diff options
Diffstat (limited to 'src/nxt_cache.c')
| -rw-r--r-- | src/nxt_cache.c | 642 |
1 files changed, 0 insertions, 642 deletions
diff --git a/src/nxt_cache.c b/src/nxt_cache.c deleted file mode 100644 index e81d63dc..00000000 --- a/src/nxt_cache.c +++ /dev/null @@ -1,642 +0,0 @@ - -/* - * Copyright (C) Igor Sysoev - * Copyright (C) NGINX, Inc. - */ - -#include <nxt_main.h> - - -/* A cache time resolution is 10ms. */ -#define nxt_cache_time(thr) \ - (uint64_t) (nxt_thread_time(thr) * 100) - - -static nxt_int_t nxt_cache_lvlhsh_test(nxt_lvlhsh_query_t *lhq, void *data); -static nxt_work_handler_t nxt_cache_query_locked(nxt_cache_t *cache, - nxt_cache_query_t *q, nxt_lvlhsh_query_t *lhq); -static nxt_work_handler_t nxt_cache_node_hold(nxt_cache_t *cache, - nxt_cache_query_t *q, nxt_lvlhsh_query_t *lhq); -static nxt_work_handler_t nxt_cache_node_test(nxt_cache_t *cache, - nxt_cache_query_t *q); - -static void nxt_cache_wait_handler(nxt_thread_t *thr, void *obj, void *data); -static void nxt_cache_timeout_handler(nxt_thread_t *thr, void *obj, void *data); -static void nxt_cache_wake_handler(nxt_thread_t *thr, void *obj, void *data); -static ssize_t nxt_cache_release_locked(nxt_cache_t *cache, - nxt_cache_query_t *q, u_char *buf, size_t size); - -static nxt_cache_node_t *nxt_cache_node_alloc(nxt_cache_t *cache); -static void nxt_cache_node_free(nxt_cache_t *cache, nxt_cache_node_t *node, - nxt_bool_t fast); -static nxt_cache_query_wait_t *nxt_cache_query_wait_alloc(nxt_cache_t *cache, - nxt_bool_t *slow); -static void nxt_cache_query_wait_free(nxt_cache_t *cache, - nxt_cache_query_wait_t *qw); - - -/* STUB */ -nxt_int_t nxt_cache_shm_create(nxt_mem_zone_t *pool); -static void *nxt_cache_shm_alloc(void *data, size_t size, nxt_uint_t nalloc); -/**/ - - -nxt_int_t -nxt_cache_shm_create(nxt_mem_zone_t *mz) -{ - nxt_cache_t *cache; - - static const nxt_lvlhsh_proto_t proto nxt_aligned(64) = { - NXT_LVLHSH_LARGE_SLAB, - 0, - nxt_cache_lvlhsh_test, - (nxt_lvlhsh_alloc_t) nxt_cache_shm_alloc, - (nxt_lvlhsh_free_t) nxt_mem_zone_free, - }; - - cache = nxt_mem_zone_zalloc(mz, sizeof(nxt_cache_t)); - - if (cache == NULL) { - return NXT_ERROR; - } - - cache->proto = &proto; - cache->pool = mz; - - cache->start_time = nxt_cache_time(nxt_thread()); - - return NXT_OK; -} - - -static void * -nxt_cache_shm_alloc(void *data, size_t size, nxt_uint_t nalloc) -{ - return nxt_mem_zone_align(data, size, size); -} - - -void -nxt_cache_init(nxt_cache_t *cache) -{ - static const nxt_lvlhsh_proto_t proto nxt_aligned(64) = { - NXT_LVLHSH_LARGE_MEMALIGN, - 0, - nxt_cache_lvlhsh_test, - nxt_lvlhsh_alloc, - nxt_lvlhsh_free, - }; - - cache->proto = &proto; - - cache->start_time = nxt_cache_time(nxt_thread()); -} - - -static nxt_int_t -nxt_cache_lvlhsh_test(nxt_lvlhsh_query_t *lhq, void *data) -{ - nxt_cache_node_t *node; - - node = data; - - if (nxt_str_eq(&lhq->key, node->key_data, node->key_len)) { - return NXT_OK; - } - - return NXT_DECLINED; -} - - -nxt_inline void -nxt_cache_lock(nxt_cache_t *cache) -{ - if (cache->shared) { - nxt_thread_spin_lock(&cache->lock); - } -} - - -nxt_inline void -nxt_cache_unlock(nxt_cache_t *cache) -{ - if (cache->shared) { - nxt_thread_spin_unlock(&cache->lock); - } -} - - -void -nxt_cache_query(nxt_cache_t *cache, nxt_cache_query_t *q) -{ - nxt_thread_t *thr; - nxt_lvlhsh_query_t lhq; - nxt_work_handler_t handler; - - thr = nxt_thread(); - - if (cache != NULL) { - lhq.key_hash = nxt_murmur_hash2(q->key_data, q->key_len); - lhq.replace = 0; - lhq.key.len = q->key_len; - lhq.key.data = q->key_data; - lhq.proto = cache->proto; - lhq.pool = cache->pool; - - q->now = nxt_cache_time(thr); - - nxt_cache_lock(cache); - - handler = nxt_cache_query_locked(cache, q, &lhq); - - nxt_cache_unlock(cache); - - } else { - handler = q->state->nocache_handler; - } - - handler(thr, q, NULL); -} - - -static nxt_work_handler_t -nxt_cache_query_locked(nxt_cache_t *cache, nxt_cache_query_t *q, - nxt_lvlhsh_query_t *lhq) -{ - nxt_int_t ret; - nxt_time_t expiry; - nxt_cache_node_t *node; - nxt_cache_query_state_t *state; - - if (q->hold) { - return nxt_cache_node_hold(cache, q, lhq); - } - - ret = nxt_lvlhsh_find(&cache->lvlhsh, lhq); - - state = q->state; - - if (ret != NXT_OK) { - /* NXT_DECLINED */ - return state->nocache_handler; - } - - node = lhq->value; - node->count++; - q->node = node; - - expiry = cache->start_time + node->expiry; - - if (q->now < expiry) { - return state->ready_handler; - } - - q->stale = 1; - - return state->stale_handler; -} - - -static nxt_work_handler_t -nxt_cache_node_hold(nxt_cache_t *cache, nxt_cache_query_t *q, - nxt_lvlhsh_query_t *lhq) -{ - nxt_int_t ret; - nxt_bool_t slow; - nxt_cache_node_t *node, *sentinel; - nxt_work_handler_t handler; - nxt_cache_query_wait_t *qw; - nxt_cache_query_state_t *state; - - state = q->state; - sentinel = nxt_cache_node_alloc(cache); - - if (nxt_slow_path(sentinel == NULL)) { - return state->error_handler; - } - - sentinel->key_data = q->key_data; - sentinel->key_len = q->key_len; - lhq->value = sentinel; - - /* - * Try to insert an empty sentinel node to hold updating - * process if there is no existent cache node in cache. - */ - ret = nxt_lvlhsh_insert(&cache->lvlhsh, lhq); - - if (ret == NXT_OK) { - /* The sentinel node was successully added. */ - - q->node = sentinel; - sentinel->updating = 1; - return state->update_handler; - } - - nxt_cache_node_free(cache, sentinel, 1); - - if (ret == NXT_ERROR) { - return state->error_handler; - } - - /* NXT_DECLINED: a cache node exists. */ - - node = lhq->value; - node->count++; - q->node = node; - - handler = nxt_cache_node_test(cache, q); - if (handler != NULL) { - return handler; - } - - /* Add the node to a wait queue. */ - - qw = nxt_cache_query_wait_alloc(cache, &slow); - if (nxt_slow_path(qw == NULL)) { - return state->error_handler; - } - - if (slow) { - /* The node state may have been changed during slow allocation. */ - - handler = nxt_cache_node_test(cache, q); - if (handler != NULL) { - nxt_cache_query_wait_free(cache, qw); - return handler; - } - } - - qw->query = q; - qw->next = node->waiting; - qw->busy = 0; - qw->deleted = 0; - qw->pid = nxt_pid; - qw->engine = nxt_thread_event_engine(); - qw->handler = nxt_cache_wake_handler; - qw->cache = cache; - - node->waiting = qw; - - return nxt_cache_wait_handler; -} - - -static nxt_work_handler_t -nxt_cache_node_test(nxt_cache_t *cache, nxt_cache_query_t *q) -{ - nxt_time_t expiry; - nxt_cache_node_t *node; - nxt_cache_query_state_t *state; - - q->stale = 0; - state = q->state; - node = q->node; - - expiry = cache->start_time + node->expiry; - - if (q->now < expiry) { - return state->ready_handler; - } - - /* - * A valid stale or empty sentinel cache node. - * The sentinel node can be only in updating state. - */ - - if (node->updating) { - - if (node->expiry != 0) { - /* A valid stale cache node. */ - - q->stale = 1; - - if (q->use_stale) { - return state->stale_handler; - } - } - - /* A sentinel node. */ - return NULL; - } - - /* A valid stale cache node is not being updated now. */ - - q->stale = 1; - - if (q->use_stale) { - - if (q->update_stale) { - node->updating = 1; - return state->update_stale_handler; - } - - return state->stale_handler; - } - - node->updating = 1; - return state->update_handler; -} - - -static void -nxt_cache_wait_handler(nxt_thread_t *thr, void *obj, void *data) -{ - nxt_event_timer_t *ev; - nxt_cache_query_t *cq; - - cq = obj; - - if (cq->timeout != 0) { - - ev = &cq->timer; - - if (ev->state == NXT_EVENT_TIMER_DISABLED) { - ev->handler = nxt_cache_timeout_handler; - nxt_event_timer_ident(ev, -1); - - nxt_event_timer_add(thr->engine, ev, cq->timeout); - } - } -} - - -static void -nxt_cache_timeout_handler(nxt_thread_t *thr, void *obj, void *data) -{ - nxt_cache_query_t *cq; - nxt_event_timer_t *ev; - - ev = obj; - - cq = nxt_event_timer_data(ev, nxt_cache_query_t, timer); - - cq->state->timeout_handler(thr, cq, NULL); -} - - -static void -nxt_cache_wake_handler(nxt_thread_t *thr, void *obj, void *data) -{ - nxt_cache_t *cache; - nxt_work_handler_t handler; - nxt_cache_query_t *q; - nxt_cache_query_wait_t *qw; - - qw = obj; - q = qw->query; - cache = qw->cache; - - nxt_cache_lock(cache); - - handler = nxt_cache_node_test(cache, q); - - if (handler != NULL) { - nxt_cache_query_wait_free(cache, qw); - - } else { - /* Wait again. */ - qw->next = q->node->waiting; - q->node->waiting = qw; - } - - nxt_cache_unlock(cache); - - handler(thr, q, NULL); -} - - -nxt_int_t -nxt_cache_update(nxt_cache_t *cache, nxt_cache_query_t *q) -{ - nxt_int_t ret; - nxt_cache_node_t *node; - nxt_lvlhsh_query_t lhq; - - node = q->node; - - node->accessed = nxt_cache_time(nxt_thread()) - cache->start_time; - - node->updating = 0; - node->count = 1; - - lhq.key_hash = nxt_murmur_hash2(node->key_data, node->key_len); - lhq.replace = 1; - lhq.key.len = node->key_len; - lhq.key.data = node->key_data; - lhq.value = node; - lhq.proto = cache->proto; - lhq.pool = cache->pool; - - nxt_cache_lock(cache); - - ret = nxt_lvlhsh_insert(&cache->lvlhsh, &lhq); - - if (nxt_fast_path(ret != NXT_OK)) { - - nxt_queue_insert_head(&cache->expiry_queue, &node->link); - - node = lhq.value; - - if (node != NULL) { - /* A replaced node. */ - - nxt_queue_remove(&node->link); - - if (node->count != 0) { - node->deleted = 1; - - } else { - // delete cache node - } - } - } - - nxt_cache_unlock(cache); - - return ret; -} - - -void -nxt_cache_release(nxt_cache_t *cache, nxt_cache_query_t *q) -{ - u_char *p, *data; - size_t size; - ssize_t ret; - nxt_thread_t *thr; - u_char buf[1024]; - - thr = nxt_thread(); - q->now = nxt_cache_time(thr); - - p = buf; - size = sizeof(buf); - - for ( ;; ) { - nxt_cache_lock(cache); - - ret = nxt_cache_release_locked(cache, q, p, size); - - nxt_cache_unlock(cache); - - if (ret == 0) { - return; - } - - size = nxt_abs(ret); - - data = nxt_malloc(size); - - if (data == NULL) { - /* TODO: retry */ - return; - } - - if (ret < 0) { - p = data; - continue; - } - - if (p != data) { - nxt_memcpy(data, p, size); - } - - nxt_thread_work_queue_add(thr, &thr->work_queue.main, - cache->delete_handler, data, NULL, thr->log); - } -} - - -static ssize_t -nxt_cache_release_locked(nxt_cache_t *cache, nxt_cache_query_t *q, - u_char *buf, size_t size) -{ - ssize_t ret; - nxt_cache_node_t *node; - - node = q->node; - node->count--; - - if (node->count != 0) { - return 0; - } - - if (!node->deleted) { - /* - * A cache node is locked whilst its count is non zero. - * To minimize number of operations the node's place in expiry - * queue can be updated only if the node is not currently used. - */ - node->accessed = q->now - cache->start_time; - - nxt_queue_remove(&node->link); - nxt_queue_insert_head(&cache->expiry_queue, &node->link); - - return 0; - } - - ret = 0; -#if 0 - - ret = cache->delete_copy(cache, node, buf, size); - - if (ret < 0) { - return ret; - } - -#endif - - nxt_cache_node_free(cache, node, 0); - - return ret; -} - - -static nxt_cache_node_t * -nxt_cache_node_alloc(nxt_cache_t *cache) -{ - nxt_queue_link_t *link; - nxt_cache_node_t *node; - - link = nxt_queue_first(&cache->free_nodes); - - if (nxt_fast_path(link != nxt_queue_tail(&cache->free_nodes))) { - cache->nfree_nodes--; - nxt_queue_remove(link); - - node = nxt_queue_link_data(link, nxt_cache_node_t, link); - nxt_memzero(node, sizeof(nxt_cache_node_t)); - - return node; - } - - nxt_cache_unlock(cache); - - node = cache->alloc(cache->data, sizeof(nxt_cache_node_t)); - - nxt_cache_lock(cache); - - return node; -} - - -static void -nxt_cache_node_free(nxt_cache_t *cache, nxt_cache_node_t *node, nxt_bool_t fast) -{ - if (fast || cache->nfree_nodes < 32) { - nxt_queue_insert_head(&cache->free_nodes, &node->link); - cache->nfree_nodes++; - return; - } - - nxt_cache_unlock(cache); - - cache->free(cache->data, node); - - nxt_cache_lock(cache); -} - - -static nxt_cache_query_wait_t * -nxt_cache_query_wait_alloc(nxt_cache_t *cache, nxt_bool_t *slow) -{ - nxt_cache_query_wait_t *qw; - - qw = cache->free_query_wait; - - if (nxt_fast_path(qw != NULL)) { - cache->free_query_wait = qw->next; - cache->nfree_query_wait--; - - *slow = 0; - return qw; - } - - nxt_cache_unlock(cache); - - qw = cache->alloc(cache->data, sizeof(nxt_cache_query_wait_t)); - *slow = 1; - - nxt_cache_lock(cache); - - return qw; -} - - -static void -nxt_cache_query_wait_free(nxt_cache_t *cache, nxt_cache_query_wait_t *qw) -{ - if (cache->nfree_query_wait < 32) { - qw->next = cache->free_query_wait; - cache->free_query_wait = qw; - cache->nfree_query_wait++; - return; - } - - nxt_cache_unlock(cache); - - cache->free(cache->data, qw); - - nxt_cache_lock(cache); -} |