arena.h

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/******************************************************************************/
#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 3, there can be no less than 8 times
 * as many active pages as dirty pages.
 */
#define LG_DIRTY_MULT_DEFAULT 3

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 tree.
 * 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;
typedef ql_head(arena_chunk_map_t) arena_chunk_mapelms_t;

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

 /* Linkage for tree of arena chunks that contain dirty runs. */
 rb_node(arena_chunk_t) dirty_link;

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

 /* Number of available runs. */
 size_t nruns_avail;

 /*
 * Number of available run adjacencies that purging could coalesce.
 * Clean and dirty available runs are not coalesced, which causes
 * virtual memory fragmentation. The ratio of
 * (nruns_avail-nruns_adjac):nruns_adjac is used for tracking this
 * fragmentation.
 */
 size_t nruns_adjac;

 /*
 * 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;

 dss_prec_t dss_prec;

 /* Tree of dirty-page-containing chunks this arena manages. */
 arena_chunk_tree_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.
 */
 arena_avail_tree_t runs_avail;

 /* 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_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);
#ifdef JEMALLOC_JET
typedef void (arena_redzone_corruption_t)(void *, size_t, bool, size_t,
 uint8_t);
extern arena_redzone_corruption_t *arena_redzone_corruption;
typedef void (arena_dalloc_junk_small_t)(void *, arena_bin_info_t *);
extern arena_dalloc_junk_small_t *arena_dalloc_junk_small;
#else
void arena_dalloc_junk_small(void *ptr, arena_bin_info_t *bin_info);
#endif
void arena_quarantine_junk_small(void *ptr, size_t usize);
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);
#ifdef JEMALLOC_JET
typedef void (arena_dalloc_junk_large_t)(void *, size_t);
extern arena_dalloc_junk_large_t *arena_dalloc_junk_large;
#endif
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);
#ifdef JEMALLOC_JET
typedef void (arena_ralloc_junk_large_t)(void *, size_t, size_t);
extern arena_ralloc_junk_large_t *arena_ralloc_junk_large;
#endif
bool arena_ralloc_no_move(void *ptr, size_t oldsize, size_t size,
 size_t extra, bool zero);
void *arena_ralloc(arena_t *arena, void *ptr, size_t oldsize, size_t size,
 size_t extra, size_t alignment, bool zero, bool try_tcache_alloc,
 bool try_tcache_dalloc);
dss_prec_t arena_dss_prec_get(arena_t *arena);
void arena_dss_prec_set(arena_t *arena, dss_prec_t dss_prec);
void arena_stats_merge(arena_t *arena, const char **dss, size_t *nactive,
 size_t *ndirty, arena_stats_t *astats, malloc_bin_stats_t *bstats,
 malloc_large_stats_t *lstats);
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_mapbitsp_read(size_t *mapbitsp);
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_mapbitsp_write(size_t *mapbitsp, size_t mapbits);
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);
bool arena_prof_accum_impl(arena_t *arena, uint64_t accumbytes);
bool arena_prof_accum_locked(arena_t *arena, uint64_t accumbytes);
bool arena_prof_accum(arena_t *arena, uint64_t accumbytes);
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, size_t usize, 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_ALWAYS_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_ALWAYS_INLINE size_t *
arena_mapbitsp_get(arena_chunk_t *chunk, size_t pageind)
{

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

JEMALLOC_ALWAYS_INLINE size_t
arena_mapbitsp_read(size_t *mapbitsp)
{

 return (*mapbitsp);
}

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

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

JEMALLOC_ALWAYS_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_ALWAYS_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_ALWAYS_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_ALWAYS_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_ALWAYS_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_ALWAYS_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_ALWAYS_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_ALWAYS_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_ALWAYS_INLINE void
arena_mapbitsp_write(size_t *mapbitsp, size_t mapbits)
{

 *mapbitsp = mapbits;
}

JEMALLOC_ALWAYS_INLINE void
arena_mapbits_unallocated_set(arena_chunk_t *chunk, size_t pageind, size_t size,
 size_t flags)
{
 size_t *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);
 arena_mapbitsp_write(mapbitsp, size | CHUNK_MAP_BININD_INVALID | flags);
}

JEMALLOC_ALWAYS_INLINE void
arena_mapbits_unallocated_size_set(arena_chunk_t *chunk, size_t pageind,
 size_t size)
{
 size_t *mapbitsp = arena_mapbitsp_get(chunk, pageind);
 size_t mapbits = arena_mapbitsp_read(mapbitsp);

 assert((size & PAGE_MASK) == 0);
 assert((mapbits & (CHUNK_MAP_LARGE|CHUNK_MAP_ALLOCATED)) == 0);
 arena_mapbitsp_write(mapbitsp, size | (mapbits & PAGE_MASK));
}

JEMALLOC_ALWAYS_INLINE void
arena_mapbits_large_set(arena_chunk_t *chunk, size_t pageind, size_t size,
 size_t flags)
{
 size_t *mapbitsp = arena_mapbitsp_get(chunk, pageind);
 size_t mapbits = arena_mapbitsp_read(mapbitsp);
 size_t unzeroed;

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

JEMALLOC_ALWAYS_INLINE void
arena_mapbits_large_binind_set(arena_chunk_t *chunk, size_t pageind,
 size_t binind)
{
 size_t *mapbitsp = arena_mapbitsp_get(chunk, pageind);
 size_t mapbits = arena_mapbitsp_read(mapbitsp);

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

JEMALLOC_ALWAYS_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 = arena_mapbitsp_get(chunk, pageind);
 size_t mapbits = arena_mapbitsp_read(mapbitsp);
 size_t unzeroed;

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

JEMALLOC_ALWAYS_INLINE void
arena_mapbits_unzeroed_set(arena_chunk_t *chunk, size_t pageind,
 size_t unzeroed)
{
 size_t *mapbitsp = arena_mapbitsp_get(chunk, pageind);
 size_t mapbits = arena_mapbitsp_read(mapbitsp);

 arena_mapbitsp_write(mapbitsp, (mapbits & ~CHUNK_MAP_UNZEROED) |
 unzeroed);
}

JEMALLOC_INLINE bool
arena_prof_accum_impl(arena_t *arena, uint64_t accumbytes)
{

 cassert(config_prof);
 assert(prof_interval != 0);

 arena->prof_accumbytes += accumbytes;
 if (arena->prof_accumbytes >= prof_interval) {
 arena->prof_accumbytes -= prof_interval;
 return (true);
 }
 return (false);
}

JEMALLOC_INLINE bool
arena_prof_accum_locked(arena_t *arena, uint64_t accumbytes)
{

 cassert(config_prof);

 if (prof_interval == 0)
 return (false);
 return (arena_prof_accum_impl(arena, accumbytes));
}

JEMALLOC_INLINE bool
arena_prof_accum(arena_t *arena, uint64_t accumbytes)
{

 cassert(config_prof);

 if (prof_interval == 0)
 return (false);

 {
 bool ret;

 malloc_mutex_lock(&arena->lock);
 ret = arena_prof_accum_impl(arena, accumbytes);
 malloc_mutex_unlock(&arena->lock);
 return (ret);
 }
}

JEMALLOC_ALWAYS_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, size_t usize, prof_ctx_t *ctx)
{
 arena_chunk_t *chunk;
 size_t pageind;

 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;
 assert(arena_mapbits_allocated_get(chunk, pageind) != 0);

 if (usize > SMALL_MAXCLASS || (prof_promote &&
 ((uintptr_t)ctx != (uintptr_t)1U || arena_mapbits_large_get(chunk,
 pageind) != 0))) {
 assert(arena_mapbits_large_get(chunk, pageind) != 0);
 arena_mapp_get(chunk, pageind)->prof_ctx = ctx;
 } else {
 assert(arena_mapbits_large_get(chunk, pageind) == 0);
 if (prof_promote == false) {
 size_t mapbits = arena_mapbits_get(chunk, pageind);
 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;
 }
 }
}

JEMALLOC_ALWAYS_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_ALWAYS_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_ALWAYS_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 */
/******************************************************************************/