view src/event/ngx_event_mutex.c @ 4233:aae172db7ac8

Event pipe: reduced number of file buffers used. If possible we now just extend already present file buffer in p->out chain instead of keeping ngx_buf_t for each buffer we've flushed to disk. This saves about 120 bytes of memory per buffer flushed to disk, and resolves high CPU usage observed in edge cases (due to coalescing these buffers on send).
author Maxim Dounin <mdounin@mdounin.ru>
date Mon, 31 Oct 2011 09:54:55 +0000
parents a88a3e4e158f
children d620f497c50f
line wrap: on
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/*
 * Copyright (C) Igor Sysoev
 */


#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;
}