From: Quanah Gibson-Mount <quanah@openldap.org>
Date: Thu, 1 May 2008 23:25:42 +0000 (+0000)
Subject: Fix potential deadlock
X-Git-Tag: OPENLDAP_REL_ENG_2_4_9~13
X-Git-Url: https://git.sur5r.net/?a=commitdiff_plain;h=f1f83aa2ba9499ba83c7ce643e0a29aa7656e837;p=openldap

Fix potential deadlock
---

diff --git a/servers/slapd/back-monitor/cache.c b/servers/slapd/back-monitor/cache.c
index 3de1ce279a..339e2bb4a8 100644
--- a/servers/slapd/back-monitor/cache.c
+++ b/servers/slapd/back-monitor/cache.c
@@ -154,13 +154,18 @@ monitor_cache_get(
 	*ep = NULL;
 
 	tmp_mc.mc_ndn = *ndn;
+retry:;
 	ldap_pvt_thread_mutex_lock( &mi->mi_cache_mutex );
 	mc = ( monitor_cache_t * )avl_find( mi->mi_cache,
 			( caddr_t )&tmp_mc, monitor_cache_cmp );
 
 	if ( mc != NULL ) {
 		/* entry is returned with mutex locked */
-		monitor_cache_lock( mc->mc_e );
+		if ( monitor_cache_trylock( mc->mc_e ) ) {
+			ldap_pvt_thread_mutex_unlock( &mi->mi_cache_mutex );
+			ldap_pvt_thread_yield();
+			goto retry;
+		}
 		*ep = mc->mc_e;
 	}