queue implicit binds (ITS#4409)

diff --git a/servers/slapd/back-ldap/back-ldap.h b/servers/slapd/back-ldap/back-ldap.h
index 2c14022d2fdeba7ec97ef9ba3175f7f5e8f37451..f6c25b2496b8af314de41ca64f2e0984c5261eb0 100644 (file)
--- a/servers/slapd/back-ldap/back-ldap.h
+++ b/servers/slapd/back-ldap/back-ldap.h
@@ -82,6 +82,7 @@ typedef struct ldapconn_t {
 #define        LDAP_BACK_CONN_BINDING_CLEAR(lc)        LDAP_BACK_CONN_CLEAR((lc), LDAP_BACK_FCONN_BINDING)
 
        unsigned                lc_refcnt;
+       unsigned                lc_binding;
        unsigned                lc_flags;
        time_t                  lc_create_time;
        time_t                  lc_time;

diff --git a/servers/slapd/back-ldap/bind.c b/servers/slapd/back-ldap/bind.c
index 3350c915fa0aa18d6e53405e73ec16d4d1bdd237..b8fc62aaafe67777b32b8c834a23b5d32dfde60a 100644 (file)
--- a/servers/slapd/back-ldap/bind.c
+++ b/servers/slapd/back-ldap/bind.c
@@ -91,6 +91,8 @@ ldap_back_bind( Operation *op, SlapReply *rs )
                        }
                }
 
+               assert( lc->lc_binding == 1 );
+               lc->lc_binding = 0;
                LDAP_BACK_CONN_ISBOUND_SET( lc );
                ber_dupbv( &lc->lc_bound_ndn, &op->o_req_ndn );
 
@@ -465,6 +467,7 @@ ldap_back_prepare_conn( ldapconn_t **lcp, Operation *op, SlapReply *rs, ldap_bac
        }
        (*lcp)->lc_ld = ld;
        (*lcp)->lc_refcnt = 1;
+       (*lcp)->lc_binding = 1;
 #ifdef HAVE_TLS
        if ( is_tls ) {
                LDAP_BACK_CONN_ISTLS_SET( *lcp );
@@ -499,7 +502,7 @@ ldap_back_getconn( Operation *op, SlapReply *rs, ldap_back_send_t sendok )
        ldapinfo_t      *li = (ldapinfo_t *)op->o_bd->be_private;
        ldapconn_t      *lc = NULL,
                        lc_curr = { 0 };
-       int             refcnt = 1;
+       int             refcnt = 1, binding = 1;
 
        /* Internal searches are privileged and shared. So is root. */
        if ( op->o_do_not_cache || be_isroot( op ) ) {
@@ -534,6 +537,7 @@ retry_lock:
                                goto retry_lock;
                        }
                        refcnt = ++lc->lc_refcnt;
+                       binding = ++lc->lc_binding;
                }
                ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
        }
@@ -584,6 +588,7 @@ retry_lock:
                                        (caddr_t)&lc_curr, ldap_back_conndn_cmp );
                        if ( tmplc != NULL ) {
                                refcnt = ++tmplc->lc_refcnt;
+                               binding = ++tmplc->lc_binding;
                                ldap_back_conn_free( lc );
                                lc = tmplc;
                        }
@@ -601,6 +606,7 @@ retry_lock:
                ldap_pvt_thread_mutex_lock( &li->li_conninfo.lai_mutex );
 
                assert( lc->lc_refcnt == 1 );
+               assert( lc->lc_binding == 1 );
                rs->sr_err = avl_insert( &li->li_conninfo.lai_tree, (caddr_t)lc,
                        ldap_back_conndn_cmp, ldap_back_conndn_dup );
 
@@ -611,8 +617,8 @@ retry_lock:
                ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
 
                Debug( LDAP_DEBUG_TRACE,
-                       "=>ldap_back_getconn: conn %p inserted (refcnt=%u)\n",
-                       (void *)lc, refcnt, 0 );
+                       "=>ldap_back_getconn: conn %p inserted refcnt=%u binding=%u\n",
+                       (void *)lc, refcnt, binding );
        
                /* Err could be -1 in case a duplicate ldapconn is inserted */
                if ( rs->sr_err != 0 ) {
@@ -637,8 +643,8 @@ retry_lock:
 
                if ( lc ) {
                        Debug( LDAP_DEBUG_TRACE,
-                               "=>ldap_back_getconn: conn %p fetched (refcnt=%u)\n",
-                               (void *)lc, refcnt, 0 );
+                               "=>ldap_back_getconn: conn %p fetched refcnt=%u binding=%u\n",
+                               (void *)lc, refcnt, binding );
                }
        }
 
@@ -690,15 +696,57 @@ ldap_back_dobind_int(
 {      
        ldapinfo_t      *li = (ldapinfo_t *)op->o_bd->be_private;
 
-       int             rc = LDAP_BACK_CONN_ISBOUND( lc );
+       int             rc, binding = 0;
        ber_int_t       msgid;
 
        assert( retries >= 0 );
 
-       if ( rc ) {
-               return rc;
+retry_lock:;
+       if ( dolock ) {
+               ldap_pvt_thread_mutex_lock( &li->li_conninfo.lai_mutex );
+       }
+
+       if ( binding == 0 ) {
+               /* check if already bound */
+               rc = LDAP_BACK_CONN_ISBOUND( lc );
+               if ( rc ) {
+                       lc->lc_binding--;
+                       if ( dolock ) {
+                               ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
+                       }
+                       return rc;
+               }
+
+               if ( LDAP_BACK_CONN_BINDING( lc ) ) {
+                       /* if someone else is about to bind it, give up and retry */
+                       if ( dolock ) {
+                               ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
+                       }
+                       ldap_pvt_thread_yield();
+                       goto retry_lock;
+
+               } else {
+                       /* otherwise this thread will bind it */
+                       LDAP_BACK_CONN_BINDING_SET( lc );
+                       binding = 1;
+               }
+       }
+
+       /* wait for pending operations to finish */
+       /* FIXME: may become a bottleneck! */
+       if ( lc->lc_refcnt != lc->lc_binding ) {
+               if ( dolock ) {
+                       ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
+               }
+               ldap_pvt_thread_yield();
+               goto retry_lock;
        }
 
+       if ( dolock ) {
+               ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
+       }
+
+#if 0
        while ( lc->lc_refcnt > 1 ) {
                ldap_pvt_thread_yield();
                rc = LDAP_BACK_CONN_ISBOUND( lc );
@@ -714,6 +762,7 @@ ldap_back_dobind_int(
        if ( dolock ) {
                ldap_pvt_thread_mutex_unlock( &li->li_conninfo.lai_mutex );
        }
+#endif
 
        /*
         * FIXME: we need to let clients use proxyAuthz
@@ -822,6 +871,7 @@ retry:;
                        }
                }
 
+               lc->lc_binding--;
                ldap_back_freeconn( op, lc, dolock );
                rs->sr_err = slap_map_api2result( rs );
 
@@ -834,6 +884,7 @@ retry:;
        }
 
 done:;
+       lc->lc_binding--;
        LDAP_BACK_CONN_BINDING_CLEAR( lc );
        rc = LDAP_BACK_CONN_ISBOUND( lc );
        if ( !rc ) {