X-Git-Url: http://git.liburcu.org/?p=urcu.git;a=blobdiff_plain;f=rculfhash.c;h=fe8beedd7a9119d6b88e9a5e3fddec4267fd22a9;hp=79b8e86429b176d739b7777860d830db8cfe2c02;hb=920f8ef668b03c65ca414bd6d53db314da920d1f;hpb=4dd4a47355d9d870d482248786b4adf8b1317bfe diff --git a/rculfhash.c b/rculfhash.c index 79b8e86..fe8beed 100644 --- a/rculfhash.c +++ b/rculfhash.c @@ -139,7 +139,7 @@ #include #include -#include +#include "config.h" #include #include #include @@ -255,7 +255,7 @@ struct rcu_resize_work { }; struct partition_resize_work { - struct rcu_head head; + pthread_t thread_id; struct cds_lfht *ht; unsigned long i, start, len; void (*fct)(struct cds_lfht *ht, unsigned long i, @@ -446,24 +446,28 @@ unsigned int fls_ulong(unsigned long x) #endif } +/* + * Return the minimum order for which x <= (1UL << order). + * Return -1 if x is 0. + */ int get_count_order_u32(uint32_t x) { - int order; + if (!x) + return -1; - order = fls_u32(x) - 1; - if (x & (x - 1)) - order++; - return order; + return fls_u32(x - 1); } +/* + * Return the minimum order for which x <= (1UL << order). + * Return -1 if x is 0. + */ int get_count_order_ulong(unsigned long x) { - int order; + if (!x) + return -1; - order = fls_ulong(x) - 1; - if (x & (x - 1)) - order++; - return order; + return fls_ulong(x - 1); } #ifdef POISON_FREE @@ -608,7 +612,7 @@ void ht_count_del(struct cds_lfht *ht, unsigned long size) #else /* #if defined(HAVE_SCHED_GETCPU) && defined(HAVE_SYSCONF) */ -static const long nr_cpus_mask = -1; +static const long nr_cpus_mask = -2; static struct ht_items_count *alloc_per_cpu_items_count(void) @@ -1034,18 +1038,20 @@ void partition_resize_helper(struct cds_lfht *ht, unsigned long i, struct partition_resize_work *work; int thread, ret; unsigned long nr_threads; - pthread_t *thread_id; /* * Note: nr_cpus_mask + 1 is always power of 2. * We spawn just the number of threads we need to satisfy the minimum * partition size, up to the number of CPUs in the system. */ - nr_threads = min(nr_cpus_mask + 1, - len >> MIN_PARTITION_PER_THREAD_ORDER); + if (nr_cpus_mask > 0) { + nr_threads = min(nr_cpus_mask + 1, + len >> MIN_PARTITION_PER_THREAD_ORDER); + } else { + nr_threads = 1; + } partition_len = len >> get_count_order_ulong(nr_threads); work = calloc(nr_threads, sizeof(*work)); - thread_id = calloc(nr_threads, sizeof(*thread_id)); assert(work); for (thread = 0; thread < nr_threads; thread++) { work[thread].ht = ht; @@ -1053,16 +1059,15 @@ void partition_resize_helper(struct cds_lfht *ht, unsigned long i, work[thread].len = partition_len; work[thread].start = thread * partition_len; work[thread].fct = fct; - ret = pthread_create(&thread_id[thread], ht->resize_attr, + ret = pthread_create(&(work[thread].thread_id), ht->resize_attr, partition_resize_thread, &work[thread]); assert(!ret); } for (thread = 0; thread < nr_threads; thread++) { - ret = pthread_join(thread_id[thread], NULL); + ret = pthread_join(work[thread].thread_id, NULL); assert(!ret); } free(work); - free(thread_id); } /* @@ -1093,8 +1098,6 @@ void init_table_populate_partition(struct cds_lfht *ht, unsigned long i, bit_reverse_ulong(!i ? 0 : (1UL << (i - 1)) + j); (void) _cds_lfht_add(ht, !i ? 0 : (1UL << (i - 1)), new_node, ADD_DEFAULT, 1); - if (CMM_LOAD_SHARED(ht->in_progress_destroy)) - break; } ht->cds_lfht_rcu_read_unlock(); } @@ -1196,8 +1199,6 @@ void remove_table_partition(struct cds_lfht *ht, unsigned long i, bit_reverse_ulong(!i ? 0 : (1UL << (i - 1)) + j); (void) _cds_lfht_del(ht, !i ? 0 : (1UL << (i - 1)), fini_node, 1); - if (CMM_LOAD_SHARED(ht->in_progress_destroy)) - break; } ht->cds_lfht_rcu_read_unlock(); } @@ -1355,7 +1356,7 @@ void cds_lfht_lookup(struct cds_lfht *ht, void *key, size_t key_len, iter->next = next; } -void cds_lfht_next(struct cds_lfht *ht, struct cds_lfht_iter *iter) +void cds_lfht_next_duplicate(struct cds_lfht *ht, struct cds_lfht_iter *iter) { struct cds_lfht_node *node, *next; unsigned long reverse_hash; @@ -1391,6 +1392,41 @@ void cds_lfht_next(struct cds_lfht *ht, struct cds_lfht_iter *iter) iter->next = next; } +void cds_lfht_next(struct cds_lfht *ht, struct cds_lfht_iter *iter) +{ + struct cds_lfht_node *node, *next; + + node = clear_flag(iter->next); + for (;;) { + if (unlikely(is_end(node))) { + node = next = NULL; + break; + } + next = rcu_dereference(node->p.next); + if (likely(!is_removed(next)) + && !is_dummy(next)) { + break; + } + node = clear_flag(next); + } + assert(!node || !is_dummy(rcu_dereference(node->p.next))); + iter->node = node; + iter->next = next; +} + +void cds_lfht_first(struct cds_lfht *ht, struct cds_lfht_iter *iter) +{ + struct _cds_lfht_node *lookup; + + /* + * Get next after first dummy node. The first dummy node is the + * first node of the linked list. + */ + lookup = &ht->t.tbl[0]->nodes[0]; + iter->next = lookup->next; + cds_lfht_next(ht, iter); +} + void cds_lfht_add(struct cds_lfht *ht, struct cds_lfht_node *node) { unsigned long hash, size; @@ -1503,7 +1539,8 @@ int cds_lfht_destroy(struct cds_lfht *ht, pthread_attr_t **attr) int ret; /* Wait for in-flight resize operations to complete */ - CMM_STORE_SHARED(ht->in_progress_destroy, 1); + _CMM_STORE_SHARED(ht->in_progress_destroy, 1); + cmm_smp_mb(); /* Store destroy before load resize */ while (uatomic_read(&ht->in_progress_resize)) poll(NULL, 0, 100); /* wait for 100ms */ ret = cds_lfht_delete_dummy(ht); @@ -1576,8 +1613,8 @@ void _do_cds_lfht_grow(struct cds_lfht *ht, old_order = get_count_order_ulong(old_size) + 1; new_order = get_count_order_ulong(new_size) + 1; - printf("resize from %lu (order %lu) to %lu (order %lu) buckets\n", - old_size, old_order, new_size, new_order); + dbg_printf("resize from %lu (order %lu) to %lu (order %lu) buckets\n", + old_size, old_order, new_size, new_order); assert(new_size > old_size); init_table(ht, old_order, new_order - old_order); } @@ -1592,8 +1629,8 @@ void _do_cds_lfht_shrink(struct cds_lfht *ht, new_size = max(new_size, MIN_TABLE_SIZE); old_order = get_count_order_ulong(old_size) + 1; new_order = get_count_order_ulong(new_size) + 1; - printf("resize from %lu (order %lu) to %lu (order %lu) buckets\n", - old_size, old_order, new_size, new_order); + dbg_printf("resize from %lu (order %lu) to %lu (order %lu) buckets\n", + old_size, old_order, new_size, new_order); assert(new_size < old_size); /* Remove and unlink all dummy nodes to remove. */ @@ -1611,6 +1648,9 @@ void _do_cds_lfht_resize(struct cds_lfht *ht) * Resize table, re-do if the target size has changed under us. */ do { + assert(uatomic_read(&ht->in_progress_resize)); + if (CMM_LOAD_SHARED(ht->in_progress_destroy)) + break; ht->t.resize_initiated = 1; old_size = ht->t.size; new_size = CMM_LOAD_SHARED(ht->t.resize_target); @@ -1679,7 +1719,11 @@ void cds_lfht_resize_lazy(struct cds_lfht *ht, unsigned long size, int growth) cmm_smp_mb(); if (!CMM_LOAD_SHARED(ht->t.resize_initiated) && size < target_size) { uatomic_inc(&ht->in_progress_resize); - cmm_smp_mb(); /* increment resize count before calling it */ + cmm_smp_mb(); /* increment resize count before load destroy */ + if (CMM_LOAD_SHARED(ht->in_progress_destroy)) { + uatomic_dec(&ht->in_progress_resize); + return; + } work = malloc(sizeof(*work)); work->ht = ht; ht->cds_lfht_call_rcu(&work->head, do_resize_cb); @@ -1702,7 +1746,11 @@ void cds_lfht_resize_lazy_count(struct cds_lfht *ht, unsigned long size, cmm_smp_mb(); if (!CMM_LOAD_SHARED(ht->t.resize_initiated)) { uatomic_inc(&ht->in_progress_resize); - cmm_smp_mb(); /* increment resize count before calling it */ + cmm_smp_mb(); /* increment resize count before load destroy */ + if (CMM_LOAD_SHARED(ht->in_progress_destroy)) { + uatomic_dec(&ht->in_progress_resize); + return; + } work = malloc(sizeof(*work)); work->ht = ht; ht->cds_lfht_call_rcu(&work->head, do_resize_cb);