]> git.sur5r.net Git - openldap/blobdiff - servers/slapd/back-ldbm/cache.c
Initial round of changes for 2.3 beta
[openldap] / servers / slapd / back-ldbm / cache.c
index 01a92295df87d35dbafa2f37994085d77804c814..4cc80c455b022063da98150f0bff2f5e1063736a 100644 (file)
 /* cache.c - routines to maintain an in-core cache of entries */
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 1998-2005 The OpenLDAP Foundation.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted only as authorized by the OpenLDAP
+ * Public License.
+ *
+ * A copy of this license is available in the file LICENSE in the
+ * top-level directory of the distribution or, alternatively, at
+ * <http://www.OpenLDAP.org/license.html>.
+ */
 
 #include "portable.h"
 
 #include <stdio.h>
-int strcasecmp( const char *, const char *);
 
+#include <ac/errno.h>
+#include <ac/string.h>
 #include <ac/socket.h>
+
 #include "slap.h"
 
 #include "back-ldbm.h"
 
-static int     cache_delete_entry_internal(struct cache *cache, Entry *e);
+/* LDBM backend specific entry info -- visible only to the cache */
+typedef struct ldbm_entry_info {
+       /*
+        * These items are specific to the LDBM backend and should
+        * be hidden.  Backend cache lock required to access.
+        */
+       int             lei_state;      /* for the cache */
+#define        CACHE_ENTRY_UNDEFINED   0
+#define CACHE_ENTRY_CREATING   1
+#define CACHE_ENTRY_READY      2
+#define CACHE_ENTRY_DELETED    3
+#define CACHE_ENTRY_COMMITTED  4
+       
+       int             lei_refcnt;     /* # threads ref'ing this entry */
+       Entry   *lei_lrunext;   /* for cache lru list */
+       Entry   *lei_lruprev;
+} EntryInfo;
+#undef LEI
+#define LEI(e) ((EntryInfo *) ((e)->e_private))
+
+static int     cache_delete_entry_internal(Cache *cache, Entry *e);
 #ifdef LDAP_DEBUG
-static void    lru_print(struct cache *cache);
+static void    lru_print(Cache *cache);
 #endif
 
-/*
- * the cache has three entry points (ways to find things):
- *
- *     by entry        e.g., if you already have an entry from the cache
- *                     and want to delete it. (really by entry ptr)
- *     by dn           e.g., when looking for the base object of a search
- *     by id           e.g., for search candidates
- *
- * these correspond to three different avl trees that are maintained.
- */
-
 static int
-cache_entry_cmp( Entry *e1, Entry *e2 )
+cache_entry_private_init( Entry*e )
 {
-       return( e1 < e2 ? -1 : (e1 > e2 ? 1 : 0) );
+       assert( e->e_private == NULL );
+
+       if( e->e_private != NULL ) {
+               /* this should never happen */
+               return 1;
+       }
+
+       e->e_private = ch_calloc(1, sizeof(struct ldbm_entry_info));
+
+       return 0;
 }
 
-static int
-cache_entrydn_cmp( Entry *e1, Entry *e2 )
+/*
+ * marks an entry in CREATING state as committed, so it is really returned
+ * to the cache. Otherwise an entry in CREATING state is removed.
+ * Makes e_private be destroyed at the following cache_return_entry_w,
+ * but lets the entry untouched (owned by someone else)
+ */
+void
+cache_entry_commit( Entry *e )
 {
-       return( strcasecmp( e1->e_dn, e2->e_dn ) );
+       assert( e );
+       assert( e->e_private );
+       assert( LEI(e)->lei_state == CACHE_ENTRY_CREATING );
+       /* assert( LEI(e)->lei_refcnt == 1 ); */
+
+       LEI(e)->lei_state = CACHE_ENTRY_COMMITTED;
 }
 
 static int
-cache_entryid_cmp( Entry *e1, Entry *e2 )
+cache_entry_private_destroy( Entry*e )
 {
-       return( e1->e_id < e2->e_id ? -1 : (e1->e_id > e2->e_id ? 1 : 0) );
+       assert( e->e_private );
+
+       free( e->e_private );
+       e->e_private = NULL;
+       return 0;
 }
 
 void
-cache_set_state( struct cache *cache, Entry *e, int state )
+cache_return_entry_rw( Cache *cache, Entry *e, int rw )
 {
-       /* set cache mutex */
-       pthread_mutex_lock( &cache->c_mutex );
+       ID id;
+       int refcnt, freeit = 1;
 
-       e->e_state = state;
-
-       /* free cache mutex */
-       pthread_mutex_unlock( &cache->c_mutex );
-}
+       if ( slapMode != SLAP_SERVER_MODE ) {
+               return;
+       }
 
-static void
-cache_return_entry( struct cache *cache, Entry *e )
-{
        /* set cache mutex */
-       pthread_mutex_lock( &cache->c_mutex );
+       ldap_pvt_thread_mutex_lock( &cache->c_mutex );
 
-       if ( --e->e_refcnt == 0 && e->e_state == ENTRY_STATE_DELETED ) {
-               entry_free( e );
+       assert( e->e_private );
+
+       id = e->e_id;
+       refcnt = --LEI(e)->lei_refcnt;
+
+       /*
+        * if the entry is returned when in CREATING state, it is deleted
+        * but not freed because it may belong to someone else (do_add,
+        * for instance)
+        */
+       if (  LEI(e)->lei_state == CACHE_ENTRY_CREATING ) {
+               cache_delete_entry_internal( cache, e );
+               freeit = 0;
+               /* now the entry is in DELETED state */
        }
 
-       /* free cache mutex */
-       pthread_mutex_unlock( &cache->c_mutex );
-}
+       if ( LEI(e)->lei_state == CACHE_ENTRY_COMMITTED ) {
+               LEI(e)->lei_state = CACHE_ENTRY_READY;
 
-static void
-cache_return_entry_rw( struct cache *cache, Entry *e, int rw )
-{
-       Debug( LDAP_DEBUG_TRACE, "====> cache_return_entry_%s\n",
-               rw ? "w" : "r", 0, 0);
-       entry_rdwr_unlock(e, rw);;
-       cache_return_entry(cache, e);
-}
+               /* free cache mutex */
+               ldap_pvt_thread_mutex_unlock( &cache->c_mutex );
 
-void
-cache_return_entry_r( struct cache *cache, Entry *e )
-{
-       cache_return_entry_rw(cache, e, 0);
-}
+               Debug( LDAP_DEBUG_TRACE,
+                       "====> cache_return_entry_%s( %ld ): created (%d)\n",
+                       rw ? "w" : "r", id, refcnt );
 
-void
-cache_return_entry_w( struct cache *cache, Entry *e )
-{
-       cache_return_entry_rw(cache, e, 1);
-}
+       } else if ( LEI(e)->lei_state == CACHE_ENTRY_DELETED ) {
+               if( refcnt > 0 ) {
+                       /* free cache mutex */
+                       ldap_pvt_thread_mutex_unlock( &cache->c_mutex );
+
+                       Debug( LDAP_DEBUG_TRACE,
+                               "====> cache_return_entry_%s( %ld ): delete pending (%d)\n",
+                               rw ? "w" : "r", id, refcnt );
 
+               } else {
+                       cache_entry_private_destroy( e );
+                       if ( freeit ) {
+                               entry_free( e );
+                       }
 
-#define LRU_DELETE( cache, e ) { \
-       if ( e->e_lruprev != NULL ) { \
-               e->e_lruprev->e_lrunext = e->e_lrunext; \
+                       /* free cache mutex */
+                       ldap_pvt_thread_mutex_unlock( &cache->c_mutex );
+
+                       Debug( LDAP_DEBUG_TRACE,
+                               "====> cache_return_entry_%s( %ld ): deleted (%d)\n",
+                               rw ? "w" : "r", id, refcnt );
+               }
+
+       } else {
+               /* free cache mutex */
+               ldap_pvt_thread_mutex_unlock( &cache->c_mutex );
+
+               Debug( LDAP_DEBUG_TRACE,
+                       "====> cache_return_entry_%s( %ld ): returned (%d)\n",
+                       rw ? "w" : "r", id, refcnt);
+       }
+}
+
+#define LRU_DELETE( cache, e ) do { \
+       if ( LEI(e)->lei_lruprev != NULL ) { \
+               LEI(LEI(e)->lei_lruprev)->lei_lrunext = LEI(e)->lei_lrunext; \
        } else { \
-               cache->c_lruhead = e->e_lrunext; \
+               (cache)->c_lruhead = LEI(e)->lei_lrunext; \
        } \
-       if ( e->e_lrunext != NULL ) { \
-               e->e_lrunext->e_lruprev = e->e_lruprev; \
+       if ( LEI(e)->lei_lrunext != NULL ) { \
+               LEI(LEI(e)->lei_lrunext)->lei_lruprev = LEI(e)->lei_lruprev; \
        } else { \
-               cache->c_lrutail = e->e_lruprev; \
+               (cache)->c_lrutail = LEI(e)->lei_lruprev; \
        } \
-}
+} while(0)
 
-#define LRU_ADD( cache, e ) { \
-       e->e_lrunext = cache->c_lruhead; \
-       if ( e->e_lrunext != NULL ) { \
-               e->e_lrunext->e_lruprev = e; \
+#define LRU_ADD( cache, e ) do { \
+       LEI(e)->lei_lrunext = (cache)->c_lruhead; \
+       if ( LEI(e)->lei_lrunext != NULL ) { \
+               LEI(LEI(e)->lei_lrunext)->lei_lruprev = (e); \
        } \
-       cache->c_lruhead = e; \
-       e->e_lruprev = NULL; \
-       if ( cache->c_lrutail == NULL ) { \
-               cache->c_lrutail = e; \
+       (cache)->c_lruhead = (e); \
+       LEI(e)->lei_lruprev = NULL; \
+       if ( (cache)->c_lrutail == NULL ) { \
+               (cache)->c_lrutail = (e); \
        } \
-}
+} while(0)
 
 /*
- * cache_create_entry_lock - create an entry in the cache, and lock it.
+ * cache_add_entry_rw - create and lock an entry in the cache
  * returns:    0       entry has been created and locked
  *             1       entry already existed
  *             -1      something bad happened
  */
 int
-cache_add_entry_lock(
-    struct cache       *cache,
+cache_add_entry_rw(
+    Cache      *cache,
     Entry              *e,
-    int                        state
+       int             rw
 )
 {
        int     i, rc;
        Entry   *ee;
 
        /* set cache mutex */
-       pthread_mutex_lock( &cache->c_mutex );
+       ldap_pvt_thread_mutex_lock( &cache->c_mutex );
+
+       assert( e->e_private == NULL );
+
+       if( cache_entry_private_init(e) != 0 ) {
+               /* free cache mutex */
+               ldap_pvt_thread_mutex_unlock( &cache->c_mutex );
+
+               Debug( LDAP_DEBUG_ANY,
+                       "====> cache_add_entry( %ld ): \"%s\": private init failed!\n",
+                   e->e_id, e->e_dn, 0 );
+
+               return( -1 );
+       }
 
        if ( avl_insert( &cache->c_dntree, (caddr_t) e,
-               cache_entrydn_cmp, avl_dup_error ) != 0 )
+                        entry_dn_cmp, avl_dup_error ) != 0 )
        {
+               /* free cache mutex */
+               ldap_pvt_thread_mutex_unlock( &cache->c_mutex );
+
                Debug( LDAP_DEBUG_TRACE,
-                       "====> cache_add_entry lock: entry %20s id %lu already in dn cache\n",
-                   e->e_dn, e->e_id, 0 );
+                       "====> cache_add_entry( %ld ): \"%s\": already in dn cache\n",
+                   e->e_id, e->e_dn, 0 );
+
+               cache_entry_private_destroy(e);
 
-               /* free cache mutex */
-               pthread_mutex_unlock( &cache->c_mutex );
                return( 1 );
        }
 
        /* id tree */
        if ( avl_insert( &cache->c_idtree, (caddr_t) e,
-               cache_entryid_cmp, avl_dup_error ) != 0 )
+                        entry_id_cmp, avl_dup_error ) != 0 )
        {
                Debug( LDAP_DEBUG_ANY,
-                       "====> entry %20s id %lu already in id cache\n",
-                   e->e_dn, e->e_id, 0 );
+                       "====> cache_add_entry( %ld ): \"%s\": already in id cache\n",
+                   e->e_id, e->e_dn, 0 );
 
                /* delete from dn tree inserted above */
                if ( avl_delete( &cache->c_dntree, (caddr_t) e,
-                       cache_entrydn_cmp ) == NULL )
+                                entry_dn_cmp ) == NULL )
                {
                        Debug( LDAP_DEBUG_ANY, "====> can't delete from dn cache\n",
                            0, 0, 0 );
                }
 
+               cache_entry_private_destroy(e);
+
                /* free cache mutex */
-               pthread_mutex_unlock( &cache->c_mutex );
+               ldap_pvt_thread_mutex_unlock( &cache->c_mutex );
                return( -1 );
        }
 
-       e->e_state = state;
-       e->e_refcnt = 1;
+       /* put the entry into 'CREATING' state */
+       /* will be marked after when entry is returned */
+       LEI(e)->lei_state = CACHE_ENTRY_CREATING;
+       LEI(e)->lei_refcnt = 1;
 
        /* lru */
        LRU_ADD( cache, e );
@@ -181,8 +274,10 @@ cache_add_entry_lock(
                 * first 10 on the tail of the list.
                 */
                i = 0;
-               while ( cache->c_lrutail != NULL && cache->c_lrutail->e_refcnt
-                   != 0 && i < 10 ) {
+               while ( cache->c_lrutail != NULL &&
+                       LEI(cache->c_lrutail)->lei_refcnt != 0 &&
+                       i < 10 )
+               {
                        /* move this in-use entry to the front of the q */
                        ee = cache->c_lrutail;
                        LRU_DELETE( cache, ee );
@@ -194,107 +289,195 @@ cache_add_entry_lock(
                 * found at least one to delete - try to get back under
                 * the max cache size.
                 */
-               while ( cache->c_lrutail != NULL && cache->c_lrutail->e_refcnt
-                    == 0 && cache->c_cursize > cache->c_maxsize ) {
+               while ( cache->c_lrutail != NULL &&
+                       LEI(cache->c_lrutail)->lei_refcnt == 0 &&
+                       cache->c_cursize > cache->c_maxsize )
+               {
                        e = cache->c_lrutail;
 
-                       /* XXX check for writer lock - should also check no readers pending */
-#ifdef LDAP_DEBUG
-                       assert(!pthread_rdwr_rwchk_np(&e->e_rdwr));
-#endif
-
                        /* delete from cache and lru q */
+                       /* XXX do we need rc ? */
                        rc = cache_delete_entry_internal( cache, e );
-
+                       cache_entry_private_destroy( e );
                        entry_free( e );
                }
        }
 
        /* free cache mutex */
-       pthread_mutex_unlock( &cache->c_mutex );
+       ldap_pvt_thread_mutex_unlock( &cache->c_mutex );
        return( 0 );
 }
 
 /*
- * cache_find_entry_dn2id - find an entry in the cache, given dn
+ * cache_update_entry - update a LOCKED entry which has been deleted.
+ * returns:    0       entry has been created and locked
+ *             1       entry already existed
+ *             -1      something bad happened
  */
-
-ID
-cache_find_entry_dn2id(
-       Backend         *be,
-    struct cache       *cache,
-    char               *dn
+int
+cache_update_entry(
+    Cache      *cache,
+    Entry              *e
 )
 {
-       struct ldbminfo *li = (struct ldbminfo *) be->be_private;
-       Entry           e, *ep;
-       ID                      id;
+       int     i, rc;
+       Entry   *ee;
 
        /* set cache mutex */
-       pthread_mutex_lock( &cache->c_mutex );
+       ldap_pvt_thread_mutex_lock( &cache->c_mutex );
 
-       e.e_dn = dn;
+       assert( e->e_private );
 
-       if ( (ep = (Entry *) avl_find( cache->c_dntree, (caddr_t) &e,
-               cache_entrydn_cmp )) != NULL )
+       if ( avl_insert( &cache->c_dntree, (caddr_t) e,
+                        entry_dn_cmp, avl_dup_error ) != 0 )
        {
-               Debug(LDAP_DEBUG_TRACE, "====> cache_find_entry_dn2id: found dn: %s\n",
-                       dn, 0, 0);
+               Debug( LDAP_DEBUG_TRACE,
+                       "====> cache_update_entry( %ld ): \"%s\": already in dn cache\n",
+                   e->e_id, e->e_dn, 0 );
+
+               /* free cache mutex */
+               ldap_pvt_thread_mutex_unlock( &cache->c_mutex );
+               return( 1 );
+       }
+
+       /* id tree */
+       if ( avl_insert( &cache->c_idtree, (caddr_t) e,
+                        entry_id_cmp, avl_dup_error ) != 0 )
+       {
+               Debug( LDAP_DEBUG_ANY,
+                       "====> cache_update_entry( %ld ): \"%s\": already in id cache\n",
+                   e->e_id, e->e_dn, 0 );
+
+               /* delete from dn tree inserted above */
+               if ( avl_delete( &cache->c_dntree, (caddr_t) e,
+                                entry_dn_cmp ) == NULL )
+               {
+                       Debug( LDAP_DEBUG_ANY, "====> can't delete from dn cache\n",
+                           0, 0, 0 );
+               }
 
+               /* free cache mutex */
+               ldap_pvt_thread_mutex_unlock( &cache->c_mutex );
+               return( -1 );
+       }
+
+       /* put the entry into 'CREATING' state */
+       /* will be marked after when entry is returned */
+       LEI(e)->lei_state = CACHE_ENTRY_CREATING;
+
+       /* lru */
+       LRU_ADD( cache, e );
+       if ( ++cache->c_cursize > cache->c_maxsize ) {
                /*
-                * entry is deleted or not fully created yet
+                * find the lru entry not currently in use and delete it.
+                * in case a lot of entries are in use, only look at the
+                * first 10 on the tail of the list.
                 */
-               if ( ep->e_state == ENTRY_STATE_DELETED ||
-                       ep->e_state == ENTRY_STATE_CREATING )
+               i = 0;
+               while ( cache->c_lrutail != NULL &&
+                       LEI(cache->c_lrutail)->lei_refcnt != 0 &&
+                       i < 10 )
                {
-                       /* free cache mutex */
-                       pthread_mutex_unlock( &cache->c_mutex );
-                       return( NOID );
+                       /* move this in-use entry to the front of the q */
+                       ee = cache->c_lrutail;
+                       LRU_DELETE( cache, ee );
+                       LRU_ADD( cache, ee );
+                       i++;
                }
 
-               /* XXX is this safe without writer lock? */
-               ep->e_refcnt++;
+               /*
+                * found at least one to delete - try to get back under
+                * the max cache size.
+                */
+               while ( cache->c_lrutail != NULL &&
+                       LEI(cache->c_lrutail)->lei_refcnt == 0 &&
+                       cache->c_cursize > cache->c_maxsize )
+               {
+                       e = cache->c_lrutail;
 
-               /* lru */
-               LRU_DELETE( cache, ep );
-               LRU_ADD( cache, ep );
+                       /* delete from cache and lru q */
+                       /* XXX do we need rc ? */
+                       rc = cache_delete_entry_internal( cache, e );
+                       cache_entry_private_destroy( e );
+                       entry_free( e );
+               }
+       }
 
-               /* acquire reader lock */
-               entry_rdwr_lock(ep, 0);
+       /* free cache mutex */
+       ldap_pvt_thread_mutex_unlock( &cache->c_mutex );
+       return( 0 );
+}
 
-               /* re-check */
-               if ( ep->e_state == ENTRY_STATE_DELETED ||
-                       ep->e_state == ENTRY_STATE_CREATING )
-               {
-                       /* XXX check that is is required */
-                       ep->e_refcnt--;
+ID
+cache_find_entry_ndn2id(
+       Backend         *be,
+    Cache      *cache,
+    struct berval      *ndn
+)
+{
+       Entry           e, *ep;
+       ID                      id;
+       int count = 0;
 
-                       /* free reader lock */
-                       entry_rdwr_unlock(ep, 0);
-                       /* free cache mutex */
-                       pthread_mutex_unlock( &cache->c_mutex );
+       /* this function is always called with normalized DN */
+       e.e_nname = *ndn;
 
-                       return( NOID );
-               }
+try_again:
+       /* set cache mutex */
+       ldap_pvt_thread_mutex_lock( &cache->c_mutex );
+
+       if ( (ep = (Entry *) avl_find( cache->c_dntree, (caddr_t) &e,
+                                      entry_dn_cmp )) != NULL )
+       {
+               int state;
+               count++;
+
+               /*
+                * ep now points to an unlocked entry
+                * we do not need to lock the entry if we only
+                * check the state, refcnt, LRU, and id.
+                */
+               assert( ep->e_private );
 
                /* save id */
                id = ep->e_id;
+               state = LEI(ep)->lei_state;
 
-               /* free reader lock */
-               entry_rdwr_unlock(ep, 0);
+               /*
+                * entry is deleted or not fully created yet
+                */
+               if ( state != CACHE_ENTRY_READY ) {
+                       assert(state != CACHE_ENTRY_UNDEFINED);
 
+                       /* free cache mutex */
+                       ldap_pvt_thread_mutex_unlock( &cache->c_mutex );
+
+                       Debug(LDAP_DEBUG_TRACE,
+                               "====> cache_find_entry_ndn2id(\"%s\"): %ld (not ready) %d\n",
+                               ndn->bv_val, id, state);
+
+                       ldap_pvt_thread_yield();
+                       goto try_again;
+               }
+
+               /* lru */
+               LRU_DELETE( cache, ep );
+               LRU_ADD( cache, ep );
+               
                /* free cache mutex */
-               pthread_mutex_unlock( &cache->c_mutex );
+               ldap_pvt_thread_mutex_unlock( &cache->c_mutex );
 
-               cache_return_entry( &li->li_cache, ep );
+               Debug(LDAP_DEBUG_TRACE,
+                       "====> cache_find_entry_ndn2id(\"%s\"): %ld (%d tries)\n",
+                       ndn->bv_val, id, count);
 
-               return( id );
+       } else {
+               /* free cache mutex */
+               ldap_pvt_thread_mutex_unlock( &cache->c_mutex );
+               id = NOID;
        }
 
-       /* free cache mutex */
-       pthread_mutex_unlock( &cache->c_mutex );
-
-       return( NOID );
+       return( id );
 }
 
 /*
@@ -303,74 +486,69 @@ cache_find_entry_dn2id(
 
 Entry *
 cache_find_entry_id(
-       struct cache    *cache,
+       Cache   *cache,
        ID                              id,
        int                             rw
 )
 {
        Entry   e;
        Entry   *ep;
-
-       /* set cache mutex */
-       pthread_mutex_lock( &cache->c_mutex );
+       int     count = 0;
 
        e.e_id = id;
 
+try_again:
+       /* set cache mutex */
+       ldap_pvt_thread_mutex_lock( &cache->c_mutex );
+
        if ( (ep = (Entry *) avl_find( cache->c_idtree, (caddr_t) &e,
-               cache_entryid_cmp )) != NULL )
+                                      entry_id_cmp )) != NULL )
        {
-               Debug(LDAP_DEBUG_TRACE,
-                       "====> cache_find_entry_dn2id: found id: %ld rw: %d\n",
-                       id, rw, 0);
+               int state;
+               ID      ep_id;
+
+               count++;
+
+               assert( ep->e_private );
+
+               ep_id = ep->e_id; 
+               state = LEI(ep)->lei_state;
 
                /*
                 * entry is deleted or not fully created yet
                 */
-               if ( ep->e_state == ENTRY_STATE_DELETED ||
-                       ep->e_state == ENTRY_STATE_CREATING )
-               {
+               if ( state != CACHE_ENTRY_READY ) {
+                       assert(state != CACHE_ENTRY_UNDEFINED);
+
                        /* free cache mutex */
-                       pthread_mutex_unlock( &cache->c_mutex );
-                       return( NULL );
+                       ldap_pvt_thread_mutex_unlock( &cache->c_mutex );
+
+                       Debug(LDAP_DEBUG_TRACE,
+                               "====> cache_find_entry_id( %ld ): %ld (not ready) %d\n",
+                               id, ep_id, state);
+
+                       ldap_pvt_thread_yield();
+                       goto try_again;
                }
-               /* XXX is this safe without writer lock? */
-               ep->e_refcnt++;
 
                /* lru */
                LRU_DELETE( cache, ep );
                LRU_ADD( cache, ep );
-                
-               /* acquire reader lock */
-               entry_rdwr_lock(ep, 0);
-
-               /* re-check */
-               if ( ep->e_state == ENTRY_STATE_DELETED ||
-                       ep->e_state == ENTRY_STATE_CREATING ) {
-
-                       /* XXX check that is is required */
-                       ep->e_refcnt--;
-
-                       /* free reader lock */
-                       entry_rdwr_unlock(ep, 0);
-
-                       /* free cache mutex */
-                       pthread_mutex_unlock( &cache->c_mutex );
-                       return( NULL );
-               }
-
-               if ( rw ) {
-                       entry_rdwr_unlock(ep, 0);
-                       entry_rdwr_lock(ep, 1);
-               }
+               
+               LEI(ep)->lei_refcnt++;
 
                /* free cache mutex */
-               pthread_mutex_unlock( &cache->c_mutex );
+               ldap_pvt_thread_mutex_unlock( &cache->c_mutex );
+
+               Debug(LDAP_DEBUG_TRACE,
+                       "====> cache_find_entry_id( %ld ) \"%s\" (found) (%d tries)\n",
+                       ep_id, ep->e_dn, count);
 
                return( ep );
        }
 
        /* free cache mutex */
-       pthread_mutex_unlock( &cache->c_mutex );
+       ldap_pvt_thread_mutex_unlock( &cache->c_mutex );
 
        return( NULL );
 }
@@ -388,47 +566,43 @@ cache_find_entry_id(
  */
 int
 cache_delete_entry(
-    struct cache       *cache,
+    Cache      *cache,
     Entry              *e
 )
 {
        int     rc;
 
-       Debug( LDAP_DEBUG_TRACE, "====> cache_delete_entry:\n", 0, 0, 0 );
+       /* set cache mutex */
+       ldap_pvt_thread_mutex_lock( &cache->c_mutex );
 
-       /* XXX check for writer lock - should also check no readers pending */
-#ifdef LDAP_DEBUG
-       assert(pthread_rdwr_wchk_np(&e->e_rdwr));
-#endif
+       assert( e->e_private );
 
-       /* set cache mutex */
-       pthread_mutex_lock( &cache->c_mutex );
+       Debug( LDAP_DEBUG_TRACE, "====> cache_delete_entry( %ld )\n",
+               e->e_id, 0, 0 );
 
        rc = cache_delete_entry_internal( cache, e );
 
        /* free cache mutex */
-       pthread_mutex_unlock( &cache->c_mutex );
+       ldap_pvt_thread_mutex_unlock( &cache->c_mutex );
        return( rc );
 }
 
 static int
 cache_delete_entry_internal(
-    struct cache       *cache,
+    Cache      *cache,
     Entry              *e
 )
 {
-       int rc = 0;     /* return code */
+       int rc = 0;     /* return code */
 
        /* dn tree */
-       if ( avl_delete( &cache->c_dntree, (caddr_t) e, cache_entrydn_cmp )
-               == NULL )
+       if ( avl_delete( &cache->c_dntree, (caddr_t) e, entry_dn_cmp ) == NULL )
        {
                rc = -1;
        }
 
        /* id tree */
-       if ( avl_delete( &cache->c_idtree, (caddr_t) e, cache_entryid_cmp )
-               == NULL )
+       if ( avl_delete( &cache->c_idtree, (caddr_t) e, entry_id_cmp ) == NULL )
        {
                rc = -1;
        }
@@ -444,29 +618,54 @@ cache_delete_entry_internal(
        /*
         * flag entry to be freed later by a call to cache_return_entry()
         */
-       e->e_state = ENTRY_STATE_DELETED;
+       LEI(e)->lei_state = CACHE_ENTRY_DELETED;
 
        return( 0 );
 }
 
-#ifdef LDAP_DEBUG
+void
+cache_release_all( Cache *cache )
+{
+       Entry *e;
+       int rc;
+
+       /* set cache mutex */
+       ldap_pvt_thread_mutex_lock( &cache->c_mutex );
 
+       Debug( LDAP_DEBUG_TRACE, "====> cache_release_all\n", 0, 0, 0 );
+
+
+       while ( (e = cache->c_lrutail) != NULL && LEI(e)->lei_refcnt == 0 ) {
+               /* delete from cache and lru q */
+               /* XXX do we need rc ? */
+               rc = cache_delete_entry_internal( cache, e );
+               cache_entry_private_destroy( e );
+               entry_free( e );
+       }
+
+       if ( cache->c_cursize ) {
+               Debug( LDAP_DEBUG_TRACE, "Entry-cache could not be emptied\n", 0, 0, 0 );
+       }
+
+       /* free cache mutex */
+       ldap_pvt_thread_mutex_unlock( &cache->c_mutex );
+}
+
+#ifdef LDAP_DEBUG
 static void
-lru_print( struct cache *cache )
+lru_print( Cache *cache )
 {
        Entry   *e;
 
        fprintf( stderr, "LRU queue (head to tail):\n" );
-       for ( e = cache->c_lruhead; e != NULL; e = e->e_lrunext ) {
-               fprintf( stderr, "\tdn %20s id %lu refcnt %d\n", e->e_dn,
-                   e->e_id, e->e_refcnt );
+       for ( e = cache->c_lruhead; e != NULL; e = LEI(e)->lei_lrunext ) {
+               fprintf( stderr, "\tdn \"%20s\" id %ld refcnt %d\n",
+                       e->e_dn, e->e_id, LEI(e)->lei_refcnt );
        }
        fprintf( stderr, "LRU queue (tail to head):\n" );
-       for ( e = cache->c_lrutail; e != NULL; e = e->e_lruprev ) {
-               fprintf( stderr, "\tdn %20s id %lu refcnt %d\n", e->e_dn,
-                   e->e_id, e->e_refcnt );
+       for ( e = cache->c_lrutail; e != NULL; e = LEI(e)->lei_lruprev ) {
+               fprintf( stderr, "\tdn \"%20s\" id %ld refcnt %d\n",
+                       e->e_dn, e->e_id, LEI(e)->lei_refcnt );
        }
 }
-
 #endif
-