Back out giant lock code, needs more work

servers/slapd/back-ldbm/add.c

@@ -27,6 +27,7 @@ ldbm_back_add(
 	struct ldbminfo	*li = (struct ldbminfo *) be->be_private;
 	struct berval	pdn;
 	Entry		*p = NULL;
+	int			rootlock = 0;
 	int			rc;
 	ID               id = NOID;
 	const char	*text = NULL;
@@ -41,12 +42,12 @@ ldbm_back_add(
 	Debug(LDAP_DEBUG_ARGS, "==> ldbm_back_add: %s\n", e->e_dn, 0, 0);
 #endif
 
-	/* grab giant lock for writing */
-	ldap_pvt_thread_rdwr_wlock(&li->li_giant_rwlock);
+	/* nobody else can add until we lock our parent */
+	ldap_pvt_thread_mutex_lock(&li->li_add_mutex);
 
 	if ( ( rc = dn2id( be, &e->e_nname, &id ) ) || id != NOID ) {
 		/* if (rc) something bad happened to ldbm cache */
-		ldap_pvt_thread_rdwr_wunlock(&li->li_giant_rwlock);
+		ldap_pvt_thread_mutex_unlock(&li->li_add_mutex);
 		send_ldap_result( conn, op, 
 			rc ? LDAP_OPERATIONS_ERROR : LDAP_ALREADY_EXISTS,
 			NULL, NULL, NULL, NULL );
@@ -56,7 +57,7 @@ ldbm_back_add(
 	rc = entry_schema_check( be, e, NULL, &text, textbuf, textlen );
 
 	if ( rc != LDAP_SUCCESS ) {
-		ldap_pvt_thread_rdwr_wunlock(&li->li_giant_rwlock);
+		ldap_pvt_thread_mutex_unlock(&li->li_add_mutex);
 
 #ifdef NEW_LOGGING
 		LDAP_LOG(( "backend", LDAP_LEVEL_ERR,
@@ -67,6 +68,7 @@ ldbm_back_add(
 			text, 0, 0 );
 #endif
 
+
 		send_ldap_result( conn, op, rc,
 			NULL, text, NULL, NULL );
 		return( -1 );
@@ -92,6 +94,8 @@ ldbm_back_add(
 			char *matched_dn = NULL;
 			BerVarray refs;
 
+			ldap_pvt_thread_mutex_unlock(&li->li_add_mutex);
+
 			if ( matched != NULL ) {
 				matched_dn = ch_strdup( matched->e_dn );
 				refs = is_entry_referral( matched )
@@ -104,8 +108,6 @@ ldbm_back_add(
 					NULL, &e->e_name, LDAP_SCOPE_DEFAULT );
 			}
 
-			ldap_pvt_thread_rdwr_wunlock(&li->li_giant_rwlock);
-
 #ifdef NEW_LOGGING
 			LDAP_LOG(( "backend", LDAP_LEVEL_ERR,
 				"ldbm_back_add: Parent of (%s) does not exist.\n",
@@ -125,12 +127,14 @@ ldbm_back_add(
 			return -1;
 		}
 
+		/* don't need the add lock anymore */
+		ldap_pvt_thread_mutex_unlock(&li->li_add_mutex);
+
 		if ( ! access_allowed( be, conn, op, p,
 			children, NULL, ACL_WRITE ) )
 		{
 			/* free parent and writer lock */
 			cache_return_entry_w( &li->li_cache, p ); 
-			ldap_pvt_thread_rdwr_wunlock(&li->li_giant_rwlock);
 
 #ifdef NEW_LOGGING
 			LDAP_LOG(( "backend", LDAP_LEVEL_ERR,
@@ -144,6 +148,7 @@ ldbm_back_add(
 			send_ldap_result( conn, op, LDAP_INSUFFICIENT_ACCESS,
 			    NULL, "no write access to parent", NULL, NULL );
 
+
 			return -1;
 		}
 
@@ -152,7 +157,6 @@ ldbm_back_add(
 
 			/* free parent and writer lock */
 			cache_return_entry_w( &li->li_cache, p );
-			ldap_pvt_thread_rdwr_wunlock(&li->li_giant_rwlock);
 
 #ifdef NEW_LOGGING
 			LDAP_LOG(( "backend", LDAP_LEVEL_ERR,
@@ -178,7 +182,6 @@ ldbm_back_add(
 
 			/* free parent and writer lock */
 			cache_return_entry_w( &li->li_cache, p );
-			ldap_pvt_thread_rdwr_wunlock(&li->li_giant_rwlock);
 
 #ifdef NEW_LOGGING
 			LDAP_LOG(( "backend", LDAP_LEVEL_ERR,
@@ -211,7 +214,7 @@ ldbm_back_add(
 				p = NULL;
 				
 				if ( ! rc ) {
-					ldap_pvt_thread_rdwr_wunlock(&li->li_giant_rwlock);
+					ldap_pvt_thread_mutex_unlock(&li->li_add_mutex);
 
 #ifdef NEW_LOGGING
 					LDAP_LOG(( "backend", LDAP_LEVEL_ERR,
@@ -233,7 +236,7 @@ ldbm_back_add(
 				}
 
 			} else {
-				ldap_pvt_thread_rdwr_wunlock(&li->li_giant_rwlock);
+				ldap_pvt_thread_mutex_unlock(&li->li_add_mutex);
 
 #ifdef NEW_LOGGING
 				LDAP_LOG(( "backend", LDAP_LEVEL_ERR,
@@ -253,6 +256,14 @@ ldbm_back_add(
 				return -1;
 			}
 		}
+
+		/*
+		 * no parent, acquire the root write lock
+		 * and release the add lock.
+		 */
+		ldap_pvt_thread_mutex_lock(&li->li_root_mutex);
+		rootlock = 1;
+		ldap_pvt_thread_mutex_unlock(&li->li_add_mutex);
 	}
 
 	if ( next_id( be, &e->e_id ) ) {
@@ -261,16 +272,20 @@ ldbm_back_add(
 			cache_return_entry_w( &li->li_cache, p ); 
 		}
 
-		ldap_pvt_thread_rdwr_wunlock(&li->li_giant_rwlock);
+		if ( rootlock ) {
+			/* release root lock */
+			ldap_pvt_thread_mutex_unlock(&li->li_root_mutex);
+		}
 
 #ifdef NEW_LOGGING
 		LDAP_LOG(( "backend", LDAP_LEVEL_ERR,
-			"ldbm_back_add: next_id failed.\n" ));
+			   "ldbm_back_add: next_id failed.\n" ));
 #else
 		Debug( LDAP_DEBUG_ANY, "ldbm_add: next_id failed\n",
 			0, 0, 0 );
 #endif
 
+
 		send_ldap_result( conn, op, LDAP_OTHER,
 			NULL, "next_id add failed", NULL, NULL );
 
@@ -288,7 +303,10 @@ ldbm_back_add(
 			cache_return_entry_w( &li->li_cache, p ); 
 		}
 
-		ldap_pvt_thread_rdwr_wunlock(&li->li_giant_rwlock);
+		if ( rootlock ) {
+			/* release root lock */
+			ldap_pvt_thread_mutex_unlock(&li->li_root_mutex);
+		}
 
 #ifdef NEW_LOGGING
 		LDAP_LOG(( "backend", LDAP_LEVEL_ERR,
@@ -374,13 +392,16 @@ return_results:;
 		cache_return_entry_w( &li->li_cache, p ); 
 	}
 
+	if ( rootlock ) {
+		/* release root lock */
+		ldap_pvt_thread_mutex_unlock(&li->li_root_mutex);
+	}
+
 	if ( rc ) {
 		/* in case of error, writer lock is freed 
 		 * and entry's private data is destroyed */
 		cache_return_entry_w( &li->li_cache, e );
 	}
 
-	ldap_pvt_thread_rdwr_wunlock(&li->li_giant_rwlock);
-
 	return( rc );
 }

servers/slapd/back-ldbm/back-ldbm.h

@@ -125,8 +125,10 @@ typedef struct ldbm_dbcache {
 #define MAXDBCACHE	128
 
 struct ldbminfo {
-	ldap_pvt_thread_rdwr_t		li_giant_rwlock;
 	ID			li_nextid;
+	ldap_pvt_thread_mutex_t		li_nextid_mutex;
+	ldap_pvt_thread_mutex_t		li_root_mutex;
+	ldap_pvt_thread_mutex_t		li_add_mutex;
 	int			li_mode;
 	slap_mask_t	li_defaultmask;
 	char			*li_directory;

servers/slapd/back-ldbm/bind.c

@@ -50,10 +50,8 @@ ldbm_back_bind(
 	Debug(LDAP_DEBUG_ARGS, "==> ldbm_back_bind: dn: %s\n", dn->bv_val, 0, 0);
 #endif
 
-	dn = ndn;
 
-	/* grab giant lock for reading */
-	ldap_pvt_thread_rdwr_rlock(&li->li_giant_rwlock);
+	dn = ndn;
 
 	/* get entry with reader lock */
 	if ( (e = dn2entry_r( be, dn, &matched )) == NULL ) {
@@ -74,8 +72,6 @@ ldbm_back_bind(
 				NULL, dn, LDAP_SCOPE_DEFAULT );
 		}
 
-		ldap_pvt_thread_rdwr_runlock(&li->li_giant_rwlock);
-
 		/* allow noauth binds */
 		rc = 1;
 		if ( method == LDAP_AUTH_SIMPLE ) {
@@ -267,7 +263,6 @@ ldbm_back_bind(
 return_results:;
 	/* free entry and reader lock */
 	cache_return_entry_r( &li->li_cache, e );
-	ldap_pvt_thread_rdwr_runlock(&li->li_giant_rwlock);
 
 	/* front end with send result on success (rc==0) */
 	return( rc );

servers/slapd/back-ldbm/compare.c

@@ -33,9 +33,6 @@ ldbm_back_compare(
 	int		rc;
 	int		manageDSAit = get_manageDSAit( op );
 
-	/* grab giant lock for reading */
-	ldap_pvt_thread_rdwr_rlock(&li->li_giant_rwlock);
-
 	/* get entry with reader lock */
 	if ( (e = dn2entry_r( be, ndn, &matched )) == NULL ) {
 		char *matched_dn = NULL;
@@ -52,8 +49,6 @@ ldbm_back_compare(
 				NULL, dn, LDAP_SCOPE_DEFAULT );
 		}
 
-		ldap_pvt_thread_rdwr_runlock(&li->li_giant_rwlock);
-
 		send_ldap_result( conn, op, LDAP_REFERRAL,
 			matched_dn, NULL, refs, NULL );
 
@@ -120,6 +115,5 @@ ldbm_back_compare(
 
 return_results:;
 	cache_return_entry_r( &li->li_cache, e );
-	ldap_pvt_thread_rdwr_runlock(&li->li_giant_rwlock);
 	return( rc );
 }

servers/slapd/back-ldbm/delete.c

@@ -29,6 +29,7 @@ ldbm_back_delete(
 	Entry	*matched;
 	struct berval	pdn;
 	Entry	*e, *p = NULL;
+	int rootlock = 0;
 	int	rc = -1;
 	int		manageDSAit = get_manageDSAit( op );
 	AttributeDescription *children = slap_schema.si_ad_children;
@@ -40,9 +41,6 @@ ldbm_back_delete(
 	Debug(LDAP_DEBUG_ARGS, "==> ldbm_back_delete: %s\n", dn->bv_val, 0, 0);
 #endif
 
-	/* grab giant lock for writing */
-	ldap_pvt_thread_rdwr_wlock(&li->li_giant_rwlock);
-
 	/* get entry with writer lock */
 	if ( (e = dn2entry_w( be, ndn, &matched )) == NULL ) {
 		char *matched_dn = NULL;
@@ -68,8 +66,6 @@ ldbm_back_delete(
 				NULL, dn, LDAP_SCOPE_DEFAULT );
 		}
 
-		ldap_pvt_thread_rdwr_wunlock(&li->li_giant_rwlock);
-
 		send_ldap_result( conn, op, LDAP_REFERRAL,
 			matched_dn, NULL, refs, NULL );
 
@@ -200,6 +196,9 @@ ldbm_back_delete(
 				goto return_results;
 			}
 		}
+
+		ldap_pvt_thread_mutex_lock(&li->li_root_mutex);
+		rootlock = 1;
 	}
 
 	/* delete from dn2id mapping */
@@ -249,10 +248,13 @@ return_results:;
 		cache_return_entry_w( &li->li_cache, p );
 	}
 
+	if ( rootlock ) {
+		/* release root lock */
+		ldap_pvt_thread_mutex_unlock(&li->li_root_mutex);
+	}
+
 	/* free entry and writer lock */
 	cache_return_entry_w( &li->li_cache, e );
 
-	ldap_pvt_thread_rdwr_wunlock(&li->li_giant_rwlock);
-
 	return rc;
 }

servers/slapd/back-ldbm/entry.c

@@ -31,8 +31,8 @@ ldbm_back_entry_release_rw(
 	if ( slapMode == SLAP_SERVER_MODE ) {
 		/* free entry and reader or writer lock */
 		cache_return_entry_rw( &li->li_cache, e, rw ); 
-
 	} else {
+		
 		entry_free( e );
 	}
 

servers/slapd/back-ldbm/init.c

@@ -172,8 +172,10 @@ ldbm_back_db_init(
 	li->li_dbshutdown = 0;
 
 	/* initialize various mutex locks & condition variables */
-	ldap_pvt_thread_rdwr_init( &li->li_giant_rwlock );
+	ldap_pvt_thread_mutex_init( &li->li_root_mutex );
+	ldap_pvt_thread_mutex_init( &li->li_add_mutex );
 	ldap_pvt_thread_mutex_init( &li->li_cache.c_mutex );
+	ldap_pvt_thread_mutex_init( &li->li_nextid_mutex );
 	ldap_pvt_thread_mutex_init( &li->li_dbcache_mutex );
 	ldap_pvt_thread_cond_init( &li->li_dbcache_cv );
 
@@ -223,8 +225,10 @@ ldbm_back_db_destroy(
 	free( li->li_directory );
 	attr_index_destroy( li->li_attrs );
 
-	ldap_pvt_thread_rdwr_destroy( &li->li_giant_rwlock );
+	ldap_pvt_thread_mutex_destroy( &li->li_root_mutex );
+	ldap_pvt_thread_mutex_destroy( &li->li_add_mutex );
 	ldap_pvt_thread_mutex_destroy( &li->li_cache.c_mutex );
+	ldap_pvt_thread_mutex_destroy( &li->li_nextid_mutex );
 	ldap_pvt_thread_mutex_destroy( &li->li_dbcache_mutex );
 	ldap_pvt_thread_cond_destroy( &li->li_dbcache_cv );
 

servers/slapd/back-ldbm/modify.c

@@ -297,8 +297,6 @@ ldbm_back_modify(
 	Debug(LDAP_DEBUG_ARGS, "ldbm_back_modify:\n", 0, 0, 0);
 #endif
 
-	/* grab giant lock for writing */
-	ldap_pvt_thread_rdwr_wlock(&li->li_giant_rwlock);
 
 	/* acquire and lock entry */
 	if ( (e = dn2entry_w( be, ndn, &matched )) == NULL ) {
@@ -316,7 +314,6 @@ ldbm_back_modify(
 				NULL, dn, LDAP_SCOPE_DEFAULT );
 		}
 
-		ldap_pvt_thread_rdwr_wunlock(&li->li_giant_rwlock);
 		send_ldap_result( conn, op, LDAP_REFERRAL,
 			matched_dn, NULL, refs, NULL );
 
@@ -373,11 +370,9 @@ ldbm_back_modify(
 		NULL, NULL, NULL, NULL );
 
 	cache_return_entry_w( &li->li_cache, e );
-	ldap_pvt_thread_rdwr_wunlock(&li->li_giant_rwlock);
 	return( 0 );
 
 error_return:;
 	cache_return_entry_w( &li->li_cache, e );
-	ldap_pvt_thread_rdwr_wunlock(&li->li_giant_rwlock);
 	return( -1 );
 }

servers/slapd/back-ldbm/modrdn.c

@@ -88,9 +88,6 @@ ldbm_back_modrdn(
 			? newSuperior->bv_val : "NULL", 0 );
 #endif
 
-	/* grab giant lock for writing */
-	ldap_pvt_thread_rdwr_wlock(&li->li_giant_rwlock);
-
 	/* get entry with writer lock */
 	if ( (e = dn2entry_w( be, ndn, &matched )) == NULL ) {
 		char* matched_dn = NULL;
@@ -107,8 +104,6 @@ ldbm_back_modrdn(
 				NULL, dn, LDAP_SCOPE_DEFAULT );
 		}
 
-		ldap_pvt_thread_rdwr_wunlock(&li->li_giant_rwlock);
-
 		send_ldap_result( conn, op, LDAP_REFERRAL,
 			matched_dn, NULL, refs, NULL );
 
@@ -267,6 +262,9 @@ ldbm_back_modrdn(
 			}
 		}
 
+		ldap_pvt_thread_mutex_lock(&li->li_root_mutex);
+		rootlock = 1;
+		
 #ifdef NEW_LOGGING
 		LDAP_LOG(( "backend", LDAP_LEVEL_INFO,
 			   "ldbm_back_modrdn: (%s) no parent, locked root.\n", e->e_dn ));
@@ -806,6 +804,11 @@ return_results:
 		cache_return_entry_w( &li->li_cache, p );
 	}
 
+	if ( rootlock ) {
+		/* release root writer lock */
+		ldap_pvt_thread_mutex_unlock(&li->li_root_mutex);
+	}
+
 	/* free entry and writer lock */
 	cache_return_entry_w( &li->li_cache, e );
 	if ( rc == MUST_DESTROY ) {
@@ -814,6 +817,5 @@ return_results:
 		 * the entry must be freed */
 		entry_free( e );
 	}
-	ldap_pvt_thread_rdwr_wunlock(&li->li_giant_rwlock);
 	return( rc );
 }

servers/slapd/back-ldbm/nextid.c

@@ -102,8 +102,11 @@ next_id_get( Backend *be, ID *idp )
 
 	*idp = NOID;
 
+	ldap_pvt_thread_mutex_lock( &li->li_nextid_mutex );
+
 	if ( li->li_nextid == NOID ) {
 		if ( ( rc = next_id_read( be, idp ) ) ) {
+			ldap_pvt_thread_mutex_unlock( &li->li_nextid_mutex );
 			return( rc );
 		}
 		li->li_nextid = *idp;
@@ -111,6 +114,7 @@ next_id_get( Backend *be, ID *idp )
 
 	*idp = li->li_nextid;
 
+	ldap_pvt_thread_mutex_unlock( &li->li_nextid_mutex );
 	return( rc );
 }
 
@@ -120,8 +124,11 @@ next_id( Backend *be, ID *idp )
 	struct ldbminfo	*li = (struct ldbminfo *) be->be_private;
 	int rc = 0;
 
+	ldap_pvt_thread_mutex_lock( &li->li_nextid_mutex );
+
 	if ( li->li_nextid == NOID ) {
 		if ( ( rc = next_id_read( be, idp ) ) ) {
+			ldap_pvt_thread_mutex_unlock( &li->li_nextid_mutex );
 			return( rc );
 		}
 		li->li_nextid = *idp;
@@ -132,5 +139,6 @@ next_id( Backend *be, ID *idp )
 		rc = -1;
 	}
 
+	ldap_pvt_thread_mutex_unlock( &li->li_nextid_mutex );
 	return( rc );
 }

servers/slapd/back-ldbm/passwd.c

@@ -31,7 +31,7 @@ ldbm_back_exop_passwd(
 )
 {
 	struct ldbminfo *li = (struct ldbminfo *) be->be_private;
-	int rc, locked=0;
+	int rc;
 	Entry *e = NULL;
 	struct berval hash = { 0, NULL };
 
@@ -108,12 +108,8 @@ ldbm_back_exop_passwd(
 		goto done;
 	}
 
-	/* grab giant lock for writing */
-	ldap_pvt_thread_rdwr_wlock(&li->li_giant_rwlock);
-
 	e = dn2entry_w( be, &ndn, NULL );
 	if( e == NULL ) {
-		ldap_pvt_thread_rdwr_wunlock(&li->li_giant_rwlock);
 		*text = "could not locate authorization entry";
 		rc = LDAP_NO_SUCH_OBJECT;
 		goto done;
@@ -177,7 +173,6 @@ ldbm_back_exop_passwd(
 done:
 	if( e != NULL ) {
 		cache_return_entry_w( &li->li_cache, e );
-		ldap_pvt_thread_rdwr_wunlock(&li->li_giant_rwlock);
 	}
 
 	if( hash.bv_val != NULL ) {

servers/slapd/back-ldbm/referral.c

@@ -38,9 +38,6 @@ ldbm_back_referrals(
 		return rc;
 	} 
 
-	/* grab giant lock for reading */
-	ldap_pvt_thread_rdwr_rlock(&li->li_giant_rwlock);
-
 	/* get entry with reader lock */
 	e = dn2entry_r( be, ndn, &matched );
 	if ( e == NULL ) {
@@ -73,8 +70,6 @@ ldbm_back_referrals(
 				NULL, dn, LDAP_SCOPE_DEFAULT );
 		}
 
-		ldap_pvt_thread_rdwr_runlock(&li->li_giant_rwlock);
-
 		if( refs != NULL ) {
 			/* send referrals */
 			send_ldap_result( conn, op, rc = LDAP_REFERRAL,
@@ -122,7 +117,5 @@ ldbm_back_referrals(
 	}
 
 	cache_return_entry_r( &li->li_cache, e );
-	ldap_pvt_thread_rdwr_runlock(&li->li_giant_rwlock);
-
 	return rc;
 }

servers/slapd/back-ldbm/search.c

@@ -64,8 +64,6 @@ ldbm_back_search(
 	Debug(LDAP_DEBUG_TRACE, "=> ldbm_back_search\n", 0, 0, 0);
 #endif
 
-	/* grab giant lock for reading */
-	ldap_pvt_thread_rdwr_rlock(&li->li_giant_rwlock);
 
 	if ( nbase->bv_len == 0 ) {
 		/* DIT root special case */
@@ -118,8 +116,6 @@ ldbm_back_search(
 				NULL, base, scope );
 		}
 
-		ldap_pvt_thread_rdwr_runlock(&li->li_giant_rwlock);
-
 		send_ldap_result( conn, op, err, matched_dn.bv_val, 
 			text, refs, NULL );
 
@@ -139,7 +135,6 @@ ldbm_back_search(
 		refs = NULL;
 
 		cache_return_entry_r( &li->li_cache, e );
-		ldap_pvt_thread_rdwr_runlock(&li->li_giant_rwlock);
 
 #ifdef NEW_LOGGING
 		LDAP_LOG(( "backend", LDAP_LEVEL_INFO,
@@ -511,8 +506,6 @@ loop_continue:
 	rc = 0;
 
 done:
-	ldap_pvt_thread_rdwr_runlock(&li->li_giant_rwlock);
-
 	if( candidates != NULL )
 		idl_free( candidates );