Mercurial > hg > nginx
view src/event/ngx_event_timer.h @ 6422:768e287a6f36
Fixed sendfile in threads (or with aio preload) and subrequests.
If sendfile in threads is used, it is possible that multiple
subrequests will trigger multiple ngx_linux_sendfile_thread() calls,
as operations are only serialized in output chain based on r->aio,
that is, on subrequest level.
This resulted in "task #N already active" alerts, in particular, when
running proxy_store.t with "aio threads; sendfile on;".
Fix is to tolerate duplicate calls, with an additional safety check
that the file is the same as previously used.
The same problem also affects "aio on; sendfile on;" on FreeBSD
(previously known as "aio sendfile;"), where aio->preload_handler()
could be called multiple times due to similar reasons, resulting in
"second aio post" alerts. Fix is the same as well.
It is also believed that similar problems can arise if a filter
calls the next body filter multiple times for some reason. These are
mostly theoretical though.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Thu, 03 Mar 2016 21:14:12 +0300 |
parents | 3efdd7788bb0 |
children | 3069dd358ba2 |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #ifndef _NGX_EVENT_TIMER_H_INCLUDED_ #define _NGX_EVENT_TIMER_H_INCLUDED_ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> #define NGX_TIMER_INFINITE (ngx_msec_t) -1 #define NGX_TIMER_LAZY_DELAY 300 ngx_int_t ngx_event_timer_init(ngx_log_t *log); ngx_msec_t ngx_event_find_timer(void); void ngx_event_expire_timers(void); void ngx_event_cancel_timers(void); extern ngx_rbtree_t ngx_event_timer_rbtree; static ngx_inline void ngx_event_del_timer(ngx_event_t *ev) { 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); #if (NGX_DEBUG) ev->timer.left = NULL; ev->timer.right = NULL; ev->timer.parent = NULL; #endif ev->timer_set = 0; } static ngx_inline void ngx_event_add_timer(ngx_event_t *ev, ngx_msec_t timer) { ngx_msec_t key; ngx_msec_int_t diff; key = ngx_current_msec + timer; if (ev->timer_set) { /* * Use a previous timer value if difference between it and a new * value is less than NGX_TIMER_LAZY_DELAY milliseconds: this allows * to minimize the rbtree operations for fast connections. */ diff = (ngx_msec_int_t) (key - ev->timer.key); if (ngx_abs(diff) < NGX_TIMER_LAZY_DELAY) { ngx_log_debug3(NGX_LOG_DEBUG_EVENT, ev->log, 0, "event timer: %d, old: %M, new: %M", ngx_event_ident(ev->data), ev->timer.key, key); return; } ngx_del_timer(ev); } ev->timer.key = key; ngx_log_debug3(NGX_LOG_DEBUG_EVENT, ev->log, 0, "event timer add: %d: %M:%M", ngx_event_ident(ev->data), timer, ev->timer.key); ngx_rbtree_insert(&ngx_event_timer_rbtree, &ev->timer); ev->timer_set = 1; } #endif /* _NGX_EVENT_TIMER_H_INCLUDED_ */