1 #define JEMALLOC_ARENA_C_
2 #include "jemalloc/internal/jemalloc_preamble.h"
3 #include "jemalloc/internal/jemalloc_internal_includes.h"
5 #include "jemalloc/internal/assert.h"
6 #include "jemalloc/internal/div.h"
7 #include "jemalloc/internal/extent_dss.h"
8 #include "jemalloc/internal/extent_mmap.h"
9 #include "jemalloc/internal/mutex.h"
10 #include "jemalloc/internal/rtree.h"
11 #include "jemalloc/internal/size_classes.h"
12 #include "jemalloc/internal/util.h"
14 /******************************************************************************/
18 * Define names for both unininitialized and initialized phases, so that
19 * options and mallctl processing are straightforward.
21 const char *percpu_arena_mode_names[] = {
28 percpu_arena_mode_t opt_percpu_arena = PERCPU_ARENA_DEFAULT;
30 ssize_t opt_dirty_decay_ms = DIRTY_DECAY_MS_DEFAULT;
31 ssize_t opt_muzzy_decay_ms = MUZZY_DECAY_MS_DEFAULT;
33 static atomic_zd_t dirty_decay_ms_default;
34 static atomic_zd_t muzzy_decay_ms_default;
36 const uint64_t h_steps[SMOOTHSTEP_NSTEPS] = {
37 #define STEP(step, h, x, y) \
43 static div_info_t arena_binind_div_info[NBINS];
45 /******************************************************************************/
47 * Function prototypes for static functions that are referenced prior to
51 static void arena_decay_to_limit(tsdn_t *tsdn, arena_t *arena,
52 arena_decay_t *decay, extents_t *extents, bool all, size_t npages_limit,
53 size_t npages_decay_max, bool is_background_thread);
54 static bool arena_decay_dirty(tsdn_t *tsdn, arena_t *arena,
55 bool is_background_thread, bool all);
56 static void arena_dalloc_bin_slab(tsdn_t *tsdn, arena_t *arena, extent_t *slab,
58 static void arena_bin_lower_slab(tsdn_t *tsdn, arena_t *arena, extent_t *slab,
61 /******************************************************************************/
64 arena_basic_stats_merge(UNUSED tsdn_t *tsdn, arena_t *arena, unsigned *nthreads,
65 const char **dss, ssize_t *dirty_decay_ms, ssize_t *muzzy_decay_ms,
66 size_t *nactive, size_t *ndirty, size_t *nmuzzy) {
67 *nthreads += arena_nthreads_get(arena, false);
68 *dss = dss_prec_names[arena_dss_prec_get(arena)];
69 *dirty_decay_ms = arena_dirty_decay_ms_get(arena);
70 *muzzy_decay_ms = arena_muzzy_decay_ms_get(arena);
71 *nactive += atomic_load_zu(&arena->nactive, ATOMIC_RELAXED);
72 *ndirty += extents_npages_get(&arena->extents_dirty);
73 *nmuzzy += extents_npages_get(&arena->extents_muzzy);
77 arena_stats_merge(tsdn_t *tsdn, arena_t *arena, unsigned *nthreads,
78 const char **dss, ssize_t *dirty_decay_ms, ssize_t *muzzy_decay_ms,
79 size_t *nactive, size_t *ndirty, size_t *nmuzzy, arena_stats_t *astats,
80 bin_stats_t *bstats, arena_stats_large_t *lstats) {
81 cassert(config_stats);
83 arena_basic_stats_merge(tsdn, arena, nthreads, dss, dirty_decay_ms,
84 muzzy_decay_ms, nactive, ndirty, nmuzzy);
86 size_t base_allocated, base_resident, base_mapped, metadata_thp;
87 base_stats_get(tsdn, arena->base, &base_allocated, &base_resident,
88 &base_mapped, &metadata_thp);
90 arena_stats_lock(tsdn, &arena->stats);
92 arena_stats_accum_zu(&astats->mapped, base_mapped
93 + arena_stats_read_zu(tsdn, &arena->stats, &arena->stats.mapped));
94 arena_stats_accum_zu(&astats->retained,
95 extents_npages_get(&arena->extents_retained) << LG_PAGE);
97 arena_stats_accum_u64(&astats->decay_dirty.npurge,
98 arena_stats_read_u64(tsdn, &arena->stats,
99 &arena->stats.decay_dirty.npurge));
100 arena_stats_accum_u64(&astats->decay_dirty.nmadvise,
101 arena_stats_read_u64(tsdn, &arena->stats,
102 &arena->stats.decay_dirty.nmadvise));
103 arena_stats_accum_u64(&astats->decay_dirty.purged,
104 arena_stats_read_u64(tsdn, &arena->stats,
105 &arena->stats.decay_dirty.purged));
107 arena_stats_accum_u64(&astats->decay_muzzy.npurge,
108 arena_stats_read_u64(tsdn, &arena->stats,
109 &arena->stats.decay_muzzy.npurge));
110 arena_stats_accum_u64(&astats->decay_muzzy.nmadvise,
111 arena_stats_read_u64(tsdn, &arena->stats,
112 &arena->stats.decay_muzzy.nmadvise));
113 arena_stats_accum_u64(&astats->decay_muzzy.purged,
114 arena_stats_read_u64(tsdn, &arena->stats,
115 &arena->stats.decay_muzzy.purged));
117 arena_stats_accum_zu(&astats->base, base_allocated);
118 arena_stats_accum_zu(&astats->internal, arena_internal_get(arena));
119 arena_stats_accum_zu(&astats->metadata_thp, metadata_thp);
120 arena_stats_accum_zu(&astats->resident, base_resident +
121 (((atomic_load_zu(&arena->nactive, ATOMIC_RELAXED) +
122 extents_npages_get(&arena->extents_dirty) +
123 extents_npages_get(&arena->extents_muzzy)) << LG_PAGE)));
125 for (szind_t i = 0; i < NSIZES - NBINS; i++) {
126 uint64_t nmalloc = arena_stats_read_u64(tsdn, &arena->stats,
127 &arena->stats.lstats[i].nmalloc);
128 arena_stats_accum_u64(&lstats[i].nmalloc, nmalloc);
129 arena_stats_accum_u64(&astats->nmalloc_large, nmalloc);
131 uint64_t ndalloc = arena_stats_read_u64(tsdn, &arena->stats,
132 &arena->stats.lstats[i].ndalloc);
133 arena_stats_accum_u64(&lstats[i].ndalloc, ndalloc);
134 arena_stats_accum_u64(&astats->ndalloc_large, ndalloc);
136 uint64_t nrequests = arena_stats_read_u64(tsdn, &arena->stats,
137 &arena->stats.lstats[i].nrequests);
138 arena_stats_accum_u64(&lstats[i].nrequests,
139 nmalloc + nrequests);
140 arena_stats_accum_u64(&astats->nrequests_large,
141 nmalloc + nrequests);
143 assert(nmalloc >= ndalloc);
144 assert(nmalloc - ndalloc <= SIZE_T_MAX);
145 size_t curlextents = (size_t)(nmalloc - ndalloc);
146 lstats[i].curlextents += curlextents;
147 arena_stats_accum_zu(&astats->allocated_large,
148 curlextents * sz_index2size(NBINS + i));
151 arena_stats_unlock(tsdn, &arena->stats);
153 /* tcache_bytes counts currently cached bytes. */
154 atomic_store_zu(&astats->tcache_bytes, 0, ATOMIC_RELAXED);
155 malloc_mutex_lock(tsdn, &arena->tcache_ql_mtx);
156 cache_bin_array_descriptor_t *descriptor;
157 ql_foreach(descriptor, &arena->cache_bin_array_descriptor_ql, link) {
159 for (; i < NBINS; i++) {
160 cache_bin_t *tbin = &descriptor->bins_small[i];
161 arena_stats_accum_zu(&astats->tcache_bytes,
162 tbin->ncached * sz_index2size(i));
164 for (; i < nhbins; i++) {
165 cache_bin_t *tbin = &descriptor->bins_large[i];
166 arena_stats_accum_zu(&astats->tcache_bytes,
167 tbin->ncached * sz_index2size(i));
170 malloc_mutex_prof_read(tsdn,
171 &astats->mutex_prof_data[arena_prof_mutex_tcache_list],
172 &arena->tcache_ql_mtx);
173 malloc_mutex_unlock(tsdn, &arena->tcache_ql_mtx);
175 #define READ_ARENA_MUTEX_PROF_DATA(mtx, ind) \
176 malloc_mutex_lock(tsdn, &arena->mtx); \
177 malloc_mutex_prof_read(tsdn, &astats->mutex_prof_data[ind], \
179 malloc_mutex_unlock(tsdn, &arena->mtx);
181 /* Gather per arena mutex profiling data. */
182 READ_ARENA_MUTEX_PROF_DATA(large_mtx, arena_prof_mutex_large);
183 READ_ARENA_MUTEX_PROF_DATA(extent_avail_mtx,
184 arena_prof_mutex_extent_avail)
185 READ_ARENA_MUTEX_PROF_DATA(extents_dirty.mtx,
186 arena_prof_mutex_extents_dirty)
187 READ_ARENA_MUTEX_PROF_DATA(extents_muzzy.mtx,
188 arena_prof_mutex_extents_muzzy)
189 READ_ARENA_MUTEX_PROF_DATA(extents_retained.mtx,
190 arena_prof_mutex_extents_retained)
191 READ_ARENA_MUTEX_PROF_DATA(decay_dirty.mtx,
192 arena_prof_mutex_decay_dirty)
193 READ_ARENA_MUTEX_PROF_DATA(decay_muzzy.mtx,
194 arena_prof_mutex_decay_muzzy)
195 READ_ARENA_MUTEX_PROF_DATA(base->mtx,
196 arena_prof_mutex_base)
197 #undef READ_ARENA_MUTEX_PROF_DATA
199 nstime_copy(&astats->uptime, &arena->create_time);
200 nstime_update(&astats->uptime);
201 nstime_subtract(&astats->uptime, &arena->create_time);
203 for (szind_t i = 0; i < NBINS; i++) {
204 bin_stats_merge(tsdn, &bstats[i], &arena->bins[i]);
209 arena_extents_dirty_dalloc(tsdn_t *tsdn, arena_t *arena,
210 extent_hooks_t **r_extent_hooks, extent_t *extent) {
211 witness_assert_depth_to_rank(tsdn_witness_tsdp_get(tsdn),
212 WITNESS_RANK_CORE, 0);
214 extents_dalloc(tsdn, arena, r_extent_hooks, &arena->extents_dirty,
216 if (arena_dirty_decay_ms_get(arena) == 0) {
217 arena_decay_dirty(tsdn, arena, false, true);
219 arena_background_thread_inactivity_check(tsdn, arena, false);
224 arena_slab_reg_alloc(extent_t *slab, const bin_info_t *bin_info) {
226 arena_slab_data_t *slab_data = extent_slab_data_get(slab);
229 assert(extent_nfree_get(slab) > 0);
230 assert(!bitmap_full(slab_data->bitmap, &bin_info->bitmap_info));
232 regind = bitmap_sfu(slab_data->bitmap, &bin_info->bitmap_info);
233 ret = (void *)((uintptr_t)extent_addr_get(slab) +
234 (uintptr_t)(bin_info->reg_size * regind));
235 extent_nfree_dec(slab);
243 arena_slab_regind(extent_t *slab, szind_t binind, const void *ptr) {
246 /* Freeing a pointer outside the slab can cause assertion failure. */
247 assert((uintptr_t)ptr >= (uintptr_t)extent_addr_get(slab));
248 assert((uintptr_t)ptr < (uintptr_t)extent_past_get(slab));
249 /* Freeing an interior pointer can cause assertion failure. */
250 assert(((uintptr_t)ptr - (uintptr_t)extent_addr_get(slab)) %
251 (uintptr_t)bin_infos[binind].reg_size == 0);
253 diff = (size_t)((uintptr_t)ptr - (uintptr_t)extent_addr_get(slab));
255 /* Avoid doing division with a variable divisor. */
256 regind = div_compute(&arena_binind_div_info[binind], diff);
258 assert(regind < bin_infos[binind].nregs);
264 arena_slab_reg_dalloc(extent_t *slab, arena_slab_data_t *slab_data, void *ptr) {
265 szind_t binind = extent_szind_get(slab);
266 const bin_info_t *bin_info = &bin_infos[binind];
267 size_t regind = arena_slab_regind(slab, binind, ptr);
269 assert(extent_nfree_get(slab) < bin_info->nregs);
270 /* Freeing an unallocated pointer can cause assertion failure. */
271 assert(bitmap_get(slab_data->bitmap, &bin_info->bitmap_info, regind));
273 bitmap_unset(slab_data->bitmap, &bin_info->bitmap_info, regind);
274 extent_nfree_inc(slab);
278 arena_nactive_add(arena_t *arena, size_t add_pages) {
279 atomic_fetch_add_zu(&arena->nactive, add_pages, ATOMIC_RELAXED);
283 arena_nactive_sub(arena_t *arena, size_t sub_pages) {
284 assert(atomic_load_zu(&arena->nactive, ATOMIC_RELAXED) >= sub_pages);
285 atomic_fetch_sub_zu(&arena->nactive, sub_pages, ATOMIC_RELAXED);
289 arena_large_malloc_stats_update(tsdn_t *tsdn, arena_t *arena, size_t usize) {
290 szind_t index, hindex;
292 cassert(config_stats);
294 if (usize < LARGE_MINCLASS) {
295 usize = LARGE_MINCLASS;
297 index = sz_size2index(usize);
298 hindex = (index >= NBINS) ? index - NBINS : 0;
300 arena_stats_add_u64(tsdn, &arena->stats,
301 &arena->stats.lstats[hindex].nmalloc, 1);
305 arena_large_dalloc_stats_update(tsdn_t *tsdn, arena_t *arena, size_t usize) {
306 szind_t index, hindex;
308 cassert(config_stats);
310 if (usize < LARGE_MINCLASS) {
311 usize = LARGE_MINCLASS;
313 index = sz_size2index(usize);
314 hindex = (index >= NBINS) ? index - NBINS : 0;
316 arena_stats_add_u64(tsdn, &arena->stats,
317 &arena->stats.lstats[hindex].ndalloc, 1);
321 arena_large_ralloc_stats_update(tsdn_t *tsdn, arena_t *arena, size_t oldusize,
323 arena_large_dalloc_stats_update(tsdn, arena, oldusize);
324 arena_large_malloc_stats_update(tsdn, arena, usize);
328 arena_extent_alloc_large(tsdn_t *tsdn, arena_t *arena, size_t usize,
329 size_t alignment, bool *zero) {
330 extent_hooks_t *extent_hooks = EXTENT_HOOKS_INITIALIZER;
332 witness_assert_depth_to_rank(tsdn_witness_tsdp_get(tsdn),
333 WITNESS_RANK_CORE, 0);
335 szind_t szind = sz_size2index(usize);
338 extent_t *extent = extents_alloc(tsdn, arena, &extent_hooks,
339 &arena->extents_dirty, NULL, usize, sz_large_pad, alignment, false,
340 szind, zero, &commit);
341 if (extent == NULL) {
342 extent = extents_alloc(tsdn, arena, &extent_hooks,
343 &arena->extents_muzzy, NULL, usize, sz_large_pad, alignment,
344 false, szind, zero, &commit);
346 size_t size = usize + sz_large_pad;
347 if (extent == NULL) {
348 extent = extent_alloc_wrapper(tsdn, arena, &extent_hooks, NULL,
349 usize, sz_large_pad, alignment, false, szind, zero,
353 * extent may be NULL on OOM, but in that case
354 * mapped_add isn't used below, so there's no need to
355 * conditionlly set it to 0 here.
359 } else if (config_stats) {
363 if (extent != NULL) {
365 arena_stats_lock(tsdn, &arena->stats);
366 arena_large_malloc_stats_update(tsdn, arena, usize);
367 if (mapped_add != 0) {
368 arena_stats_add_zu(tsdn, &arena->stats,
369 &arena->stats.mapped, mapped_add);
371 arena_stats_unlock(tsdn, &arena->stats);
373 arena_nactive_add(arena, size >> LG_PAGE);
380 arena_extent_dalloc_large_prep(tsdn_t *tsdn, arena_t *arena, extent_t *extent) {
382 arena_stats_lock(tsdn, &arena->stats);
383 arena_large_dalloc_stats_update(tsdn, arena,
384 extent_usize_get(extent));
385 arena_stats_unlock(tsdn, &arena->stats);
387 arena_nactive_sub(arena, extent_size_get(extent) >> LG_PAGE);
391 arena_extent_ralloc_large_shrink(tsdn_t *tsdn, arena_t *arena, extent_t *extent,
393 size_t usize = extent_usize_get(extent);
394 size_t udiff = oldusize - usize;
397 arena_stats_lock(tsdn, &arena->stats);
398 arena_large_ralloc_stats_update(tsdn, arena, oldusize, usize);
399 arena_stats_unlock(tsdn, &arena->stats);
401 arena_nactive_sub(arena, udiff >> LG_PAGE);
405 arena_extent_ralloc_large_expand(tsdn_t *tsdn, arena_t *arena, extent_t *extent,
407 size_t usize = extent_usize_get(extent);
408 size_t udiff = usize - oldusize;
411 arena_stats_lock(tsdn, &arena->stats);
412 arena_large_ralloc_stats_update(tsdn, arena, oldusize, usize);
413 arena_stats_unlock(tsdn, &arena->stats);
415 arena_nactive_add(arena, udiff >> LG_PAGE);
419 arena_decay_ms_read(arena_decay_t *decay) {
420 return atomic_load_zd(&decay->time_ms, ATOMIC_RELAXED);
424 arena_decay_ms_write(arena_decay_t *decay, ssize_t decay_ms) {
425 atomic_store_zd(&decay->time_ms, decay_ms, ATOMIC_RELAXED);
429 arena_decay_deadline_init(arena_decay_t *decay) {
431 * Generate a new deadline that is uniformly random within the next
432 * epoch after the current one.
434 nstime_copy(&decay->deadline, &decay->epoch);
435 nstime_add(&decay->deadline, &decay->interval);
436 if (arena_decay_ms_read(decay) > 0) {
439 nstime_init(&jitter, prng_range_u64(&decay->jitter_state,
440 nstime_ns(&decay->interval)));
441 nstime_add(&decay->deadline, &jitter);
446 arena_decay_deadline_reached(const arena_decay_t *decay, const nstime_t *time) {
447 return (nstime_compare(&decay->deadline, time) <= 0);
451 arena_decay_backlog_npages_limit(const arena_decay_t *decay) {
453 size_t npages_limit_backlog;
457 * For each element of decay_backlog, multiply by the corresponding
458 * fixed-point smoothstep decay factor. Sum the products, then divide
459 * to round down to the nearest whole number of pages.
462 for (i = 0; i < SMOOTHSTEP_NSTEPS; i++) {
463 sum += decay->backlog[i] * h_steps[i];
465 npages_limit_backlog = (size_t)(sum >> SMOOTHSTEP_BFP);
467 return npages_limit_backlog;
471 arena_decay_backlog_update_last(arena_decay_t *decay, size_t current_npages) {
472 size_t npages_delta = (current_npages > decay->nunpurged) ?
473 current_npages - decay->nunpurged : 0;
474 decay->backlog[SMOOTHSTEP_NSTEPS-1] = npages_delta;
477 if (current_npages > decay->ceil_npages) {
478 decay->ceil_npages = current_npages;
480 size_t npages_limit = arena_decay_backlog_npages_limit(decay);
481 assert(decay->ceil_npages >= npages_limit);
482 if (decay->ceil_npages > npages_limit) {
483 decay->ceil_npages = npages_limit;
489 arena_decay_backlog_update(arena_decay_t *decay, uint64_t nadvance_u64,
490 size_t current_npages) {
491 if (nadvance_u64 >= SMOOTHSTEP_NSTEPS) {
492 memset(decay->backlog, 0, (SMOOTHSTEP_NSTEPS-1) *
495 size_t nadvance_z = (size_t)nadvance_u64;
497 assert((uint64_t)nadvance_z == nadvance_u64);
499 memmove(decay->backlog, &decay->backlog[nadvance_z],
500 (SMOOTHSTEP_NSTEPS - nadvance_z) * sizeof(size_t));
501 if (nadvance_z > 1) {
502 memset(&decay->backlog[SMOOTHSTEP_NSTEPS -
503 nadvance_z], 0, (nadvance_z-1) * sizeof(size_t));
507 arena_decay_backlog_update_last(decay, current_npages);
511 arena_decay_try_purge(tsdn_t *tsdn, arena_t *arena, arena_decay_t *decay,
512 extents_t *extents, size_t current_npages, size_t npages_limit,
513 bool is_background_thread) {
514 if (current_npages > npages_limit) {
515 arena_decay_to_limit(tsdn, arena, decay, extents, false,
516 npages_limit, current_npages - npages_limit,
517 is_background_thread);
522 arena_decay_epoch_advance_helper(arena_decay_t *decay, const nstime_t *time,
523 size_t current_npages) {
524 assert(arena_decay_deadline_reached(decay, time));
527 nstime_copy(&delta, time);
528 nstime_subtract(&delta, &decay->epoch);
530 uint64_t nadvance_u64 = nstime_divide(&delta, &decay->interval);
531 assert(nadvance_u64 > 0);
533 /* Add nadvance_u64 decay intervals to epoch. */
534 nstime_copy(&delta, &decay->interval);
535 nstime_imultiply(&delta, nadvance_u64);
536 nstime_add(&decay->epoch, &delta);
538 /* Set a new deadline. */
539 arena_decay_deadline_init(decay);
541 /* Update the backlog. */
542 arena_decay_backlog_update(decay, nadvance_u64, current_npages);
546 arena_decay_epoch_advance(tsdn_t *tsdn, arena_t *arena, arena_decay_t *decay,
547 extents_t *extents, const nstime_t *time, bool is_background_thread) {
548 size_t current_npages = extents_npages_get(extents);
549 arena_decay_epoch_advance_helper(decay, time, current_npages);
551 size_t npages_limit = arena_decay_backlog_npages_limit(decay);
552 /* We may unlock decay->mtx when try_purge(). Finish logging first. */
553 decay->nunpurged = (npages_limit > current_npages) ? npages_limit :
556 if (!background_thread_enabled() || is_background_thread) {
557 arena_decay_try_purge(tsdn, arena, decay, extents,
558 current_npages, npages_limit, is_background_thread);
563 arena_decay_reinit(arena_decay_t *decay, ssize_t decay_ms) {
564 arena_decay_ms_write(decay, decay_ms);
566 nstime_init(&decay->interval, (uint64_t)decay_ms *
568 nstime_idivide(&decay->interval, SMOOTHSTEP_NSTEPS);
571 nstime_init(&decay->epoch, 0);
572 nstime_update(&decay->epoch);
573 decay->jitter_state = (uint64_t)(uintptr_t)decay;
574 arena_decay_deadline_init(decay);
575 decay->nunpurged = 0;
576 memset(decay->backlog, 0, SMOOTHSTEP_NSTEPS * sizeof(size_t));
580 arena_decay_init(arena_decay_t *decay, ssize_t decay_ms,
581 arena_stats_decay_t *stats) {
583 for (size_t i = 0; i < sizeof(arena_decay_t); i++) {
584 assert(((char *)decay)[i] == 0);
586 decay->ceil_npages = 0;
588 if (malloc_mutex_init(&decay->mtx, "decay", WITNESS_RANK_DECAY,
589 malloc_mutex_rank_exclusive)) {
592 decay->purging = false;
593 arena_decay_reinit(decay, decay_ms);
594 /* Memory is zeroed, so there is no need to clear stats. */
596 decay->stats = stats;
602 arena_decay_ms_valid(ssize_t decay_ms) {
606 if (decay_ms == -1 || (uint64_t)decay_ms <= NSTIME_SEC_MAX *
614 arena_maybe_decay(tsdn_t *tsdn, arena_t *arena, arena_decay_t *decay,
615 extents_t *extents, bool is_background_thread) {
616 malloc_mutex_assert_owner(tsdn, &decay->mtx);
618 /* Purge all or nothing if the option is disabled. */
619 ssize_t decay_ms = arena_decay_ms_read(decay);
622 arena_decay_to_limit(tsdn, arena, decay, extents, false,
623 0, extents_npages_get(extents),
624 is_background_thread);
630 nstime_init(&time, 0);
631 nstime_update(&time);
632 if (unlikely(!nstime_monotonic() && nstime_compare(&decay->epoch, &time)
635 * Time went backwards. Move the epoch back in time and
636 * generate a new deadline, with the expectation that time
637 * typically flows forward for long enough periods of time that
638 * epochs complete. Unfortunately, this strategy is susceptible
639 * to clock jitter triggering premature epoch advances, but
640 * clock jitter estimation and compensation isn't feasible here
641 * because calls into this code are event-driven.
643 nstime_copy(&decay->epoch, &time);
644 arena_decay_deadline_init(decay);
646 /* Verify that time does not go backwards. */
647 assert(nstime_compare(&decay->epoch, &time) <= 0);
651 * If the deadline has been reached, advance to the current epoch and
652 * purge to the new limit if necessary. Note that dirty pages created
653 * during the current epoch are not subject to purge until a future
654 * epoch, so as a result purging only happens during epoch advances, or
655 * being triggered by background threads (scheduled event).
657 bool advance_epoch = arena_decay_deadline_reached(decay, &time);
659 arena_decay_epoch_advance(tsdn, arena, decay, extents, &time,
660 is_background_thread);
661 } else if (is_background_thread) {
662 arena_decay_try_purge(tsdn, arena, decay, extents,
663 extents_npages_get(extents),
664 arena_decay_backlog_npages_limit(decay),
665 is_background_thread);
668 return advance_epoch;
672 arena_decay_ms_get(arena_decay_t *decay) {
673 return arena_decay_ms_read(decay);
677 arena_dirty_decay_ms_get(arena_t *arena) {
678 return arena_decay_ms_get(&arena->decay_dirty);
682 arena_muzzy_decay_ms_get(arena_t *arena) {
683 return arena_decay_ms_get(&arena->decay_muzzy);
687 arena_decay_ms_set(tsdn_t *tsdn, arena_t *arena, arena_decay_t *decay,
688 extents_t *extents, ssize_t decay_ms) {
689 if (!arena_decay_ms_valid(decay_ms)) {
693 malloc_mutex_lock(tsdn, &decay->mtx);
695 * Restart decay backlog from scratch, which may cause many dirty pages
696 * to be immediately purged. It would conceptually be possible to map
697 * the old backlog onto the new backlog, but there is no justification
698 * for such complexity since decay_ms changes are intended to be
699 * infrequent, either between the {-1, 0, >0} states, or a one-time
700 * arbitrary change during initial arena configuration.
702 arena_decay_reinit(decay, decay_ms);
703 arena_maybe_decay(tsdn, arena, decay, extents, false);
704 malloc_mutex_unlock(tsdn, &decay->mtx);
710 arena_dirty_decay_ms_set(tsdn_t *tsdn, arena_t *arena,
712 return arena_decay_ms_set(tsdn, arena, &arena->decay_dirty,
713 &arena->extents_dirty, decay_ms);
717 arena_muzzy_decay_ms_set(tsdn_t *tsdn, arena_t *arena,
719 return arena_decay_ms_set(tsdn, arena, &arena->decay_muzzy,
720 &arena->extents_muzzy, decay_ms);
724 arena_stash_decayed(tsdn_t *tsdn, arena_t *arena,
725 extent_hooks_t **r_extent_hooks, extents_t *extents, size_t npages_limit,
726 size_t npages_decay_max, extent_list_t *decay_extents) {
727 witness_assert_depth_to_rank(tsdn_witness_tsdp_get(tsdn),
728 WITNESS_RANK_CORE, 0);
730 /* Stash extents according to npages_limit. */
733 while (nstashed < npages_decay_max &&
734 (extent = extents_evict(tsdn, arena, r_extent_hooks, extents,
735 npages_limit)) != NULL) {
736 extent_list_append(decay_extents, extent);
737 nstashed += extent_size_get(extent) >> LG_PAGE;
743 arena_decay_stashed(tsdn_t *tsdn, arena_t *arena,
744 extent_hooks_t **r_extent_hooks, arena_decay_t *decay, extents_t *extents,
745 bool all, extent_list_t *decay_extents, bool is_background_thread) {
746 UNUSED size_t nmadvise, nunmapped;
755 ssize_t muzzy_decay_ms = arena_muzzy_decay_ms_get(arena);
756 for (extent_t *extent = extent_list_first(decay_extents); extent !=
757 NULL; extent = extent_list_first(decay_extents)) {
761 size_t npages = extent_size_get(extent) >> LG_PAGE;
763 extent_list_remove(decay_extents, extent);
764 switch (extents_state_get(extents)) {
765 case extent_state_active:
767 case extent_state_dirty:
768 if (!all && muzzy_decay_ms != 0 &&
769 !extent_purge_lazy_wrapper(tsdn, arena,
770 r_extent_hooks, extent, 0,
771 extent_size_get(extent))) {
772 extents_dalloc(tsdn, arena, r_extent_hooks,
773 &arena->extents_muzzy, extent);
774 arena_background_thread_inactivity_check(tsdn,
775 arena, is_background_thread);
779 case extent_state_muzzy:
780 extent_dalloc_wrapper(tsdn, arena, r_extent_hooks,
786 case extent_state_retained:
793 arena_stats_lock(tsdn, &arena->stats);
794 arena_stats_add_u64(tsdn, &arena->stats, &decay->stats->npurge,
796 arena_stats_add_u64(tsdn, &arena->stats,
797 &decay->stats->nmadvise, nmadvise);
798 arena_stats_add_u64(tsdn, &arena->stats, &decay->stats->purged,
800 arena_stats_sub_zu(tsdn, &arena->stats, &arena->stats.mapped,
801 nunmapped << LG_PAGE);
802 arena_stats_unlock(tsdn, &arena->stats);
809 * npages_limit: Decay at most npages_decay_max pages without violating the
810 * invariant: (extents_npages_get(extents) >= npages_limit). We need an upper
811 * bound on number of pages in order to prevent unbounded growth (namely in
812 * stashed), otherwise unbounded new pages could be added to extents during the
813 * current decay run, so that the purging thread never finishes.
816 arena_decay_to_limit(tsdn_t *tsdn, arena_t *arena, arena_decay_t *decay,
817 extents_t *extents, bool all, size_t npages_limit, size_t npages_decay_max,
818 bool is_background_thread) {
819 witness_assert_depth_to_rank(tsdn_witness_tsdp_get(tsdn),
820 WITNESS_RANK_CORE, 1);
821 malloc_mutex_assert_owner(tsdn, &decay->mtx);
823 if (decay->purging) {
826 decay->purging = true;
827 malloc_mutex_unlock(tsdn, &decay->mtx);
829 extent_hooks_t *extent_hooks = extent_hooks_get(arena);
831 extent_list_t decay_extents;
832 extent_list_init(&decay_extents);
834 size_t npurge = arena_stash_decayed(tsdn, arena, &extent_hooks, extents,
835 npages_limit, npages_decay_max, &decay_extents);
837 UNUSED size_t npurged = arena_decay_stashed(tsdn, arena,
838 &extent_hooks, decay, extents, all, &decay_extents,
839 is_background_thread);
840 assert(npurged == npurge);
843 malloc_mutex_lock(tsdn, &decay->mtx);
844 decay->purging = false;
848 arena_decay_impl(tsdn_t *tsdn, arena_t *arena, arena_decay_t *decay,
849 extents_t *extents, bool is_background_thread, bool all) {
851 malloc_mutex_lock(tsdn, &decay->mtx);
852 arena_decay_to_limit(tsdn, arena, decay, extents, all, 0,
853 extents_npages_get(extents), is_background_thread);
854 malloc_mutex_unlock(tsdn, &decay->mtx);
859 if (malloc_mutex_trylock(tsdn, &decay->mtx)) {
860 /* No need to wait if another thread is in progress. */
864 bool epoch_advanced = arena_maybe_decay(tsdn, arena, decay, extents,
865 is_background_thread);
866 UNUSED size_t npages_new;
867 if (epoch_advanced) {
868 /* Backlog is updated on epoch advance. */
869 npages_new = decay->backlog[SMOOTHSTEP_NSTEPS-1];
871 malloc_mutex_unlock(tsdn, &decay->mtx);
873 if (have_background_thread && background_thread_enabled() &&
874 epoch_advanced && !is_background_thread) {
875 background_thread_interval_check(tsdn, arena, decay,
883 arena_decay_dirty(tsdn_t *tsdn, arena_t *arena, bool is_background_thread,
885 return arena_decay_impl(tsdn, arena, &arena->decay_dirty,
886 &arena->extents_dirty, is_background_thread, all);
890 arena_decay_muzzy(tsdn_t *tsdn, arena_t *arena, bool is_background_thread,
892 return arena_decay_impl(tsdn, arena, &arena->decay_muzzy,
893 &arena->extents_muzzy, is_background_thread, all);
897 arena_decay(tsdn_t *tsdn, arena_t *arena, bool is_background_thread, bool all) {
898 if (arena_decay_dirty(tsdn, arena, is_background_thread, all)) {
901 arena_decay_muzzy(tsdn, arena, is_background_thread, all);
905 arena_slab_dalloc(tsdn_t *tsdn, arena_t *arena, extent_t *slab) {
906 arena_nactive_sub(arena, extent_size_get(slab) >> LG_PAGE);
908 extent_hooks_t *extent_hooks = EXTENT_HOOKS_INITIALIZER;
909 arena_extents_dirty_dalloc(tsdn, arena, &extent_hooks, slab);
913 arena_bin_slabs_nonfull_insert(bin_t *bin, extent_t *slab) {
914 assert(extent_nfree_get(slab) > 0);
915 extent_heap_insert(&bin->slabs_nonfull, slab);
919 arena_bin_slabs_nonfull_remove(bin_t *bin, extent_t *slab) {
920 extent_heap_remove(&bin->slabs_nonfull, slab);
924 arena_bin_slabs_nonfull_tryget(bin_t *bin) {
925 extent_t *slab = extent_heap_remove_first(&bin->slabs_nonfull);
930 bin->stats.reslabs++;
936 arena_bin_slabs_full_insert(arena_t *arena, bin_t *bin, extent_t *slab) {
937 assert(extent_nfree_get(slab) == 0);
939 * Tracking extents is required by arena_reset, which is not allowed
940 * for auto arenas. Bypass this step to avoid touching the extent
941 * linkage (often results in cache misses) for auto arenas.
943 if (arena_is_auto(arena)) {
946 extent_list_append(&bin->slabs_full, slab);
950 arena_bin_slabs_full_remove(arena_t *arena, bin_t *bin, extent_t *slab) {
951 if (arena_is_auto(arena)) {
954 extent_list_remove(&bin->slabs_full, slab);
958 arena_reset(tsd_t *tsd, arena_t *arena) {
960 * Locking in this function is unintuitive. The caller guarantees that
961 * no concurrent operations are happening in this arena, but there are
962 * still reasons that some locking is necessary:
964 * - Some of the functions in the transitive closure of calls assume
965 * appropriate locks are held, and in some cases these locks are
966 * temporarily dropped to avoid lock order reversal or deadlock due to
968 * - mallctl("epoch", ...) may concurrently refresh stats. While
969 * strictly speaking this is a "concurrent operation", disallowing
970 * stats refreshes would impose an inconvenient burden.
973 /* Large allocations. */
974 malloc_mutex_lock(tsd_tsdn(tsd), &arena->large_mtx);
976 for (extent_t *extent = extent_list_first(&arena->large); extent !=
977 NULL; extent = extent_list_first(&arena->large)) {
978 void *ptr = extent_base_get(extent);
981 malloc_mutex_unlock(tsd_tsdn(tsd), &arena->large_mtx);
982 alloc_ctx_t alloc_ctx;
983 rtree_ctx_t *rtree_ctx = tsd_rtree_ctx(tsd);
984 rtree_szind_slab_read(tsd_tsdn(tsd), &extents_rtree, rtree_ctx,
985 (uintptr_t)ptr, true, &alloc_ctx.szind, &alloc_ctx.slab);
986 assert(alloc_ctx.szind != NSIZES);
988 if (config_stats || (config_prof && opt_prof)) {
989 usize = sz_index2size(alloc_ctx.szind);
990 assert(usize == isalloc(tsd_tsdn(tsd), ptr));
992 /* Remove large allocation from prof sample set. */
993 if (config_prof && opt_prof) {
994 prof_free(tsd, ptr, usize, &alloc_ctx);
996 large_dalloc(tsd_tsdn(tsd), extent);
997 malloc_mutex_lock(tsd_tsdn(tsd), &arena->large_mtx);
999 malloc_mutex_unlock(tsd_tsdn(tsd), &arena->large_mtx);
1002 for (unsigned i = 0; i < NBINS; i++) {
1004 bin_t *bin = &arena->bins[i];
1005 malloc_mutex_lock(tsd_tsdn(tsd), &bin->lock);
1006 if (bin->slabcur != NULL) {
1007 slab = bin->slabcur;
1008 bin->slabcur = NULL;
1009 malloc_mutex_unlock(tsd_tsdn(tsd), &bin->lock);
1010 arena_slab_dalloc(tsd_tsdn(tsd), arena, slab);
1011 malloc_mutex_lock(tsd_tsdn(tsd), &bin->lock);
1013 while ((slab = extent_heap_remove_first(&bin->slabs_nonfull)) !=
1015 malloc_mutex_unlock(tsd_tsdn(tsd), &bin->lock);
1016 arena_slab_dalloc(tsd_tsdn(tsd), arena, slab);
1017 malloc_mutex_lock(tsd_tsdn(tsd), &bin->lock);
1019 for (slab = extent_list_first(&bin->slabs_full); slab != NULL;
1020 slab = extent_list_first(&bin->slabs_full)) {
1021 arena_bin_slabs_full_remove(arena, bin, slab);
1022 malloc_mutex_unlock(tsd_tsdn(tsd), &bin->lock);
1023 arena_slab_dalloc(tsd_tsdn(tsd), arena, slab);
1024 malloc_mutex_lock(tsd_tsdn(tsd), &bin->lock);
1027 bin->stats.curregs = 0;
1028 bin->stats.curslabs = 0;
1030 malloc_mutex_unlock(tsd_tsdn(tsd), &bin->lock);
1033 atomic_store_zu(&arena->nactive, 0, ATOMIC_RELAXED);
1037 arena_destroy_retained(tsdn_t *tsdn, arena_t *arena) {
1039 * Iterate over the retained extents and destroy them. This gives the
1040 * extent allocator underlying the extent hooks an opportunity to unmap
1041 * all retained memory without having to keep its own metadata
1042 * structures. In practice, virtual memory for dss-allocated extents is
1043 * leaked here, so best practice is to avoid dss for arenas to be
1044 * destroyed, or provide custom extent hooks that track retained
1045 * dss-based extents for later reuse.
1047 extent_hooks_t *extent_hooks = extent_hooks_get(arena);
1049 while ((extent = extents_evict(tsdn, arena, &extent_hooks,
1050 &arena->extents_retained, 0)) != NULL) {
1051 extent_destroy_wrapper(tsdn, arena, &extent_hooks, extent);
1056 arena_destroy(tsd_t *tsd, arena_t *arena) {
1057 assert(base_ind_get(arena->base) >= narenas_auto);
1058 assert(arena_nthreads_get(arena, false) == 0);
1059 assert(arena_nthreads_get(arena, true) == 0);
1062 * No allocations have occurred since arena_reset() was called.
1063 * Furthermore, the caller (arena_i_destroy_ctl()) purged all cached
1064 * extents, so only retained extents may remain.
1066 assert(extents_npages_get(&arena->extents_dirty) == 0);
1067 assert(extents_npages_get(&arena->extents_muzzy) == 0);
1069 /* Deallocate retained memory. */
1070 arena_destroy_retained(tsd_tsdn(tsd), arena);
1073 * Remove the arena pointer from the arenas array. We rely on the fact
1074 * that there is no way for the application to get a dirty read from the
1075 * arenas array unless there is an inherent race in the application
1076 * involving access of an arena being concurrently destroyed. The
1077 * application must synchronize knowledge of the arena's validity, so as
1078 * long as we use an atomic write to update the arenas array, the
1079 * application will get a clean read any time after it synchronizes
1080 * knowledge that the arena is no longer valid.
1082 arena_set(base_ind_get(arena->base), NULL);
1085 * Destroy the base allocator, which manages all metadata ever mapped by
1088 base_delete(tsd_tsdn(tsd), arena->base);
1092 arena_slab_alloc_hard(tsdn_t *tsdn, arena_t *arena,
1093 extent_hooks_t **r_extent_hooks, const bin_info_t *bin_info,
1098 witness_assert_depth_to_rank(tsdn_witness_tsdp_get(tsdn),
1099 WITNESS_RANK_CORE, 0);
1103 slab = extent_alloc_wrapper(tsdn, arena, r_extent_hooks, NULL,
1104 bin_info->slab_size, 0, PAGE, true, szind, &zero, &commit);
1106 if (config_stats && slab != NULL) {
1107 arena_stats_mapped_add(tsdn, &arena->stats,
1108 bin_info->slab_size);
1115 arena_slab_alloc(tsdn_t *tsdn, arena_t *arena, szind_t binind,
1116 const bin_info_t *bin_info) {
1117 witness_assert_depth_to_rank(tsdn_witness_tsdp_get(tsdn),
1118 WITNESS_RANK_CORE, 0);
1120 extent_hooks_t *extent_hooks = EXTENT_HOOKS_INITIALIZER;
1121 szind_t szind = sz_size2index(bin_info->reg_size);
1124 extent_t *slab = extents_alloc(tsdn, arena, &extent_hooks,
1125 &arena->extents_dirty, NULL, bin_info->slab_size, 0, PAGE, true,
1126 binind, &zero, &commit);
1128 slab = extents_alloc(tsdn, arena, &extent_hooks,
1129 &arena->extents_muzzy, NULL, bin_info->slab_size, 0, PAGE,
1130 true, binind, &zero, &commit);
1133 slab = arena_slab_alloc_hard(tsdn, arena, &extent_hooks,
1139 assert(extent_slab_get(slab));
1141 /* Initialize slab internals. */
1142 arena_slab_data_t *slab_data = extent_slab_data_get(slab);
1143 extent_nfree_set(slab, bin_info->nregs);
1144 bitmap_init(slab_data->bitmap, &bin_info->bitmap_info, false);
1146 arena_nactive_add(arena, extent_size_get(slab) >> LG_PAGE);
1152 arena_bin_nonfull_slab_get(tsdn_t *tsdn, arena_t *arena, bin_t *bin,
1155 const bin_info_t *bin_info;
1157 /* Look for a usable slab. */
1158 slab = arena_bin_slabs_nonfull_tryget(bin);
1162 /* No existing slabs have any space available. */
1164 bin_info = &bin_infos[binind];
1166 /* Allocate a new slab. */
1167 malloc_mutex_unlock(tsdn, &bin->lock);
1168 /******************************/
1169 slab = arena_slab_alloc(tsdn, arena, binind, bin_info);
1170 /********************************/
1171 malloc_mutex_lock(tsdn, &bin->lock);
1174 bin->stats.nslabs++;
1175 bin->stats.curslabs++;
1181 * arena_slab_alloc() failed, but another thread may have made
1182 * sufficient memory available while this one dropped bin->lock above,
1183 * so search one more time.
1185 slab = arena_bin_slabs_nonfull_tryget(bin);
1193 /* Re-fill bin->slabcur, then call arena_slab_reg_alloc(). */
1195 arena_bin_malloc_hard(tsdn_t *tsdn, arena_t *arena, bin_t *bin,
1197 const bin_info_t *bin_info;
1200 bin_info = &bin_infos[binind];
1201 if (!arena_is_auto(arena) && bin->slabcur != NULL) {
1202 arena_bin_slabs_full_insert(arena, bin, bin->slabcur);
1203 bin->slabcur = NULL;
1205 slab = arena_bin_nonfull_slab_get(tsdn, arena, bin, binind);
1206 if (bin->slabcur != NULL) {
1208 * Another thread updated slabcur while this one ran without the
1209 * bin lock in arena_bin_nonfull_slab_get().
1211 if (extent_nfree_get(bin->slabcur) > 0) {
1212 void *ret = arena_slab_reg_alloc(bin->slabcur,
1216 * arena_slab_alloc() may have allocated slab,
1217 * or it may have been pulled from
1218 * slabs_nonfull. Therefore it is unsafe to
1219 * make any assumptions about how slab has
1220 * previously been used, and
1221 * arena_bin_lower_slab() must be called, as if
1222 * a region were just deallocated from the slab.
1224 if (extent_nfree_get(slab) == bin_info->nregs) {
1225 arena_dalloc_bin_slab(tsdn, arena, slab,
1228 arena_bin_lower_slab(tsdn, arena, slab,
1235 arena_bin_slabs_full_insert(arena, bin, bin->slabcur);
1236 bin->slabcur = NULL;
1242 bin->slabcur = slab;
1244 assert(extent_nfree_get(bin->slabcur) > 0);
1246 return arena_slab_reg_alloc(slab, bin_info);
1250 arena_tcache_fill_small(tsdn_t *tsdn, arena_t *arena, tcache_t *tcache,
1251 cache_bin_t *tbin, szind_t binind, uint64_t prof_accumbytes) {
1255 assert(tbin->ncached == 0);
1257 if (config_prof && arena_prof_accum(tsdn, arena, prof_accumbytes)) {
1260 bin = &arena->bins[binind];
1261 malloc_mutex_lock(tsdn, &bin->lock);
1262 for (i = 0, nfill = (tcache_bin_info[binind].ncached_max >>
1263 tcache->lg_fill_div[binind]); i < nfill; i++) {
1266 if ((slab = bin->slabcur) != NULL && extent_nfree_get(slab) >
1268 ptr = arena_slab_reg_alloc(slab, &bin_infos[binind]);
1270 ptr = arena_bin_malloc_hard(tsdn, arena, bin, binind);
1274 * OOM. tbin->avail isn't yet filled down to its first
1275 * element, so the successful allocations (if any) must
1276 * be moved just before tbin->avail before bailing out.
1279 memmove(tbin->avail - i, tbin->avail - nfill,
1280 i * sizeof(void *));
1284 if (config_fill && unlikely(opt_junk_alloc)) {
1285 arena_alloc_junk_small(ptr, &bin_infos[binind], true);
1287 /* Insert such that low regions get used first. */
1288 *(tbin->avail - nfill + i) = ptr;
1291 bin->stats.nmalloc += i;
1292 bin->stats.nrequests += tbin->tstats.nrequests;
1293 bin->stats.curregs += i;
1294 bin->stats.nfills++;
1295 tbin->tstats.nrequests = 0;
1297 malloc_mutex_unlock(tsdn, &bin->lock);
1299 arena_decay_tick(tsdn, arena);
1303 arena_alloc_junk_small(void *ptr, const bin_info_t *bin_info, bool zero) {
1305 memset(ptr, JEMALLOC_ALLOC_JUNK, bin_info->reg_size);
1310 arena_dalloc_junk_small_impl(void *ptr, const bin_info_t *bin_info) {
1311 memset(ptr, JEMALLOC_FREE_JUNK, bin_info->reg_size);
1313 arena_dalloc_junk_small_t *JET_MUTABLE arena_dalloc_junk_small =
1314 arena_dalloc_junk_small_impl;
1317 arena_malloc_small(tsdn_t *tsdn, arena_t *arena, szind_t binind, bool zero) {
1323 assert(binind < NBINS);
1324 bin = &arena->bins[binind];
1325 usize = sz_index2size(binind);
1327 malloc_mutex_lock(tsdn, &bin->lock);
1328 if ((slab = bin->slabcur) != NULL && extent_nfree_get(slab) > 0) {
1329 ret = arena_slab_reg_alloc(slab, &bin_infos[binind]);
1331 ret = arena_bin_malloc_hard(tsdn, arena, bin, binind);
1335 malloc_mutex_unlock(tsdn, &bin->lock);
1340 bin->stats.nmalloc++;
1341 bin->stats.nrequests++;
1342 bin->stats.curregs++;
1344 malloc_mutex_unlock(tsdn, &bin->lock);
1345 if (config_prof && arena_prof_accum(tsdn, arena, usize)) {
1351 if (unlikely(opt_junk_alloc)) {
1352 arena_alloc_junk_small(ret,
1353 &bin_infos[binind], false);
1354 } else if (unlikely(opt_zero)) {
1355 memset(ret, 0, usize);
1359 if (config_fill && unlikely(opt_junk_alloc)) {
1360 arena_alloc_junk_small(ret, &bin_infos[binind],
1363 memset(ret, 0, usize);
1366 arena_decay_tick(tsdn, arena);
1371 arena_malloc_hard(tsdn_t *tsdn, arena_t *arena, size_t size, szind_t ind,
1373 assert(!tsdn_null(tsdn) || arena != NULL);
1375 if (likely(!tsdn_null(tsdn))) {
1376 arena = arena_choose(tsdn_tsd(tsdn), arena);
1378 if (unlikely(arena == NULL)) {
1382 if (likely(size <= SMALL_MAXCLASS)) {
1383 return arena_malloc_small(tsdn, arena, ind, zero);
1385 return large_malloc(tsdn, arena, sz_index2size(ind), zero);
1389 arena_palloc(tsdn_t *tsdn, arena_t *arena, size_t usize, size_t alignment,
1390 bool zero, tcache_t *tcache) {
1393 if (usize <= SMALL_MAXCLASS && (alignment < PAGE || (alignment == PAGE
1394 && (usize & PAGE_MASK) == 0))) {
1395 /* Small; alignment doesn't require special slab placement. */
1396 ret = arena_malloc(tsdn, arena, usize, sz_size2index(usize),
1397 zero, tcache, true);
1399 if (likely(alignment <= CACHELINE)) {
1400 ret = large_malloc(tsdn, arena, usize, zero);
1402 ret = large_palloc(tsdn, arena, usize, alignment, zero);
1409 arena_prof_promote(tsdn_t *tsdn, const void *ptr, size_t usize) {
1410 cassert(config_prof);
1411 assert(ptr != NULL);
1412 assert(isalloc(tsdn, ptr) == LARGE_MINCLASS);
1413 assert(usize <= SMALL_MAXCLASS);
1415 rtree_ctx_t rtree_ctx_fallback;
1416 rtree_ctx_t *rtree_ctx = tsdn_rtree_ctx(tsdn, &rtree_ctx_fallback);
1418 extent_t *extent = rtree_extent_read(tsdn, &extents_rtree, rtree_ctx,
1419 (uintptr_t)ptr, true);
1420 arena_t *arena = extent_arena_get(extent);
1422 szind_t szind = sz_size2index(usize);
1423 extent_szind_set(extent, szind);
1424 rtree_szind_slab_update(tsdn, &extents_rtree, rtree_ctx, (uintptr_t)ptr,
1427 prof_accum_cancel(tsdn, &arena->prof_accum, usize);
1429 assert(isalloc(tsdn, ptr) == usize);
1433 arena_prof_demote(tsdn_t *tsdn, extent_t *extent, const void *ptr) {
1434 cassert(config_prof);
1435 assert(ptr != NULL);
1437 extent_szind_set(extent, NBINS);
1438 rtree_ctx_t rtree_ctx_fallback;
1439 rtree_ctx_t *rtree_ctx = tsdn_rtree_ctx(tsdn, &rtree_ctx_fallback);
1440 rtree_szind_slab_update(tsdn, &extents_rtree, rtree_ctx, (uintptr_t)ptr,
1443 assert(isalloc(tsdn, ptr) == LARGE_MINCLASS);
1445 return LARGE_MINCLASS;
1449 arena_dalloc_promoted(tsdn_t *tsdn, void *ptr, tcache_t *tcache,
1451 cassert(config_prof);
1454 extent_t *extent = iealloc(tsdn, ptr);
1455 size_t usize = arena_prof_demote(tsdn, extent, ptr);
1456 if (usize <= tcache_maxclass) {
1457 tcache_dalloc_large(tsdn_tsd(tsdn), tcache, ptr,
1458 sz_size2index(usize), slow_path);
1460 large_dalloc(tsdn, extent);
1465 arena_dissociate_bin_slab(arena_t *arena, extent_t *slab, bin_t *bin) {
1466 /* Dissociate slab from bin. */
1467 if (slab == bin->slabcur) {
1468 bin->slabcur = NULL;
1470 szind_t binind = extent_szind_get(slab);
1471 const bin_info_t *bin_info = &bin_infos[binind];
1474 * The following block's conditional is necessary because if the
1475 * slab only contains one region, then it never gets inserted
1476 * into the non-full slabs heap.
1478 if (bin_info->nregs == 1) {
1479 arena_bin_slabs_full_remove(arena, bin, slab);
1481 arena_bin_slabs_nonfull_remove(bin, slab);
1487 arena_dalloc_bin_slab(tsdn_t *tsdn, arena_t *arena, extent_t *slab,
1489 assert(slab != bin->slabcur);
1491 malloc_mutex_unlock(tsdn, &bin->lock);
1492 /******************************/
1493 arena_slab_dalloc(tsdn, arena, slab);
1494 /****************************/
1495 malloc_mutex_lock(tsdn, &bin->lock);
1497 bin->stats.curslabs--;
1502 arena_bin_lower_slab(UNUSED tsdn_t *tsdn, arena_t *arena, extent_t *slab,
1504 assert(extent_nfree_get(slab) > 0);
1507 * Make sure that if bin->slabcur is non-NULL, it refers to the
1508 * oldest/lowest non-full slab. It is okay to NULL slabcur out rather
1509 * than proactively keeping it pointing at the oldest/lowest non-full
1512 if (bin->slabcur != NULL && extent_snad_comp(bin->slabcur, slab) > 0) {
1513 /* Switch slabcur. */
1514 if (extent_nfree_get(bin->slabcur) > 0) {
1515 arena_bin_slabs_nonfull_insert(bin, bin->slabcur);
1517 arena_bin_slabs_full_insert(arena, bin, bin->slabcur);
1519 bin->slabcur = slab;
1521 bin->stats.reslabs++;
1524 arena_bin_slabs_nonfull_insert(bin, slab);
1529 arena_dalloc_bin_locked_impl(tsdn_t *tsdn, arena_t *arena, extent_t *slab,
1530 void *ptr, bool junked) {
1531 arena_slab_data_t *slab_data = extent_slab_data_get(slab);
1532 szind_t binind = extent_szind_get(slab);
1533 bin_t *bin = &arena->bins[binind];
1534 const bin_info_t *bin_info = &bin_infos[binind];
1536 if (!junked && config_fill && unlikely(opt_junk_free)) {
1537 arena_dalloc_junk_small(ptr, bin_info);
1540 arena_slab_reg_dalloc(slab, slab_data, ptr);
1541 unsigned nfree = extent_nfree_get(slab);
1542 if (nfree == bin_info->nregs) {
1543 arena_dissociate_bin_slab(arena, slab, bin);
1544 arena_dalloc_bin_slab(tsdn, arena, slab, bin);
1545 } else if (nfree == 1 && slab != bin->slabcur) {
1546 arena_bin_slabs_full_remove(arena, bin, slab);
1547 arena_bin_lower_slab(tsdn, arena, slab, bin);
1551 bin->stats.ndalloc++;
1552 bin->stats.curregs--;
1557 arena_dalloc_bin_junked_locked(tsdn_t *tsdn, arena_t *arena, extent_t *extent,
1559 arena_dalloc_bin_locked_impl(tsdn, arena, extent, ptr, true);
1563 arena_dalloc_bin(tsdn_t *tsdn, arena_t *arena, extent_t *extent, void *ptr) {
1564 szind_t binind = extent_szind_get(extent);
1565 bin_t *bin = &arena->bins[binind];
1567 malloc_mutex_lock(tsdn, &bin->lock);
1568 arena_dalloc_bin_locked_impl(tsdn, arena, extent, ptr, false);
1569 malloc_mutex_unlock(tsdn, &bin->lock);
1573 arena_dalloc_small(tsdn_t *tsdn, void *ptr) {
1574 extent_t *extent = iealloc(tsdn, ptr);
1575 arena_t *arena = extent_arena_get(extent);
1577 arena_dalloc_bin(tsdn, arena, extent, ptr);
1578 arena_decay_tick(tsdn, arena);
1582 arena_ralloc_no_move(tsdn_t *tsdn, void *ptr, size_t oldsize, size_t size,
1583 size_t extra, bool zero) {
1584 /* Calls with non-zero extra had to clamp extra. */
1585 assert(extra == 0 || size + extra <= LARGE_MAXCLASS);
1587 if (unlikely(size > LARGE_MAXCLASS)) {
1591 extent_t *extent = iealloc(tsdn, ptr);
1592 size_t usize_min = sz_s2u(size);
1593 size_t usize_max = sz_s2u(size + extra);
1594 if (likely(oldsize <= SMALL_MAXCLASS && usize_min <= SMALL_MAXCLASS)) {
1596 * Avoid moving the allocation if the size class can be left the
1599 assert(bin_infos[sz_size2index(oldsize)].reg_size ==
1601 if ((usize_max > SMALL_MAXCLASS || sz_size2index(usize_max) !=
1602 sz_size2index(oldsize)) && (size > oldsize || usize_max <
1607 arena_decay_tick(tsdn, extent_arena_get(extent));
1609 } else if (oldsize >= LARGE_MINCLASS && usize_max >= LARGE_MINCLASS) {
1610 return large_ralloc_no_move(tsdn, extent, usize_min, usize_max,
1618 arena_ralloc_move_helper(tsdn_t *tsdn, arena_t *arena, size_t usize,
1619 size_t alignment, bool zero, tcache_t *tcache) {
1620 if (alignment == 0) {
1621 return arena_malloc(tsdn, arena, usize, sz_size2index(usize),
1622 zero, tcache, true);
1624 usize = sz_sa2u(usize, alignment);
1625 if (unlikely(usize == 0 || usize > LARGE_MAXCLASS)) {
1628 return ipalloct(tsdn, usize, alignment, zero, tcache, arena);
1632 arena_ralloc(tsdn_t *tsdn, arena_t *arena, void *ptr, size_t oldsize,
1633 size_t size, size_t alignment, bool zero, tcache_t *tcache) {
1634 size_t usize = sz_s2u(size);
1635 if (unlikely(usize == 0 || size > LARGE_MAXCLASS)) {
1639 if (likely(usize <= SMALL_MAXCLASS)) {
1640 /* Try to avoid moving the allocation. */
1641 if (!arena_ralloc_no_move(tsdn, ptr, oldsize, usize, 0, zero)) {
1646 if (oldsize >= LARGE_MINCLASS && usize >= LARGE_MINCLASS) {
1647 return large_ralloc(tsdn, arena, iealloc(tsdn, ptr), usize,
1648 alignment, zero, tcache);
1652 * size and oldsize are different enough that we need to move the
1653 * object. In that case, fall back to allocating new space and copying.
1655 void *ret = arena_ralloc_move_helper(tsdn, arena, usize, alignment,
1662 * Junk/zero-filling were already done by
1663 * ipalloc()/arena_malloc().
1666 size_t copysize = (usize < oldsize) ? usize : oldsize;
1667 memcpy(ret, ptr, copysize);
1668 isdalloct(tsdn, ptr, oldsize, tcache, NULL, true);
1673 arena_dss_prec_get(arena_t *arena) {
1674 return (dss_prec_t)atomic_load_u(&arena->dss_prec, ATOMIC_ACQUIRE);
1678 arena_dss_prec_set(arena_t *arena, dss_prec_t dss_prec) {
1680 return (dss_prec != dss_prec_disabled);
1682 atomic_store_u(&arena->dss_prec, (unsigned)dss_prec, ATOMIC_RELEASE);
1687 arena_dirty_decay_ms_default_get(void) {
1688 return atomic_load_zd(&dirty_decay_ms_default, ATOMIC_RELAXED);
1692 arena_dirty_decay_ms_default_set(ssize_t decay_ms) {
1693 if (!arena_decay_ms_valid(decay_ms)) {
1696 atomic_store_zd(&dirty_decay_ms_default, decay_ms, ATOMIC_RELAXED);
1701 arena_muzzy_decay_ms_default_get(void) {
1702 return atomic_load_zd(&muzzy_decay_ms_default, ATOMIC_RELAXED);
1706 arena_muzzy_decay_ms_default_set(ssize_t decay_ms) {
1707 if (!arena_decay_ms_valid(decay_ms)) {
1710 atomic_store_zd(&muzzy_decay_ms_default, decay_ms, ATOMIC_RELAXED);
1715 arena_retain_grow_limit_get_set(tsd_t *tsd, arena_t *arena, size_t *old_limit,
1716 size_t *new_limit) {
1719 pszind_t new_ind JEMALLOC_CC_SILENCE_INIT(0);
1720 if (new_limit != NULL) {
1721 size_t limit = *new_limit;
1722 /* Grow no more than the new limit. */
1723 if ((new_ind = sz_psz2ind(limit + 1) - 1) >
1724 EXTENT_GROW_MAX_PIND) {
1729 malloc_mutex_lock(tsd_tsdn(tsd), &arena->extent_grow_mtx);
1730 if (old_limit != NULL) {
1731 *old_limit = sz_pind2sz(arena->retain_grow_limit);
1733 if (new_limit != NULL) {
1734 arena->retain_grow_limit = new_ind;
1736 malloc_mutex_unlock(tsd_tsdn(tsd), &arena->extent_grow_mtx);
1742 arena_nthreads_get(arena_t *arena, bool internal) {
1743 return atomic_load_u(&arena->nthreads[internal], ATOMIC_RELAXED);
1747 arena_nthreads_inc(arena_t *arena, bool internal) {
1748 atomic_fetch_add_u(&arena->nthreads[internal], 1, ATOMIC_RELAXED);
1752 arena_nthreads_dec(arena_t *arena, bool internal) {
1753 atomic_fetch_sub_u(&arena->nthreads[internal], 1, ATOMIC_RELAXED);
1757 arena_extent_sn_next(arena_t *arena) {
1758 return atomic_fetch_add_zu(&arena->extent_sn_next, 1, ATOMIC_RELAXED);
1762 arena_new(tsdn_t *tsdn, unsigned ind, extent_hooks_t *extent_hooks) {
1770 base = base_new(tsdn, ind, extent_hooks);
1776 arena = (arena_t *)base_alloc(tsdn, base, sizeof(arena_t), CACHELINE);
1777 if (arena == NULL) {
1781 atomic_store_u(&arena->nthreads[0], 0, ATOMIC_RELAXED);
1782 atomic_store_u(&arena->nthreads[1], 0, ATOMIC_RELAXED);
1783 arena->last_thd = NULL;
1786 if (arena_stats_init(tsdn, &arena->stats)) {
1790 ql_new(&arena->tcache_ql);
1791 ql_new(&arena->cache_bin_array_descriptor_ql);
1792 if (malloc_mutex_init(&arena->tcache_ql_mtx, "tcache_ql",
1793 WITNESS_RANK_TCACHE_QL, malloc_mutex_rank_exclusive)) {
1799 if (prof_accum_init(tsdn, &arena->prof_accum)) {
1804 if (config_cache_oblivious) {
1806 * A nondeterministic seed based on the address of arena reduces
1807 * the likelihood of lockstep non-uniform cache index
1808 * utilization among identical concurrent processes, but at the
1809 * cost of test repeatability. For debug builds, instead use a
1810 * deterministic seed.
1812 atomic_store_zu(&arena->offset_state, config_debug ? ind :
1813 (size_t)(uintptr_t)arena, ATOMIC_RELAXED);
1816 atomic_store_zu(&arena->extent_sn_next, 0, ATOMIC_RELAXED);
1818 atomic_store_u(&arena->dss_prec, (unsigned)extent_dss_prec_get(),
1821 atomic_store_zu(&arena->nactive, 0, ATOMIC_RELAXED);
1823 extent_list_init(&arena->large);
1824 if (malloc_mutex_init(&arena->large_mtx, "arena_large",
1825 WITNESS_RANK_ARENA_LARGE, malloc_mutex_rank_exclusive)) {
1830 * Delay coalescing for dirty extents despite the disruptive effect on
1831 * memory layout for best-fit extent allocation, since cached extents
1832 * are likely to be reused soon after deallocation, and the cost of
1833 * merging/splitting extents is non-trivial.
1835 if (extents_init(tsdn, &arena->extents_dirty, extent_state_dirty,
1840 * Coalesce muzzy extents immediately, because operations on them are in
1841 * the critical path much less often than for dirty extents.
1843 if (extents_init(tsdn, &arena->extents_muzzy, extent_state_muzzy,
1848 * Coalesce retained extents immediately, in part because they will
1849 * never be evicted (and therefore there's no opportunity for delayed
1850 * coalescing), but also because operations on retained extents are not
1851 * in the critical path.
1853 if (extents_init(tsdn, &arena->extents_retained, extent_state_retained,
1858 if (arena_decay_init(&arena->decay_dirty,
1859 arena_dirty_decay_ms_default_get(), &arena->stats.decay_dirty)) {
1862 if (arena_decay_init(&arena->decay_muzzy,
1863 arena_muzzy_decay_ms_default_get(), &arena->stats.decay_muzzy)) {
1867 arena->extent_grow_next = sz_psz2ind(HUGEPAGE);
1868 arena->retain_grow_limit = EXTENT_GROW_MAX_PIND;
1869 if (malloc_mutex_init(&arena->extent_grow_mtx, "extent_grow",
1870 WITNESS_RANK_EXTENT_GROW, malloc_mutex_rank_exclusive)) {
1874 extent_avail_new(&arena->extent_avail);
1875 if (malloc_mutex_init(&arena->extent_avail_mtx, "extent_avail",
1876 WITNESS_RANK_EXTENT_AVAIL, malloc_mutex_rank_exclusive)) {
1880 /* Initialize bins. */
1881 for (i = 0; i < NBINS; i++) {
1882 bool err = bin_init(&arena->bins[i]);
1889 /* Set arena before creating background threads. */
1890 arena_set(ind, arena);
1892 nstime_init(&arena->create_time, 0);
1893 nstime_update(&arena->create_time);
1895 /* We don't support reentrancy for arena 0 bootstrapping. */
1898 * If we're here, then arena 0 already exists, so bootstrapping
1899 * is done enough that we should have tsd.
1901 assert(!tsdn_null(tsdn));
1902 pre_reentrancy(tsdn_tsd(tsdn), arena);
1903 if (hooks_arena_new_hook) {
1904 hooks_arena_new_hook();
1906 post_reentrancy(tsdn_tsd(tsdn));
1912 base_delete(tsdn, base);
1919 arena_dirty_decay_ms_default_set(opt_dirty_decay_ms);
1920 arena_muzzy_decay_ms_default_set(opt_muzzy_decay_ms);
1921 #define REGIND_bin_yes(index, reg_size) \
1922 div_init(&arena_binind_div_info[(index)], (reg_size));
1923 #define REGIND_bin_no(index, reg_size)
1924 #define SC(index, lg_grp, lg_delta, ndelta, psz, bin, pgs, \
1926 REGIND_bin_##bin(index, (1U<<lg_grp) + (ndelta << lg_delta))
1928 #undef REGIND_bin_yes
1929 #undef REGIND_bin_no
1934 arena_prefork0(tsdn_t *tsdn, arena_t *arena) {
1935 malloc_mutex_prefork(tsdn, &arena->decay_dirty.mtx);
1936 malloc_mutex_prefork(tsdn, &arena->decay_muzzy.mtx);
1940 arena_prefork1(tsdn_t *tsdn, arena_t *arena) {
1942 malloc_mutex_prefork(tsdn, &arena->tcache_ql_mtx);
1947 arena_prefork2(tsdn_t *tsdn, arena_t *arena) {
1948 malloc_mutex_prefork(tsdn, &arena->extent_grow_mtx);
1952 arena_prefork3(tsdn_t *tsdn, arena_t *arena) {
1953 extents_prefork(tsdn, &arena->extents_dirty);
1954 extents_prefork(tsdn, &arena->extents_muzzy);
1955 extents_prefork(tsdn, &arena->extents_retained);
1959 arena_prefork4(tsdn_t *tsdn, arena_t *arena) {
1960 malloc_mutex_prefork(tsdn, &arena->extent_avail_mtx);
1964 arena_prefork5(tsdn_t *tsdn, arena_t *arena) {
1965 base_prefork(tsdn, arena->base);
1969 arena_prefork6(tsdn_t *tsdn, arena_t *arena) {
1970 malloc_mutex_prefork(tsdn, &arena->large_mtx);
1974 arena_prefork7(tsdn_t *tsdn, arena_t *arena) {
1975 for (unsigned i = 0; i < NBINS; i++) {
1976 bin_prefork(tsdn, &arena->bins[i]);
1981 arena_postfork_parent(tsdn_t *tsdn, arena_t *arena) {
1984 for (i = 0; i < NBINS; i++) {
1985 bin_postfork_parent(tsdn, &arena->bins[i]);
1987 malloc_mutex_postfork_parent(tsdn, &arena->large_mtx);
1988 base_postfork_parent(tsdn, arena->base);
1989 malloc_mutex_postfork_parent(tsdn, &arena->extent_avail_mtx);
1990 extents_postfork_parent(tsdn, &arena->extents_dirty);
1991 extents_postfork_parent(tsdn, &arena->extents_muzzy);
1992 extents_postfork_parent(tsdn, &arena->extents_retained);
1993 malloc_mutex_postfork_parent(tsdn, &arena->extent_grow_mtx);
1994 malloc_mutex_postfork_parent(tsdn, &arena->decay_dirty.mtx);
1995 malloc_mutex_postfork_parent(tsdn, &arena->decay_muzzy.mtx);
1997 malloc_mutex_postfork_parent(tsdn, &arena->tcache_ql_mtx);
2002 arena_postfork_child(tsdn_t *tsdn, arena_t *arena) {
2005 atomic_store_u(&arena->nthreads[0], 0, ATOMIC_RELAXED);
2006 atomic_store_u(&arena->nthreads[1], 0, ATOMIC_RELAXED);
2007 if (tsd_arena_get(tsdn_tsd(tsdn)) == arena) {
2008 arena_nthreads_inc(arena, false);
2010 if (tsd_iarena_get(tsdn_tsd(tsdn)) == arena) {
2011 arena_nthreads_inc(arena, true);
2014 ql_new(&arena->tcache_ql);
2015 ql_new(&arena->cache_bin_array_descriptor_ql);
2016 tcache_t *tcache = tcache_get(tsdn_tsd(tsdn));
2017 if (tcache != NULL && tcache->arena == arena) {
2018 ql_elm_new(tcache, link);
2019 ql_tail_insert(&arena->tcache_ql, tcache, link);
2020 cache_bin_array_descriptor_init(
2021 &tcache->cache_bin_array_descriptor,
2022 tcache->bins_small, tcache->bins_large);
2023 ql_tail_insert(&arena->cache_bin_array_descriptor_ql,
2024 &tcache->cache_bin_array_descriptor, link);
2028 for (i = 0; i < NBINS; i++) {
2029 bin_postfork_child(tsdn, &arena->bins[i]);
2031 malloc_mutex_postfork_child(tsdn, &arena->large_mtx);
2032 base_postfork_child(tsdn, arena->base);
2033 malloc_mutex_postfork_child(tsdn, &arena->extent_avail_mtx);
2034 extents_postfork_child(tsdn, &arena->extents_dirty);
2035 extents_postfork_child(tsdn, &arena->extents_muzzy);
2036 extents_postfork_child(tsdn, &arena->extents_retained);
2037 malloc_mutex_postfork_child(tsdn, &arena->extent_grow_mtx);
2038 malloc_mutex_postfork_child(tsdn, &arena->decay_dirty.mtx);
2039 malloc_mutex_postfork_child(tsdn, &arena->decay_muzzy.mtx);
2041 malloc_mutex_postfork_child(tsdn, &arena->tcache_ql_mtx);