ITS#10550 slapd-ldap: a connection with an active op is not idle

diff --git a/servers/slapd/back-ldap/bind.c b/servers/slapd/back-ldap/bind.c
index fb84d990a3f268ac256731de3341e7dc0fb31101..e00a2542b400eae2550e2376687af0db850a8979 100644 (file)
--- a/servers/slapd/back-ldap/bind.c
+++ b/servers/slapd/back-ldap/bind.c
@@ -151,6 +151,9 @@ ldap_back_prepare_conn( ldapconn_t *lc, Operation *op, SlapReply *rs,
 static int
 ldap_back_conndnlc_cmp( const void *c1, const void *c2 );
 
+static time_t
+ldap_back_conn_expire_time( ldapinfo_t *li, ldapconn_t *lc, int schedule );
+
 static void
 ldap_back_conn_prune( ldapinfo_t *li );
 
@@ -1116,10 +1119,9 @@ retry_lock:
 
        } else {
                int     expiring = 0;
+               time_t expiry = ldap_back_conn_expire_time( li, lc, 0 );
 
-               if ( ( li->li_idle_timeout != 0 && op->o_time > lc->lc_time + li->li_idle_timeout )
-                       || ( li->li_conn_ttl != 0 && op->o_time > lc->lc_create_time + li->li_conn_ttl ) )
-               {
+               if ( expiry > -1 && expiry < op->o_time ) {
                        expiring = 1;
 
                        /* let it be used, but taint/delete it so that 
@@ -3074,16 +3076,21 @@ ldap_back_conn_expire_fn( void *ctx, void *arg )
 
 /* Pick which expires first: connection TTL or idle timeout */
 static time_t
-ldap_back_conn_expire_time( ldapinfo_t *li, ldapconn_t *lc) {
-       if ( li->li_conn_ttl != 0 && li->li_idle_timeout != 0 ) {
-               return ( lc->lc_create_time + li->li_conn_ttl ) < ( lc->lc_time + li->li_idle_timeout ) ?
-                       ( lc->lc_create_time + li->li_conn_ttl ) : ( lc->lc_time + li->li_idle_timeout );
-       } else if ( li->li_conn_ttl != 0 ) {
-               return lc->lc_create_time + li->li_conn_ttl;
-       } else if ( li->li_idle_timeout != 0 ) {
-               return lc->lc_time + li->li_idle_timeout;
-       }
-       return -1;
+ldap_back_conn_expire_time( ldapinfo_t *li, ldapconn_t *lc, int schedule ) {
+       time_t expiry = -1;
+
+       if ( li->li_conn_ttl != 0 ) {
+               expiry = lc->lc_create_time + li->li_conn_ttl;
+       }
+       if ( li->li_idle_timeout != 0 && ( schedule || lc->lc_refcnt == 0 ) ) {
+               time_t idle_threshold = lc->lc_time + li->li_idle_timeout;
+               if ( expiry < 0 || idle_threshold < expiry ) {
+                       expiry = idle_threshold;
+               }
+       }
+       Debug( LDAP_DEBUG_TRACE, "ldap_back_conn_expire_time lc=%p expire=%ld\n",
+                       lc, expiry );
+       return expiry;
 }
 
 /*
@@ -3108,18 +3115,24 @@ ldap_back_conn_prune( ldapinfo_t *li )
        time_t          now = slap_get_time();
        time_t          next_timeout = -1; /* -1 means uninitialized */
        TAvlnode        *edge;
-       int             c;
+       ldapconn_t      *lc = NULL;
+       int             c, idle_candidates = 0;
 
        ldap_pvt_thread_mutex_lock( &li->li_conninfo.lai_mutex );
 
        for ( c = LDAP_BACK_PCONN_FIRST; c < LDAP_BACK_PCONN_LAST; c++ ) {
-               ldapconn_t *lc = LDAP_TAILQ_FIRST( &li->li_conn_priv[ c ].lic_priv );
+               lc = LDAP_TAILQ_FIRST( &li->li_conn_priv[ c ].lic_priv );
 
                while ( lc ) {
                        ldapconn_t *next = LDAP_TAILQ_NEXT( lc, lc_q );
 
                        if ( !LDAP_BACK_CONN_TAINTED( lc ) ) {
-                               time_t conn_expires = ldap_back_conn_expire_time( li, lc );
+                               time_t conn_expires = ldap_back_conn_expire_time( li, lc, 0 );
+                               if ( conn_expires == -1 ) {
+                                       idle_candidates++;
+                                       lc = next;
+                                       continue;
+                               }
 
                                if ( now >= conn_expires ) {
                                        if ( lc->lc_refcnt == 0 ) {
@@ -3147,10 +3160,15 @@ ldap_back_conn_prune( ldapinfo_t *li )
        edge = ldap_tavl_end( li->li_conninfo.lai_tree, TAVL_DIR_LEFT );
        while ( edge ) {
                TAvlnode *next = ldap_tavl_next( edge, TAVL_DIR_RIGHT );
-               ldapconn_t *lc = (ldapconn_t *)edge->avl_data;
+               lc = (ldapconn_t *)edge->avl_data;
 
                if ( !LDAP_BACK_CONN_TAINTED( lc ) ) {
-                       time_t conn_expires = ldap_back_conn_expire_time( li, lc );
+                       time_t conn_expires = ldap_back_conn_expire_time( li, lc, 0 );
+                       if ( conn_expires == -1 ) {
+                               idle_candidates++;
+                               edge = next;
+                               continue;
+                       }
 
                        if ( now >= conn_expires ) {
                                if ( lc->lc_refcnt == 0 ) {
@@ -3168,12 +3186,19 @@ ldap_back_conn_prune( ldapinfo_t *li )
                                next_timeout = conn_expires;
                        }
                }
-
                edge = next;
        }
 
        ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
 
+       if ( idle_candidates && next_timeout == -1 && li->li_idle_timeout ) {
+               /*
+                * We have no ttl and all connections are busy or tainted already, this
+                * is the first time a connection can legitimately become idle.
+                */
+               next_timeout = now + li->li_idle_timeout;
+       }
+
        /* Reschedule for next timeout or cancel the task */
        ldap_pvt_thread_mutex_lock( &slapd_rq.rq_mutex );
        if ( next_timeout > 0 ) {
@@ -3220,7 +3245,7 @@ ldap_back_schedule_conn_expiry( ldapinfo_t *li, ldapconn_t *lc ) {
                        "ldap_back_conn_expire_timer" );
 
                li->li_conn_expire_task->interval.tv_sec =
-                       ldap_back_conn_expire_time( li, lc ) - slap_get_time();
+                       ldap_back_conn_expire_time( li, lc, 1 ) - slap_get_time();
                ldap_pvt_runqueue_resched( &slapd_rq, li->li_conn_expire_task, 0 );
                Debug( LDAP_DEBUG_TRACE,
                        "ldap_back_conn_prune: scheduled connection expiry timer to %ld sec\n",