Mercurial > hg > nginx
view src/event/ngx_event_timer.c @ 7631:b4dbf8b98f9a
Fixed premature background subrequest finalization.
When "aio" or "aio threads" is used while processing the response body of an
in-memory background subrequest, the subrequest could be finalized with an aio
operation still in progress. Upon aio completion either parent request is
woken or the old r->write_event_handler is called again. The latter may result
in request errors. In either case post_subrequest handler is never called with
the full response body, which is typically expected when using in-memory
subrequests.
Currently in nginx background subrequests are created by the upstream module
and the mirror module. The issue does not manifest itself with these
subrequests because they are header-only. But it can manifest itself with
third-party modules which create in-memory background subrequests.
author | Dmitry Volyntsev <xeioex@nginx.com> |
---|---|
date | Mon, 02 Mar 2020 20:07:36 +0300 |
parents | 03928f7f209b |
children | 0c5e84096d99 |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> 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); 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; } root = ngx_event_timer_rbtree.root; sentinel = ngx_event_timer_rbtree.sentinel; node = ngx_rbtree_min(root, sentinel); timer = (ngx_msec_int_t) (node->key - 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 ( ;; ) { root = ngx_event_timer_rbtree.root; if (root == sentinel) { return; } node = ngx_rbtree_min(root, sentinel); /* node->key > ngx_current_msec */ if ((ngx_msec_int_t) (node->key - ngx_current_msec) > 0) { return; } ev = (ngx_event_t *) ((char *) node - offsetof(ngx_event_t, timer)); 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; ev->timedout = 1; ev->handler(ev); } } ngx_int_t ngx_event_no_timers_left(void) { ngx_event_t *ev; ngx_rbtree_node_t *node, *root, *sentinel; sentinel = ngx_event_timer_rbtree.sentinel; root = ngx_event_timer_rbtree.root; if (root == sentinel) { return NGX_OK; } for (node = ngx_rbtree_min(root, sentinel); node; node = ngx_rbtree_next(&ngx_event_timer_rbtree, node)) { ev = (ngx_event_t *) ((char *) node - offsetof(ngx_event_t, timer)); if (!ev->cancelable) { return NGX_AGAIN; } } /* only cancelable timers left */ return NGX_OK; }