ITS#9584 serialize refresh phase

Only allow one consumer at a time to perform a refresh on a database.

diff --git a/servers/slapd/syncrepl.c b/servers/slapd/syncrepl.c
index 59f49d3e88e0f5fbfa9028fd2162a850f8980d8a..97ceb38264821f5f6d7caa7d7cf3dd2e8f6db7ab 100644 (file)
--- a/servers/slapd/syncrepl.c
+++ b/servers/slapd/syncrepl.c
@@ -85,6 +85,9 @@ typedef struct cookie_state {
        struct berval *cs_pvals;
        int *cs_psids;
        int     cs_pnum;
+
+       /* serialize multi-consumer refreshes */
+       ldap_pvt_thread_mutex_t cs_refresh_mutex;
 } cookie_state;
 
 #define        SYNCDATA_DEFAULT        0       /* entries are plain LDAP entries */
@@ -915,6 +918,12 @@ check_syncprov(
        return changed;
 }
 
+#define SYNC_TIMEOUT   0
+#define SYNC_SHUTDOWN  -100
+#define SYNC_ERROR             -101
+#define SYNC_REPOLL            -102
+#define SYNC_PAUSED            -103
+
 static int
 do_syncrep1(
        Operation *op,
@@ -928,6 +937,13 @@ do_syncrep1(
        void    *ssl;
 #endif
 
+       while ( ldap_pvt_thread_mutex_trylock( &si->si_cookieState->cs_refresh_mutex )) {
+               if ( slapd_shutdown )
+                       return SYNC_SHUTDOWN;
+               if ( !ldap_pvt_thread_pool_pausecheck( &connection_pool ))
+                       ldap_pvt_thread_yield();
+       }
+
        si->si_lastconnect = slap_get_time();
        si->si_refreshDone = 0;
        rc = slap_client_connect( &si->si_ld, &si->si_bindconf );
@@ -1104,6 +1120,7 @@ done:
                        ldap_unbind_ext( si->si_ld, NULL, NULL );
                        si->si_ld = NULL;
                }
+               ldap_pvt_thread_mutex_unlock( &si->si_cookieState->cs_refresh_mutex );
        }
 
        return rc;
@@ -1184,12 +1201,6 @@ check_csn_age(
        return rc;
 }
 
-#define SYNC_TIMEOUT   0
-#define SYNC_SHUTDOWN  -100
-#define SYNC_ERROR             -101
-#define SYNC_REPOLL            -102
-#define SYNC_PAUSED            -103
-
 static int
 get_pmutex(
        syncinfo_t *si
@@ -1233,6 +1244,7 @@ do_syncrep2(
        struct timeval tout = { 0, 0 };
 
        int             refreshDeletes = 0;
+       int             refreshEnded = 0;
        char empty[6] = "empty";
 
        if ( slapd_shutdown ) {
@@ -1524,6 +1536,7 @@ logerr:
                        Debug( LDAP_DEBUG_SYNC,
                                "do_syncrep2: %s LDAP_RES_SEARCH_RESULT\n",
                                si->si_ridtxt );
+                       refreshEnded = 1;
                        err = LDAP_OTHER; /* FIXME check parse result properly */
                        ldap_parse_result( si->si_ld, msg, &err, NULL, NULL, NULL,
                                &rctrls, 0 );
@@ -1752,8 +1765,9 @@ logerr:
                                        }
                                        ber_scanf( ber, /*"{"*/ "}" );
                                        if ( si->si_refreshDone ) {
-                                               Debug( LDAP_DEBUG_SYNC, "do_syncrep1: %s finished refresh\n",
+                                               Debug( LDAP_DEBUG_SYNC, "do_syncrep2: %s finished refresh\n",
                                                        si->si_ridtxt );
+                                               refreshEnded = 1;
                                        }
                                        break;
                                case LDAP_TAG_SYNC_ID_SET:
@@ -1900,6 +1914,8 @@ done:
                        "do_syncrep2: %s (%d) %s\n",
                        si->si_ridtxt, err, ldap_err2string( err ) );
        }
+       if ( refreshEnded || ( rc && !si->si_refreshDone ))
+               ldap_pvt_thread_mutex_unlock( &si->si_cookieState->cs_refresh_mutex );
 
        slap_sync_cookie_free( &syncCookie, 0 );
        slap_sync_cookie_free( &syncCookie_req, 0 );
@@ -5936,6 +5952,7 @@ syncinfo_free( syncinfo_t *sie, int free_all )
                                ch_free( sie->si_cookieState->cs_psids );
                                ber_bvarray_free( sie->si_cookieState->cs_pvals );
                                ldap_pvt_thread_mutex_destroy( &sie->si_cookieState->cs_pmutex );
+                               ldap_pvt_thread_mutex_destroy( &sie->si_cookieState->cs_refresh_mutex );
                                ch_free( sie->si_cookieState );
                        }
                }
@@ -7147,6 +7164,7 @@ add_syncrepl(
                        si->si_cookieState = ch_calloc( 1, sizeof( cookie_state ));
                        ldap_pvt_thread_mutex_init( &si->si_cookieState->cs_mutex );
                        ldap_pvt_thread_mutex_init( &si->si_cookieState->cs_pmutex );
+                       ldap_pvt_thread_mutex_init( &si->si_cookieState->cs_refresh_mutex );
                        ldap_pvt_thread_cond_init( &si->si_cookieState->cs_cond );
 
                        c->be->be_syncinfo = si;