view src/event/ngx_event_posted.h @ 6635:6acaa638fa07

Events: support for EPOLLEXCLUSIVE. This flag appeared in Linux 4.5 and is useful for avoiding thundering herd problem. The current Linux kernel implementation walks the list of exclusive waiters, and queues an event to each epfd, until it finds the first waiter that has threads blocked on it via epoll_wait().
author Valentin Bartenev <vbart@nginx.com>
date Fri, 15 Jul 2016 15:18:57 +0300
parents 3d4730eada9c
children 9d2ad2fb4423
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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);


extern ngx_queue_t  ngx_posted_accept_events;
extern ngx_queue_t  ngx_posted_events;


#endif /* _NGX_EVENT_POSTED_H_INCLUDED_ */