        return (arena_malloc_small(choose_arena(arena), size,
                            zero));
                }
        } else {
                /*
                 * Initialize tcache after checking size in order to avoid
                 * infinite recursion during tcache initialization.
                 */
                if (try_tcache && size <= tcache_maxclass && (tcache =
                    tcache_get(true)) != NULL)
                        return (tcache_alloc_large(tcache, size, zero));
                else {
                        return (arena_malloc_large(choose_arena(arena), size,
                            zero));
                }
        }
}

/* Return the size of the allocation pointed to by ptr. */
JEMALLOC_INLINE size_t
arena_salloc(const void *ptr, bool demote)
{
        size_t ret;
        arena_chunk_t *chunk;
        size_t pageind, binind;

        assert(ptr != NULL);
        assert(CHUNK_ADDR2BASE(ptr) != ptr);

        chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
        pageind = ((uintptr_t)ptr - (uintptr_t)chunk) >> LG_PAGE;
        assert(arena_mapbits_allocated_get(chunk, pageind) != 0);
        binind = arena_mapbits_binind_get(chunk, pageind);
        if (binind == BININD_INVALID || (config_prof && demote == false &&
            prof_promote && arena_mapbits_large_get(chunk, pageind) != 0)) {
                /*
                 * Large allocation.  In the common case (demote == true), and
                 * as this is an inline function, most callers will only end up
                 * looking at binind to determine that ptr is a small
                 * allocation.
                 */
                assert(((uintptr_t)ptr & PAGE_MASK) == 0);
                ret = arena_mapbits_large_size_get(chunk, pageind);
                assert(ret != 0);
                assert(pageind + (ret>>LG_PAGE) <= chunk_npages);
                assert(ret == PAGE || arena_mapbits_large_size_get(chunk,
                    pageind+(ret>>LG_PAGE)-1) == 0);
                assert(binind == arena_mapbits_binind_get(chunk,
                    pageind+(ret>>LG_PAGE)-1));
                assert(arena_mapbits_dirty_get(chunk, pageind) ==
                    arena_mapbits_dirty_get(chunk, pageind+(ret>>LG_PAGE)-1));
        } else {
                /*
                 * Small allocation (possibly promoted to a large object due to
                 * prof_promote).
                 */
                assert(arena_mapbits_large_get(chunk, pageind) != 0 ||
                    arena_ptr_small_binind_get(ptr, arena_mapbits_get(chunk,
                    pageind)) == binind);
                ret = arena_bin_info[binind].reg_size;
        }

        return (ret);
}

JEMALLOC_INLINE void
arena_dalloc(arena_t *arena, arena_chunk_t *chunk, void *ptr, bool try_tcache)
{
        size_t pageind, mapbits;
        tcache_t *tcache;

        assert(arena != NULL);
        assert(chunk->arena == arena);
        assert(ptr != NULL);
        assert(CHUNK_ADDR2BASE(ptr) != ptr);

        pageind = ((uintptr_t)ptr - (uintptr_t)chunk) >> LG_PAGE;
        mapbits = arena_mapbits_get(chunk, pageind);
        assert(arena_mapbits_allocated_get(chunk, pageind) != 0);
        if ((mapbits & CHUNK_MAP_LARGE) == 0) {
                /* Small allocation. */
                if (try_tcache && (tcache = tcache_get(false)) != NULL) {
                        size_t binind;

                        binind = arena_ptr_small_binind_get(ptr, mapbits);
                        tcache_dalloc_small(tcache, ptr, binind);
                } else
                        arena_dalloc_small(arena, chunk, ptr, pageind);
        } else {
                size_t size = arena_mapbits_large_size_get(chunk, pageind);

                assert(((uintptr_t)ptr & PAGE_MASK) == 0);

                if (try_tcache && size <= tcache_maxclass && (tcache =
                    tcache_get(false)) != NULL) {
                        tcache_dalloc_large(tcache, ptr, size);
                } else
                        arena_dalloc_large(arena, chunk, ptr);
        }
}
#  endif /* JEMALLOC_ARENA_INLINE_B */
#endif

#endif /* JEMALLOC_H_INLINES */
/******************************************************************************/