Mercurial > hg > nginx-quic
view src/event/ngx_event_timer.c @ 4569:1db899642518
Upstream: reject upstreams without normal servers.
Such upstreams cause CPU hog later in the code as number of peers isn't
expected to be 0. Currently this may happen either if there are only backup
servers defined in an upstream block, or if server with ipv6 address used
in an upstream block.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Mon, 02 Apr 2012 21:29:35 +0000 |
parents | d620f497c50f |
children | 876e6b0814a5 |
line wrap: on
line source
/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> #if (NGX_THREADS) ngx_mutex_t *ngx_event_timer_mutex; #endif ngx_thread_volatile ngx_rbtree_t ngx_event_timer_rbtree; static ngx_rbtree_node_t ngx_event_timer_sentinel; /* * the event timer rbtree may contain the duplicate keys, however, * it should not be a problem, because we use the rbtree to find * a minimum timer value only */ ngx_int_t ngx_event_timer_init(ngx_log_t *log) { ngx_rbtree_init(&ngx_event_timer_rbtree, &ngx_event_timer_sentinel, ngx_rbtree_insert_timer_value); #if (NGX_THREADS) if (ngx_event_timer_mutex) { ngx_event_timer_mutex->log = log; return NGX_OK; } ngx_event_timer_mutex = ngx_mutex_init(log, 0); if (ngx_event_timer_mutex == NULL) { return NGX_ERROR; } #endif return NGX_OK; } ngx_msec_t ngx_event_find_timer(void) { ngx_msec_int_t timer; ngx_rbtree_node_t *node, *root, *sentinel; if (ngx_event_timer_rbtree.root == &ngx_event_timer_sentinel) { return NGX_TIMER_INFINITE; } ngx_mutex_lock(ngx_event_timer_mutex); root = ngx_event_timer_rbtree.root; sentinel = ngx_event_timer_rbtree.sentinel; node = ngx_rbtree_min(root, sentinel); ngx_mutex_unlock(ngx_event_timer_mutex); timer = (ngx_msec_int_t) node->key - (ngx_msec_int_t) ngx_current_msec; return (ngx_msec_t) (timer > 0 ? timer : 0); } void ngx_event_expire_timers(void) { ngx_event_t *ev; ngx_rbtree_node_t *node, *root, *sentinel; sentinel = ngx_event_timer_rbtree.sentinel; for ( ;; ) { ngx_mutex_lock(ngx_event_timer_mutex); root = ngx_event_timer_rbtree.root; if (root == sentinel) { return; } node = ngx_rbtree_min(root, sentinel); /* node->key <= ngx_current_time */ if ((ngx_msec_int_t) node->key - (ngx_msec_int_t) ngx_current_msec <= 0) { ev = (ngx_event_t *) ((char *) node - offsetof(ngx_event_t, timer)); #if (NGX_THREADS) if (ngx_threaded && ngx_trylock(ev->lock) == 0) { /* * We cannot change the timer of the event that is being * handled by another thread. And we cannot easy walk * the rbtree to find next expired timer so we exit the loop. * However, it should be a rare case when the event that is * being handled has an expired timer. */ ngx_log_debug1(NGX_LOG_DEBUG_EVENT, ev->log, 0, "event %p is busy in expire timers", ev); break; } #endif ngx_log_debug2(NGX_LOG_DEBUG_EVENT, ev->log, 0, "event timer del: %d: %M", ngx_event_ident(ev->data), ev->timer.key); ngx_rbtree_delete(&ngx_event_timer_rbtree, &ev->timer); ngx_mutex_unlock(ngx_event_timer_mutex); #if (NGX_DEBUG) ev->timer.left = NULL; ev->timer.right = NULL; ev->timer.parent = NULL; #endif ev->timer_set = 0; #if (NGX_THREADS) if (ngx_threaded) { ev->posted_timedout = 1; ngx_post_event(ev, &ngx_posted_events); ngx_unlock(ev->lock); continue; } #endif ev->timedout = 1; ev->handler(ev); continue; } break; } ngx_mutex_unlock(ngx_event_timer_mutex); }