Mercurial > hg > nginx
view src/event/ngx_event_mutex.c @ 3755:76e3a93821b1
fix race condition if during reconfiguration two cache managers try
to delete old inactive entries: one of them removes a entry just locked by
other manager from the queue and the rbtree as long inactive entry,
causes the latter manager to segfault leaving cache mutex locked,
the bug has been introduced in r3727
author | Igor Sysoev <igor@sysoev.ru> |
---|---|
date | Thu, 02 Sep 2010 14:31:47 +0000 |
parents | a88a3e4e158f |
children | d620f497c50f |
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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; }