1 files changed, 179 insertions, 0 deletions
diff --git a/deps/jemalloc/include/jemalloc/internal/pac.h b/deps/jemalloc/include/jemalloc/internal/pac.h
new file mode 100644
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--- /dev/null
+++ b/deps/jemalloc/include/jemalloc/internal/pac.h
@@ -0,0 +1,179 @@
+#ifndef JEMALLOC_INTERNAL_PAC_H
+#define JEMALLOC_INTERNAL_PAC_H
+
+#include "jemalloc/internal/exp_grow.h"
+#include "jemalloc/internal/pai.h"
+#include "san_bump.h"
+
+
+/*
+ * Page allocator classic; an implementation of the PAI interface that:
+ * - Can be used for arenas with custom extent hooks.
+ * - Can always satisfy any allocation request (including highly-fragmentary
+ *   ones).
+ * - Can use efficient OS-level zeroing primitives for demand-filled pages.
+ */
+
+/* How "eager" decay/purging should be. */
+enum pac_purge_eagerness_e {
+	PAC_PURGE_ALWAYS,
+	PAC_PURGE_NEVER,
+	PAC_PURGE_ON_EPOCH_ADVANCE
+};
+typedef enum pac_purge_eagerness_e pac_purge_eagerness_t;
+
+typedef struct pac_decay_stats_s pac_decay_stats_t;
+struct pac_decay_stats_s {
+	/* Total number of purge sweeps. */
+	locked_u64_t npurge;
+	/* Total number of madvise calls made. */
+	locked_u64_t nmadvise;
+	/* Total number of pages purged. */
+	locked_u64_t purged;
+};
+
+typedef struct pac_estats_s pac_estats_t;
+struct pac_estats_s {
+	/*
+	 * Stats for a given index in the range [0, SC_NPSIZES] in the various
+	 * ecache_ts.
+	 * We track both bytes and # of extents: two extents in the same bucket
+	 * may have different sizes if adjacent size classes differ by more than
+	 * a page, so bytes cannot always be derived from # of extents.
+	 */
+	size_t ndirty;
+	size_t dirty_bytes;
+	size_t nmuzzy;
+	size_t muzzy_bytes;
+	size_t nretained;
+	size_t retained_bytes;
+};
+
+typedef struct pac_stats_s pac_stats_t;
+struct pac_stats_s {
+	pac_decay_stats_t decay_dirty;
+	pac_decay_stats_t decay_muzzy;
+
+	/*
+	 * Number of unused virtual memory bytes currently retained.  Retained
+	 * bytes are technically mapped (though always decommitted or purged),
+	 * but they are excluded from the mapped statistic (above).
+	 */
+	size_t retained; /* Derived. */
+
+	/*
+	 * Number of bytes currently mapped, excluding retained memory (and any
+	 * base-allocated memory, which is tracked by the arena stats).
+	 *
+	 * We name this "pac_mapped" to avoid confusion with the arena_stats
+	 * "mapped".
+	 */
+	atomic_zu_t pac_mapped;
+
+	/* VM space had to be leaked (undocumented).  Normally 0. */
+	atomic_zu_t abandoned_vm;
+};
+
+typedef struct pac_s pac_t;
+struct pac_s {
+	/*
+	 * Must be the first member (we convert it to a PAC given only a
+	 * pointer).  The handle to the allocation interface.
+	 */
+	pai_t pai;
+	/*
+	 * Collections of extents that were previously allocated.  These are
+	 * used when allocating extents, in an attempt to re-use address space.
+	 *
+	 * Synchronization: internal.
+	 */
+	ecache_t ecache_dirty;
+	ecache_t ecache_muzzy;
+	ecache_t ecache_retained;
+
+	base_t *base;
+	emap_t *emap;
+	edata_cache_t *edata_cache;
+
+	/* The grow info for the retained ecache. */
+	exp_grow_t exp_grow;
+	malloc_mutex_t grow_mtx;
+
+	/* Special allocator for guarded frequently reused extents. */
+	san_bump_alloc_t sba;
+
+	/* How large extents should be before getting auto-purged. */
+	atomic_zu_t oversize_threshold;
+
+	/*
+	 * Decay-based purging state, responsible for scheduling extent state
+	 * transitions.
+	 *
+	 * Synchronization: via the internal mutex.
+	 */
+	decay_t decay_dirty; /* dirty --> muzzy */
+	decay_t decay_muzzy; /* muzzy --> retained */
+
+	malloc_mutex_t *stats_mtx;
+	pac_stats_t *stats;
+
+	/* Extent serial number generator state. */
+	atomic_zu_t extent_sn_next;
+};
+
+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 oversize_threshold,
+    ssize_t dirty_decay_ms, ssize_t muzzy_decay_ms, pac_stats_t *pac_stats,
+    malloc_mutex_t *stats_mtx);
+
+static inline size_t
+pac_mapped(pac_t *pac) {
+	return atomic_load_zu(&pac->stats->pac_mapped, ATOMIC_RELAXED);
+}
+
+static inline ehooks_t *
+pac_ehooks_get(pac_t *pac) {
+	return base_ehooks_get(pac->base);
+}
+
+/*
+ * All purging functions require holding decay->mtx.  This is one of the few
+ * places external modules are allowed to peek inside pa_shard_t internals.
+ */
+
+/*
+ * Decays the number of pages currently in the ecache.  This might not leave the
+ * ecache empty if other threads are inserting dirty objects into it
+ * concurrently with the call.
+ */
+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);
+/*
+ * Updates decay settings for the current time, and conditionally purges in
+ * response (depending on decay_purge_setting).  Returns whether or not the
+ * epoch advanced.
+ */
+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);
+
+/*
+ * Gets / sets the maximum amount that we'll grow an arena down the
+ * grow-retained pathways (unless forced to by an allocaction request).
+ *
+ * Set new_limit to NULL if it's just a query, or old_limit to NULL if you don't
+ * care about the previous value.
+ *
+ * Returns true on error (if the new limit is not valid).
+ */
+bool pac_retain_grow_limit_get_set(tsdn_t *tsdn, pac_t *pac, size_t *old_limit,
+    size_t *new_limit);
+
+bool pac_decay_ms_set(tsdn_t *tsdn, pac_t *pac, extent_state_t state,
+    ssize_t decay_ms, pac_purge_eagerness_t eagerness);
+ssize_t pac_decay_ms_get(pac_t *pac, extent_state_t state);
+
+void pac_reset(tsdn_t *tsdn, pac_t *pac);
+void pac_destroy(tsdn_t *tsdn, pac_t *pac);
+
+#endif /* JEMALLOC_INTERNAL_PAC_H */