Mercurial > hg > nginx
view src/event/ngx_event_posted.c @ 4135:d8e24515176e
Fix of cpu hog in event pipe.
If client closed connection in ngx_event_pipe_write_to_downstream(), buffers
in the "out" chain were lost. This caused cpu hog if all available buffers
were in the "out" chain. Fix is to call ngx_chain_update_chains() before
checking return code of output filter to avoid loosing buffers in the "out"
chain.
Note that this situation (all available buffers in the "out" chain) isn't
normal, it should be prevented by busy buffers limit. Though right now it
may happen with complex protocols like fastcgi. This should be addressed
separately.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Tue, 20 Sep 2011 09:55:27 +0000 |
parents | 9c2f3ed7a247 |
children | d620f497c50f |
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/* * Copyright (C) Igor Sysoev */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> ngx_thread_volatile ngx_event_t *ngx_posted_accept_events; ngx_thread_volatile ngx_event_t *ngx_posted_events; #if (NGX_THREADS) ngx_mutex_t *ngx_posted_events_mutex; #endif void ngx_event_process_posted(ngx_cycle_t *cycle, ngx_thread_volatile ngx_event_t **posted) { ngx_event_t *ev; for ( ;; ) { ev = (ngx_event_t *) *posted; ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "posted event %p", ev); if (ev == NULL) { return; } ngx_delete_posted_event(ev); ev->handler(ev); } } #if (NGX_THREADS) && !(NGX_WIN32) void ngx_wakeup_worker_thread(ngx_cycle_t *cycle) { ngx_int_t i; #if 0 ngx_uint_t busy; ngx_event_t *ev; busy = 1; if (ngx_mutex_lock(ngx_posted_events_mutex) == NGX_ERROR) { return; } for (ev = (ngx_event_t *) ngx_posted_events; ev; ev = ev->next) { if (*(ev->lock) == 0) { busy = 0; break; } } ngx_mutex_unlock(ngx_posted_events_mutex); if (busy) { return; } #endif for (i = 0; i < ngx_threads_n; i++) { if (ngx_threads[i].state == NGX_THREAD_FREE) { ngx_cond_signal(ngx_threads[i].cv); return; } } } ngx_int_t ngx_event_thread_process_posted(ngx_cycle_t *cycle) { ngx_event_t *ev; for ( ;; ) { ev = (ngx_event_t *) ngx_posted_events; for ( ;; ) { ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "posted event %p", ev); if (ev == NULL) { return NGX_OK; } if (ngx_trylock(ev->lock) == 0) { ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "posted event %p is busy", ev); ev = ev->next; continue; } if (ev->lock != ev->own_lock) { if (*(ev->own_lock)) { ngx_log_error(NGX_LOG_ALERT, cycle->log, 0, "the own lock of the posted event %p is busy", ev); ngx_unlock(ev->lock); ev = ev->next; continue; } *(ev->own_lock) = 1; } ngx_delete_posted_event(ev); ev->locked = 1; ev->ready |= ev->posted_ready; ev->timedout |= ev->posted_timedout; ev->pending_eof |= ev->posted_eof; #if (NGX_HAVE_KQUEUE) ev->kq_errno |= ev->posted_errno; #endif if (ev->posted_available) { ev->available = ev->posted_available; } ev->posted_ready = 0; ev->posted_timedout = 0; ev->posted_eof = 0; #if (NGX_HAVE_KQUEUE) ev->posted_errno = 0; #endif ev->posted_available = 0; ngx_mutex_unlock(ngx_posted_events_mutex); ev->handler(ev); ngx_mutex_lock(ngx_posted_events_mutex); if (ev->locked) { ngx_unlock(ev->lock); if (ev->lock != ev->own_lock) { ngx_unlock(ev->own_lock); } } ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "posted event %p is done", ev); break; } } } #else void ngx_wakeup_worker_thread(ngx_cycle_t *cycle) { } #endif