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-rw-r--r--deps/jemalloc/src/eset.c282
1 files changed, 282 insertions, 0 deletions
diff --git a/deps/jemalloc/src/eset.c b/deps/jemalloc/src/eset.c
new file mode 100644
index 0000000..6f8f335
--- /dev/null
+++ b/deps/jemalloc/src/eset.c
@@ -0,0 +1,282 @@
+#include "jemalloc/internal/jemalloc_preamble.h"
+#include "jemalloc/internal/jemalloc_internal_includes.h"
+
+#include "jemalloc/internal/eset.h"
+
+#define ESET_NPSIZES (SC_NPSIZES + 1)
+
+static void
+eset_bin_init(eset_bin_t *bin) {
+ edata_heap_new(&bin->heap);
+ /*
+ * heap_min doesn't need initialization; it gets filled in when the bin
+ * goes from non-empty to empty.
+ */
+}
+
+static void
+eset_bin_stats_init(eset_bin_stats_t *bin_stats) {
+ atomic_store_zu(&bin_stats->nextents, 0, ATOMIC_RELAXED);
+ atomic_store_zu(&bin_stats->nbytes, 0, ATOMIC_RELAXED);
+}
+
+void
+eset_init(eset_t *eset, extent_state_t state) {
+ for (unsigned i = 0; i < ESET_NPSIZES; i++) {
+ eset_bin_init(&eset->bins[i]);
+ eset_bin_stats_init(&eset->bin_stats[i]);
+ }
+ fb_init(eset->bitmap, ESET_NPSIZES);
+ edata_list_inactive_init(&eset->lru);
+ eset->state = state;
+}
+
+size_t
+eset_npages_get(eset_t *eset) {
+ return atomic_load_zu(&eset->npages, ATOMIC_RELAXED);
+}
+
+size_t
+eset_nextents_get(eset_t *eset, pszind_t pind) {
+ return atomic_load_zu(&eset->bin_stats[pind].nextents, ATOMIC_RELAXED);
+}
+
+size_t
+eset_nbytes_get(eset_t *eset, pszind_t pind) {
+ return atomic_load_zu(&eset->bin_stats[pind].nbytes, ATOMIC_RELAXED);
+}
+
+static void
+eset_stats_add(eset_t *eset, pszind_t pind, size_t sz) {
+ size_t cur = atomic_load_zu(&eset->bin_stats[pind].nextents,
+ ATOMIC_RELAXED);
+ atomic_store_zu(&eset->bin_stats[pind].nextents, cur + 1,
+ ATOMIC_RELAXED);
+ cur = atomic_load_zu(&eset->bin_stats[pind].nbytes, ATOMIC_RELAXED);
+ atomic_store_zu(&eset->bin_stats[pind].nbytes, cur + sz,
+ ATOMIC_RELAXED);
+}
+
+static void
+eset_stats_sub(eset_t *eset, pszind_t pind, size_t sz) {
+ size_t cur = atomic_load_zu(&eset->bin_stats[pind].nextents,
+ ATOMIC_RELAXED);
+ atomic_store_zu(&eset->bin_stats[pind].nextents, cur - 1,
+ ATOMIC_RELAXED);
+ cur = atomic_load_zu(&eset->bin_stats[pind].nbytes, ATOMIC_RELAXED);
+ atomic_store_zu(&eset->bin_stats[pind].nbytes, cur - sz,
+ ATOMIC_RELAXED);
+}
+
+void
+eset_insert(eset_t *eset, edata_t *edata) {
+ assert(edata_state_get(edata) == eset->state);
+
+ size_t size = edata_size_get(edata);
+ size_t psz = sz_psz_quantize_floor(size);
+ pszind_t pind = sz_psz2ind(psz);
+
+ edata_cmp_summary_t edata_cmp_summary = edata_cmp_summary_get(edata);
+ if (edata_heap_empty(&eset->bins[pind].heap)) {
+ fb_set(eset->bitmap, ESET_NPSIZES, (size_t)pind);
+ /* Only element is automatically the min element. */
+ eset->bins[pind].heap_min = edata_cmp_summary;
+ } else {
+ /*
+ * There's already a min element; update the summary if we're
+ * about to insert a lower one.
+ */
+ if (edata_cmp_summary_comp(edata_cmp_summary,
+ eset->bins[pind].heap_min) < 0) {
+ eset->bins[pind].heap_min = edata_cmp_summary;
+ }
+ }
+ edata_heap_insert(&eset->bins[pind].heap, edata);
+
+ if (config_stats) {
+ eset_stats_add(eset, pind, size);
+ }
+
+ edata_list_inactive_append(&eset->lru, edata);
+ size_t npages = size >> LG_PAGE;
+ /*
+ * All modifications to npages hold the mutex (as asserted above), so we
+ * don't need an atomic fetch-add; we can get by with a load followed by
+ * a store.
+ */
+ size_t cur_eset_npages =
+ atomic_load_zu(&eset->npages, ATOMIC_RELAXED);
+ atomic_store_zu(&eset->npages, cur_eset_npages + npages,
+ ATOMIC_RELAXED);
+}
+
+void
+eset_remove(eset_t *eset, edata_t *edata) {
+ assert(edata_state_get(edata) == eset->state ||
+ edata_state_in_transition(edata_state_get(edata)));
+
+ size_t size = edata_size_get(edata);
+ size_t psz = sz_psz_quantize_floor(size);
+ pszind_t pind = sz_psz2ind(psz);
+ if (config_stats) {
+ eset_stats_sub(eset, pind, size);
+ }
+
+ edata_cmp_summary_t edata_cmp_summary = edata_cmp_summary_get(edata);
+ edata_heap_remove(&eset->bins[pind].heap, edata);
+ if (edata_heap_empty(&eset->bins[pind].heap)) {
+ fb_unset(eset->bitmap, ESET_NPSIZES, (size_t)pind);
+ } else {
+ /*
+ * This is a little weird; we compare if the summaries are
+ * equal, rather than if the edata we removed was the heap
+ * minimum. The reason why is that getting the heap minimum
+ * can cause a pairing heap merge operation. We can avoid this
+ * if we only update the min if it's changed, in which case the
+ * summaries of the removed element and the min element should
+ * compare equal.
+ */
+ if (edata_cmp_summary_comp(edata_cmp_summary,
+ eset->bins[pind].heap_min) == 0) {
+ eset->bins[pind].heap_min = edata_cmp_summary_get(
+ edata_heap_first(&eset->bins[pind].heap));
+ }
+ }
+ edata_list_inactive_remove(&eset->lru, edata);
+ size_t npages = size >> LG_PAGE;
+ /*
+ * As in eset_insert, we hold eset->mtx and so don't need atomic
+ * operations for updating eset->npages.
+ */
+ size_t cur_extents_npages =
+ atomic_load_zu(&eset->npages, ATOMIC_RELAXED);
+ assert(cur_extents_npages >= npages);
+ atomic_store_zu(&eset->npages,
+ cur_extents_npages - (size >> LG_PAGE), ATOMIC_RELAXED);
+}
+
+/*
+ * Find an extent with size [min_size, max_size) to satisfy the alignment
+ * requirement. For each size, try only the first extent in the heap.
+ */
+static edata_t *
+eset_fit_alignment(eset_t *eset, size_t min_size, size_t max_size,
+ size_t alignment) {
+ pszind_t pind = sz_psz2ind(sz_psz_quantize_ceil(min_size));
+ pszind_t pind_max = sz_psz2ind(sz_psz_quantize_ceil(max_size));
+
+ for (pszind_t i =
+ (pszind_t)fb_ffs(eset->bitmap, ESET_NPSIZES, (size_t)pind);
+ i < pind_max;
+ i = (pszind_t)fb_ffs(eset->bitmap, ESET_NPSIZES, (size_t)i + 1)) {
+ assert(i < SC_NPSIZES);
+ assert(!edata_heap_empty(&eset->bins[i].heap));
+ edata_t *edata = edata_heap_first(&eset->bins[i].heap);
+ uintptr_t base = (uintptr_t)edata_base_get(edata);
+ size_t candidate_size = edata_size_get(edata);
+ assert(candidate_size >= min_size);
+
+ uintptr_t next_align = ALIGNMENT_CEILING((uintptr_t)base,
+ PAGE_CEILING(alignment));
+ if (base > next_align || base + candidate_size <= next_align) {
+ /* Overflow or not crossing the next alignment. */
+ continue;
+ }
+
+ size_t leadsize = next_align - base;
+ if (candidate_size - leadsize >= min_size) {
+ return edata;
+ }
+ }
+
+ return NULL;
+}
+
+/*
+ * Do first-fit extent selection, i.e. select the oldest/lowest extent that is
+ * large enough.
+ *
+ * lg_max_fit is the (log of the) maximum ratio between the requested size and
+ * the returned size that we'll allow. This can reduce fragmentation by
+ * avoiding reusing and splitting large extents for smaller sizes. In practice,
+ * it's set to opt_lg_extent_max_active_fit for the dirty eset and SC_PTR_BITS
+ * for others.
+ */
+static edata_t *
+eset_first_fit(eset_t *eset, size_t size, bool exact_only,
+ unsigned lg_max_fit) {
+ edata_t *ret = NULL;
+ edata_cmp_summary_t ret_summ JEMALLOC_CC_SILENCE_INIT({0});
+
+ pszind_t pind = sz_psz2ind(sz_psz_quantize_ceil(size));
+
+ if (exact_only) {
+ return edata_heap_empty(&eset->bins[pind].heap) ? NULL :
+ edata_heap_first(&eset->bins[pind].heap);
+ }
+
+ for (pszind_t i =
+ (pszind_t)fb_ffs(eset->bitmap, ESET_NPSIZES, (size_t)pind);
+ i < ESET_NPSIZES;
+ i = (pszind_t)fb_ffs(eset->bitmap, ESET_NPSIZES, (size_t)i + 1)) {
+ assert(!edata_heap_empty(&eset->bins[i].heap));
+ if (lg_max_fit == SC_PTR_BITS) {
+ /*
+ * We'll shift by this below, and shifting out all the
+ * bits is undefined. Decreasing is safe, since the
+ * page size is larger than 1 byte.
+ */
+ lg_max_fit = SC_PTR_BITS - 1;
+ }
+ if ((sz_pind2sz(i) >> lg_max_fit) > size) {
+ break;
+ }
+ if (ret == NULL || edata_cmp_summary_comp(
+ eset->bins[i].heap_min, ret_summ) < 0) {
+ /*
+ * We grab the edata as early as possible, even though
+ * we might change it later. Practically, a large
+ * portion of eset_fit calls succeed at the first valid
+ * index, so this doesn't cost much, and we get the
+ * effect of prefetching the edata as early as possible.
+ */
+ edata_t *edata = edata_heap_first(&eset->bins[i].heap);
+ assert(edata_size_get(edata) >= size);
+ assert(ret == NULL || edata_snad_comp(edata, ret) < 0);
+ assert(ret == NULL || edata_cmp_summary_comp(
+ eset->bins[i].heap_min,
+ edata_cmp_summary_get(edata)) == 0);
+ ret = edata;
+ ret_summ = eset->bins[i].heap_min;
+ }
+ if (i == SC_NPSIZES) {
+ break;
+ }
+ assert(i < SC_NPSIZES);
+ }
+
+ return ret;
+}
+
+edata_t *
+eset_fit(eset_t *eset, size_t esize, size_t alignment, bool exact_only,
+ unsigned lg_max_fit) {
+ size_t max_size = esize + PAGE_CEILING(alignment) - PAGE;
+ /* Beware size_t wrap-around. */
+ if (max_size < esize) {
+ return NULL;
+ }
+
+ edata_t *edata = eset_first_fit(eset, max_size, exact_only, lg_max_fit);
+
+ if (alignment > PAGE && edata == NULL) {
+ /*
+ * max_size guarantees the alignment requirement but is rather
+ * pessimistic. Next we try to satisfy the aligned allocation
+ * with sizes in [esize, max_size).
+ */
+ edata = eset_fit_alignment(eset, esize, max_size, alignment);
+ }
+
+ return edata;
+}