From: Howard Chu <hyc@openldap.org>
Date: Sat, 30 Dec 2006 12:05:55 +0000 (+0000)
Subject: In bdb_cache_add use a readlock outside the txn to protect the entry
X-Git-Tag: OPENLDAP_REL_ENG_2_4_4ALPHA~8^2~292
X-Git-Url: https://git.sur5r.net/?a=commitdiff_plain;h=e844a6956d8b3dc1a5bffa9eec20b08c6a6fc624;p=openldap

In bdb_cache_add use a readlock outside the txn to protect the entry
until send_ldap_result completes.
---

diff --git a/servers/slapd/back-bdb/add.c b/servers/slapd/back-bdb/add.c
index 41773376f0..274c8f40df 100644
--- a/servers/slapd/back-bdb/add.c
+++ b/servers/slapd/back-bdb/add.c
@@ -35,7 +35,7 @@ bdb_add(Operation *op, SlapReply *rs )
 	DB_TXN		*ltid = NULL, *lt2;
 	struct bdb_op_info opinfo = {0};
 	int subentry;
-	u_int32_t	locker = 0;
+	u_int32_t	locker = 0, rlocker = 0;
 	DB_LOCK		lock;
 
 	int		num_retries = 0;
@@ -128,6 +128,9 @@ txnReturn:
 		goto return_results;
 	}
 
+	/* Get our thread locker ID */
+	rs->sr_err = LOCK_ID( bdb->bi_dbenv, &rlocker );
+
 	if( 0 ) {
 retry:	/* transaction retry */
 		if( p ) {
@@ -424,7 +427,8 @@ retry:	/* transaction retry */
 			nrdn = op->ora_e->e_nname;
 		}
 
-		bdb_cache_add( bdb, ei, op->ora_e, &nrdn, locker );
+		/* Use the thread locker here, outside the txn */
+		bdb_cache_add( bdb, ei, op->ora_e, &nrdn, rlocker, &lock );
 
 		if(( rs->sr_err=TXN_COMMIT( ltid, 0 )) != 0 ) {
 			rs->sr_text = "txn_commit failed";
@@ -461,27 +465,26 @@ return_results:
 	}
 	op->o_private = NULL;
 
-	if( postread_ctrl != NULL && (*postread_ctrl) != NULL ) {
-		slap_sl_free( (*postread_ctrl)->ldctl_value.bv_val, op->o_tmpmemctx );
-		slap_sl_free( *postread_ctrl, op->o_tmpmemctx );
-	}
-
 	if( rs->sr_err == LDAP_SUCCESS ) {
-		EntryInfo *ei = oe->e_private;
-
 		/* We own the entry now, and it can be purged at will
 		 * Check to make sure it's the same entry we entered with.
 		 * Possibly a callback may have mucked with it, although
 		 * in general callbacks should treat the entry as read-only.
 		 */
+		bdb_cache_return_entry_r( bdb->bi_dbenv, &bi->bi_cache, oe, &lock );
 		if ( op->ora_e == oe )
 			op->ora_e = NULL;
-		ei->bei_state ^= CACHE_ENTRY_NOT_LINKED;
 
 		if ( bdb->bi_txn_cp_kbyte ) {
 			TXN_CHECKPOINT( bdb->bi_dbenv,
 				bdb->bi_txn_cp_kbyte, bdb->bi_txn_cp_min, 0 );
 		}
 	}
+
+	if( postread_ctrl != NULL && (*postread_ctrl) != NULL ) {
+		slap_sl_free( (*postread_ctrl)->ldctl_value.bv_val, op->o_tmpmemctx );
+		slap_sl_free( *postread_ctrl, op->o_tmpmemctx );
+	}
+
 	return rs->sr_err;
 }
diff --git a/servers/slapd/back-bdb/cache.c b/servers/slapd/back-bdb/cache.c
index 0c78cd3935..7a652a6e7b 100644
--- a/servers/slapd/back-bdb/cache.c
+++ b/servers/slapd/back-bdb/cache.c
@@ -886,10 +886,10 @@ bdb_cache_add(
 	EntryInfo *eip,
 	Entry *e,
 	struct berval *nrdn,
-	u_int32_t locker )
+	u_int32_t locker,
+	DB_LOCK *lock )
 {
 	EntryInfo *new, ei;
-	DB_LOCK lock;
 	int rc;
 #ifdef BDB_HIER
 	struct berval rdn = e->e_name;
@@ -903,7 +903,7 @@ bdb_cache_add(
 	/* Lock this entry so that bdb_add can run to completion.
 	 * It can only fail if BDB has run out of lock resources.
 	 */
-	rc = bdb_cache_entry_db_lock( bdb->bi_dbenv, locker, &ei, 1, 0, &lock );
+	rc = bdb_cache_entry_db_lock( bdb->bi_dbenv, locker, &ei, 0, 0, lock );
 	if ( rc ) {
 		bdb_cache_entryinfo_unlock( eip );
 		return rc;
@@ -931,9 +931,7 @@ bdb_cache_add(
 	}
 	new->bei_e = e;
 	e->e_private = new;
-	/* Set "Not linked" status so LRU purger ignores it */
-	new->bei_state = CACHE_ENTRY_NO_KIDS | CACHE_ENTRY_NO_GRANDKIDS |
-		CACHE_ENTRY_NOT_LINKED;
+	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;
diff --git a/servers/slapd/back-bdb/proto-bdb.h b/servers/slapd/back-bdb/proto-bdb.h
index cffda2426e..98d840717d 100644
--- a/servers/slapd/back-bdb/proto-bdb.h
+++ b/servers/slapd/back-bdb/proto-bdb.h
@@ -499,7 +499,8 @@ int bdb_cache_add(
 	EntryInfo *pei,
 	Entry   *e,
 	struct berval *nrdn,
-	u_int32_t locker
+	u_int32_t locker,
+	DB_LOCK *lock
 );
 int bdb_cache_modrdn(
 	struct bdb_info *bdb,