ComputerSurge/bind9
3
0
Fork 0
Code Pull Requests 1 Activity

Now that no_references() reacquires the node lock after deleting the node,

Browse Source 
all of its callers need to maintain a reference to the lock that doesn't
involve looking at node->locknum after no_references() was called.
This commit is contained in:
David Lawrence
2001-04-20 14:35:04 +00:00
parent 4f35dccfc2
commit a0e1f68e14
1 changed files with 24 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files

37
lib/dns/rbtdb.c
View File

@@ -15,7 +15,7 @@
* WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/* $Id: rbtdb.c,v 1.157 2001/04/18 08:06:11 tale Exp $ */
/* $Id: rbtdb.c,v 1.158 2001/04/20 14:35:04 tale Exp $ */
/*
* Principal Author: Bob Halley
@@ -892,6 +892,7 @@ closeversion(dns_db_t *db, dns_dbversion_t **versionp, isc_boolean_t commit) {
rbtdb_changed_t *changed, *next_changed;
rbtdb_serial_t serial, least_serial;
dns_rbtnode_t *rbtnode;
isc_mutex_t *lock;
REQUIRE(VALID_RBTDB(rbtdb));
version = (rbtdb_version_t *)*versionp;
@@ -1010,8 +1011,9 @@ closeversion(dns_db_t *db, dns_dbversion_t **versionp, isc_boolean_t commit) {
changed = next_changed) {
next_changed = NEXT(changed, link);
rbtnode = changed->node;
lock = &rbtdb->node_locks[rbtnode->locknum].lock;
LOCK(&rbtdb->node_locks[rbtnode->locknum].lock);
LOCK(lock);
INSIST(rbtnode->references > 0);
rbtnode->references--;
@@ -1022,7 +1024,7 @@ closeversion(dns_db_t *db, dns_dbversion_t **versionp, isc_boolean_t commit) {
no_references(rbtdb, rbtnode, least_serial,
isc_rwlocktype_none);
UNLOCK(&rbtdb->node_locks[rbtnode->locknum].lock);
UNLOCK(lock);
isc_mem_put(rbtdb->common.mctx, changed,
sizeof *changed);
@@ -1701,6 +1703,7 @@ zone_find(dns_db_t *db, dns_name_t *name, dns_dbversion_t *version,
isc_boolean_t at_zonecut = ISC_FALSE;
isc_boolean_t wild;
isc_boolean_t empty_node;
isc_mutex_t *lock;
rdatasetheader_t *header, *header_next, *found, *nxtheader;
rdatasetheader_t *foundsig, *cnamesig, *nxtsig;
rbtdb_rdatatype_t sigtype;
@@ -2102,15 +2105,16 @@ zone_find(dns_db_t *db, dns_name_t *name, dns_dbversion_t *version,
*/
if (search.need_cleanup) {
node = search.zonecut;
lock = &(search.rbtdb->node_locks[node->locknum].lock);
LOCK(&(search.rbtdb->node_locks[node->locknum].lock));
LOCK(lock);
INSIST(node->references > 0);
node->references--;
if (node->references == 0)
no_references(search.rbtdb, node, 0,
isc_rwlocktype_none);
UNLOCK(&(search.rbtdb->node_locks[node->locknum].lock));
UNLOCK(lock);
}
if (close_version)
@@ -2368,6 +2372,7 @@ cache_find(dns_db_t *db, dns_name_t *name, dns_dbversion_t *version,
rbtdb_search_t search;
isc_boolean_t cname_ok = ISC_TRUE;
isc_boolean_t empty_node;
isc_mutex_t *lock;
rdatasetheader_t *header, *header_prev, *header_next;
rdatasetheader_t *found, *nsheader;
rdatasetheader_t *foundsig, *nssig, *cnamesig;
@@ -2637,14 +2642,15 @@ cache_find(dns_db_t *db, dns_name_t *name, dns_dbversion_t *version,
*/
if (search.need_cleanup) {
node = search.zonecut;
lock = &(search.rbtdb->node_locks[node->locknum].lock);
LOCK(&(search.rbtdb->node_locks[node->locknum].lock));
LOCK(lock);
INSIST(node->references > 0);
node->references--;
if (node->references == 0)
no_references(search.rbtdb, node, 0,
isc_rwlocktype_none);
UNLOCK(&(search.rbtdb->node_locks[node->locknum].lock));
UNLOCK(lock);
}
dns_rbtnodechain_reset(&search.chain);
@@ -2812,13 +2818,15 @@ detachnode(dns_db_t *db, dns_dbnode_t **targetp) {
dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)db;
dns_rbtnode_t *node;
isc_boolean_t maybe_free = ISC_FALSE;
isc_mutex_t *lock;
REQUIRE(VALID_RBTDB(rbtdb));
REQUIRE(targetp != NULL && *targetp != NULL);
node = (dns_rbtnode_t *)(*targetp);
lock = &rbtdb->node_locks[node->locknum].lock;
LOCK(&rbtdb->node_locks[node->locknum].lock);
LOCK(lock);
INSIST(node->references > 0);
node->references--;
@@ -2829,7 +2837,7 @@ detachnode(dns_db_t *db, dns_dbnode_t **targetp) {
maybe_free = ISC_TRUE;
}
UNLOCK(&rbtdb->node_locks[node->locknum].lock);
UNLOCK(lock);
*targetp = NULL;
@@ -4608,15 +4616,16 @@ static inline void
dereference_iter_node(rbtdb_dbiterator_t *rbtdbiter) {
dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)rbtdbiter->common.db;
dns_rbtnode_t *node = rbtdbiter->node;
isc_mutex_t *lock = &rbtdb->node_locks[node->locknum].lock;
if (node == NULL)
return;
LOCK(&rbtdb->node_locks[node->locknum].lock);
LOCK(lock);
INSIST(rbtdbiter->node->references > 0);
if (--node->references == 0)
no_references(rbtdb, node, 0, rbtdbiter->tree_locked);
UNLOCK(&rbtdb->node_locks[node->locknum].lock);
UNLOCK(lock);
rbtdbiter->node = NULL;
}
@@ -4626,6 +4635,7 @@ flush_deletions(rbtdb_dbiterator_t *rbtdbiter) {
dns_rbtnode_t *node;
dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)rbtdbiter->common.db;
isc_boolean_t was_read_locked = ISC_FALSE;
isc_mutex_t *lock;
int i;
if (rbtdbiter->delete != 0) {
@@ -4650,14 +4660,15 @@ flush_deletions(rbtdb_dbiterator_t *rbtdbiter) {
for (i = 0; i < rbtdbiter->delete; i++) {
node = rbtdbiter->deletions[i];
lock = &rbtdb->node_locks[node->locknum].lock;
LOCK(&rbtdb->node_locks[node->locknum].lock);
LOCK(lock);
INSIST(node->references > 0);
node->references--;
if (node->references == 0)
no_references(rbtdb, node, 0,
rbtdbiter->tree_locked);
UNLOCK(&rbtdb->node_locks[node->locknum].lock);
UNLOCK(lock);
}
rbtdbiter->delete = 0;