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-rw-r--r--deps/jemalloc/src/pac.c587
1 files changed, 587 insertions, 0 deletions
diff --git a/deps/jemalloc/src/pac.c b/deps/jemalloc/src/pac.c
new file mode 100644
index 0000000..53e3d82
--- /dev/null
+++ b/deps/jemalloc/src/pac.c
@@ -0,0 +1,587 @@
+#include "jemalloc/internal/jemalloc_preamble.h"
+#include "jemalloc/internal/jemalloc_internal_includes.h"
+
+#include "jemalloc/internal/pac.h"
+#include "jemalloc/internal/san.h"
+
+static edata_t *pac_alloc_impl(tsdn_t *tsdn, pai_t *self, size_t size,
+ size_t alignment, bool zero, bool guarded, bool frequent_reuse,
+ bool *deferred_work_generated);
+static bool pac_expand_impl(tsdn_t *tsdn, pai_t *self, edata_t *edata,
+ size_t old_size, size_t new_size, bool zero, bool *deferred_work_generated);
+static bool pac_shrink_impl(tsdn_t *tsdn, pai_t *self, edata_t *edata,
+ size_t old_size, size_t new_size, bool *deferred_work_generated);
+static void pac_dalloc_impl(tsdn_t *tsdn, pai_t *self, edata_t *edata,
+ bool *deferred_work_generated);
+static uint64_t pac_time_until_deferred_work(tsdn_t *tsdn, pai_t *self);
+
+static inline void
+pac_decay_data_get(pac_t *pac, extent_state_t state,
+ decay_t **r_decay, pac_decay_stats_t **r_decay_stats, ecache_t **r_ecache) {
+ switch(state) {
+ case extent_state_dirty:
+ *r_decay = &pac->decay_dirty;
+ *r_decay_stats = &pac->stats->decay_dirty;
+ *r_ecache = &pac->ecache_dirty;
+ return;
+ case extent_state_muzzy:
+ *r_decay = &pac->decay_muzzy;
+ *r_decay_stats = &pac->stats->decay_muzzy;
+ *r_ecache = &pac->ecache_muzzy;
+ return;
+ default:
+ unreachable();
+ }
+}
+
+bool
+pac_init(tsdn_t *tsdn, pac_t *pac, base_t *base, emap_t *emap,
+ edata_cache_t *edata_cache, nstime_t *cur_time,
+ size_t pac_oversize_threshold, ssize_t dirty_decay_ms,
+ ssize_t muzzy_decay_ms, pac_stats_t *pac_stats, malloc_mutex_t *stats_mtx) {
+ unsigned ind = base_ind_get(base);
+ /*
+ * Delay coalescing for dirty extents despite the disruptive effect on
+ * memory layout for best-fit extent allocation, since cached extents
+ * are likely to be reused soon after deallocation, and the cost of
+ * merging/splitting extents is non-trivial.
+ */
+ if (ecache_init(tsdn, &pac->ecache_dirty, extent_state_dirty, ind,
+ /* delay_coalesce */ true)) {
+ return true;
+ }
+ /*
+ * Coalesce muzzy extents immediately, because operations on them are in
+ * the critical path much less often than for dirty extents.
+ */
+ if (ecache_init(tsdn, &pac->ecache_muzzy, extent_state_muzzy, ind,
+ /* delay_coalesce */ false)) {
+ return true;
+ }
+ /*
+ * Coalesce retained extents immediately, in part because they will
+ * never be evicted (and therefore there's no opportunity for delayed
+ * coalescing), but also because operations on retained extents are not
+ * in the critical path.
+ */
+ if (ecache_init(tsdn, &pac->ecache_retained, extent_state_retained,
+ ind, /* delay_coalesce */ false)) {
+ return true;
+ }
+ exp_grow_init(&pac->exp_grow);
+ if (malloc_mutex_init(&pac->grow_mtx, "extent_grow",
+ WITNESS_RANK_EXTENT_GROW, malloc_mutex_rank_exclusive)) {
+ return true;
+ }
+ atomic_store_zu(&pac->oversize_threshold, pac_oversize_threshold,
+ ATOMIC_RELAXED);
+ if (decay_init(&pac->decay_dirty, cur_time, dirty_decay_ms)) {
+ return true;
+ }
+ if (decay_init(&pac->decay_muzzy, cur_time, muzzy_decay_ms)) {
+ return true;
+ }
+ if (san_bump_alloc_init(&pac->sba)) {
+ return true;
+ }
+
+ pac->base = base;
+ pac->emap = emap;
+ pac->edata_cache = edata_cache;
+ pac->stats = pac_stats;
+ pac->stats_mtx = stats_mtx;
+ atomic_store_zu(&pac->extent_sn_next, 0, ATOMIC_RELAXED);
+
+ pac->pai.alloc = &pac_alloc_impl;
+ pac->pai.alloc_batch = &pai_alloc_batch_default;
+ pac->pai.expand = &pac_expand_impl;
+ pac->pai.shrink = &pac_shrink_impl;
+ pac->pai.dalloc = &pac_dalloc_impl;
+ pac->pai.dalloc_batch = &pai_dalloc_batch_default;
+ pac->pai.time_until_deferred_work = &pac_time_until_deferred_work;
+
+ return false;
+}
+
+static inline bool
+pac_may_have_muzzy(pac_t *pac) {
+ return pac_decay_ms_get(pac, extent_state_muzzy) != 0;
+}
+
+static edata_t *
+pac_alloc_real(tsdn_t *tsdn, pac_t *pac, ehooks_t *ehooks, size_t size,
+ size_t alignment, bool zero, bool guarded) {
+ assert(!guarded || alignment <= PAGE);
+
+ edata_t *edata = ecache_alloc(tsdn, pac, ehooks, &pac->ecache_dirty,
+ NULL, size, alignment, zero, guarded);
+
+ if (edata == NULL && pac_may_have_muzzy(pac)) {
+ edata = ecache_alloc(tsdn, pac, ehooks, &pac->ecache_muzzy,
+ NULL, size, alignment, zero, guarded);
+ }
+ if (edata == NULL) {
+ edata = ecache_alloc_grow(tsdn, pac, ehooks,
+ &pac->ecache_retained, NULL, size, alignment, zero,
+ guarded);
+ if (config_stats && edata != NULL) {
+ atomic_fetch_add_zu(&pac->stats->pac_mapped, size,
+ ATOMIC_RELAXED);
+ }
+ }
+
+ return edata;
+}
+
+static edata_t *
+pac_alloc_new_guarded(tsdn_t *tsdn, pac_t *pac, ehooks_t *ehooks, size_t size,
+ size_t alignment, bool zero, bool frequent_reuse) {
+ assert(alignment <= PAGE);
+
+ edata_t *edata;
+ if (san_bump_enabled() && frequent_reuse) {
+ edata = san_bump_alloc(tsdn, &pac->sba, pac, ehooks, size,
+ zero);
+ } else {
+ size_t size_with_guards = san_two_side_guarded_sz(size);
+ /* Alloc a non-guarded extent first.*/
+ edata = pac_alloc_real(tsdn, pac, ehooks, size_with_guards,
+ /* alignment */ PAGE, zero, /* guarded */ false);
+ if (edata != NULL) {
+ /* Add guards around it. */
+ assert(edata_size_get(edata) == size_with_guards);
+ san_guard_pages_two_sided(tsdn, ehooks, edata,
+ pac->emap, true);
+ }
+ }
+ assert(edata == NULL || (edata_guarded_get(edata) &&
+ edata_size_get(edata) == size));
+
+ return edata;
+}
+
+static edata_t *
+pac_alloc_impl(tsdn_t *tsdn, pai_t *self, size_t size, size_t alignment,
+ bool zero, bool guarded, bool frequent_reuse,
+ bool *deferred_work_generated) {
+ pac_t *pac = (pac_t *)self;
+ ehooks_t *ehooks = pac_ehooks_get(pac);
+
+ edata_t *edata = NULL;
+ /*
+ * The condition is an optimization - not frequently reused guarded
+ * allocations are never put in the ecache. pac_alloc_real also
+ * doesn't grow retained for guarded allocations. So pac_alloc_real
+ * for such allocations would always return NULL.
+ * */
+ if (!guarded || frequent_reuse) {
+ edata = pac_alloc_real(tsdn, pac, ehooks, size, alignment,
+ zero, guarded);
+ }
+ if (edata == NULL && guarded) {
+ /* No cached guarded extents; creating a new one. */
+ edata = pac_alloc_new_guarded(tsdn, pac, ehooks, size,
+ alignment, zero, frequent_reuse);
+ }
+
+ return edata;
+}
+
+static bool
+pac_expand_impl(tsdn_t *tsdn, pai_t *self, edata_t *edata, size_t old_size,
+ size_t new_size, bool zero, bool *deferred_work_generated) {
+ pac_t *pac = (pac_t *)self;
+ ehooks_t *ehooks = pac_ehooks_get(pac);
+
+ size_t mapped_add = 0;
+ size_t expand_amount = new_size - old_size;
+
+ if (ehooks_merge_will_fail(ehooks)) {
+ return true;
+ }
+ edata_t *trail = ecache_alloc(tsdn, pac, ehooks, &pac->ecache_dirty,
+ edata, expand_amount, PAGE, zero, /* guarded*/ false);
+ if (trail == NULL) {
+ trail = ecache_alloc(tsdn, pac, ehooks, &pac->ecache_muzzy,
+ edata, expand_amount, PAGE, zero, /* guarded*/ false);
+ }
+ if (trail == NULL) {
+ trail = ecache_alloc_grow(tsdn, pac, ehooks,
+ &pac->ecache_retained, edata, expand_amount, PAGE, zero,
+ /* guarded */ false);
+ mapped_add = expand_amount;
+ }
+ if (trail == NULL) {
+ return true;
+ }
+ if (extent_merge_wrapper(tsdn, pac, ehooks, edata, trail)) {
+ extent_dalloc_wrapper(tsdn, pac, ehooks, trail);
+ return true;
+ }
+ if (config_stats && mapped_add > 0) {
+ atomic_fetch_add_zu(&pac->stats->pac_mapped, mapped_add,
+ ATOMIC_RELAXED);
+ }
+ return false;
+}
+
+static bool
+pac_shrink_impl(tsdn_t *tsdn, pai_t *self, edata_t *edata, size_t old_size,
+ size_t new_size, bool *deferred_work_generated) {
+ pac_t *pac = (pac_t *)self;
+ ehooks_t *ehooks = pac_ehooks_get(pac);
+
+ size_t shrink_amount = old_size - new_size;
+
+ if (ehooks_split_will_fail(ehooks)) {
+ return true;
+ }
+
+ edata_t *trail = extent_split_wrapper(tsdn, pac, ehooks, edata,
+ new_size, shrink_amount, /* holding_core_locks */ false);
+ if (trail == NULL) {
+ return true;
+ }
+ ecache_dalloc(tsdn, pac, ehooks, &pac->ecache_dirty, trail);
+ *deferred_work_generated = true;
+ return false;
+}
+
+static void
+pac_dalloc_impl(tsdn_t *tsdn, pai_t *self, edata_t *edata,
+ bool *deferred_work_generated) {
+ pac_t *pac = (pac_t *)self;
+ ehooks_t *ehooks = pac_ehooks_get(pac);
+
+ if (edata_guarded_get(edata)) {
+ /*
+ * Because cached guarded extents do exact fit only, large
+ * guarded extents are restored on dalloc eagerly (otherwise
+ * they will not be reused efficiently). Slab sizes have a
+ * limited number of size classes, and tend to cycle faster.
+ *
+ * In the case where coalesce is restrained (VirtualFree on
+ * Windows), guarded extents are also not cached -- otherwise
+ * during arena destroy / reset, the retained extents would not
+ * be whole regions (i.e. they are split between regular and
+ * guarded).
+ */
+ if (!edata_slab_get(edata) || !maps_coalesce) {
+ assert(edata_size_get(edata) >= SC_LARGE_MINCLASS ||
+ !maps_coalesce);
+ san_unguard_pages_two_sided(tsdn, ehooks, edata,
+ pac->emap);
+ }
+ }
+
+ ecache_dalloc(tsdn, pac, ehooks, &pac->ecache_dirty, edata);
+ /* Purging of deallocated pages is deferred */
+ *deferred_work_generated = true;
+}
+
+static inline uint64_t
+pac_ns_until_purge(tsdn_t *tsdn, decay_t *decay, size_t npages) {
+ if (malloc_mutex_trylock(tsdn, &decay->mtx)) {
+ /* Use minimal interval if decay is contended. */
+ return BACKGROUND_THREAD_DEFERRED_MIN;
+ }
+ uint64_t result = decay_ns_until_purge(decay, npages,
+ ARENA_DEFERRED_PURGE_NPAGES_THRESHOLD);
+
+ malloc_mutex_unlock(tsdn, &decay->mtx);
+ return result;
+}
+
+static uint64_t
+pac_time_until_deferred_work(tsdn_t *tsdn, pai_t *self) {
+ uint64_t time;
+ pac_t *pac = (pac_t *)self;
+
+ time = pac_ns_until_purge(tsdn,
+ &pac->decay_dirty,
+ ecache_npages_get(&pac->ecache_dirty));
+ if (time == BACKGROUND_THREAD_DEFERRED_MIN) {
+ return time;
+ }
+
+ uint64_t muzzy = pac_ns_until_purge(tsdn,
+ &pac->decay_muzzy,
+ ecache_npages_get(&pac->ecache_muzzy));
+ if (muzzy < time) {
+ time = muzzy;
+ }
+ return time;
+}
+
+bool
+pac_retain_grow_limit_get_set(tsdn_t *tsdn, pac_t *pac, size_t *old_limit,
+ size_t *new_limit) {
+ pszind_t new_ind JEMALLOC_CC_SILENCE_INIT(0);
+ if (new_limit != NULL) {
+ size_t limit = *new_limit;
+ /* Grow no more than the new limit. */
+ if ((new_ind = sz_psz2ind(limit + 1) - 1) >= SC_NPSIZES) {
+ return true;
+ }
+ }
+
+ malloc_mutex_lock(tsdn, &pac->grow_mtx);
+ if (old_limit != NULL) {
+ *old_limit = sz_pind2sz(pac->exp_grow.limit);
+ }
+ if (new_limit != NULL) {
+ pac->exp_grow.limit = new_ind;
+ }
+ malloc_mutex_unlock(tsdn, &pac->grow_mtx);
+
+ return false;
+}
+
+static size_t
+pac_stash_decayed(tsdn_t *tsdn, pac_t *pac, ecache_t *ecache,
+ size_t npages_limit, size_t npages_decay_max,
+ edata_list_inactive_t *result) {
+ witness_assert_depth_to_rank(tsdn_witness_tsdp_get(tsdn),
+ WITNESS_RANK_CORE, 0);
+ ehooks_t *ehooks = pac_ehooks_get(pac);
+
+ /* Stash extents according to npages_limit. */
+ size_t nstashed = 0;
+ while (nstashed < npages_decay_max) {
+ edata_t *edata = ecache_evict(tsdn, pac, ehooks, ecache,
+ npages_limit);
+ if (edata == NULL) {
+ break;
+ }
+ edata_list_inactive_append(result, edata);
+ nstashed += edata_size_get(edata) >> LG_PAGE;
+ }
+ return nstashed;
+}
+
+static size_t
+pac_decay_stashed(tsdn_t *tsdn, pac_t *pac, decay_t *decay,
+ pac_decay_stats_t *decay_stats, ecache_t *ecache, bool fully_decay,
+ edata_list_inactive_t *decay_extents) {
+ bool err;
+
+ size_t nmadvise = 0;
+ size_t nunmapped = 0;
+ size_t npurged = 0;
+
+ ehooks_t *ehooks = pac_ehooks_get(pac);
+
+ bool try_muzzy = !fully_decay
+ && pac_decay_ms_get(pac, extent_state_muzzy) != 0;
+
+ for (edata_t *edata = edata_list_inactive_first(decay_extents); edata !=
+ NULL; edata = edata_list_inactive_first(decay_extents)) {
+ edata_list_inactive_remove(decay_extents, edata);
+
+ size_t size = edata_size_get(edata);
+ size_t npages = size >> LG_PAGE;
+
+ nmadvise++;
+ npurged += npages;
+
+ switch (ecache->state) {
+ case extent_state_active:
+ not_reached();
+ case extent_state_dirty:
+ if (try_muzzy) {
+ err = extent_purge_lazy_wrapper(tsdn, ehooks,
+ edata, /* offset */ 0, size);
+ if (!err) {
+ ecache_dalloc(tsdn, pac, ehooks,
+ &pac->ecache_muzzy, edata);
+ break;
+ }
+ }
+ JEMALLOC_FALLTHROUGH;
+ case extent_state_muzzy:
+ extent_dalloc_wrapper(tsdn, pac, ehooks, edata);
+ nunmapped += npages;
+ break;
+ case extent_state_retained:
+ default:
+ not_reached();
+ }
+ }
+
+ if (config_stats) {
+ LOCKEDINT_MTX_LOCK(tsdn, *pac->stats_mtx);
+ locked_inc_u64(tsdn, LOCKEDINT_MTX(*pac->stats_mtx),
+ &decay_stats->npurge, 1);
+ locked_inc_u64(tsdn, LOCKEDINT_MTX(*pac->stats_mtx),
+ &decay_stats->nmadvise, nmadvise);
+ locked_inc_u64(tsdn, LOCKEDINT_MTX(*pac->stats_mtx),
+ &decay_stats->purged, npurged);
+ LOCKEDINT_MTX_UNLOCK(tsdn, *pac->stats_mtx);
+ atomic_fetch_sub_zu(&pac->stats->pac_mapped,
+ nunmapped << LG_PAGE, ATOMIC_RELAXED);
+ }
+
+ return npurged;
+}
+
+/*
+ * npages_limit: Decay at most npages_decay_max pages without violating the
+ * invariant: (ecache_npages_get(ecache) >= npages_limit). We need an upper
+ * bound on number of pages in order to prevent unbounded growth (namely in
+ * stashed), otherwise unbounded new pages could be added to extents during the
+ * current decay run, so that the purging thread never finishes.
+ */
+static void
+pac_decay_to_limit(tsdn_t *tsdn, pac_t *pac, decay_t *decay,
+ pac_decay_stats_t *decay_stats, ecache_t *ecache, bool fully_decay,
+ size_t npages_limit, size_t npages_decay_max) {
+ witness_assert_depth_to_rank(tsdn_witness_tsdp_get(tsdn),
+ WITNESS_RANK_CORE, 1);
+
+ if (decay->purging || npages_decay_max == 0) {
+ return;
+ }
+ decay->purging = true;
+ malloc_mutex_unlock(tsdn, &decay->mtx);
+
+ edata_list_inactive_t decay_extents;
+ edata_list_inactive_init(&decay_extents);
+ size_t npurge = pac_stash_decayed(tsdn, pac, ecache, npages_limit,
+ npages_decay_max, &decay_extents);
+ if (npurge != 0) {
+ size_t npurged = pac_decay_stashed(tsdn, pac, decay,
+ decay_stats, ecache, fully_decay, &decay_extents);
+ assert(npurged == npurge);
+ }
+
+ malloc_mutex_lock(tsdn, &decay->mtx);
+ decay->purging = false;
+}
+
+void
+pac_decay_all(tsdn_t *tsdn, pac_t *pac, decay_t *decay,
+ pac_decay_stats_t *decay_stats, ecache_t *ecache, bool fully_decay) {
+ malloc_mutex_assert_owner(tsdn, &decay->mtx);
+ pac_decay_to_limit(tsdn, pac, decay, decay_stats, ecache, fully_decay,
+ /* npages_limit */ 0, ecache_npages_get(ecache));
+}
+
+static void
+pac_decay_try_purge(tsdn_t *tsdn, pac_t *pac, decay_t *decay,
+ pac_decay_stats_t *decay_stats, ecache_t *ecache,
+ size_t current_npages, size_t npages_limit) {
+ if (current_npages > npages_limit) {
+ pac_decay_to_limit(tsdn, pac, decay, decay_stats, ecache,
+ /* fully_decay */ false, npages_limit,
+ current_npages - npages_limit);
+ }
+}
+
+bool
+pac_maybe_decay_purge(tsdn_t *tsdn, pac_t *pac, decay_t *decay,
+ pac_decay_stats_t *decay_stats, ecache_t *ecache,
+ pac_purge_eagerness_t eagerness) {
+ malloc_mutex_assert_owner(tsdn, &decay->mtx);
+
+ /* Purge all or nothing if the option is disabled. */
+ ssize_t decay_ms = decay_ms_read(decay);
+ if (decay_ms <= 0) {
+ if (decay_ms == 0) {
+ pac_decay_to_limit(tsdn, pac, decay, decay_stats,
+ ecache, /* fully_decay */ false,
+ /* npages_limit */ 0, ecache_npages_get(ecache));
+ }
+ return false;
+ }
+
+ /*
+ * If the deadline has been reached, advance to the current epoch and
+ * purge to the new limit if necessary. Note that dirty pages created
+ * during the current epoch are not subject to purge until a future
+ * epoch, so as a result purging only happens during epoch advances, or
+ * being triggered by background threads (scheduled event).
+ */
+ nstime_t time;
+ nstime_init_update(&time);
+ size_t npages_current = ecache_npages_get(ecache);
+ bool epoch_advanced = decay_maybe_advance_epoch(decay, &time,
+ npages_current);
+ if (eagerness == PAC_PURGE_ALWAYS
+ || (epoch_advanced && eagerness == PAC_PURGE_ON_EPOCH_ADVANCE)) {
+ size_t npages_limit = decay_npages_limit_get(decay);
+ pac_decay_try_purge(tsdn, pac, decay, decay_stats, ecache,
+ npages_current, npages_limit);
+ }
+
+ return epoch_advanced;
+}
+
+bool
+pac_decay_ms_set(tsdn_t *tsdn, pac_t *pac, extent_state_t state,
+ ssize_t decay_ms, pac_purge_eagerness_t eagerness) {
+ decay_t *decay;
+ pac_decay_stats_t *decay_stats;
+ ecache_t *ecache;
+ pac_decay_data_get(pac, state, &decay, &decay_stats, &ecache);
+
+ if (!decay_ms_valid(decay_ms)) {
+ return true;
+ }
+
+ malloc_mutex_lock(tsdn, &decay->mtx);
+ /*
+ * Restart decay backlog from scratch, which may cause many dirty pages
+ * to be immediately purged. It would conceptually be possible to map
+ * the old backlog onto the new backlog, but there is no justification
+ * for such complexity since decay_ms changes are intended to be
+ * infrequent, either between the {-1, 0, >0} states, or a one-time
+ * arbitrary change during initial arena configuration.
+ */
+ nstime_t cur_time;
+ nstime_init_update(&cur_time);
+ decay_reinit(decay, &cur_time, decay_ms);
+ pac_maybe_decay_purge(tsdn, pac, decay, decay_stats, ecache, eagerness);
+ malloc_mutex_unlock(tsdn, &decay->mtx);
+
+ return false;
+}
+
+ssize_t
+pac_decay_ms_get(pac_t *pac, extent_state_t state) {
+ decay_t *decay;
+ pac_decay_stats_t *decay_stats;
+ ecache_t *ecache;
+ pac_decay_data_get(pac, state, &decay, &decay_stats, &ecache);
+ return decay_ms_read(decay);
+}
+
+void
+pac_reset(tsdn_t *tsdn, pac_t *pac) {
+ /*
+ * No-op for now; purging is still done at the arena-level. It should
+ * get moved in here, though.
+ */
+ (void)tsdn;
+ (void)pac;
+}
+
+void
+pac_destroy(tsdn_t *tsdn, pac_t *pac) {
+ assert(ecache_npages_get(&pac->ecache_dirty) == 0);
+ assert(ecache_npages_get(&pac->ecache_muzzy) == 0);
+ /*
+ * Iterate over the retained extents and destroy them. This gives the
+ * extent allocator underlying the extent hooks an opportunity to unmap
+ * all retained memory without having to keep its own metadata
+ * structures. In practice, virtual memory for dss-allocated extents is
+ * leaked here, so best practice is to avoid dss for arenas to be
+ * destroyed, or provide custom extent hooks that track retained
+ * dss-based extents for later reuse.
+ */
+ ehooks_t *ehooks = pac_ehooks_get(pac);
+ edata_t *edata;
+ while ((edata = ecache_evict(tsdn, pac, ehooks,
+ &pac->ecache_retained, 0)) != NULL) {
+ extent_destroy_wrapper(tsdn, pac, ehooks, edata);
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-27 03:38:11 +0000