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-rw-r--r--src/ck_hs.c941
1 files changed, 941 insertions, 0 deletions
diff --git a/src/ck_hs.c b/src/ck_hs.c
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--- /dev/null
+++ b/src/ck_hs.c
@@ -0,0 +1,941 @@
+/*
+ * Copyright 2012-2015 Samy Al Bahra.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <ck_cc.h>
+#include <ck_hs.h>
+#include <ck_limits.h>
+#include <ck_md.h>
+#include <ck_pr.h>
+#include <ck_stdint.h>
+#include <ck_stdbool.h>
+#include <ck_string.h>
+
+#include "ck_internal.h"
+
+#ifndef CK_HS_PROBE_L1_SHIFT
+#define CK_HS_PROBE_L1_SHIFT 3ULL
+#endif /* CK_HS_PROBE_L1_SHIFT */
+
+#define CK_HS_PROBE_L1 (1 << CK_HS_PROBE_L1_SHIFT)
+#define CK_HS_PROBE_L1_MASK (CK_HS_PROBE_L1 - 1)
+
+#ifndef CK_HS_PROBE_L1_DEFAULT
+#define CK_HS_PROBE_L1_DEFAULT CK_MD_CACHELINE
+#endif
+
+#define CK_HS_VMA_MASK ((uintptr_t)((1ULL << CK_MD_VMA_BITS) - 1))
+#define CK_HS_VMA(x) \
+ ((void *)((uintptr_t)(x) & CK_HS_VMA_MASK))
+
+#define CK_HS_EMPTY NULL
+#define CK_HS_TOMBSTONE ((void *)~(uintptr_t)0)
+#define CK_HS_G (2)
+#define CK_HS_G_MASK (CK_HS_G - 1)
+
+#if defined(CK_F_PR_LOAD_8) && defined(CK_F_PR_STORE_8)
+#define CK_HS_WORD uint8_t
+#define CK_HS_WORD_MAX UINT8_MAX
+#define CK_HS_STORE(x, y) ck_pr_store_8(x, y)
+#define CK_HS_LOAD(x) ck_pr_load_8(x)
+#elif defined(CK_F_PR_LOAD_16) && defined(CK_F_PR_STORE_16)
+#define CK_HS_WORD uint16_t
+#define CK_HS_WORD_MAX UINT16_MAX
+#define CK_HS_STORE(x, y) ck_pr_store_16(x, y)
+#define CK_HS_LOAD(x) ck_pr_load_16(x)
+#elif defined(CK_F_PR_LOAD_32) && defined(CK_F_PR_STORE_32)
+#define CK_HS_WORD uint32_t
+#define CK_HS_WORD_MAX UINT32_MAX
+#define CK_HS_STORE(x, y) ck_pr_store_32(x, y)
+#define CK_HS_LOAD(x) ck_pr_load_32(x)
+#else
+#error "ck_hs is not supported on your platform."
+#endif
+
+enum ck_hs_probe_behavior {
+ CK_HS_PROBE = 0, /* Default behavior. */
+ CK_HS_PROBE_TOMBSTONE, /* Short-circuit on tombstone. */
+ CK_HS_PROBE_INSERT /* Short-circuit on probe bound if tombstone found. */
+};
+
+struct ck_hs_map {
+ unsigned int generation[CK_HS_G];
+ unsigned int probe_maximum;
+ unsigned long mask;
+ unsigned long step;
+ unsigned int probe_limit;
+ unsigned int tombstones;
+ unsigned long n_entries;
+ unsigned long capacity;
+ unsigned long size;
+ CK_HS_WORD *probe_bound;
+ const void **entries;
+};
+
+static inline void
+ck_hs_map_signal(struct ck_hs_map *map, unsigned long h)
+{
+
+ h &= CK_HS_G_MASK;
+ ck_pr_store_uint(&map->generation[h],
+ map->generation[h] + 1);
+ ck_pr_fence_store();
+ return;
+}
+
+void
+ck_hs_iterator_init(struct ck_hs_iterator *iterator)
+{
+
+ iterator->cursor = NULL;
+ iterator->offset = 0;
+ return;
+}
+
+bool
+ck_hs_next(struct ck_hs *hs, struct ck_hs_iterator *i, void **key)
+{
+ struct ck_hs_map *map = hs->map;
+ void *value;
+
+ if (i->offset >= map->capacity)
+ return false;
+
+ do {
+ value = CK_CC_DECONST_PTR(map->entries[i->offset]);
+ if (value != CK_HS_EMPTY && value != CK_HS_TOMBSTONE) {
+#ifdef CK_HS_PP
+ if (hs->mode & CK_HS_MODE_OBJECT)
+ value = CK_HS_VMA(value);
+#endif
+ i->offset++;
+ *key = value;
+ return true;
+ }
+ } while (++i->offset < map->capacity);
+
+ return false;
+}
+
+void
+ck_hs_stat(struct ck_hs *hs, struct ck_hs_stat *st)
+{
+ struct ck_hs_map *map = hs->map;
+
+ st->n_entries = map->n_entries;
+ st->tombstones = map->tombstones;
+ st->probe_maximum = map->probe_maximum;
+ return;
+}
+
+unsigned long
+ck_hs_count(struct ck_hs *hs)
+{
+
+ return hs->map->n_entries;
+}
+
+static void
+ck_hs_map_destroy(struct ck_malloc *m, struct ck_hs_map *map, bool defer)
+{
+
+ m->free(map, map->size, defer);
+ return;
+}
+
+void
+ck_hs_destroy(struct ck_hs *hs)
+{
+
+ ck_hs_map_destroy(hs->m, hs->map, false);
+ return;
+}
+
+static struct ck_hs_map *
+ck_hs_map_create(struct ck_hs *hs, unsigned long entries)
+{
+ struct ck_hs_map *map;
+ unsigned long size, n_entries, prefix, limit;
+
+ n_entries = ck_internal_power_2(entries);
+ if (n_entries < CK_HS_PROBE_L1)
+ n_entries = CK_HS_PROBE_L1;
+
+ size = sizeof(struct ck_hs_map) + (sizeof(void *) * n_entries + CK_MD_CACHELINE - 1);
+
+ if (hs->mode & CK_HS_MODE_DELETE) {
+ prefix = sizeof(CK_HS_WORD) * n_entries;
+ size += prefix;
+ } else {
+ prefix = 0;
+ }
+
+ map = hs->m->malloc(size);
+ if (map == NULL)
+ return NULL;
+
+ map->size = size;
+
+ /* We should probably use a more intelligent heuristic for default probe length. */
+ limit = ck_internal_max(n_entries >> (CK_HS_PROBE_L1_SHIFT + 2), CK_HS_PROBE_L1_DEFAULT);
+ if (limit > UINT_MAX)
+ limit = UINT_MAX;
+
+ map->probe_limit = (unsigned int)limit;
+ map->probe_maximum = 0;
+ map->capacity = n_entries;
+ map->step = ck_internal_bsf(n_entries);
+ map->mask = n_entries - 1;
+ map->n_entries = 0;
+
+ /* Align map allocation to cache line. */
+ map->entries = (void *)(((uintptr_t)&map[1] + prefix +
+ CK_MD_CACHELINE - 1) & ~(CK_MD_CACHELINE - 1));
+
+ memset(map->entries, 0, sizeof(void *) * n_entries);
+ memset(map->generation, 0, sizeof map->generation);
+
+ if (hs->mode & CK_HS_MODE_DELETE) {
+ map->probe_bound = (CK_HS_WORD *)&map[1];
+ memset(map->probe_bound, 0, prefix);
+ } else {
+ map->probe_bound = NULL;
+ }
+
+ /* Commit entries purge with respect to map publication. */
+ ck_pr_fence_store();
+ return map;
+}
+
+bool
+ck_hs_reset_size(struct ck_hs *hs, unsigned long capacity)
+{
+ struct ck_hs_map *map, *previous;
+
+ previous = hs->map;
+ map = ck_hs_map_create(hs, capacity);
+ if (map == NULL)
+ return false;
+
+ ck_pr_store_ptr(&hs->map, map);
+ ck_hs_map_destroy(hs->m, previous, true);
+ return true;
+}
+
+bool
+ck_hs_reset(struct ck_hs *hs)
+{
+ struct ck_hs_map *previous;
+
+ previous = hs->map;
+ return ck_hs_reset_size(hs, previous->capacity);
+}
+
+static inline unsigned long
+ck_hs_map_probe_next(struct ck_hs_map *map,
+ unsigned long offset,
+ unsigned long h,
+ unsigned long level,
+ unsigned long probes)
+{
+ unsigned long r, stride;
+
+ r = (h >> map->step) >> level;
+ stride = (r & ~CK_HS_PROBE_L1_MASK) << 1 | (r & CK_HS_PROBE_L1_MASK);
+
+ return (offset + (probes >> CK_HS_PROBE_L1_SHIFT) +
+ (stride | CK_HS_PROBE_L1)) & map->mask;
+}
+
+static inline void
+ck_hs_map_bound_set(struct ck_hs_map *m,
+ unsigned long h,
+ unsigned long n_probes)
+{
+ unsigned long offset = h & m->mask;
+
+ if (n_probes > m->probe_maximum)
+ ck_pr_store_uint(&m->probe_maximum, n_probes);
+
+ if (m->probe_bound != NULL && m->probe_bound[offset] < n_probes) {
+ if (n_probes > CK_HS_WORD_MAX)
+ n_probes = CK_HS_WORD_MAX;
+
+ CK_HS_STORE(&m->probe_bound[offset], n_probes);
+ ck_pr_fence_store();
+ }
+
+ return;
+}
+
+static inline unsigned int
+ck_hs_map_bound_get(struct ck_hs_map *m, unsigned long h)
+{
+ unsigned long offset = h & m->mask;
+ unsigned int r = CK_HS_WORD_MAX;
+
+ if (m->probe_bound != NULL) {
+ r = CK_HS_LOAD(&m->probe_bound[offset]);
+ if (r == CK_HS_WORD_MAX)
+ r = ck_pr_load_uint(&m->probe_maximum);
+ } else {
+ r = ck_pr_load_uint(&m->probe_maximum);
+ }
+
+ return r;
+}
+
+bool
+ck_hs_grow(struct ck_hs *hs,
+ unsigned long capacity)
+{
+ struct ck_hs_map *map, *update;
+ unsigned long k, i, j, offset, probes;
+ const void *previous, **bucket;
+
+restart:
+ map = hs->map;
+ if (map->capacity > capacity)
+ return false;
+
+ update = ck_hs_map_create(hs, capacity);
+ if (update == NULL)
+ return false;
+
+ for (k = 0; k < map->capacity; k++) {
+ unsigned long h;
+
+ previous = map->entries[k];
+ if (previous == CK_HS_EMPTY || previous == CK_HS_TOMBSTONE)
+ continue;
+
+#ifdef CK_HS_PP
+ if (hs->mode & CK_HS_MODE_OBJECT)
+ previous = CK_HS_VMA(previous);
+#endif
+
+ h = hs->hf(previous, hs->seed);
+ offset = h & update->mask;
+ i = probes = 0;
+
+ for (;;) {
+ bucket = (const void **)((uintptr_t)&update->entries[offset] & ~(CK_MD_CACHELINE - 1));
+
+ for (j = 0; j < CK_HS_PROBE_L1; j++) {
+ const void **cursor = bucket + ((j + offset) & (CK_HS_PROBE_L1 - 1));
+
+ if (probes++ == update->probe_limit)
+ break;
+
+ if (CK_CC_LIKELY(*cursor == CK_HS_EMPTY)) {
+ *cursor = map->entries[k];
+ update->n_entries++;
+
+ ck_hs_map_bound_set(update, h, probes);
+ break;
+ }
+ }
+
+ if (j < CK_HS_PROBE_L1)
+ break;
+
+ offset = ck_hs_map_probe_next(update, offset, h, i++, probes);
+ }
+
+ if (probes > update->probe_limit) {
+ /*
+ * We have hit the probe limit, map needs to be even larger.
+ */
+ ck_hs_map_destroy(hs->m, update, false);
+ capacity <<= 1;
+ goto restart;
+ }
+ }
+
+ ck_pr_fence_store();
+ ck_pr_store_ptr(&hs->map, update);
+ ck_hs_map_destroy(hs->m, map, true);
+ return true;
+}
+
+static void
+ck_hs_map_postinsert(struct ck_hs *hs, struct ck_hs_map *map)
+{
+
+ map->n_entries++;
+ if ((map->n_entries << 1) > map->capacity)
+ ck_hs_grow(hs, map->capacity << 1);
+
+ return;
+}
+
+bool
+ck_hs_rebuild(struct ck_hs *hs)
+{
+
+ return ck_hs_grow(hs, hs->map->capacity);
+}
+
+static const void **
+ck_hs_map_probe(struct ck_hs *hs,
+ struct ck_hs_map *map,
+ unsigned long *n_probes,
+ const void ***priority,
+ unsigned long h,
+ const void *key,
+ const void **object,
+ unsigned long probe_limit,
+ enum ck_hs_probe_behavior behavior)
+{
+ const void **bucket, **cursor, *k, *compare;
+ const void **pr = NULL;
+ unsigned long offset, j, i, probes, opl;
+
+#ifdef CK_HS_PP
+ /* If we are storing object pointers, then we may leverage pointer packing. */
+ unsigned long hv = 0;
+
+ if (hs->mode & CK_HS_MODE_OBJECT) {
+ hv = (h >> 25) & CK_HS_KEY_MASK;
+ compare = CK_HS_VMA(key);
+ } else {
+ compare = key;
+ }
+#else
+ compare = key;
+#endif
+
+ offset = h & map->mask;
+ *object = NULL;
+ i = probes = 0;
+
+ opl = probe_limit;
+ if (behavior == CK_HS_PROBE_INSERT)
+ probe_limit = ck_hs_map_bound_get(map, h);
+
+ for (;;) {
+ bucket = (const void **)((uintptr_t)&map->entries[offset] & ~(CK_MD_CACHELINE - 1));
+
+ for (j = 0; j < CK_HS_PROBE_L1; j++) {
+ cursor = bucket + ((j + offset) & (CK_HS_PROBE_L1 - 1));
+
+ if (probes++ == probe_limit) {
+ if (probe_limit == opl || pr != NULL) {
+ k = CK_HS_EMPTY;
+ goto leave;
+ }
+
+ /*
+ * If no eligible slot has been found yet, continue probe
+ * sequence with original probe limit.
+ */
+ probe_limit = opl;
+ }
+
+ k = ck_pr_load_ptr(cursor);
+ if (k == CK_HS_EMPTY)
+ goto leave;
+
+ if (k == CK_HS_TOMBSTONE) {
+ if (pr == NULL) {
+ pr = cursor;
+ *n_probes = probes;
+
+ if (behavior == CK_HS_PROBE_TOMBSTONE) {
+ k = CK_HS_EMPTY;
+ goto leave;
+ }
+ }
+
+ continue;
+ }
+
+#ifdef CK_HS_PP
+ if (hs->mode & CK_HS_MODE_OBJECT) {
+ if (((uintptr_t)k >> CK_MD_VMA_BITS) != hv)
+ continue;
+
+ k = CK_HS_VMA(k);
+ }
+#endif
+
+ if (k == compare)
+ goto leave;
+
+ if (hs->compare == NULL)
+ continue;
+
+ if (hs->compare(k, key) == true)
+ goto leave;
+ }
+
+ offset = ck_hs_map_probe_next(map, offset, h, i++, probes);
+ }
+
+leave:
+ if (probes > probe_limit) {
+ cursor = NULL;
+ } else {
+ *object = k;
+ }
+
+ if (pr == NULL)
+ *n_probes = probes;
+
+ *priority = pr;
+ return cursor;
+}
+
+static inline const void *
+ck_hs_marshal(unsigned int mode, const void *key, unsigned long h)
+{
+#ifdef CK_HS_PP
+ const void *insert;
+
+ if (mode & CK_HS_MODE_OBJECT) {
+ insert = (void *)((uintptr_t)CK_HS_VMA(key) |
+ ((h >> 25) << CK_MD_VMA_BITS));
+ } else {
+ insert = key;
+ }
+
+ return insert;
+#else
+ (void)mode;
+ (void)h;
+
+ return key;
+#endif
+}
+
+bool
+ck_hs_gc(struct ck_hs *hs, unsigned long cycles, unsigned long seed)
+{
+ unsigned long size = 0;
+ unsigned long i;
+ struct ck_hs_map *map = hs->map;
+ unsigned int maximum;
+ CK_HS_WORD *bounds = NULL;
+
+ if (map->n_entries == 0) {
+ ck_pr_store_uint(&map->probe_maximum, 0);
+ if (map->probe_bound != NULL)
+ memset(map->probe_bound, 0, sizeof(CK_HS_WORD) * map->capacity);
+
+ return true;
+ }
+
+ if (cycles == 0) {
+ maximum = 0;
+
+ if (map->probe_bound != NULL) {
+ size = sizeof(CK_HS_WORD) * map->capacity;
+ bounds = hs->m->malloc(size);
+ if (bounds == NULL)
+ return false;
+
+ memset(bounds, 0, size);
+ }
+ } else {
+ maximum = map->probe_maximum;
+ }
+
+ for (i = 0; i < map->capacity; i++) {
+ const void **first, *object, **slot, *entry;
+ unsigned long n_probes, offset, h;
+
+ entry = map->entries[(i + seed) & map->mask];
+ if (entry == CK_HS_EMPTY || entry == CK_HS_TOMBSTONE)
+ continue;
+
+#ifdef CK_HS_PP
+ if (hs->mode & CK_HS_MODE_OBJECT)
+ entry = CK_HS_VMA(entry);
+#endif
+
+ h = hs->hf(entry, hs->seed);
+ offset = h & map->mask;
+
+ slot = ck_hs_map_probe(hs, map, &n_probes, &first, h, entry, &object,
+ ck_hs_map_bound_get(map, h), CK_HS_PROBE);
+
+ if (first != NULL) {
+ const void *insert = ck_hs_marshal(hs->mode, entry, h);
+
+ ck_pr_store_ptr(first, insert);
+ ck_hs_map_signal(map, h);
+ ck_pr_store_ptr(slot, CK_HS_TOMBSTONE);
+ }
+
+ if (cycles == 0) {
+ if (n_probes > maximum)
+ maximum = n_probes;
+
+ if (n_probes > CK_HS_WORD_MAX)
+ n_probes = CK_HS_WORD_MAX;
+
+ if (bounds != NULL && n_probes > bounds[offset])
+ bounds[offset] = n_probes;
+ } else if (--cycles == 0)
+ break;
+ }
+
+ /*
+ * The following only apply to garbage collection involving
+ * a full scan of all entries.
+ */
+ if (maximum != map->probe_maximum)
+ ck_pr_store_uint(&map->probe_maximum, maximum);
+
+ if (bounds != NULL) {
+ for (i = 0; i < map->capacity; i++)
+ CK_HS_STORE(&map->probe_bound[i], bounds[i]);
+
+ hs->m->free(bounds, size, false);
+ }
+
+ return true;
+}
+
+bool
+ck_hs_fas(struct ck_hs *hs,
+ unsigned long h,
+ const void *key,
+ void **previous)
+{
+ const void **slot, **first, *object, *insert;
+ struct ck_hs_map *map = hs->map;
+ unsigned long n_probes;
+
+ *previous = NULL;
+ slot = ck_hs_map_probe(hs, map, &n_probes, &first, h, key, &object,
+ ck_hs_map_bound_get(map, h), CK_HS_PROBE);
+
+ /* Replacement semantics presume existence. */
+ if (object == NULL)
+ return false;
+
+ insert = ck_hs_marshal(hs->mode, key, h);
+
+ if (first != NULL) {
+ ck_pr_store_ptr(first, insert);
+ ck_hs_map_signal(map, h);
+ ck_pr_store_ptr(slot, CK_HS_TOMBSTONE);
+ } else {
+ ck_pr_store_ptr(slot, insert);
+ }
+
+ *previous = CK_CC_DECONST_PTR(object);
+ return true;
+}
+
+/*
+ * An apply function takes two arguments. The first argument is a pointer to a
+ * pre-existing object. The second argument is a pointer to the fifth argument
+ * passed to ck_hs_apply. If a non-NULL pointer is passed to the first argument
+ * and the return value of the apply function is NULL, then the pre-existing
+ * value is deleted. If the return pointer is the same as the one passed to the
+ * apply function then no changes are made to the hash table. If the first
+ * argument is non-NULL and the return pointer is different than that passed to
+ * the apply function, then the pre-existing value is replaced. For
+ * replacement, it is required that the value itself is identical to the
+ * previous value.
+ */
+bool
+ck_hs_apply(struct ck_hs *hs,
+ unsigned long h,
+ const void *key,
+ ck_hs_apply_fn_t *fn,
+ void *cl)
+{
+ const void **slot, **first, *object, *delta, *insert;
+ unsigned long n_probes;
+ struct ck_hs_map *map;
+
+restart:
+ map = hs->map;
+
+ slot = ck_hs_map_probe(hs, map, &n_probes, &first, h, key, &object, map->probe_limit, CK_HS_PROBE_INSERT);
+ if (slot == NULL && first == NULL) {
+ if (ck_hs_grow(hs, map->capacity << 1) == false)
+ return false;
+
+ goto restart;
+ }
+
+ delta = fn(CK_CC_DECONST_PTR(object), cl);
+ if (delta == NULL) {
+ /*
+ * The apply function has requested deletion. If the object doesn't exist,
+ * then exit early.
+ */
+ if (CK_CC_UNLIKELY(object == NULL))
+ return true;
+
+ /* Otherwise, mark slot as deleted. */
+ ck_pr_store_ptr(slot, CK_HS_TOMBSTONE);
+ map->n_entries--;
+ map->tombstones++;
+ return true;
+ }
+
+ /* The apply function has not requested hash set modification so exit early. */
+ if (delta == object)
+ return true;
+
+ /* A modification or insertion has been requested. */
+ ck_hs_map_bound_set(map, h, n_probes);
+
+ insert = ck_hs_marshal(hs->mode, delta, h);
+ if (first != NULL) {
+ /*
+ * This follows the same semantics as ck_hs_set, please refer to that
+ * function for documentation.
+ */
+ ck_pr_store_ptr(first, insert);
+
+ if (object != NULL) {
+ ck_hs_map_signal(map, h);
+ ck_pr_store_ptr(slot, CK_HS_TOMBSTONE);
+ }
+ } else {
+ /*
+ * If we are storing into same slot, then atomic store is sufficient
+ * for replacement.
+ */
+ ck_pr_store_ptr(slot, insert);
+ }
+
+ if (object == NULL)
+ ck_hs_map_postinsert(hs, map);
+
+ return true;
+}
+
+bool
+ck_hs_set(struct ck_hs *hs,
+ unsigned long h,
+ const void *key,
+ void **previous)
+{
+ const void **slot, **first, *object, *insert;
+ unsigned long n_probes;
+ struct ck_hs_map *map;
+
+ *previous = NULL;
+
+restart:
+ map = hs->map;
+
+ slot = ck_hs_map_probe(hs, map, &n_probes, &first, h, key, &object, map->probe_limit, CK_HS_PROBE_INSERT);
+ if (slot == NULL && first == NULL) {
+ if (ck_hs_grow(hs, map->capacity << 1) == false)
+ return false;
+
+ goto restart;
+ }
+
+ ck_hs_map_bound_set(map, h, n_probes);
+ insert = ck_hs_marshal(hs->mode, key, h);
+
+ if (first != NULL) {
+ /* If an earlier bucket was found, then store entry there. */
+ ck_pr_store_ptr(first, insert);
+
+ /*
+ * If a duplicate key was found, then delete it after
+ * signaling concurrent probes to restart. Optionally,
+ * it is possible to install tombstone after grace
+ * period if we can guarantee earlier position of
+ * duplicate key.
+ */
+ if (object != NULL) {
+ ck_hs_map_signal(map, h);
+ ck_pr_store_ptr(slot, CK_HS_TOMBSTONE);
+ }
+ } else {
+ /*
+ * If we are storing into same slot, then atomic store is sufficient
+ * for replacement.
+ */
+ ck_pr_store_ptr(slot, insert);
+ }
+
+ if (object == NULL)
+ ck_hs_map_postinsert(hs, map);
+
+ *previous = CK_CC_DECONST_PTR(object);
+ return true;
+}
+
+CK_CC_INLINE static bool
+ck_hs_put_internal(struct ck_hs *hs,
+ unsigned long h,
+ const void *key,
+ enum ck_hs_probe_behavior behavior)
+{
+ const void **slot, **first, *object, *insert;
+ unsigned long n_probes;
+ struct ck_hs_map *map;
+
+restart:
+ map = hs->map;
+
+ slot = ck_hs_map_probe(hs, map, &n_probes, &first, h, key, &object,
+ map->probe_limit, behavior);
+
+ if (slot == NULL && first == NULL) {
+ if (ck_hs_grow(hs, map->capacity << 1) == false)
+ return false;
+
+ goto restart;
+ }
+
+ /* Fail operation if a match was found. */
+ if (object != NULL)
+ return false;
+
+ ck_hs_map_bound_set(map, h, n_probes);
+ insert = ck_hs_marshal(hs->mode, key, h);
+
+ if (first != NULL) {
+ /* Insert key into first bucket in probe sequence. */
+ ck_pr_store_ptr(first, insert);
+ } else {
+ /* An empty slot was found. */
+ ck_pr_store_ptr(slot, insert);
+ }
+
+ ck_hs_map_postinsert(hs, map);
+ return true;
+}
+
+bool
+ck_hs_put(struct ck_hs *hs,
+ unsigned long h,
+ const void *key)
+{
+
+ return ck_hs_put_internal(hs, h, key, CK_HS_PROBE_INSERT);
+}
+
+bool
+ck_hs_put_unique(struct ck_hs *hs,
+ unsigned long h,
+ const void *key)
+{
+
+ return ck_hs_put_internal(hs, h, key, CK_HS_PROBE_TOMBSTONE);
+}
+
+void *
+ck_hs_get(struct ck_hs *hs,
+ unsigned long h,
+ const void *key)
+{
+ const void **first, *object;
+ struct ck_hs_map *map;
+ unsigned long n_probes;
+ unsigned int g, g_p, probe;
+ unsigned int *generation;
+
+ do {
+ map = ck_pr_load_ptr(&hs->map);
+ generation = &map->generation[h & CK_HS_G_MASK];
+ g = ck_pr_load_uint(generation);
+ probe = ck_hs_map_bound_get(map, h);
+ ck_pr_fence_load();
+
+ ck_hs_map_probe(hs, map, &n_probes, &first, h, key, &object, probe, CK_HS_PROBE);
+
+ ck_pr_fence_load();
+ g_p = ck_pr_load_uint(generation);
+ } while (g != g_p);
+
+ return CK_CC_DECONST_PTR(object);
+}
+
+void *
+ck_hs_remove(struct ck_hs *hs,
+ unsigned long h,
+ const void *key)
+{
+ const void **slot, **first, *object;
+ struct ck_hs_map *map = hs->map;
+ unsigned long n_probes;
+
+ slot = ck_hs_map_probe(hs, map, &n_probes, &first, h, key, &object,
+ ck_hs_map_bound_get(map, h), CK_HS_PROBE);
+ if (object == NULL)
+ return NULL;
+
+ ck_pr_store_ptr(slot, CK_HS_TOMBSTONE);
+ map->n_entries--;
+ map->tombstones++;
+ return CK_CC_DECONST_PTR(object);
+}
+
+bool
+ck_hs_move(struct ck_hs *hs,
+ struct ck_hs *source,
+ ck_hs_hash_cb_t *hf,
+ ck_hs_compare_cb_t *compare,
+ struct ck_malloc *m)
+{
+
+ if (m == NULL || m->malloc == NULL || m->free == NULL || hf == NULL)
+ return false;
+
+ hs->mode = source->mode;
+ hs->seed = source->seed;
+ hs->map = source->map;
+ hs->m = m;
+ hs->hf = hf;
+ hs->compare = compare;
+ return true;
+}
+
+bool
+ck_hs_init(struct ck_hs *hs,
+ unsigned int mode,
+ ck_hs_hash_cb_t *hf,
+ ck_hs_compare_cb_t *compare,
+ struct ck_malloc *m,
+ unsigned long n_entries,
+ unsigned long seed)
+{
+
+ if (m == NULL || m->malloc == NULL || m->free == NULL || hf == NULL)
+ return false;
+
+ hs->m = m;
+ hs->mode = mode;
+ hs->seed = seed;
+ hs->hf = hf;
+ hs->compare = compare;
+
+ hs->map = ck_hs_map_create(hs, n_entries);
+ return hs->map != NULL;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-19 10:08:43 +0000