view src/event/ngx_event_posted.h @ 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 f1720934c45b
children
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/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_EVENT_POSTED_H_INCLUDED_
#define _NGX_EVENT_POSTED_H_INCLUDED_


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_event.h>


#define ngx_post_event(ev, q)                                                 \
                                                                              \
    if (!(ev)->posted) {                                                      \
        (ev)->posted = 1;                                                     \
        ngx_queue_insert_tail(q, &(ev)->queue);                               \
                                                                              \
        ngx_log_debug1(NGX_LOG_DEBUG_CORE, (ev)->log, 0, "post event %p", ev);\
                                                                              \
    } else  {                                                                 \
        ngx_log_debug1(NGX_LOG_DEBUG_CORE, (ev)->log, 0,                      \
                       "update posted event %p", ev);                         \
    }


#define ngx_delete_posted_event(ev)                                           \
                                                                              \
    (ev)->posted = 0;                                                         \
    ngx_queue_remove(&(ev)->queue);                                           \
                                                                              \
    ngx_log_debug1(NGX_LOG_DEBUG_CORE, (ev)->log, 0,                          \
                   "delete posted event %p", ev);



void ngx_event_process_posted(ngx_cycle_t *cycle, ngx_queue_t *posted);
void ngx_event_move_posted_next(ngx_cycle_t *cycle);


extern ngx_queue_t  ngx_posted_accept_events;
extern ngx_queue_t  ngx_posted_next_events;
extern ngx_queue_t  ngx_posted_events;


#endif /* _NGX_EVENT_POSTED_H_INCLUDED_ */