1 /* cache.c - routines to maintain an in-core cache of entries */
4 * Copyright 1998-2002 The OpenLDAP Foundation, All Rights Reserved.
5 * COPYING RESTRICTIONS APPLY, see COPYRIGHT file
13 #include <ac/string.h>
14 #include <ac/socket.h>
20 /* BDB backend specific entry info -- visible only to the cache */
21 typedef struct bdb_entry_info {
22 ldap_pvt_thread_rdwr_t bei_rdwr; /* reader/writer lock */
25 * remaining fields require backend cache lock to access
26 * These items are specific to the BDB backend and should
29 int bei_state; /* for the cache */
30 #define CACHE_ENTRY_UNDEFINED 0
31 #define CACHE_ENTRY_CREATING 1
32 #define CACHE_ENTRY_READY 2
33 #define CACHE_ENTRY_DELETED 3
34 #define CACHE_ENTRY_COMMITTED 4
36 int bei_refcnt; /* # threads ref'ing this entry */
37 Entry *bei_lrunext; /* for cache lru list */
41 #define BEI(e) ((EntryInfo *) ((e)->e_private))
43 static int bdb_cache_delete_entry_internal(Cache *cache, Entry *e);
45 static void bdb_lru_print(Cache *cache);
50 bdb_cache_entry_rdwr_lock(Entry *e, int rw)
53 LDAP_LOG( CACHE, ENTRY,
54 "bdb_cache_entry_rdwr_lock: %s lock on ID %ld\n",
55 rw ? "w" : "r", e->e_id, 0 );
57 Debug( LDAP_DEBUG_ARGS, "entry_rdwr_%slock: ID: %ld\n",
58 rw ? "w" : "r", e->e_id, 0);
62 return ldap_pvt_thread_rdwr_wlock(&BEI(e)->bei_rdwr);
64 return ldap_pvt_thread_rdwr_rlock(&BEI(e)->bei_rdwr);
68 bdb_cache_entry_rdwr_trylock(Entry *e, int rw)
71 LDAP_LOG( CACHE, ENTRY,
72 "bdb_cache_entry_rdwr_trylock: try %s lock on ID: %ld.\n",
73 rw ? "w" : "r", e->e_id, 0 );
75 Debug( LDAP_DEBUG_ARGS, "entry_rdwr_%strylock: ID: %ld\n",
76 rw ? "w" : "r", e->e_id, 0);
80 return ldap_pvt_thread_rdwr_wtrylock(&BEI(e)->bei_rdwr);
82 return ldap_pvt_thread_rdwr_rtrylock(&BEI(e)->bei_rdwr);
86 bdb_cache_entry_rdwr_unlock(Entry *e, int rw)
89 LDAP_LOG( CACHE, ENTRY,
90 "bdb_cache_entry_rdwr_unlock: remove %s lock on ID %ld.\n",
91 rw ? "w" : "r", e->e_id, 0 );
93 Debug( LDAP_DEBUG_ARGS, "entry_rdwr_%sunlock: ID: %ld\n",
94 rw ? "w" : "r", e->e_id, 0);
98 return ldap_pvt_thread_rdwr_wunlock(&BEI(e)->bei_rdwr);
100 return ldap_pvt_thread_rdwr_runlock(&BEI(e)->bei_rdwr);
105 bdb_cache_entry_rdwr_init(Entry *e)
107 return ldap_pvt_thread_rdwr_init( &BEI(e)->bei_rdwr );
111 bdb_cache_entry_rdwr_destroy(Entry *e)
113 return ldap_pvt_thread_rdwr_destroy( &BEI(e)->bei_rdwr );
117 bdb_cache_entry_private_init( Entry *e )
119 assert( e->e_private == NULL );
121 if( e->e_private != NULL ) {
122 /* this should never happen */
126 e->e_private = ch_calloc(1, sizeof(struct bdb_entry_info));
128 if( bdb_cache_entry_rdwr_init( e ) != 0 ) {
138 bdb_cache_entry_db_lock
139 ( DB_ENV *env, u_int32_t locker, Entry *e, int rw, u_int32_t flags, DB_LOCK *lock )
149 db_rw = DB_LOCK_WRITE;
151 db_rw = DB_LOCK_READ;
153 lockobj.data = e->e_nname.bv_val;
154 lockobj.size = e->e_nname.bv_len;
155 rc = LOCK_GET(env, locker, flags | DB_LOCK_NOWAIT,
156 &lockobj, db_rw, lock);
159 LDAP_LOG( CACHE, DETAIL1,
160 "bdb_cache_entry_db_lock: entry %s, rw %d, rc %d\n",
161 e->e_nname.bv_val, rw, rc );
163 Debug( LDAP_DEBUG_TRACE,
164 "bdb_cache_entry_db_lock: entry %s, rw %d, rc %d\n",
165 e->e_nname.bv_val, rw, rc );
169 #endif /* NO_THREADS */
173 bdb_cache_entry_db_unlock
174 ( DB_ENV *env, DB_LOCK *lock )
181 rc = LOCK_PUT ( env, lock );
187 * marks an entry in CREATING state as committed, so it is really returned
188 * to the cache. Otherwise an entry in CREATING state is removed.
189 * Makes e_private be destroyed at the following cache_return_entry_w,
190 * but lets the entry untouched (owned by someone else)
193 bdb_cache_entry_commit( Entry *e )
196 assert( e->e_private );
197 assert( BEI(e)->bei_state == CACHE_ENTRY_CREATING );
198 /* assert( BEI(e)->bei_refcnt == 1 ); */
200 BEI(e)->bei_state = CACHE_ENTRY_COMMITTED;
204 bdb_cache_entry_private_destroy( Entry *e )
206 assert( e->e_private );
208 bdb_cache_entry_rdwr_destroy( e );
210 free( e->e_private );
216 bdb_unlocked_cache_return_entry_rw( Cache *cache, Entry *e, int rw )
220 int refcnt, freeit = 1;
222 /* set cache write lock */
223 ldap_pvt_thread_rdwr_wlock( &cache->c_rwlock );
225 assert( e->e_private );
228 bdb_cache_entry_rdwr_unlock(e, rw);
232 refcnt = --BEI(e)->bei_refcnt;
235 * if the entry is returned when in CREATING state, it is deleted
236 * but not freed because it may belong to someone else (do_add,
239 if ( BEI(e)->bei_state == CACHE_ENTRY_CREATING ) {
241 ldap_pvt_thread_mutex_lock( &cache->lru_mutex );
242 bdb_cache_delete_entry_internal( cache, e );
244 ldap_pvt_thread_mutex_unlock( &cache->lru_mutex );
246 /* now the entry is in DELETED state */
249 if ( BEI(e)->bei_state == CACHE_ENTRY_COMMITTED ) {
250 BEI(e)->bei_state = CACHE_ENTRY_READY;
252 /* free cache write lock */
253 ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
256 LDAP_LOG( CACHE, DETAIL1,
257 "bdb_unlocked_cache_return_entry_rw: return (%ld):%s, refcnt=%d\n",
258 id, rw ? "w" : "r", refcnt );
260 Debug( LDAP_DEBUG_TRACE,
261 "====> bdb_unlocked_cache_return_entry_%s( %ld ): created (%d)\n",
262 rw ? "w" : "r", id, refcnt );
266 } else if ( BEI(e)->bei_state == CACHE_ENTRY_DELETED ) {
268 /* free cache write lock */
269 ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
272 LDAP_LOG( CACHE, DETAIL1,
273 "bdb_unlocked_cache_return_entry_rw: %ld, delete pending (%d).\n",
276 Debug( LDAP_DEBUG_TRACE,
277 "====> bdb_unlocked_cache_return_entry_%s( %ld ): delete pending (%d)\n",
278 rw ? "w" : "r", id, refcnt );
282 bdb_cache_entry_private_destroy( e );
284 bdb_entry_return( e );
287 /* free cache write lock */
288 ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
291 LDAP_LOG( CACHE, DETAIL1,
292 "bdb_unlocked_cache_return_entry_rw: (%ld): deleted (%d)\n",
295 Debug( LDAP_DEBUG_TRACE,
296 "====> bdb_unlocked_cache_return_entry_%s( %ld ): deleted (%d)\n",
297 rw ? "w" : "r", id, refcnt );
302 /* free cache write lock */
303 ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
306 LDAP_LOG( CACHE, DETAIL1,
307 "bdb_unlocked_cache_return_entry_rw: ID %ld:%s returned (%d)\n",
308 id, rw ? "w": "r", refcnt );
310 Debug( LDAP_DEBUG_TRACE,
311 "====> bdb_unlocked_cache_return_entry_%s( %ld ): returned (%d)\n",
312 rw ? "w" : "r", id, refcnt);
318 bdb_cache_return_entry_rw
319 ( DB_ENV *env, Cache *cache, Entry *e, int rw, DB_LOCK *lock )
322 int refcnt, freeit = 1;
324 /* set cache write lock */
325 ldap_pvt_thread_rdwr_wlock( &cache->c_rwlock );
327 assert( e->e_private );
329 bdb_cache_entry_db_unlock( env, lock );
331 bdb_cache_entry_rdwr_unlock(e, rw);
335 refcnt = --BEI(e)->bei_refcnt;
338 * if the entry is returned when in CREATING state, it is deleted
339 * but not freed because it may belong to someone else (do_add,
342 if ( BEI(e)->bei_state == CACHE_ENTRY_CREATING ) {
344 ldap_pvt_thread_mutex_lock( &cache->lru_mutex );
345 bdb_cache_delete_entry_internal( cache, e );
347 ldap_pvt_thread_mutex_unlock( &cache->lru_mutex );
349 /* now the entry is in DELETED state */
352 if ( BEI(e)->bei_state == CACHE_ENTRY_COMMITTED ) {
353 BEI(e)->bei_state = CACHE_ENTRY_READY;
355 /* free cache write lock */
356 ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
359 LDAP_LOG( CACHE, DETAIL1,
360 "bdb_cache_return_entry_rw: return (%ld):%s, refcnt=%d\n",
361 id, rw ? "w" : "r", refcnt );
363 Debug( LDAP_DEBUG_TRACE,
364 "====> bdb_cache_return_entry_%s( %ld ): created (%d)\n",
365 rw ? "w" : "r", id, refcnt );
369 } else if ( BEI(e)->bei_state == CACHE_ENTRY_DELETED ) {
371 /* free cache write lock */
372 ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
375 LDAP_LOG( CACHE, DETAIL1,
376 "bdb_cache_return_entry_rw: %ld, delete pending (%d).\n",
379 Debug( LDAP_DEBUG_TRACE,
380 "====> bdb_cache_return_entry_%s( %ld ): delete pending (%d)\n",
381 rw ? "w" : "r", id, refcnt );
385 bdb_cache_entry_private_destroy( e );
387 bdb_entry_return( e );
390 /* free cache write lock */
391 ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
394 LDAP_LOG( CACHE, DETAIL1,
395 "bdb_cache_return_entry_rw: (%ld): deleted (%d)\n",
398 Debug( LDAP_DEBUG_TRACE,
399 "====> bdb_cache_return_entry_%s( %ld ): deleted (%d)\n",
400 rw ? "w" : "r", id, refcnt );
405 /* free cache write lock */
406 ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
409 LDAP_LOG( CACHE, DETAIL1,
410 "bdb_cache_return_entry_rw: ID %ld:%s returned (%d)\n",
411 id, rw ? "w": "r", refcnt );
413 Debug( LDAP_DEBUG_TRACE,
414 "====> bdb_cache_return_entry_%s( %ld ): returned (%d)\n",
415 rw ? "w" : "r", id, refcnt);
420 #define LRU_DELETE( cache, e ) do { \
421 if ( BEI(e)->bei_lruprev != NULL ) { \
422 BEI(BEI(e)->bei_lruprev)->bei_lrunext = BEI(e)->bei_lrunext; \
424 (cache)->c_lruhead = BEI(e)->bei_lrunext; \
426 if ( BEI(e)->bei_lrunext != NULL ) { \
427 BEI(BEI(e)->bei_lrunext)->bei_lruprev = BEI(e)->bei_lruprev; \
429 (cache)->c_lrutail = BEI(e)->bei_lruprev; \
433 #define LRU_ADD( cache, e ) do { \
434 BEI(e)->bei_lrunext = (cache)->c_lruhead; \
435 if ( BEI(e)->bei_lrunext != NULL ) { \
436 BEI(BEI(e)->bei_lrunext)->bei_lruprev = (e); \
438 (cache)->c_lruhead = (e); \
439 BEI(e)->bei_lruprev = NULL; \
440 if ( (cache)->c_lrutail == NULL ) { \
441 (cache)->c_lrutail = (e); \
446 * cache_add_entry_rw - create and lock an entry in the cache
447 * returns: 0 entry has been created and locked
448 * 1 entry already existed
449 * -1 something bad happened
450 * other Berkeley DB locking error code
453 bdb_cache_add_entry_rw(
466 LDAP_LOG( CACHE, ENTRY,
467 "bdb_cache_add_entry_rw: add (%s):%s to cache\n",
468 e->e_dn, rw ? "w" : "r", 0 );
470 /* set cache write lock */
471 ldap_pvt_thread_rdwr_wlock( &cache->c_rwlock );
473 assert( e->e_private == NULL );
475 if( bdb_cache_entry_private_init(e) != 0 ) {
476 /* free cache write lock */
477 ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
480 LDAP_LOG( CACHE, ERR,
481 "bdb_cache_add_entry_rw: add (%s):%ld private init failed!\n",
482 e->e_dn, e->e_id, 0 );
484 Debug( LDAP_DEBUG_ANY,
485 "====> bdb_cache_add_entry( %ld ): \"%s\": private init failed!\n",
486 e->e_id, e->e_dn, 0 );
493 if ( avl_insert( &cache->c_dntree, (caddr_t) e,
494 (AVL_CMP) entry_dn_cmp, avl_dup_error ) != 0 )
496 /* free cache write lock */
497 ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
500 LDAP_LOG( CACHE, DETAIL1,
501 "bdb_cache_add_entry: (%s):%ld already in cache.\n",
502 e->e_dn, e->e_id, 0 );
504 Debug( LDAP_DEBUG_TRACE,
505 "====> bdb_cache_add_entry( %ld ): \"%s\": already in dn cache\n",
506 e->e_id, e->e_dn, 0 );
509 bdb_cache_entry_private_destroy(e);
515 if ( avl_insert( &cache->c_idtree, (caddr_t) e,
516 (AVL_CMP) entry_id_cmp, avl_dup_error ) != 0 )
519 LDAP_LOG( CACHE, DETAIL1,
520 "bdb_cache_add_entry: (%s):%ls already in cache.\n",
521 e->e_dn, e->e_id, 0 );
523 Debug( LDAP_DEBUG_ANY,
524 "====> bdb_cache_add_entry( %ld ): \"%s\": already in id cache\n",
525 e->e_id, e->e_dn, 0 );
528 /* delete from dn tree inserted above */
529 if ( avl_delete( &cache->c_dntree, (caddr_t) e,
530 (AVL_CMP) entry_dn_cmp ) == NULL )
533 LDAP_LOG( CACHE, INFO,
534 "bdb_cache_add_entry: can't delete (%s) from cache.\n",
537 Debug( LDAP_DEBUG_ANY, "====> can't delete from dn cache\n",
542 bdb_cache_entry_private_destroy(e);
544 /* free cache write lock */
545 ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
549 rc = bdb_cache_entry_db_lock( env, locker, e, rw, 0, lock );
553 case DB_LOCK_DEADLOCK :
554 case DB_LOCK_NOTGRANTED :
555 /* undo avl changes immediately */
556 if ( avl_delete( &cache->c_idtree, (caddr_t) e,
557 (AVL_CMP) entry_id_cmp ) == NULL ) {
559 LDAP_LOG( CACHE, INFO,
560 "bdb_cache_add_entry: can't delete (%s) from cache.\n",
563 Debug( LDAP_DEBUG_ANY, "====> can't delete from id cache\n", 0, 0, 0 );
566 if ( avl_delete( &cache->c_dntree, (caddr_t) e,
567 (AVL_CMP) entry_dn_cmp ) == NULL ) {
569 LDAP_LOG( CACHE, INFO,
570 "bdb_cache_add_entry: can't delete (%s) from cache.\n",
573 Debug( LDAP_DEBUG_ANY, "====> can't delete from dn cache\n", 0, 0, 0 );
578 bdb_cache_entry_private_destroy(e);
579 ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
583 /* put the entry into 'CREATING' state */
584 /* will be marked after when entry is returned */
585 BEI(e)->bei_state = CACHE_ENTRY_CREATING;
586 BEI(e)->bei_refcnt = 1;
589 ldap_pvt_thread_mutex_lock( &cache->lru_mutex );
592 if ( ++cache->c_cursize > cache->c_maxsize ) {
594 * find the lru entry not currently in use and delete it.
595 * in case a lot of entries are in use, only look at the
596 * first 10 on the tail of the list.
599 while ( cache->c_lrutail != NULL &&
600 BEI(cache->c_lrutail)->bei_refcnt != 0 &&
603 /* move this in-use entry to the front of the q */
604 ee = cache->c_lrutail;
605 LRU_DELETE( cache, ee );
606 LRU_ADD( cache, ee );
611 * found at least one to delete - try to get back under
612 * the max cache size.
614 while ( cache->c_lrutail != NULL &&
615 BEI(cache->c_lrutail)->bei_refcnt == 0 &&
616 cache->c_cursize > cache->c_maxsize )
618 e = cache->c_lrutail;
620 /* delete from cache and lru q */
621 /* XXX do we need rc ? */
622 rc = bdb_cache_delete_entry_internal( cache, e );
623 bdb_cache_entry_private_destroy( e );
624 bdb_entry_return( e );
629 ldap_pvt_thread_mutex_unlock( &cache->lru_mutex );
630 /* free cache write lock */
631 ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
636 * cache_update_entry - update a LOCKED entry which has been deleted.
637 * returns: 0 entry has been created and locked
638 * 1 entry already existed
639 * -1 something bad happened
642 bdb_cache_update_entry(
650 /* set cache write lock */
651 ldap_pvt_thread_rdwr_wlock( &cache->c_rwlock );
653 assert( e->e_private );
655 if ( avl_insert( &cache->c_dntree, (caddr_t) e,
656 (AVL_CMP) entry_dn_cmp, avl_dup_error ) != 0 )
659 LDAP_LOG( CACHE, DETAIL1,
660 "bdb_cache_update_entry: (%s):%ld already in dn cache\n",
661 e->e_dn, e->e_id, 0 );
663 Debug( LDAP_DEBUG_TRACE,
664 "====> bdb_cache_update_entry( %ld ): \"%s\": already in dn cache\n",
665 e->e_id, e->e_dn, 0 );
668 /* free cache write lock */
669 ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
674 if ( avl_insert( &cache->c_idtree, (caddr_t) e,
675 (AVL_CMP) entry_id_cmp, avl_dup_error ) != 0 )
678 LDAP_LOG( CACHE, DETAIL1,
679 "bdb_cache_update_entry: (%s)%ld already in id cache\n",
680 e->e_dn, e->e_id, 0 );
682 Debug( LDAP_DEBUG_ANY,
683 "====> bdb_cache_update_entry( %ld ): \"%s\": already in id cache\n",
684 e->e_id, e->e_dn, 0 );
687 /* delete from dn tree inserted above */
688 if ( avl_delete( &cache->c_dntree, (caddr_t) e,
689 (AVL_CMP) entry_dn_cmp ) == NULL )
692 LDAP_LOG( CACHE, INFO,
693 "bdb_cache_update_entry: can't delete (%s)%ld from dn cache.\n",
694 e->e_dn, e->e_id, 0 );
696 Debug( LDAP_DEBUG_ANY, "====> can't delete from dn cache\n",
701 /* free cache write lock */
702 ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
707 /* put the entry into 'CREATING' state */
708 /* will be marked after when entry is returned */
709 BEI(e)->bei_state = CACHE_ENTRY_CREATING;
712 ldap_pvt_thread_mutex_lock( &cache->lru_mutex );
715 if ( ++cache->c_cursize > cache->c_maxsize ) {
717 * find the lru entry not currently in use and delete it.
718 * in case a lot of entries are in use, only look at the
719 * first 10 on the tail of the list.
722 while ( cache->c_lrutail != NULL &&
723 BEI(cache->c_lrutail)->bei_refcnt != 0 &&
726 /* move this in-use entry to the front of the q */
727 ee = cache->c_lrutail;
728 LRU_DELETE( cache, ee );
729 LRU_ADD( cache, ee );
734 * found at least one to delete - try to get back under
735 * the max cache size.
737 while ( cache->c_lrutail != NULL &&
738 BEI(cache->c_lrutail)->bei_refcnt == 0 &&
739 cache->c_cursize > cache->c_maxsize )
741 e = cache->c_lrutail;
743 /* delete from cache and lru q */
744 /* XXX do we need rc ? */
745 rc = bdb_cache_delete_entry_internal( cache, e );
746 bdb_cache_entry_private_destroy( e );
747 bdb_entry_return( e );
752 ldap_pvt_thread_mutex_unlock( &cache->lru_mutex );
753 /* free cache write lock */
754 ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
759 bdb_cache_find_entry_ndn2id(
769 /* this function is always called with normalized DN */
773 /* set cache read lock */
774 ldap_pvt_thread_rdwr_rlock( &cache->c_rwlock );
776 if ( (ep = (Entry *) avl_find( cache->c_dntree, (caddr_t) &e,
777 (AVL_CMP) entry_dn_cmp )) != NULL )
783 * ep now points to an unlocked entry
784 * we do not need to lock the entry if we only
785 * check the state, refcnt, LRU, and id.
788 assert( ep->e_private );
792 state = BEI(ep)->bei_state;
795 * entry is deleted or not fully created yet
797 if ( state != CACHE_ENTRY_READY ) {
798 assert(state != CACHE_ENTRY_UNDEFINED);
800 /* free cache read lock */
801 ldap_pvt_thread_rdwr_runlock( &cache->c_rwlock );
804 LDAP_LOG( CACHE, INFO,
805 "bdb_cache_find_entry_dn2id: (%s) %ld not ready: %d\n",
806 ndn->bv_val, id, state );
808 Debug(LDAP_DEBUG_TRACE,
809 "====> bdb_cache_find_entry_dn2id(\"%s\"): %ld (not ready) %d\n",
810 ndn->bv_val, id, state);
814 ldap_pvt_thread_yield();
818 /* free cache read lock */
819 ldap_pvt_thread_rdwr_runlock( &cache->c_rwlock );
822 ldap_pvt_thread_mutex_lock( &cache->lru_mutex );
825 LRU_DELETE( cache, ep );
826 LRU_ADD( cache, ep );
829 ldap_pvt_thread_mutex_unlock( &cache->lru_mutex );
832 LDAP_LOG( CACHE, DETAIL1,
833 "bdb_cache_find_entry_dn2id: (%s): %ld %d tries\n",
834 ndn->bv_val, id, count );
836 Debug(LDAP_DEBUG_TRACE,
837 "====> bdb_cache_find_entry_dn2id(\"%s\"): %ld (%d tries)\n",
838 ndn->bv_val, id, count);
842 /* free cache read lock */
843 ldap_pvt_thread_rdwr_runlock( &cache->c_rwlock );
852 * cache_find_entry_id - find an entry in the cache, given id
856 bdb_cache_find_entry_id(
873 /* set cache read lock */
874 ldap_pvt_thread_rdwr_rlock( &cache->c_rwlock );
876 if ( (ep = (Entry *) avl_find( cache->c_idtree, (caddr_t) &e,
877 (AVL_CMP) entry_id_cmp )) != NULL )
884 assert( ep->e_private );
887 state = BEI(ep)->bei_state;
890 * entry is deleted or not fully created yet
892 if ( state != CACHE_ENTRY_READY ) {
894 assert(state != CACHE_ENTRY_UNDEFINED);
896 /* free cache read lock */
897 ldap_pvt_thread_rdwr_runlock( &cache->c_rwlock );
900 LDAP_LOG( CACHE, INFO,
901 "bdb_cache_find_entry_id: (%ld)->%ld not ready (%d).\n",
905 Debug(LDAP_DEBUG_TRACE,
906 "====> bdb_cache_find_entry_id( %ld ): %ld (not ready) %d\n",
910 ldap_pvt_thread_yield();
914 /* acquire reader lock */
915 rc = bdb_cache_entry_db_lock ( env, locker, ep, rw, 0, lock );
918 if ( bdb_cache_entry_rdwr_trylock(ep, rw) == LDAP_PVT_THREAD_EBUSY ) {
921 if ( rc ) { /* will be changed to retry beyond threshold */
922 /* could not acquire entry lock...
923 * owner cannot free as we have the cache locked.
924 * so, unlock the cache, yield, and try again.
927 /* free cache read lock */
928 ldap_pvt_thread_rdwr_runlock( &cache->c_rwlock );
931 LDAP_LOG( CACHE, INFO,
932 "bdb_cache_find_entry_id: %ld -> %ld (busy) %d.\n",
935 Debug(LDAP_DEBUG_TRACE,
936 "====> bdb_cache_find_entry_id( %ld ): %ld (busy) %d\n",
938 Debug(LDAP_DEBUG_TRACE,
943 ldap_pvt_thread_yield();
947 /* free cache read lock */
948 ldap_pvt_thread_rdwr_runlock( &cache->c_rwlock );
950 ldap_pvt_thread_mutex_lock( &cache->lru_mutex );
952 LRU_DELETE( cache, ep );
953 LRU_ADD( cache, ep );
955 BEI(ep)->bei_refcnt++;
958 ldap_pvt_thread_mutex_unlock( &cache->lru_mutex );
961 LDAP_LOG( CACHE, DETAIL1,
962 "bdb_cache_find_entry_id: %ld -> %s found %d tries.\n",
963 ep_id, ep->e_dn, count );
965 Debug(LDAP_DEBUG_TRACE,
966 "====> bdb_cache_find_entry_id( %ld ) \"%s\" (found) (%d tries)\n",
967 ep_id, ep->e_dn, count);
974 /* free cache read lock */
975 ldap_pvt_thread_rdwr_runlock( &cache->c_rwlock );
981 * cache_delete_entry - delete the entry e from the cache. the caller
982 * should have obtained e (increasing its ref count) via a call to one
983 * of the cache_find_* routines. the caller should *not* call the
984 * cache_return_entry() routine prior to calling cache_delete_entry().
985 * it performs this function.
987 * returns: 0 e was deleted ok
988 * 1 e was not in the cache
989 * -1 something bad happened
992 bdb_cache_delete_entry(
999 /* set cache write lock */
1000 ldap_pvt_thread_rdwr_wlock( &cache->c_rwlock );
1002 assert( e->e_private );
1005 LDAP_LOG( CACHE, ENTRY,
1006 "bdb_cache_delete_entry: delete %ld.\n", e->e_id, 0, 0 );
1008 Debug( LDAP_DEBUG_TRACE, "====> bdb_cache_delete_entry( %ld )\n",
1013 ldap_pvt_thread_mutex_lock( &cache->lru_mutex );
1014 rc = bdb_cache_delete_entry_internal( cache, e );
1015 /* free lru mutex */
1016 ldap_pvt_thread_mutex_unlock( &cache->lru_mutex );
1018 /* free cache write lock */
1019 ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
1024 bdb_cache_delete_entry_internal(
1029 int rc = 0; /* return code */
1032 if ( avl_delete( &cache->c_dntree, (caddr_t) e, (AVL_CMP) entry_dn_cmp )
1039 if ( avl_delete( &cache->c_idtree, (caddr_t) e, (AVL_CMP) entry_id_cmp )
1050 LRU_DELETE( cache, e );
1054 * flag entry to be freed later by a call to cache_return_entry()
1056 BEI(e)->bei_state = CACHE_ENTRY_DELETED;
1062 bdb_cache_release_all( Cache *cache )
1067 /* set cache write lock */
1068 ldap_pvt_thread_rdwr_wlock( &cache->c_rwlock );
1070 ldap_pvt_thread_mutex_lock( &cache->lru_mutex );
1073 LDAP_LOG( CACHE, ENTRY, "bdb_cache_release_all: enter\n", 0, 0, 0 );
1075 Debug( LDAP_DEBUG_TRACE, "====> bdb_cache_release_all\n", 0, 0, 0 );
1078 while ( (e = cache->c_lrutail) != NULL && BEI(e)->bei_refcnt == 0 ) {
1079 #ifdef LDAP_RDWR_DEBUG
1080 assert(!ldap_pvt_thread_rdwr_active(&BEI(e)->bei_rdwr));
1083 /* delete from cache and lru q */
1084 /* XXX do we need rc ? */
1085 rc = bdb_cache_delete_entry_internal( cache, e );
1086 bdb_cache_entry_private_destroy( e );
1087 bdb_entry_return( e );
1090 if ( cache->c_cursize ) {
1092 LDAP_LOG( CACHE, INFO,
1093 "bdb_cache_release_all: Entry cache could not be emptied.\n", 0, 0, 0 );
1095 Debug( LDAP_DEBUG_TRACE, "Entry-cache could not be emptied\n", 0, 0, 0 );
1100 /* free lru mutex */
1101 ldap_pvt_thread_mutex_unlock( &cache->lru_mutex );
1102 /* free cache write lock */
1103 ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
1108 bdb_lru_print( Cache *cache )
1112 fprintf( stderr, "LRU queue (head to tail):\n" );
1113 for ( e = cache->c_lruhead; e != NULL; e = BEI(e)->bei_lrunext ) {
1114 fprintf( stderr, "\tdn \"%20s\" id %ld refcnt %d\n",
1115 e->e_dn, e->e_id, BEI(e)->bei_refcnt );
1117 fprintf( stderr, "LRU queue (tail to head):\n" );
1118 for ( e = cache->c_lrutail; e != NULL; e = BEI(e)->bei_lruprev ) {
1119 fprintf( stderr, "\tdn \"%20s\" id %ld refcnt %d\n",
1120 e->e_dn, e->e_id, BEI(e)->bei_refcnt );
1125 #ifdef BDB_REUSE_LOCKERS
1127 bdb_locker_id_free( void *key, void *data )
1130 int lockid = (int) data;
1132 XLOCK_ID_FREE( env, lockid );
1136 bdb_locker_id( Operation *op, DB_ENV *env, int *locker )
1141 if ( !env || !op || !locker ) return -1;
1143 /* Shouldn't happen unless we're single-threaded */
1144 if ( !op->o_threadctx ) {
1149 if ( ldap_pvt_thread_pool_getkey( op->o_threadctx, env, &data, NULL ) ) {
1150 for ( i=0, rc=1; rc != 0 && i<4; i++ ) {
1151 rc = XLOCK_ID( env, &lockid );
1152 if (rc) ldap_pvt_thread_yield();
1157 data = (void *)lockid;
1158 if ( ( rc = ldap_pvt_thread_pool_setkey( op->o_threadctx, env,
1159 data, bdb_locker_id_free ) ) ) {
1160 XLOCK_ID_FREE( env, lockid );
1162 LDAP_LOG( BACK_BDB, ERR, "bdb_locker_id: err %s(%d)\n",
1163 db_strerror(rc), rc, 0 );
1165 Debug( LDAP_DEBUG_ANY, "bdb_locker_id: err %s(%d)\n",
1166 db_strerror(rc), rc, 0 );