}
/* Atomically release and reacquire a lock */
-static int
+int
bdb_cache_entry_db_relock(
DB_ENV *env,
u_int32_t locker,
*/
if ( bdb_cache_entry_db_lock( env, locker, elru, 1, 1,
&lock ) == 0 ) {
+ /* If there's no entry, or this node is in
+ * the process of linking into the cache,
+ * skip it.
+ */
+ if ( !elru->bei_e || (elru->bei_state & CACHE_ENTRY_NOT_LINKED) ) {
+ bdb_cache_entry_db_unlock( env, &lock );
+ continue;
+ }
/* Need to lock parent to delete child */
if ( ldap_pvt_thread_mutex_trylock(
&elru->bei_parent->bei_kids_mutex )) {
{
struct bdb_info *bdb = (struct bdb_info *) op->o_bd->be_private;
EntryInfo ei, eip, *ei2 = NULL, *ein = NULL, *eir = NULL;
+ char ndn[SLAP_LDAPDN_MAXLEN];
ID parent;
int rc;
+ int addlru = 1;
ei.bei_id = id;
ei.bei_kids = NULL;
ein->bei_state = CACHE_ENTRY_NOT_LINKED;
/* Insert this node into the ID tree */
- ldap_pvt_thread_rdwr_rlock( &bdb->bi_cache.c_rwlock );
+ ldap_pvt_thread_rdwr_wlock( &bdb->bi_cache.c_rwlock );
if ( avl_insert( &bdb->bi_cache.c_idtree, (caddr_t)ein,
bdb_id_cmp, avl_dup_error ) ) {
- /* Hm, can this really happen? */
+ /* Someone else created this node just before us.
+ * Free our new copy and use the existing one.
+ */
bdb_cache_entryinfo_destroy( ein );
ein = (EntryInfo *)avl_find( bdb->bi_cache.c_idtree,
(caddr_t) &ei, bdb_id_cmp );
+
+ /* 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 );
bdb_cache_entryinfo_unlock( ein );
}
+
+ if ( !eir ) {
+ addlru = 0;
+ }
}
/* If this is the first time, save this node
/* If there was a previous node, link it to this one */
if ( ei2 ) ei2->bei_parent = ein;
+ /* Look for this node's parent */
if ( eip.bei_id ) {
ei2 = (EntryInfo *) avl_find( bdb->bi_cache.c_idtree,
(caddr_t) &eip, bdb_id_cmp );
} else {
ei2 = &bdb->bi_cache.c_dntree;
}
+ ldap_pvt_thread_rdwr_wunlock( &bdb->bi_cache.c_rwlock );
+ /* Got the parent, link in and we're done. */
if ( ei2 ) {
- ein->bei_parent = ei2;
bdb_cache_entryinfo_lock( ei2 );
+ ein->bei_parent = ei2;
avl_insert( &ei2->bei_kids, (caddr_t)ein, bdb_rdn_cmp,
avl_dup_error);
bdb_cache_entryinfo_unlock( ei2 );
- *res = eir;
bdb_cache_entryinfo_lock( eir );
- }
- ldap_pvt_thread_rdwr_runlock( &bdb->bi_cache.c_rwlock );
- if ( ei2 ) {
- /* Found a link. Reset all the state info */
+
+ /* Reset all the state info */
for (ein = eir; ein != ei2; ein=ein->bei_parent)
ein->bei_state &= ~CACHE_ENTRY_NOT_LINKED;
+ *res = eir;
break;
}
ei.bei_kids = NULL;
/* If we weren't given any info, see if we have it already cached */
if ( !*eip ) {
- ldap_pvt_thread_rdwr_rlock( &bdb->bi_cache.c_rwlock );
+again: ldap_pvt_thread_rdwr_rlock( &bdb->bi_cache.c_rwlock );
*eip = (EntryInfo *) avl_find( bdb->bi_cache.c_idtree,
(caddr_t) &ei, bdb_id_cmp );
if ( *eip ) {
- bdb_cache_entryinfo_lock( *eip );
+ /* If the lock attempt fails, the info is in use */
+ if ( ldap_pvt_thread_mutex_trylock(
+ &(*eip)->bei_kids_mutex )) {
+ 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 ) {
+ return DB_NOTFOUND;
+ }
+ /* otherwise, wait for the info to free up */
+ ldap_pvt_thread_yield();
+ goto again;
+ }
+ /* If this info isn't hooked up to its parent yet,
+ * unlock and wait for it to be fully initialized
+ */
+ if ( (*eip)->bei_state & CACHE_ENTRY_NOT_LINKED ) {
+ bdb_cache_entryinfo_unlock( *eip );
+ ldap_pvt_thread_rdwr_runlock( &bdb->bi_cache.c_rwlock );
+ ldap_pvt_thread_yield();
+ goto again;
+ }
islocked = 1;
}
ldap_pvt_thread_rdwr_runlock( &bdb->bi_cache.c_rwlock );
if ( *eip && rc == 0 ) {
if ( (*eip)->bei_state & CACHE_ENTRY_DELETED ) {
rc = DB_NOTFOUND;
- } else if (!(*eip)->bei_e ) {
- if (!ep) {
- rc = bdb_id2entry( op->o_bd, tid, id, &ep );
- }
- if ( rc == 0 ) {
- bdb_cache_entry_db_lock( bdb->bi_dbenv, locker,
- *eip, 1, 0, lock );
- ep->e_private = *eip;
+ } else {
+ bdb_cache_entry_db_lock( bdb->bi_dbenv, locker,
+ *eip, 0, 0, lock );
+ if ( !(*eip)->bei_e ) {
+ if (!ep) {
+ rc = bdb_id2entry( op->o_bd, tid, id, &ep );
+ }
+ if ( rc == 0 ) {
+ bdb_cache_entry_db_relock( bdb->bi_dbenv, locker,
+ *eip, 1, 0, lock );
+ /* Make sure no other modifier beat us to it */
+ if ( (*eip)->bei_e ) {
+ bdb_entry_return( ep );
+ ep = NULL;
+ } else {
+ ep->e_private = *eip;
#ifdef BDB_HIER
- bdb_fix_dn( ep, 0 );
+ bdb_fix_dn( ep, 0 );
#endif
- (*eip)->bei_e = ep;
- bdb_cache_entry_db_relock( bdb->bi_dbenv, locker,
- *eip, 0, 0, lock );
+ (*eip)->bei_e = ep;
+ }
+ bdb_cache_entry_db_relock( bdb->bi_dbenv, locker,
+ *eip, 0, 0, lock );
+ }
}
- } else {
#ifdef BDB_HIER
- rc = bdb_fix_dn( (*eip)->bei_e, 1 );
- if ( rc ) {
- bdb_cache_entry_db_lock( bdb->bi_dbenv,
- locker, *eip, 1, 0, lock );
- rc = bdb_fix_dn( (*eip)->bei_e, 2 );
- bdb_cache_entry_db_relock( bdb->bi_dbenv,
- locker, *eip, 0, 0, lock );
- } else {
- bdb_cache_entry_db_lock( bdb->bi_dbenv,
- locker, *eip, 0, 0, lock );
+ else {
+ rc = bdb_fix_dn( (*eip)->bei_e, 1 );
+ if ( rc ) {
+ bdb_cache_entry_db_relock( bdb->bi_dbenv,
+ locker, *eip, 1, 0, lock );
+ /* check again in case other modifier did it already */
+ if ( bdb_fix_dn( (*eip)->bei_e, 1 ) )
+ rc = bdb_fix_dn( (*eip)->bei_e, 2 );
+ bdb_cache_entry_db_relock( bdb->bi_dbenv,
+ locker, *eip, 0, 0, lock );
+ }
}
-#else
- bdb_cache_entry_db_lock( bdb->bi_dbenv, locker,
- *eip, 0, 0, lock );
#endif
}
}
/* Set this early, warn off any queriers */
ei->bei_state |= CACHE_ENTRY_DELETED;
+ /* Lock the entry's info */
+ bdb_cache_entryinfo_lock( ei );
+
/* Get write lock on the data */
bdb_cache_entry_db_relock( env, locker, ei, 1, 0, lock );
/* free cache write lock */
ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
bdb_cache_entryinfo_unlock( ei->bei_parent );
+
+ /* Leave entry info locked */
+
return( rc );
}
Entry *e
)
{
+ bdb_cache_entryinfo_unlock( BEI(e) );
bdb_cache_entryinfo_destroy( e->e_private );
e->e_private = NULL;
bdb_entry_return( e );
projects / openldap / blobdiff