#define JEMALLOC_TCACHE_C_
#include "jemalloc/internal/jemalloc_internal.h"
/******************************************************************************/
/* Data. */
malloc_tsd_data(, tcache, tcache_t *, NULL)
malloc_tsd_data(, tcache_enabled, tcache_enabled_t, tcache_enabled_default)
bool opt_tcache = true;
ssize_t opt_lg_tcache_max = LG_TCACHE_MAXCLASS_DEFAULT;
tcache_bin_info_t *tcache_bin_info;
static unsigned stack_nelms; /* Total stack elms per tcache. */
size_t nhbins;
size_t tcache_maxclass;
/******************************************************************************/
size_t tcache_salloc(const void *ptr)
{
return (arena_salloc(ptr, false));
}
void
tcache_event_hard(tcache_t *tcache)
{
size_t binind = tcache->next_gc_bin;
tcache_bin_t *tbin = &tcache->tbins[binind];
tcache_bin_info_t *tbin_info = &tcache_bin_info[binind];
if (tbin->low_water > 0) {
/*
* Flush (ceiling) 3/4 of the objects below the low water mark.
*/
if (binind < NBINS) {
tcache_bin_flush_small(tbin, binind, tbin->ncached -
tbin->low_water + (tbin->low_water >> 2), tcache);
} else {
tcache_bin_flush_large(tbin, binind, tbin->ncached -
tbin->low_water + (tbin->low_water >> 2), tcache);
}
/*
* Reduce fill count by 2X. Limit lg_fill_div such that the
* fill count is always at least 1.
*/
if ((tbin_info->ncached_max >> (tbin->lg_fill_div+1)) >= 1)
tbin->lg_fill_div++;
} else if (tbin->low_water < 0) {
/*
* Increase fill count by 2X. Make sure lg_fill_div stays
* greater than 0.
*/
if (tbin->lg_fill_div > 1)
tbin->lg_fill_div--;
}
tbin->low_water = tbin->ncached;
tcache->next_gc_bin++;
if (tcache->next_gc_bin == nhbins)
tcache->next_gc_bin = 0;
tcache->ev_cnt = 0;
}
void *
tcache_alloc_small_hard(tcache_t *tcache, tcache_bin_t *tbin, size_t binind)
{
void *ret;
arena_tcache_fill_small(tcache->arena, tbin, binind,
config_prof ? tcache->prof_accumbytes : 0);
if (config_prof)
tcache->prof_accumbytes = 0;
ret = tcache_alloc_easy(tbin);
return (ret);
}
void
tcache_bin_flush_small(tcache_bin_t *tbin, size_t binind, unsigned rem,
tcache_t *tcache)
{
void *ptr;
unsigned i, nflush, ndeferred;
bool merged_stats = false;
assert(binind < NBINS);
assert(rem <= tbin->ncached);
for (nflush = tbin->ncached - rem; nflush > 0; nflush = ndeferred) {
/* Lock the arena bin associated with the first object. */
arena_chunk_t *chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(
tbin->avail[0]);
arena_t *arena = chunk->arena;
arena_bin_t *bin = &arena->bins[binind];
if (config_prof && arena == tcache->arena) {
if (arena_prof_accum(arena, tcache->prof_accumbytes))
prof_idump();
tcache->prof_accumbytes = 0;
}
malloc_mutex_lock(&bin->lock);
if (config_stats && arena == tcache->arena) {
assert(merged_stats == false);
merged_stats = true;
bin->stats.nflushes++;
bin->stats.nrequests += tbin->tstats.nrequests;
tbin->tstats.nrequests = 0;
}
ndeferred = 0;
for (i = 0; i < nflush; i++) {
ptr = tbin->avail[i];
assert(ptr != NULL);
chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
if (chunk->arena == arena) {
size_t pageind = ((uintptr_t)ptr -
(uintptr_t)chunk) >> LG_PAGE;
arena_chunk_map_t *mapelm =
arena_mapp_get(chunk, pageind);
if (config_fill && opt_junk) {
arena_alloc_junk_small(ptr,
&arena_bin_info[binind], true);
}
arena_dalloc_bin_locked(arena, chunk, ptr,
mapelm);
} else {
/*
* This object was allocated via a different
* arena bin than the one that is currently
* locked. Stash the object, so that it can be
* handled in a future pass.
*/
tbin->avail[ndeferred] = ptr;
ndeferred++;
}
}
malloc_mutex_unlock(&bin->lock);
}
if (config_stats && merged_stats == false) {
/*
* The flush loop didn't happen to flush to this thread's
* arena, so the stats didn't get merged. Manually do so now.
*/
arena_bin_t *bin = &tcache->arena->bins[binind];
malloc_mutex_lock(&bin->lock);
bin->stats.nflushes++;
bin->stats.nrequests += tbin->tstats.nrequests;
tbin->tstats.nrequests = 0;
malloc_mutex_unlock(&bin->lock);
}
memmove(tbin->avail, &tbin->avail[tbin->ncached - rem],
rem * sizeof(void *));
tbin->ncached = rem;
if ((int)tbin->ncached < tbin->low_water)
tbin->low_water = tbin->ncached;
}
void
tcache_bin_flush_large(tcache_bin_t *tbin, size_t binind, unsigned rem,
tcache_t *tcache)
{
void *ptr;
unsigned i, nflush, ndeferred;
bool merged_stats = false;
assert(binind < nhbins);
assert(rem <= tbin->ncached);
for (nflush = tbin->ncached - rem; nflush > 0; nflush = ndeferred) {
/* Lock the arena associated with the first object. */
arena_chunk_t *chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(
tbin->avail[0]);
arena_t *arena = chunk->arena;
UNUSED bool idump;
if (config_prof)
idump = false;
malloc_mutex_lock(&arena->lock);
if ((config_prof || config_stats) && arena == tcache->arena) {
if (config_prof) {
idump = arena_prof_accum_locked(arena,
tcache->prof_accumbytes);
tcache->prof_accumbytes = 0;
}
if (config_stats) {
merged_stats = true;
arena->stats.nrequests_large +=
tbin->tstats.nrequests;
arena->stats.lstats[binind - NBINS].nrequests +=
tbin->tstats.nrequests;
tbin->tstats.nrequests = 0;
}
}
ndeferred = 0;
for (i = 0; i < nflush; i++) {
ptr = tbin->avail[i];
assert(ptr != NULL);
chunk = (arena_chunk_t *)CHUNK_ADDR2BASE(ptr);
if (chunk->arena == arena)
arena_dalloc_large_locked(arena, chunk, ptr);
else {
/*
* This object was allocated via a different
* arena than the one that is currently locked.
* Stash the object, so that it can be handled
* in a future pass.
*/
tbin->avail[ndeferred] = ptr;
ndeferred++;
}
}
malloc_mutex_unlock(&arena->lock);
if (config_prof && idump)
prof_idump();
}
if (config_stats && merged_stats == false) {
/*
* The flush loop didn't happen to flush to this thread's
* arena, so the stats didn't get merged. Manually do so now.
*/
arena_t *arena = tcache->arena;
malloc_mutex_lock(&arena->lock);
arena->stats.nrequests_large += tbin->tstats.nrequests;
arena->stats.lstats[binind - NBINS].nrequests +=
tbin->tstats.nrequests;
tbin->tstats.nrequests = 0;
malloc_mutex_unlock(&arena->lock);
}
memmove(tbin->avail, &tbin->avail[tbin->ncached - rem],
rem * sizeof(void *));
tbin->ncached = rem;
if ((int)tbin->ncached < tbin->low_water)
tbin->low_water = tbin->ncached;
}
void
tcache_arena_associate(tcache_t *tcache, arena_t *arena)
{
if (config_stats) {
/* Link into list of extant tcaches. */
malloc_mutex_lock(&arena->lock);
ql_elm_new(tcache, link);
ql_tail_insert(&arena->tcache_ql, tcache, link);
malloc_mutex_unlock(&arena->lock);
}
tcache->arena = arena;
}
void
tcache_arena_dissociate(tcache_t *tcache)
{
if (config_stats) {
/* Unlink from list of extant tcaches. */
malloc_mutex_lock(&tcache->arena->lock);
ql_remove(&tcache->arena->tcache_ql, tcache, link);
tcache_stats_merge(tcache, tcache->arena);
malloc_mutex_unlock(&tcache->arena->lock);
}
}
tcache_t *
tcache_get_hard(tcache_t *tcache, bool create)
{
if (tcache == NULL) {
if (create == false) {
/*
* Creating a tcache here would cause
* allocation as a side effect of free().
* Ordinarily that would be okay since
* tcache_create() failure is a soft failure
* that doesn't propagate. However, if TLS
* data are freed via free() as in glibc,
* subtle corruption could result from setting
* a TLS variable after its backing memory is
* freed.
*/
return (NULL);
}
if (tcache_enabled_get() == false) {
tcache_enabled_set(false); /* Memoize. */
return (NULL);
}
return (tcache_create(choose_arena(NULL)));
}
if (tcache == TCACHE_STATE_PURGATORY) {
/*
* Make a note that an allocator function was called
* after tcache_thread_cleanup() was called.
*/
tcache = TCACHE_STATE_REINCARNATED;
tcache_tsd_set(&tcache);
return (NULL);
}
if (tcache == TCACHE_STATE_REINCARNATED)
return (NULL);
not_reached();
return (NULL);
}
tcache_t *
tcache_create(arena_t *arena)
{
tcache_t *tcache;
size_t size, stack_offset;
unsigned i;
size = offsetof(tcache_t, tbins) + (sizeof(tcache_bin_t) * nhbins);
/* Naturally align the pointer stacks. */
size = PTR_CEILING(size);
stack_offset = size;
size += stack_nelms * sizeof(void *);
/*
* Round up to the nearest multiple of the cacheline size, in order to
* avoid the possibility of false cacheline sharing.
*
* That this works relies on the same logic as in ipalloc(), but we
* cannot directly call ipalloc() here due to tcache bootstrapping
* issues.
*/
size = (size + CACHELINE_MASK) & (-CACHELINE);
if (size <= SMALL_MAXCLASS)
tcache = (tcache_t *)arena_malloc_small(arena, size, true);
else if (size <= tcache_maxclass)
tcache = (tcache_t *)arena_malloc_large(arena, size, true);
else
tcache = (tcache_t *)icalloct(size, false, arena);
if (tcache == NULL)
return (NULL);
tcache_arena_associate(tcache, arena);
assert((TCACHE_NSLOTS_SMALL_MAX & 1U) == 0);
for (i = 0; i < nhbins; i++) {
tcache->tbins[i].lg_fill_div = 1;
tcache->tbins[i].avail = (void **)((uintptr_t)tcache +
(uintptr_t)stack_offset);
stack_offset += tcache_bin_info[i].ncached_max * sizeof(void *);
}
tcache_tsd_set(&tcache);
return (tcache);
}
void
tcache_destroy(tcache_t *tcache)
{
unsigned i;
size_t tcache_size;
tcache_arena_dissociate(tcache);
for (i = 0; i < NBINS; i++) {
tcache_bin_t *tbin = &tcache->tbins[i];
tcache_bin_flush_small(tbin, i, 0, tcache);
if (config_stats && tbin->tstats.nrequests != 0) {
arena_t *arena = tcache->arena;
arena_bin_t *bin = &arena->bins[i];
malloc_mutex_lock(&bin->lock);
bin->stats.nrequests += tbin->tstats.nrequests;
malloc_mutex_unlock(&bin->lock);
}
}
for (; i < nhbins; i++) {
tcache_bin_t *tbin = &tcache->tbins[i];
tcache_bin_flush_large(tbin, i, 0, tcache);
if (config_stats && tbin->tstats.nrequests != 0) {
arena_t *arena = tcache->arena;
malloc_mutex_lock(&arena->lock);
arena->stats.nrequests_large += tbin->tstats.nrequests;
arena->stats.lstats[i - NBINS].nrequests +=
tbin->tstats.nrequests;
malloc_mutex_unlock(&arena->lock);
}
}
if (config_prof && tcache->prof_accumbytes > 0 &&
arena_prof_accum(tcache->arena, tcache->prof_accumbytes))
prof_idump();
tcache_size = arena_salloc(tcache, false);
if (tcache_size <= SMALL_MAXCLASS) {
arena_chunk_t *chunk = CHUNK_ADDR2BASE(tcache);
arena_t *arena = chunk->arena;
size_t pageind = ((uintptr_t)tcache - (uintptr_t)chunk) >>
LG_PAGE;
arena_chunk_map_t *mapelm = arena_mapp_get(chunk, pageind);
arena_dalloc_bin(arena, chunk, tcache, pageind, mapelm);
} else if (tcache_size <= tcache_maxclass) {
arena_chunk_t *chunk = CHUNK_ADDR2BASE(tcache);
arena_t *arena = chunk->arena;
arena_dalloc_large(arena, chunk, tcache);
} else
idalloct(tcache, false);
}
void
tcache_thread_cleanup(void *arg)
{
tcache_t *tcache = *(tcache_t **)arg;
if (tcache == TCACHE_STATE_DISABLED) {
/* Do nothing. */
} else if (tcache == TCACHE_STATE_REINCARNATED) {
/*
* Another destructor called an allocator function after this
* destructor was called. Reset tcache to
* TCACHE_STATE_PURGATORY in order to receive another callback.
*/
tcache = TCACHE_STATE_PURGATORY;
tcache_tsd_set(&tcache);
} else if (tcache == TCACHE_STATE_PURGATORY) {
/*
* The previous time this destructor was called, we set the key
* to TCACHE_STATE_PURGATORY so that other destructors wouldn't
* cause re-creation of the tcache. This time, do nothing, so
* that the destructor will not be called again.
*/
} else if (tcache != NULL) {
assert(tcache != TCACHE_STATE_PURGATORY);
tcache_destroy(tcache);
tcache = TCACHE_STATE_PURGATORY;
tcache_tsd_set(&tcache);
}
}
/* Caller must own arena->lock. */
void
tcache_stats_merge(tcache_t *tcache, arena_t *arena)
{
unsigned i;
cassert(config_stats);
/* Merge and reset tcache stats. */
for (i = 0; i < NBINS; i++) {
arena_bin_t *bin = &arena->bins[i];
tcache_bin_t *tbin = &tcache->tbins[i];
malloc_mutex_lock(&bin->lock);
bin->stats.nrequests += tbin->tstats.nrequests;
malloc_mutex_unlock(&bin->lock);
tbin->tstats.nrequests = 0;
}
for (; i < nhbins; i++) {
malloc_large_stats_t *lstats = &arena->stats.lstats[i - NBINS];
tcache_bin_t *tbin = &tcache->tbins[i];
arena->stats.nrequests_large += tbin->tstats.nrequests;
lstats->nrequests += tbin->tstats.nrequests;
tbin->tstats.nrequests = 0;
}
}
bool
tcache_boot0(void)
{
unsigned i;
/*
* If necessary, clamp opt_lg_tcache_max, now that arena_maxclass is
* known.
*/
if (opt_lg_tcache_max < 0 || (1U << opt_lg_tcache_max) < SMALL_MAXCLASS)
tcache_maxclass = SMALL_MAXCLASS;
else if ((1U << opt_lg_tcache_max) > arena_maxclass)
tcache_maxclass = arena_maxclass;
else
tcache_maxclass = (1U << opt_lg_tcache_max);
nhbins = NBINS + (tcache_maxclass >> LG_PAGE);
/* Initialize tcache_bin_info. */
tcache_bin_info = (tcache_bin_info_t *)base_alloc(nhbins *
sizeof(tcache_bin_info_t));
if (tcache_bin_info == NULL)
return (true);
stack_nelms = 0;
for (i = 0; i < NBINS; i++) {
if ((arena_bin_info[i].nregs << 1) <= TCACHE_NSLOTS_SMALL_MAX) {
tcache_bin_info[i].ncached_max =
(arena_bin_info[i].nregs << 1);
} else {
tcache_bin_info[i].ncached_max =
TCACHE_NSLOTS_SMALL_MAX;
}
stack_nelms += tcache_bin_info[i].ncached_max;
}
for (; i < nhbins; i++) {
tcache_bin_info[i].ncached_max = TCACHE_NSLOTS_LARGE;
stack_nelms += tcache_bin_info[i].ncached_max;
}
return (false);
}
bool
tcache_boot1(void)
{
if (tcache_tsd_boot() || tcache_enabled_tsd_boot())
return (true);
return (false);
}