ITS#6095

diff --git a/CHANGES b/CHANGES
index 5f827b7d44c034d1d96a3969ca85f70d158c5407..386df8fcedf92ce42f8b1d55e7481fc8b08a5fbf 100644 (file)
--- a/CHANGES
+++ b/CHANGES
@@ -12,8 +12,9 @@ OpenLDAP 2.4.17 Engineering
        Fixed slapd normalization of updated schema attributes (ITS#5540)
        Fixed slapd pagedresults stacked control with overlays (ITS#6056)
        Fixed slapd sockets usage on windows (ITS#6039)
-       Fixed slapd-bdb freeing of already freed entries (ITS#6074)
-       Fixed slapd-bdb entryinfo cleanup (ITS#6088)
+       Fixed slapd-hdb freeing of already freed entries (ITS#6074)
+       Fixed slapd-hdb entryinfo cleanup (ITS#6088)
+       Fixed slapd-hdb dncache lockups (ITS#6095)
        Added slapo-rwm rwm-drop-unrequested-attrs config option (ITS#6057)
        Fixed slapo-rwm dn passing (ITS#6070)
        Fixed slapo-rwm entry free (ITS#6058)

diff --git a/servers/slapd/back-bdb/back-bdb.h b/servers/slapd/back-bdb/back-bdb.h
index 0219e3ff14056d153a3536c058279de30daa2340..16bc3dc3538acfb3404beb20e6f7e5ff07980237 100644 (file)
--- a/servers/slapd/back-bdb/back-bdb.h
+++ b/servers/slapd/back-bdb/back-bdb.h
@@ -92,6 +92,7 @@ typedef struct bdb_entry_info {
 #define        CACHE_ENTRY_ONELEVEL    0x40
 #define        CACHE_ENTRY_REFERENCED  0x80
 #define        CACHE_ENTRY_NOT_CACHED  0x100
+#define        CACHE_ENTRY_PURGED      0x200
        int bei_finders;
 
        /*

diff --git a/servers/slapd/back-bdb/cache.c b/servers/slapd/back-bdb/cache.c
index a20d772026b088dab805783916958dab54c6d497..216816c6ca7ed1a44fa8bdfa536ead2edfbef2de 100644 (file)
--- a/servers/slapd/back-bdb/cache.c
+++ b/servers/slapd/back-bdb/cache.c
@@ -94,10 +94,14 @@ bdb_cache_entryinfo_free( Cache *cache, EntryInfo *ei )
        ei->bei_kids = NULL;
        ei->bei_lruprev = NULL;
 
+#if 0
        ldap_pvt_thread_mutex_lock( &cache->c_eifree_mutex );
        ei->bei_lrunext = cache->c_eifree;
        cache->c_eifree = ei;
        ldap_pvt_thread_mutex_unlock( &cache->c_eifree_mutex );
+#else
+       ch_free( ei );
+#endif
 }
 
 #define LRU_DEL( c, e ) do { \
@@ -334,8 +338,8 @@ bdb_entryinfo_add_internal(
 
        ei2 = bdb_cache_entryinfo_new( &bdb->bi_cache );
 
-       ldap_pvt_thread_rdwr_wlock( &bdb->bi_cache.c_rwlock );
        bdb_cache_entryinfo_lock( ei->bei_parent );
+       ldap_pvt_thread_rdwr_wlock( &bdb->bi_cache.c_rwlock );
 
        ei2->bei_id = ei->bei_id;
        ei2->bei_parent = ei->bei_parent;
@@ -372,13 +376,11 @@ bdb_entryinfo_add_internal(
                        bdb->bi_cache.c_leaves++;
                rc = avl_insert( &ei->bei_parent->bei_kids, ei2, bdb_rdn_cmp,
                        avl_dup_error );
-               if ( rc ) {
-                       /* This should never happen; entry cache is corrupt */
-                       bdb->bi_dbenv->log_flush( bdb->bi_dbenv, NULL );
-                       assert( !rc );
-               }
 #ifdef BDB_HIER
-               ei->bei_parent->bei_ckids++;
+               /* it's possible for hdb_cache_find_parent to beat us to it */
+               if ( !rc ) {
+                       ei->bei_parent->bei_ckids++;
+               }
 #endif
        }
 
@@ -443,6 +445,7 @@ bdb_cache_find_ndn(
 
                        ei.bei_nrdn.bv_len = ndn->bv_len -
                                (ei.bei_nrdn.bv_val - ndn->bv_val);
+                       eip->bei_finders++;
                        bdb_cache_entryinfo_unlock( eip );
 
                        BDB_LOG_PRINTF( bdb->bi_dbenv, NULL, "slapd Reading %s",
@@ -452,6 +455,7 @@ bdb_cache_find_ndn(
                        rc = bdb_dn2id( op, &ei.bei_nrdn, &ei, txn, &lock );
                        if (rc) {
                                bdb_cache_entryinfo_lock( eip );
+                               eip->bei_finders--;
                                bdb_cache_entry_db_unlock( bdb, &lock );
                                *res = eip;
                                return rc;
@@ -464,6 +468,7 @@ bdb_cache_find_ndn(
                        ei.bei_nrdn.bv_len = len;
                        rc = bdb_entryinfo_add_internal( bdb, &ei, &ei2 );
                        /* add_internal left eip and c_rwlock locked */
+                       eip->bei_finders--;
                        ldap_pvt_thread_rdwr_wunlock( &bdb->bi_cache.c_rwlock );
                        bdb_cache_entry_db_unlock( bdb, &lock );
                        if ( rc ) {
@@ -480,8 +485,8 @@ bdb_cache_find_ndn(
                        *res = eip;
                        return DB_NOTFOUND;
                }
-               bdb_cache_entryinfo_unlock( eip );
                bdb_cache_entryinfo_lock( ei2 );
+               bdb_cache_entryinfo_unlock( eip );
 
                eip = ei2;
 
@@ -515,7 +520,7 @@ hdb_cache_find_parent(
 {
        struct bdb_info *bdb = (struct bdb_info *) op->o_bd->be_private;
        EntryInfo ei, eip, *ei2 = NULL, *ein = NULL, *eir = NULL;
-       int rc;
+       int rc, add;
 
        ei.bei_id = id;
        ei.bei_kids = NULL;
@@ -539,36 +544,53 @@ hdb_cache_find_parent(
                ein->bei_bdb = bdb;
 #endif
                ei.bei_ckids = 0;
+               add = 1;
                
                /* This node is not fully connected yet */
                ein->bei_state |= CACHE_ENTRY_NOT_LINKED;
 
+               /* If this is the first time, save this node
+                * to be returned later.
+                */
+               if ( eir == NULL ) {
+                       eir = ein;
+                       ein->bei_finders++;
+               }
+
+again:
                /* Insert this node into the ID tree */
                ldap_pvt_thread_rdwr_wlock( &bdb->bi_cache.c_rwlock );
                if ( avl_insert( &bdb->bi_cache.c_idtree, (caddr_t)ein,
                        bdb_id_cmp, bdb_id_dup_err ) ) {
                        EntryInfo *eix = ein->bei_lrunext;
 
+                       if ( eix->bei_state & (CACHE_ENTRY_PURGED|CACHE_ENTRY_DELETED) ) {
+                               ldap_pvt_thread_rdwr_wunlock( &bdb->bi_cache.c_rwlock );
+                               ldap_pvt_thread_yield();
+                               goto again;
+                       }
+                       ldap_pvt_thread_rdwr_wunlock( &bdb->bi_cache.c_rwlock );
+
                        /* Someone else created this node just before us.
                         * Free our new copy and use the existing one.
                         */
                        bdb_cache_entryinfo_free( &bdb->bi_cache, ein );
-                       ein = eix;
-                       
-                       /* Link in any kids we've already processed */
-                       if ( ei2 ) {
-                               bdb_cache_entryinfo_lock( ein );
-                               avl_insert( &ein->bei_kids, (caddr_t)ei2,
-                                       bdb_rdn_cmp, avl_dup_error );
-                               ein->bei_ckids++;
-                               bdb_cache_entryinfo_unlock( ein );
+
+                       /* if it was the node we were looking for, just return it */
+                       if ( eir == ein ) {
+                               *res = eix;
+                               rc = 0;
+                               bdb_cache_entryinfo_lock( eix );
+                               break;
                        }
-               }
 
-               /* If this is the first time, save this node
-                * to be returned later.
-                */
-               if ( eir == NULL ) eir = ein;
+                       ein = ei2;
+                       ei2 = eix;
+                       add = 0;
+
+                       /* otherwise, link up what we have and return */
+                       goto gotparent;
+               }
 
                /* If there was a previous node, link it to this one */
                if ( ei2 ) ei2->bei_parent = ein;
@@ -577,23 +599,29 @@ hdb_cache_find_parent(
                if ( eip.bei_id ) {
                        ei2 = (EntryInfo *) avl_find( bdb->bi_cache.c_idtree,
                                        (caddr_t) &eip, bdb_id_cmp );
+                       if ( ei2 && ( ei2->bei_state & ( CACHE_ENTRY_PURGED|CACHE_ENTRY_DELETED ))) {
+                               ei2 = NULL;
+                       }
                } else {
                        ei2 = &bdb->bi_cache.c_dntree;
                }
-               bdb->bi_cache.c_eiused++;
-               if ( ei2 && ( ei2->bei_kids || !ei2->bei_id ))
+               if ( add ) {
+                       bdb->bi_cache.c_eiused++;
+                       if ( ei2 && ( ei2->bei_kids || !ei2->bei_id ))
                                bdb->bi_cache.c_leaves++;
+               }
                ldap_pvt_thread_rdwr_wunlock( &bdb->bi_cache.c_rwlock );
 
+gotparent:
                /* Got the parent, link in and we're done. */
                if ( ei2 ) {
-                       bdb_cache_entryinfo_lock( eir );
                        bdb_cache_entryinfo_lock( ei2 );
+                       bdb_cache_entryinfo_lock( eir );
                        ein->bei_parent = ei2;
 
-                       avl_insert( &ei2->bei_kids, (caddr_t)ein, bdb_rdn_cmp,
-                               avl_dup_error);
-                       ei2->bei_ckids++;
+                       if ( avl_insert( &ei2->bei_kids, (caddr_t)ein, bdb_rdn_cmp,
+                               avl_dup_error) == 0 )
+                               ei2->bei_ckids++;
 
                        /* Reset all the state info */
                        for (ein = eir; ein != ei2; ein=ein->bei_parent)
@@ -724,12 +752,18 @@ bdb_cache_lru_purge( struct bdb_info *bdb )
                 * or this node is being deleted, skip it.
                 */
                if (( elru->bei_state & ( CACHE_ENTRY_NOT_LINKED |
-                       CACHE_ENTRY_DELETED | CACHE_ENTRY_LOADING )) ||
+                       CACHE_ENTRY_DELETED | CACHE_ENTRY_LOADING |
+                       CACHE_ENTRY_ONELEVEL )) ||
                        elru->bei_finders > 0 ) {
                        bdb_cache_entryinfo_unlock( elru );
                        goto bottom;
                }
 
+               if ( bdb_cache_entryinfo_trylock( elru->bei_parent )) {
+                       bdb_cache_entryinfo_unlock( elru );
+                       goto bottom;
+               }
+
                /* entryinfo is locked */
                islocked = 1;
 
@@ -782,20 +816,13 @@ bdb_cache_lru_purge( struct bdb_info *bdb )
                }
 
 next:
-               if ( islocked )
+               if ( islocked ) {
                        bdb_cache_entryinfo_unlock( elru );
+                       bdb_cache_entryinfo_unlock( elru->bei_parent );
+               }
 
-               if ( count >= efree && eicount >= eifree ) {
-                       if ( count || ecount > bdb->bi_cache.c_cursize ) {
-                               ldap_pvt_thread_mutex_lock( &bdb->bi_cache.c_count_mutex );
-                               /* HACK: we seem to be losing track, fix up now */
-                               if ( ecount > bdb->bi_cache.c_cursize )
-                                       bdb->bi_cache.c_cursize = ecount;
-                               bdb->bi_cache.c_cursize -= count;
-                               ldap_pvt_thread_mutex_unlock( &bdb->bi_cache.c_count_mutex );
-                       }
+               if ( count >= efree && eicount >= eifree )
                        break;
-               }
 bottom:
                if ( elnext == bdb->bi_cache.c_lruhead )
                        break;
@@ -804,28 +831,19 @@ bottom:
 #endif
        }
 
+       if ( count || ecount > bdb->bi_cache.c_cursize ) {
+               ldap_pvt_thread_mutex_lock( &bdb->bi_cache.c_count_mutex );
+               /* HACK: we seem to be losing track, fix up now */
+               if ( ecount > bdb->bi_cache.c_cursize )
+                       bdb->bi_cache.c_cursize = ecount;
+               bdb->bi_cache.c_cursize -= count;
+               ldap_pvt_thread_mutex_unlock( &bdb->bi_cache.c_count_mutex );
+       }
        bdb->bi_cache.c_lruhead = elnext;
        ldap_pvt_thread_mutex_unlock( &bdb->bi_cache.c_lru_mutex );
        bdb->bi_cache.c_purging = 0;
 }
 
-EntryInfo *
-bdb_cache_find_info(
-       struct bdb_info *bdb,
-       ID id )
-{
-       EntryInfo       ei = { 0 },
-                       *ei2;
-
-       ei.bei_id = id;
-
-       ldap_pvt_thread_rdwr_rlock( &bdb->bi_cache.c_rwlock );
-       ei2 = (EntryInfo *) avl_find( bdb->bi_cache.c_idtree,
-                                       (caddr_t) &ei, bdb_id_cmp );
-       ldap_pvt_thread_rdwr_runlock( &bdb->bi_cache.c_rwlock );
-       return ei2;
-}
-
 /*
  * cache_find_id - find an entry in the cache, given id.
  * The entry is locked for Read upon return. Call with flag ID_LOCKED if
@@ -859,11 +877,12 @@ again:    ldap_pvt_thread_rdwr_rlock( &bdb->bi_cache.c_rwlock );
                if ( *eip ) {
                        /* If the lock attempt fails, the info is in use */
                        if ( bdb_cache_entryinfo_trylock( *eip )) {
+                               int del = (*eip)->bei_state & CACHE_ENTRY_DELETED;
                                ldap_pvt_thread_rdwr_runlock( &bdb->bi_cache.c_rwlock );
                                /* If this node is being deleted, treat
                                 * as if the delete has already finished
                                 */
-                               if ( (*eip)->bei_state & CACHE_ENTRY_DELETED ) {
+                               if ( del ) {
                                        return DB_NOTFOUND;
                                }
                                /* otherwise, wait for the info to free up */
@@ -920,6 +939,10 @@ again:     ldap_pvt_thread_rdwr_rlock( &bdb->bi_cache.c_rwlock );
                } else {
                        (*eip)->bei_finders++;
                        (*eip)->bei_state |= CACHE_ENTRY_REFERENCED;
+                       if ( flag & ID_NOENTRY ) {
+                               bdb_cache_entryinfo_unlock( *eip );
+                               return 0;
+                       }
                        /* Make sure only one thread tries to load the entry */
 load1:
 #ifdef SLAP_ZONE_ALLOC
@@ -961,6 +984,8 @@ load1:
                                        if ( rc == 0 ) {
                                                ep->e_private = *eip;
 #ifdef BDB_HIER
+                                               while ( (*eip)->bei_state & CACHE_ENTRY_NOT_LINKED )
+                                                       ldap_pvt_thread_yield();
                                                bdb_fix_dn( ep, 0 );
 #endif
                                                (*eip)->bei_e = ep;
@@ -1037,7 +1062,7 @@ load1:
                        bdb->bi_cache.c_leaves > bdb->bi_cache.c_eimax ) {
                        ldap_pvt_thread_mutex_lock( &bdb->bi_cache.c_count_mutex );
                        if ( !bdb->bi_cache.c_purging ) {
-                               if ( !( flag & ID_NOCACHE )) {
+                               if ( load && !( flag & ID_NOCACHE )) {
                                        bdb->bi_cache.c_cursize++;
                                        if ( bdb->bi_cache.c_cursize > bdb->bi_cache.c_maxsize ) {
                                                purge = 1;
@@ -1124,6 +1149,12 @@ bdb_cache_add(
        if ( eip->bei_dkids ) eip->bei_dkids++;
 #endif
 
+       if (eip->bei_parent) {
+               bdb_cache_entryinfo_lock( eip->bei_parent );
+               eip->bei_parent->bei_state &= ~CACHE_ENTRY_NO_GRANDKIDS;
+               bdb_cache_entryinfo_unlock( eip->bei_parent );
+       }
+
        rc = bdb_entryinfo_add_internal( bdb, &ei, &new );
        /* bdb_csn_commit can cause this when adding the database root entry */
        if ( new->bei_e ) {
@@ -1138,9 +1169,6 @@ bdb_cache_add(
        e->e_private = new;
        new->bei_state |= CACHE_ENTRY_NO_KIDS | CACHE_ENTRY_NO_GRANDKIDS;
        eip->bei_state &= ~CACHE_ENTRY_NO_KIDS;
-       if (eip->bei_parent) {
-               eip->bei_parent->bei_state &= ~CACHE_ENTRY_NO_GRANDKIDS;
-       }
        bdb_cache_entryinfo_unlock( eip );
 
        ldap_pvt_thread_rdwr_wunlock( &bdb->bi_cache.c_rwlock );
@@ -1320,8 +1348,10 @@ bdb_cache_delete(
        /* Get write lock on the data */
        rc = bdb_cache_entry_db_relock( bdb, txn, ei, 1, 0, lock );
        if ( rc ) {
+               bdb_cache_entryinfo_lock( ei );
                /* couldn't lock, undo and give up */
                ei->bei_state ^= CACHE_ENTRY_DELETED;
+               bdb_cache_entryinfo_unlock( ei );
                return rc;
        }
 
@@ -1331,7 +1361,10 @@ bdb_cache_delete(
        /* set lru mutex */
        ldap_pvt_thread_mutex_lock( &bdb->bi_cache.c_lru_mutex );
 
+       bdb_cache_entryinfo_lock( ei->bei_parent );
+       bdb_cache_entryinfo_lock( ei );
        rc = bdb_cache_delete_internal( &bdb->bi_cache, e->e_private, 1 );
+       bdb_cache_entryinfo_unlock( ei );
 
        /* free lru mutex */
        ldap_pvt_thread_mutex_unlock( &bdb->bi_cache.c_lru_mutex );
@@ -1373,11 +1406,12 @@ bdb_cache_delete_internal(
        int decr_leaf = 0;
 
        /* already freed? */
-       if ( !e->bei_parent )
+       if ( !e->bei_parent ) {
+               assert(0);
                return -1;
+       }
 
-       /* Lock the parent's kids tree */
-       bdb_cache_entryinfo_lock( e->bei_parent );
+       e->bei_state |= CACHE_ENTRY_PURGED;
 
 #ifdef BDB_HIER
        e->bei_parent->bei_ckids--;
@@ -1388,12 +1422,11 @@ bdb_cache_delete_internal(
                == NULL )
        {
                rc = -1;
+               assert(0);
        }
        if ( e->bei_parent->bei_kids )
                decr_leaf = 1;
 
-       bdb_cache_entryinfo_unlock( e->bei_parent );
-
        ldap_pvt_thread_rdwr_wlock( &cache->c_rwlock );
        /* id tree */
        if ( avl_delete( &cache->c_idtree, (caddr_t) e, bdb_id_cmp )) {
@@ -1402,8 +1435,10 @@ bdb_cache_delete_internal(
                        cache->c_leaves--;
        } else {
                rc = -1;
+               assert(0);
        }
        ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
+       bdb_cache_entryinfo_unlock( e->bei_parent );
 
        if ( rc == 0 ){
                /* lru */

diff --git a/servers/slapd/back-bdb/dn2id.c b/servers/slapd/back-bdb/dn2id.c
index f4c528fa48646e8b31dfc0f44bbe321b0765ea2f..24c82666768fb3b5b23f380a387b77a05f85ef0f 100644 (file)
--- a/servers/slapd/back-bdb/dn2id.c
+++ b/servers/slapd/back-bdb/dn2id.c
@@ -1102,7 +1102,7 @@ hdb_dn2idl_internal(
                cx->rc = cx->dbc->c_close( cx->dbc );
 done_one:
                bdb_cache_entryinfo_lock( cx->ei );
-               cx->ei->bei_state ^= CACHE_ENTRY_ONELEVEL;
+               cx->ei->bei_state &= ~CACHE_ENTRY_ONELEVEL;
                bdb_cache_entryinfo_unlock( cx->ei );
                if ( cx->rc )
                        return cx->rc;
@@ -1151,15 +1151,23 @@ gotit:
                                for ( cx->id = bdb_idl_first( save, &idcurs );
                                        cx->id != NOID;
                                        cx->id = bdb_idl_next( save, &idcurs )) {
-                                       cx->ei = bdb_cache_find_info( cx->bdb, cx->id );
+                                       EntryInfo *ei2;
+                                       cx->ei = NULL;
+                                       if ( bdb_cache_find_id( cx->op, cx->txn, cx->id, &cx->ei,
+                                               ID_NOENTRY, NULL ))
+                                               continue;
                                        if ( !cx->ei ||
                                                ( cx->ei->bei_state & CACHE_ENTRY_NO_KIDS ))
                                                continue;
 
+                                       ei2 = cx->ei;
                                        BDB_ID2DISK( cx->id, &cx->nid );
                                        hdb_dn2idl_internal( cx );
                                        if ( !BDB_IDL_IS_ZERO( cx->tmp ))
                                                nokids = 0;
+                                       bdb_cache_entryinfo_lock( ei2 );
+                                       ei2->bei_finders--;
+                                       bdb_cache_entryinfo_unlock( ei2 );
                                }
                                cx->depth--;
                                cx->op->o_tmpfree( save, cx->op->o_tmpmemctx );

diff --git a/servers/slapd/back-bdb/proto-bdb.h b/servers/slapd/back-bdb/proto-bdb.h
index d26184d20c670c26aa38a37b48c622ce321292f7..caf9633e92657b846f41bad64237655a83973e0b 100644 (file)
--- a/servers/slapd/back-bdb/proto-bdb.h
+++ b/servers/slapd/back-bdb/proto-bdb.h
@@ -501,7 +501,6 @@ void bdb_unlocked_cache_return_entry_rw( struct bdb_info *bdb, Entry *e, int rw
 #define bdb_cache_delete                       BDB_SYMBOL(cache_delete)
 #define bdb_cache_delete_cleanup       BDB_SYMBOL(cache_delete_cleanup)
 #define bdb_cache_find_id                      BDB_SYMBOL(cache_find_id)
-#define bdb_cache_find_info                    BDB_SYMBOL(cache_find_info)
 #define bdb_cache_find_ndn                     BDB_SYMBOL(cache_find_ndn)
 #define bdb_cache_find_parent          BDB_SYMBOL(cache_find_parent)
 #define bdb_cache_modify                       BDB_SYMBOL(cache_modify)
@@ -544,13 +543,10 @@ int bdb_cache_find_ndn(
        struct berval   *ndn,
        EntryInfo       **res
 );
-EntryInfo * bdb_cache_find_info(
-       struct bdb_info *bdb,
-       ID id
-);
 
 #define        ID_LOCKED       1
 #define        ID_NOCACHE      2
+#define        ID_NOENTRY      4
 int bdb_cache_find_id(
        Operation *op,
        DB_TXN  *tid,

diff --git a/servers/slapd/back-bdb/search.c b/servers/slapd/back-bdb/search.c
index def485ec9ee3fd080cef8f53213aa8a36dc1c006..09faf8ebe970d9d6796c9ea12dc98863ae7fb491 100644 (file)
--- a/servers/slapd/back-bdb/search.c
+++ b/servers/slapd/back-bdb/search.c
@@ -569,10 +569,6 @@ dn2entry_retry:
 #ifdef SLAP_ZONE_ALLOC
        slap_zn_runlock(bdb->bi_cache.c_zctx, e);
 #endif
-       if ( e != e_root ) {
-               bdb_cache_return_entry_r(bdb, e, &lock);
-       }
-       e = NULL;
 
        /* select candidates */
        if ( op->oq_search.rs_scope == LDAP_SCOPE_BASE ) {
@@ -595,6 +591,11 @@ cand_retry:
                }
        }
 
+       if ( e != e_root ) {
+               bdb_cache_return_entry_r(bdb, e, &lock);
+       }
+       e = NULL;
+
        /* start cursor at beginning of candidates.
         */
        cursor = 0;