Bypass a few redundant locks

[openldap] / servers / slapd / back-bdb / cache.c

diff --git a/servers/slapd/back-bdb/cache.c b/servers/slapd/back-bdb/cache.c
index 4dc03f7b7b192ebed540eb60d3741b055770eec6..5c9dc31490405d4a4e79bcadc1cc97e1e9213e57 100644 (file)
--- a/servers/slapd/back-bdb/cache.c
+++ b/servers/slapd/back-bdb/cache.c
@@ -495,13 +495,14 @@ hdb_cache_find_parent(
                        bdb_cache_entryinfo_lock( ei2 );
                        ein->bei_parent = ei2;
 
+                       avl_insert( &ei2->bei_kids, (caddr_t)ein, bdb_rdn_cmp,
+                               avl_dup_error);
+                       ei2->bei_ckids++;
+
                        /* Reset all the state info */
                        for (ein = eir; ein != ei2; ein=ein->bei_parent)
                                ein->bei_state &= ~CACHE_ENTRY_NOT_LINKED;
 
-                       avl_insert( &ei2->bei_kids, (caddr_t)ein, bdb_rdn_cmp,
-                               avl_dup_error);
-                       ei2->bei_ckids++;
                        bdb_cache_entryinfo_unlock( ei2 );
                        bdb_cache_entryinfo_lock( eir );
 
@@ -592,9 +593,13 @@ bdb_cache_lru_purge( struct bdb_info *bdb )
 
                /* If this node is in the process of linking into the cache,
                 * or this node is being deleted, skip it.
+                *
+                * Also, if this node has no entry attached, skip it, there's
+                * nothing to purge anyway.
                 */
-               if ( elru->bei_state & ( CACHE_ENTRY_NOT_LINKED |
-                       CACHE_ENTRY_DELETED | CACHE_ENTRY_LOADING )) {
+               if (( elru->bei_state & ( CACHE_ENTRY_NOT_LINKED |
+                       CACHE_ENTRY_DELETED | CACHE_ENTRY_LOADING )) ||
+                       !elru->bei_e ) {
                        bdb_cache_entryinfo_unlock( elru );
                        continue;
                }
@@ -619,7 +624,7 @@ bdb_cache_lru_purge( struct bdb_info *bdb )
                                elru->bei_e = NULL;
                                count++;
                        }
-                       bdb_cache_entry_dbunlock( bdb, lockp );
+                       bdb_cache_entry_db_unlock( bdb, lockp );
 
                        /* ITS#4010 if we're in slapcat, and this node is a leaf
                         * node, free it.
@@ -649,7 +654,7 @@ bdb_cache_lru_purge( struct bdb_info *bdb )
                }
        }
 
-       bdb->bi_cache.c_lruhead = elru;
+       bdb->bi_cache.c_lruhead = elnext;
        ldap_pvt_thread_mutex_unlock( &bdb->bi_cache.lru_head_mutex );
 }
 
@@ -776,19 +781,13 @@ load1:
                                bdb_cache_entryinfo_unlock( *eip );
                                islocked = 0;
                        }
-                       rc = bdb_cache_entry_db_lock( bdb, locker, *eip, 0, 0, lock );
+                       rc = bdb_cache_entry_db_lock( bdb, locker, *eip, load, 0, lock );
                        if ( (*eip)->bei_state & CACHE_ENTRY_DELETED ) {
                                rc = DB_NOTFOUND;
                                bdb_cache_entry_db_unlock( bdb, lock );
                        } else if ( rc == 0 ) {
                                if ( load ) {
-                                       /* Give up original read lock, obtain write lock
-                                        */
-                                   if ( rc == 0 ) {
-                                               rc = bdb_cache_entry_db_relock( bdb, locker,
-                                                       *eip, 1, 0, lock );
-                                       }
-                                       if ( rc == 0 && !ep) {
+                                       if ( !ep) {
                                                rc = bdb_id2entry( op->o_bd, tid, locker, id, &ep );
                                        }
                                        if ( rc == 0 ) {
@@ -1287,15 +1286,22 @@ bdb_lru_print( Cache *cache )
 {
        EntryInfo       *e;
 
-       fprintf( stderr, "LRU queue (head to tail):\n" );
-       for ( e = cache->c_lruhead; e != NULL; e = e->bei_lrunext ) {
-               fprintf( stderr, "\trdn \"%20s\" id %ld\n",
-                       e->bei_nrdn.bv_val, e->bei_id );
+       fprintf( stderr, "LRU circle head: %p\n", cache->c_lruhead );
+       fprintf( stderr, "LRU circle (tail forward):\n" );
+       for ( e = cache->c_lrutail; ; ) {
+               fprintf( stderr, "\t%p, %p id %ld rdn \"%s\"\n",
+                       e, e->bei_e, e->bei_id, e->bei_nrdn.bv_val );
+               e = e->bei_lrunext;
+               if ( e == cache->c_lrutail )
+                       break;
        }
-       fprintf( stderr, "LRU queue (tail to head):\n" );
-       for ( e = cache->c_lrutail; e != NULL; e = e->bei_lruprev ) {
-               fprintf( stderr, "\trdn \"%20s\" id %ld\n",
-                       e->bei_nrdn.bv_val, e->bei_id );
+       fprintf( stderr, "LRU circle (tail backward):\n" );
+       for ( e = cache->c_lrutail; ; ) {
+               fprintf( stderr, "\t%p, %p id %ld rdn \"%s\"\n",
+                       e, e->bei_e, e->bei_id, e->bei_nrdn.bv_val );
+               e = e->bei_lruprev;
+               if ( e == cache->c_lrutail )
+                       break;
        }
 }
 #endif