view src/event/ngx_event_mutex.c @ 4569:1db899642518

Upstream: reject upstreams without normal servers. Such upstreams cause CPU hog later in the code as number of peers isn't expected to be 0. Currently this may happen either if there are only backup servers defined in an upstream block, or if server with ipv6 address used in an upstream block.
author Maxim Dounin <mdounin@mdounin.ru>
date Mon, 02 Apr 2012 21:29:35 +0000
parents d620f497c50f
children 3377f9459e99
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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_int_t ngx_event_mutex_timedlock(ngx_event_mutex_t *m, ngx_msec_t timer,
                                    ngx_event_t *ev)
{
    ngx_log_debug2(NGX_LOG_DEBUG_EVENT, ev->log, 0,
                   "lock event mutex %p lock:%XD", m, m->lock);

    if (m->lock) {

        if (m->events == NULL) {
            m->events = ev;

        } else {
            m->last->next = ev;
        }

        m->last = ev;
        ev->next = NULL;

#if (NGX_THREADS0)
        ev->light = 1;
#endif

        ngx_add_timer(ev, timer);

        return NGX_AGAIN;
    }

    m->lock = 1;

    return NGX_OK;
}


ngx_int_t ngx_event_mutex_unlock(ngx_event_mutex_t *m, ngx_log_t *log)
{
    ngx_event_t  *ev;

    if (m->lock == 0) {
        ngx_log_error(NGX_LOG_ALERT, log, 0,
                      "tring to unlock the free event mutex %p", m);
        return NGX_ERROR;
    }

    ngx_log_debug2(NGX_LOG_DEBUG_EVENT, log, 0,
                   "unlock event mutex %p, next event: %p", m, m->events);

    m->lock = 0;

    if (m->events) {
        ev = m->events;
        m->events = ev->next;

        ev->next = (ngx_event_t *) ngx_posted_events;
        ngx_posted_events = ev;
    }

    return NGX_OK;
}