X-Git-Url: https://git.sur5r.net/?a=blobdiff_plain;f=servers%2Fslapd%2Fback-bdb%2Fcache.c;h=6ca332131c9850f05e49984cdb3cd940d95717ec;hb=8f02c3f57578f6e35e89fcf73574c34108b41195;hp=db5429382ba444b25deb275f188fe92e6c8aa457;hpb=8b27523e4cfbd3f2e6f4b262821fd4736cba160c;p=openldap diff --git a/servers/slapd/back-bdb/cache.c b/servers/slapd/back-bdb/cache.c index db5429382b..6ca332131c 100644 --- a/servers/slapd/back-bdb/cache.c +++ b/servers/slapd/back-bdb/cache.c @@ -2,7 +2,7 @@ /* $OpenLDAP$ */ /* This work is part of OpenLDAP Software . * - * Copyright 2000-2007 The OpenLDAP Foundation. + * Copyright 2000-2011 The OpenLDAP Foundation. * All rights reserved. * * Redistribution and use in source and binary forms, with or without @@ -38,6 +38,7 @@ static int bdb_cache_delete_internal(Cache *cache, EntryInfo *e, int decr); #define SLAPD_UNUSED #ifdef SLAPD_UNUSED static void bdb_lru_print(Cache *cache); +static void bdb_idtree_print(Cache *cache); #endif #endif @@ -63,9 +64,10 @@ bdb_cache_entryinfo_new( Cache *cache ) if ( cache->c_eifree ) { ei = cache->c_eifree; cache->c_eifree = ei->bei_lrunext; + ei->bei_finders = 0; + ei->bei_lrunext = NULL; } ldap_pvt_thread_mutex_unlock( &cache->c_eifree_mutex ); - ei->bei_finders = 0; } if ( !ei ) { ei = ch_calloc(1, sizeof(EntryInfo)); @@ -81,10 +83,10 @@ static void bdb_cache_entryinfo_free( Cache *cache, EntryInfo *ei ) { free( ei->bei_nrdn.bv_val ); - ei->bei_nrdn.bv_val = NULL; + BER_BVZERO( &ei->bei_nrdn ); #ifdef BDB_HIER free( ei->bei_rdn.bv_val ); - ei->bei_rdn.bv_val = NULL; + BER_BVZERO( &ei->bei_rdn ); ei->bei_modrdns = 0; ei->bei_ckids = 0; ei->bei_dkids = 0; @@ -93,17 +95,26 @@ bdb_cache_entryinfo_free( Cache *cache, EntryInfo *ei ) ei->bei_kids = NULL; ei->bei_lruprev = NULL; +#if 0 ldap_pvt_thread_mutex_lock( &cache->c_eifree_mutex ); ei->bei_lrunext = cache->c_eifree; cache->c_eifree = ei; ldap_pvt_thread_mutex_unlock( &cache->c_eifree_mutex ); +#else + ldap_pvt_thread_mutex_destroy( &ei->bei_kids_mutex ); + ch_free( ei ); +#endif } #define LRU_DEL( c, e ) do { \ - if ( e == (c)->c_lruhead ) (c)->c_lruhead = e->bei_lruprev; \ - if ( e == (c)->c_lrutail ) (c)->c_lrutail = e->bei_lruprev; \ - e->bei_lrunext->bei_lruprev = e->bei_lruprev; \ - e->bei_lruprev->bei_lrunext = e->bei_lrunext; \ + if ( e == e->bei_lruprev ) { \ + (c)->c_lruhead = (c)->c_lrutail = NULL; \ + } else { \ + if ( e == (c)->c_lruhead ) (c)->c_lruhead = e->bei_lruprev; \ + if ( e == (c)->c_lrutail ) (c)->c_lrutail = e->bei_lruprev; \ + e->bei_lrunext->bei_lruprev = e->bei_lruprev; \ + e->bei_lruprev->bei_lrunext = e->bei_lrunext; \ + } \ e->bei_lruprev = NULL; \ } while ( 0 ) @@ -119,13 +130,13 @@ static void bdb_cache_lru_link( struct bdb_info *bdb, EntryInfo *ei ) { + /* Already linked, ignore */ + if ( ei->bei_lruprev ) + return; + /* Insert into circular LRU list */ ldap_pvt_thread_mutex_lock( &bdb->bi_cache.c_lru_mutex ); - /* Still linked, remove */ - if ( ei->bei_lruprev ) { - LRU_DEL( &bdb->bi_cache, ei ); - } ei->bei_lruprev = bdb->bi_cache.c_lrutail; if ( bdb->bi_cache.c_lrutail ) { ei->bei_lrunext = bdb->bi_cache.c_lrutail->bei_lrunext; @@ -159,7 +170,7 @@ bdb_cache_lru_link( struct bdb_info *bdb, EntryInfo *ei ) int bdb_cache_entry_db_relock( struct bdb_info *bdb, - u_int32_t locker, + DB_TXN *txn, EntryInfo *ei, int rw, int tryOnly, @@ -174,6 +185,7 @@ bdb_cache_entry_db_relock( if ( !lock ) return 0; + DBTzero( &lockobj ); lockobj.data = &ei->bei_id; lockobj.size = sizeof(ei->bei_id) + 1; @@ -183,7 +195,7 @@ bdb_cache_entry_db_relock( list[1].lock = *lock; list[1].mode = rw ? DB_LOCK_WRITE : DB_LOCK_READ; list[1].obj = &lockobj; - rc = bdb->bi_dbenv->lock_vec(bdb->bi_dbenv, locker, tryOnly ? DB_LOCK_NOWAIT : 0, + rc = bdb->bi_dbenv->lock_vec(bdb->bi_dbenv, TXN_ID(txn), tryOnly ? DB_LOCK_NOWAIT : 0, list, 2, NULL ); if (rc && !tryOnly) { @@ -198,7 +210,7 @@ bdb_cache_entry_db_relock( } static int -bdb_cache_entry_db_lock( struct bdb_info *bdb, u_int32_t locker, EntryInfo *ei, +bdb_cache_entry_db_lock( struct bdb_info *bdb, DB_TXN *txn, EntryInfo *ei, int rw, int tryOnly, DB_LOCK *lock ) { #ifdef NO_DB_LOCK @@ -215,10 +227,11 @@ bdb_cache_entry_db_lock( struct bdb_info *bdb, u_int32_t locker, EntryInfo *ei, else db_rw = DB_LOCK_READ; + DBTzero( &lockobj ); lockobj.data = &ei->bei_id; lockobj.size = sizeof(ei->bei_id) + 1; - rc = LOCK_GET(bdb->bi_dbenv, locker, tryOnly ? DB_LOCK_NOWAIT : 0, + rc = LOCK_GET(bdb->bi_dbenv, TXN_ID(txn), tryOnly ? DB_LOCK_NOWAIT : 0, &lockobj, db_rw, lock); if (rc && !tryOnly) { Debug( LDAP_DEBUG_TRACE, @@ -244,6 +257,40 @@ bdb_cache_entry_db_unlock ( struct bdb_info *bdb, DB_LOCK *lock ) #endif } +void +bdb_cache_return_entry_rw( struct bdb_info *bdb, Entry *e, + int rw, DB_LOCK *lock ) +{ + EntryInfo *ei; + int free = 0; + + ei = e->e_private; + if ( ei && ( ei->bei_state & CACHE_ENTRY_NOT_CACHED )) { + bdb_cache_entryinfo_lock( ei ); + if ( ei->bei_state & CACHE_ENTRY_NOT_CACHED ) { + /* Releasing the entry can only be done when + * we know that nobody else is using it, i.e we + * should have an entry_db writelock. But the + * flag is only set by the thread that loads the + * entry, and only if no other threads has found + * it while it was working. All other threads + * clear the flag, which mean that we should be + * the only thread using the entry if the flag + * is set here. + */ + ei->bei_e = NULL; + ei->bei_state ^= CACHE_ENTRY_NOT_CACHED; + free = 1; + } + bdb_cache_entryinfo_unlock( ei ); + } + bdb_cache_entry_db_unlock( bdb, lock ); + if ( free ) { + e->e_private = NULL; + bdb_entry_return( e ); + } +} + static int bdb_cache_entryinfo_destroy( EntryInfo *e ) { @@ -298,8 +345,8 @@ bdb_entryinfo_add_internal( ei2 = bdb_cache_entryinfo_new( &bdb->bi_cache ); - ldap_pvt_thread_rdwr_wlock( &bdb->bi_cache.c_rwlock ); bdb_cache_entryinfo_lock( ei->bei_parent ); + ldap_pvt_thread_rdwr_wlock( &bdb->bi_cache.c_rwlock ); ei2->bei_id = ei->bei_id; ei2->bei_parent = ei->bei_parent; @@ -323,6 +370,8 @@ bdb_entryinfo_add_internal( ei->bei_rdn.bv_val = NULL; #endif } else { + int rc; + bdb->bi_cache.c_eiused++; ber_dupbv( &ei2->bei_nrdn, &ei->bei_nrdn ); @@ -332,10 +381,13 @@ bdb_entryinfo_add_internal( */ if ( ei->bei_parent->bei_kids || !ei->bei_parent->bei_id ) bdb->bi_cache.c_leaves++; - avl_insert( &ei->bei_parent->bei_kids, ei2, bdb_rdn_cmp, + rc = avl_insert( &ei->bei_parent->bei_kids, ei2, bdb_rdn_cmp, avl_dup_error ); #ifdef BDB_HIER - ei->bei_parent->bei_ckids++; + /* it's possible for hdb_cache_find_parent to beat us to it */ + if ( !rc ) { + ei->bei_parent->bei_ckids++; + } #endif } @@ -390,6 +442,7 @@ bdb_cache_find_ndn( ei.bei_parent = eip; ei2 = (EntryInfo *)avl_find( eip->bei_kids, &ei, bdb_rdn_cmp ); if ( !ei2 ) { + DBC *cursor; int len = ei.bei_nrdn.bv_len; if ( BER_BVISEMPTY( ndn )) { @@ -399,28 +452,43 @@ bdb_cache_find_ndn( ei.bei_nrdn.bv_len = ndn->bv_len - (ei.bei_nrdn.bv_val - ndn->bv_val); + eip->bei_finders++; bdb_cache_entryinfo_unlock( eip ); - rc = bdb_dn2id( op, txn, &ei.bei_nrdn, &ei ); + BDB_LOG_PRINTF( bdb->bi_dbenv, NULL, "slapd Reading %s", + ei.bei_nrdn.bv_val ); + + cursor = NULL; + rc = bdb_dn2id( op, &ei.bei_nrdn, &ei, txn, &cursor ); if (rc) { bdb_cache_entryinfo_lock( eip ); + eip->bei_finders--; + if ( cursor ) cursor->c_close( cursor ); *res = eip; return rc; } + BDB_LOG_PRINTF( bdb->bi_dbenv, NULL, "slapd Read got %s(%d)", + ei.bei_nrdn.bv_val, ei.bei_id ); + /* DN exists but needs to be added to cache */ ei.bei_nrdn.bv_len = len; rc = bdb_entryinfo_add_internal( bdb, &ei, &ei2 ); /* add_internal left eip and c_rwlock locked */ + eip->bei_finders--; ldap_pvt_thread_rdwr_wunlock( &bdb->bi_cache.c_rwlock ); + if ( cursor ) cursor->c_close( cursor ); if ( rc ) { *res = eip; return rc; } - } else if ( ei2->bei_state & CACHE_ENTRY_DELETED ) { + } + bdb_cache_entryinfo_lock( ei2 ); + if ( ei2->bei_state & CACHE_ENTRY_DELETED ) { /* In the midst of deleting? Give it a chance to * complete. */ + bdb_cache_entryinfo_unlock( ei2 ); bdb_cache_entryinfo_unlock( eip ); ldap_pvt_thread_yield(); bdb_cache_entryinfo_lock( eip ); @@ -428,7 +496,6 @@ bdb_cache_find_ndn( return DB_NOTFOUND; } bdb_cache_entryinfo_unlock( eip ); - bdb_cache_entryinfo_lock( ei2 ); eip = ei2; @@ -456,21 +523,20 @@ bdb_cache_find_ndn( int hdb_cache_find_parent( Operation *op, - DB_TXN *txn, - u_int32_t locker, + DB_TXN *txn, ID id, EntryInfo **res ) { struct bdb_info *bdb = (struct bdb_info *) op->o_bd->be_private; EntryInfo ei, eip, *ei2 = NULL, *ein = NULL, *eir = NULL; - int rc; + int rc, add; ei.bei_id = id; ei.bei_kids = NULL; ei.bei_ckids = 0; for (;;) { - rc = hdb_dn2id_parent( op, txn, locker, &ei, &eip.bei_id ); + rc = hdb_dn2id_parent( op, txn, &ei, &eip.bei_id ); if ( rc ) break; /* Save the previous node, if any */ @@ -487,67 +553,92 @@ hdb_cache_find_parent( ein->bei_bdb = bdb; #endif ei.bei_ckids = 0; + add = 1; /* This node is not fully connected yet */ ein->bei_state |= CACHE_ENTRY_NOT_LINKED; + /* If this is the first time, save this node + * to be returned later. + */ + if ( eir == NULL ) { + eir = ein; + ein->bei_finders++; + } + +again: /* Insert this node into the ID tree */ ldap_pvt_thread_rdwr_wlock( &bdb->bi_cache.c_rwlock ); if ( avl_insert( &bdb->bi_cache.c_idtree, (caddr_t)ein, bdb_id_cmp, bdb_id_dup_err ) ) { EntryInfo *eix = ein->bei_lrunext; + if ( bdb_cache_entryinfo_trylock( eix )) { + ldap_pvt_thread_rdwr_wunlock( &bdb->bi_cache.c_rwlock ); + ldap_pvt_thread_yield(); + goto again; + } + ldap_pvt_thread_rdwr_wunlock( &bdb->bi_cache.c_rwlock ); + /* Someone else created this node just before us. * Free our new copy and use the existing one. */ bdb_cache_entryinfo_free( &bdb->bi_cache, ein ); - ein = eix; - - /* 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 ); - ein->bei_ckids++; - bdb_cache_entryinfo_unlock( ein ); + + /* if it was the node we were looking for, just return it */ + if ( eir == ein ) { + *res = eix; + rc = 0; + break; } - } - /* If this is the first time, save this node - * to be returned later. - */ - if ( eir == NULL ) eir = ein; + ein = ei2; + ei2 = eix; + add = 0; + + /* otherwise, link up what we have and return */ + goto gotparent; + } /* If there was a previous node, link it to this one */ if ( ei2 ) ei2->bei_parent = ein; /* Look for this node's parent */ +par2: 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; } - bdb->bi_cache.c_eiused++; + if ( ei2 && bdb_cache_entryinfo_trylock( ei2 )) { + ldap_pvt_thread_rdwr_wunlock( &bdb->bi_cache.c_rwlock ); + ldap_pvt_thread_yield(); + ldap_pvt_thread_rdwr_wlock( &bdb->bi_cache.c_rwlock ); + goto par2; + } + if ( add ) + bdb->bi_cache.c_eiused++; if ( ei2 && ( ei2->bei_kids || !ei2->bei_id )) - bdb->bi_cache.c_leaves++; + bdb->bi_cache.c_leaves++; ldap_pvt_thread_rdwr_wunlock( &bdb->bi_cache.c_rwlock ); +gotparent: /* Got the parent, link in and we're done. */ if ( ei2 ) { - bdb_cache_entryinfo_lock( ei2 ); + bdb_cache_entryinfo_lock( eir ); ein->bei_parent = ei2; - avl_insert( &ei2->bei_kids, (caddr_t)ein, bdb_rdn_cmp, - avl_dup_error); - ei2->bei_ckids++; + if ( avl_insert( &ei2->bei_kids, (caddr_t)ein, bdb_rdn_cmp, + avl_dup_error) == 0 ) + ei2->bei_ckids++; /* Reset all the state info */ for (ein = eir; ein != ei2; ein=ein->bei_parent) ein->bei_state &= ~CACHE_ENTRY_NOT_LINKED; bdb_cache_entryinfo_unlock( ei2 ); - bdb_cache_entryinfo_lock( eir ); + eir->bei_finders--; *res = eir; break; @@ -606,32 +697,54 @@ bdb_cache_lru_purge( struct bdb_info *bdb ) { DB_LOCK lock, *lockp; EntryInfo *elru, *elnext = NULL; - int count, islocked, eimax; + int islocked; + ID eicount, ecount; + ID count, efree, eifree = 0; +#ifdef LDAP_DEBUG + int iter; +#endif /* Wait for the mutex; we're the only one trying to purge. */ ldap_pvt_thread_mutex_lock( &bdb->bi_cache.c_lru_mutex ); - if ( bdb->bi_cache.c_cursize <= bdb->bi_cache.c_maxsize ) { + if ( bdb->bi_cache.c_cursize > bdb->bi_cache.c_maxsize ) { + efree = bdb->bi_cache.c_cursize - bdb->bi_cache.c_maxsize; + efree += bdb->bi_cache.c_minfree; + } else { + efree = 0; + } + + /* maximum number of EntryInfo leaves to cache. In slapcat + * we always free all leaf nodes. + */ + + if ( slapMode & SLAP_TOOL_READONLY ) { + eifree = bdb->bi_cache.c_leaves; + } else if ( bdb->bi_cache.c_eimax && + bdb->bi_cache.c_leaves > bdb->bi_cache.c_eimax ) { + eifree = bdb->bi_cache.c_minfree * 10; + if ( eifree >= bdb->bi_cache.c_leaves ) + eifree /= 2; + } + + if ( !efree && !eifree ) { ldap_pvt_thread_mutex_unlock( &bdb->bi_cache.c_lru_mutex ); bdb->bi_cache.c_purging = 0; return; } - if ( bdb->bi_cache.c_locker ) { + if ( bdb->bi_cache.c_txn ) { lockp = &lock; } else { lockp = NULL; } count = 0; - - /* maximum number of EntryInfo leaves to cache. In slapcat - * we always free all leaf nodes. - */ - if ( slapMode & SLAP_TOOL_READONLY ) - eimax = 0; - else - eimax = bdb->bi_cache.c_eimax; + eicount = 0; + ecount = 0; +#ifdef LDAP_DEBUG + iter = 0; +#endif /* Look for an unused entry to remove */ for ( elru = bdb->bi_cache.c_lruhead; elru; elru = elnext ) { @@ -651,12 +764,18 @@ bdb_cache_lru_purge( struct bdb_info *bdb ) * or this node is being deleted, skip it. */ if (( elru->bei_state & ( CACHE_ENTRY_NOT_LINKED | - CACHE_ENTRY_DELETED | CACHE_ENTRY_LOADING )) || + CACHE_ENTRY_DELETED | CACHE_ENTRY_LOADING | + CACHE_ENTRY_ONELEVEL )) || elru->bei_finders > 0 ) { bdb_cache_entryinfo_unlock( elru ); goto bottom; } + if ( bdb_cache_entryinfo_trylock( elru->bei_parent )) { + bdb_cache_entryinfo_unlock( elru ); + goto bottom; + } + /* entryinfo is locked */ islocked = 1; @@ -664,18 +783,32 @@ bdb_cache_lru_purge( struct bdb_info *bdb ) * the object is idle. */ if ( bdb_cache_entry_db_lock( bdb, - bdb->bi_cache.c_locker, elru, 1, 1, lockp ) == 0 ) { + bdb->bi_cache.c_txn, elru, 1, 1, lockp ) == 0 ) { /* Free entry for this node if it's present */ if ( elru->bei_e ) { - elru->bei_e->e_private = NULL; + ecount++; + + /* the cache may have gone over the limit while we + * weren't looking, so double check. + */ + if ( !efree && ecount > bdb->bi_cache.c_maxsize ) + efree = bdb->bi_cache.c_minfree; + + if ( count < efree ) { + elru->bei_e->e_private = NULL; #ifdef SLAP_ZONE_ALLOC - bdb_entry_return( bdb, elru->bei_e, elru->bei_zseq ); + bdb_entry_return( bdb, elru->bei_e, elru->bei_zseq ); #else - bdb_entry_return( elru->bei_e ); + bdb_entry_return( elru->bei_e ); #endif - elru->bei_e = NULL; - count++; + elru->bei_e = NULL; + count++; + } else { + /* Keep this node cached, skip to next */ + bdb_cache_entry_db_unlock( bdb, lockp ); + goto next; + } } bdb_cache_entry_db_unlock( bdb, lockp ); @@ -685,53 +818,47 @@ bdb_cache_lru_purge( struct bdb_info *bdb ) if ( elru->bei_kids ) { /* Drop from list, we ignore it... */ LRU_DEL( &bdb->bi_cache, elru ); - } else if ( bdb->bi_cache.c_leaves > eimax ) { + } else if ( eicount < eifree ) { /* Too many leaf nodes, free this one */ bdb_cache_delete_internal( &bdb->bi_cache, elru, 0 ); bdb_cache_delete_cleanup( &bdb->bi_cache, elru ); islocked = 0; + eicount++; } /* Leave on list until we need to free it */ } - if ( islocked ) +next: + if ( islocked ) { bdb_cache_entryinfo_unlock( elru ); + bdb_cache_entryinfo_unlock( elru->bei_parent ); + } - if ( count >= bdb->bi_cache.c_minfree ) { - ldap_pvt_thread_mutex_lock( &bdb->bi_cache.c_count_mutex ); - bdb->bi_cache.c_cursize -= count; - ldap_pvt_thread_mutex_unlock( &bdb->bi_cache.c_count_mutex ); + if ( count >= efree && eicount >= eifree ) break; - } bottom: if ( elnext == bdb->bi_cache.c_lruhead ) break; +#ifdef LDAP_DEBUG + iter++; +#endif } + if ( count || ecount > bdb->bi_cache.c_cursize ) { + ldap_pvt_thread_mutex_lock( &bdb->bi_cache.c_count_mutex ); + /* HACK: we seem to be losing track, fix up now */ + if ( ecount > bdb->bi_cache.c_cursize ) + bdb->bi_cache.c_cursize = ecount; + bdb->bi_cache.c_cursize -= count; + ldap_pvt_thread_mutex_unlock( &bdb->bi_cache.c_count_mutex ); + } bdb->bi_cache.c_lruhead = elnext; ldap_pvt_thread_mutex_unlock( &bdb->bi_cache.c_lru_mutex ); bdb->bi_cache.c_purging = 0; } -EntryInfo * -bdb_cache_find_info( - struct bdb_info *bdb, - ID id ) -{ - EntryInfo ei = { 0 }, - *ei2; - - ei.bei_id = id; - - ldap_pvt_thread_rdwr_rlock( &bdb->bi_cache.c_rwlock ); - ei2 = (EntryInfo *) avl_find( bdb->bi_cache.c_idtree, - (caddr_t) &ei, bdb_id_cmp ); - ldap_pvt_thread_rdwr_runlock( &bdb->bi_cache.c_rwlock ); - return ei2; -} - /* * cache_find_id - find an entry in the cache, given id. - * The entry is locked for Read upon return. Call with islocked TRUE if + * The entry is locked for Read upon return. Call with flag ID_LOCKED if * the supplied *eip was already locked. */ @@ -741,8 +868,7 @@ bdb_cache_find_id( DB_TXN *tid, ID id, EntryInfo **eip, - int islocked, - u_int32_t locker, + int flag, DB_LOCK *lock ) { struct bdb_info *bdb = (struct bdb_info *) op->o_bd->be_private; @@ -763,11 +889,12 @@ again: ldap_pvt_thread_rdwr_rlock( &bdb->bi_cache.c_rwlock ); if ( *eip ) { /* If the lock attempt fails, the info is in use */ if ( bdb_cache_entryinfo_trylock( *eip )) { + int del = (*eip)->bei_state & CACHE_ENTRY_DELETED; 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 ) { + if ( del ) { return DB_NOTFOUND; } /* otherwise, wait for the info to free up */ @@ -783,7 +910,7 @@ again: ldap_pvt_thread_rdwr_rlock( &bdb->bi_cache.c_rwlock ); ldap_pvt_thread_yield(); goto again; } - islocked = 1; + flag |= ID_LOCKED; } ldap_pvt_thread_rdwr_runlock( &bdb->bi_cache.c_rwlock ); } @@ -791,11 +918,11 @@ again: ldap_pvt_thread_rdwr_rlock( &bdb->bi_cache.c_rwlock ); /* See if the ID exists in the database; add it to the cache if so */ if ( !*eip ) { #ifndef BDB_HIER - rc = bdb_id2entry( op->o_bd, tid, locker, id, &ep ); + rc = bdb_id2entry( op->o_bd, tid, id, &ep ); if ( rc == 0 ) { rc = bdb_cache_find_ndn( op, tid, &ep->e_nname, eip ); - if ( *eip ) islocked = 1; + if ( *eip ) flag |= ID_LOCKED; if ( rc ) { ep->e_private = NULL; #ifdef SLAP_ZONE_ALLOC @@ -807,18 +934,27 @@ again: ldap_pvt_thread_rdwr_rlock( &bdb->bi_cache.c_rwlock ); } } #else - rc = hdb_cache_find_parent(op, tid, locker, id, eip ); - if ( rc == 0 ) islocked = 1; + rc = hdb_cache_find_parent(op, tid, id, eip ); + if ( rc == 0 ) flag |= ID_LOCKED; #endif } /* Ok, we found the info, do we have the entry? */ if ( rc == 0 ) { + if ( !( flag & ID_LOCKED )) { + bdb_cache_entryinfo_lock( *eip ); + flag |= ID_LOCKED; + } + if ( (*eip)->bei_state & CACHE_ENTRY_DELETED ) { rc = DB_NOTFOUND; } else { (*eip)->bei_finders++; (*eip)->bei_state |= CACHE_ENTRY_REFERENCED; + if ( flag & ID_NOENTRY ) { + bdb_cache_entryinfo_unlock( *eip ); + return 0; + } /* Make sure only one thread tries to load the entry */ load1: #ifdef SLAP_ZONE_ALLOC @@ -831,36 +967,65 @@ load1: if ( !(*eip)->bei_e && !((*eip)->bei_state & CACHE_ENTRY_LOADING)) { load = 1; (*eip)->bei_state |= CACHE_ENTRY_LOADING; + flag |= ID_CHKPURGE; + } + + if ( !load ) { + /* Clear the uncached state if we are not + * loading it, i.e it is already cached or + * another thread is currently loading it. + */ + if ( (*eip)->bei_state & CACHE_ENTRY_NOT_CACHED ) { + (*eip)->bei_state ^= CACHE_ENTRY_NOT_CACHED; + flag |= ID_CHKPURGE; + } } - if ( islocked ) { + if ( flag & ID_LOCKED ) { bdb_cache_entryinfo_unlock( *eip ); - islocked = 0; + flag ^= ID_LOCKED; } - rc = bdb_cache_entry_db_lock( bdb, locker, *eip, load, 0, lock ); + rc = bdb_cache_entry_db_lock( bdb, tid, *eip, load, 0, lock ); if ( (*eip)->bei_state & CACHE_ENTRY_DELETED ) { rc = DB_NOTFOUND; bdb_cache_entry_db_unlock( bdb, lock ); + bdb_cache_entryinfo_lock( *eip ); + (*eip)->bei_finders--; + bdb_cache_entryinfo_unlock( *eip ); } else if ( rc == 0 ) { if ( load ) { if ( !ep) { - rc = bdb_id2entry( op->o_bd, tid, locker, id, &ep ); + rc = bdb_id2entry( op->o_bd, tid, id, &ep ); } if ( rc == 0 ) { ep->e_private = *eip; #ifdef BDB_HIER + while ( (*eip)->bei_state & CACHE_ENTRY_NOT_LINKED ) + ldap_pvt_thread_yield(); bdb_fix_dn( ep, 0 ); #endif + bdb_cache_entryinfo_lock( *eip ); + (*eip)->bei_e = ep; #ifdef SLAP_ZONE_ALLOC (*eip)->bei_zseq = *((ber_len_t *)ep - 2); #endif ep = NULL; + if ( flag & ID_NOCACHE ) { + /* Set the cached state only if no other thread + * found the info while we were loading the entry. + */ + if ( (*eip)->bei_finders == 1 ) { + (*eip)->bei_state |= CACHE_ENTRY_NOT_CACHED; + flag ^= ID_CHKPURGE; + } + } + bdb_cache_entryinfo_unlock( *eip ); bdb_cache_lru_link( bdb, *eip ); } if ( rc == 0 ) { /* If we succeeded, downgrade back to a readlock. */ - rc = bdb_cache_entry_db_relock( bdb, locker, + rc = bdb_cache_entry_db_relock( bdb, tid, *eip, 0, 0, lock ); } else { /* Otherwise, release the lock. */ @@ -872,7 +1037,7 @@ load1: */ bdb_cache_entry_db_unlock( bdb, lock ); bdb_cache_entryinfo_lock( *eip ); - islocked = 1; + flag |= ID_LOCKED; goto load1; #ifdef BDB_HIER } else { @@ -881,12 +1046,12 @@ load1: rc = bdb_fix_dn( (*eip)->bei_e, 1 ); if ( rc ) { bdb_cache_entry_db_relock( bdb, - locker, *eip, 1, 0, lock ); + tid, *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, - locker, *eip, 0, 0, lock ); + tid, *eip, 0, 0, lock ); } #endif } @@ -898,7 +1063,7 @@ load1: } } } - if ( islocked ) { + if ( flag & ID_LOCKED ) { bdb_cache_entryinfo_unlock( *eip ); } if ( ep ) { @@ -912,11 +1077,15 @@ load1: if ( rc == 0 ) { int purge = 0; - if ( load ) { + if (( flag & ID_CHKPURGE ) || bdb->bi_cache.c_eimax ) { ldap_pvt_thread_mutex_lock( &bdb->bi_cache.c_count_mutex ); - bdb->bi_cache.c_cursize++; - if ( bdb->bi_cache.c_cursize > bdb->bi_cache.c_maxsize && - !bdb->bi_cache.c_purging ) { + if ( flag & ID_CHKPURGE ) { + bdb->bi_cache.c_cursize++; + if ( !bdb->bi_cache.c_purging && bdb->bi_cache.c_cursize > bdb->bi_cache.c_maxsize ) { + purge = 1; + bdb->bi_cache.c_purging = 1; + } + } else if ( !bdb->bi_cache.c_purging && bdb->bi_cache.c_eimax && bdb->bi_cache.c_leaves > bdb->bi_cache.c_eimax ) { purge = 1; bdb->bi_cache.c_purging = 1; } @@ -963,7 +1132,7 @@ bdb_cache_add( EntryInfo *eip, Entry *e, struct berval *nrdn, - u_int32_t locker, + DB_TXN *txn, DB_LOCK *lock ) { EntryInfo *new, ei; @@ -977,14 +1146,16 @@ bdb_cache_add( ei.bei_nrdn = *nrdn; ei.bei_lockpad = 0; +#if 0 /* 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, locker, &ei, 0, 0, lock ); + rc = bdb_cache_entry_db_lock( bdb, txn, &ei, 0, 0, lock ); if ( rc ) { bdb_cache_entryinfo_unlock( eip ); return rc; } +#endif #ifdef BDB_HIER if ( nrdn->bv_len != e->e_nname.bv_len ) { @@ -996,6 +1167,12 @@ bdb_cache_add( if ( eip->bei_dkids ) eip->bei_dkids++; #endif + if (eip->bei_parent) { + bdb_cache_entryinfo_lock( eip->bei_parent ); + eip->bei_parent->bei_state &= ~CACHE_ENTRY_NO_GRANDKIDS; + bdb_cache_entryinfo_unlock( eip->bei_parent ); + } + rc = bdb_entryinfo_add_internal( bdb, &ei, &new ); /* bdb_csn_commit can cause this when adding the database root entry */ if ( new->bei_e ) { @@ -1010,9 +1187,6 @@ bdb_cache_add( e->e_private = new; 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; - } bdb_cache_entryinfo_unlock( eip ); ldap_pvt_thread_rdwr_wunlock( &bdb->bi_cache.c_rwlock ); @@ -1025,6 +1199,7 @@ bdb_cache_add( } ldap_pvt_thread_mutex_unlock( &bdb->bi_cache.c_count_mutex ); + new->bei_finders = 1; bdb_cache_lru_link( bdb, new ); if ( purge ) @@ -1033,18 +1208,27 @@ bdb_cache_add( return rc; } +void bdb_cache_deref( + EntryInfo *ei + ) +{ + bdb_cache_entryinfo_lock( ei ); + ei->bei_finders--; + bdb_cache_entryinfo_unlock( ei ); +} + int bdb_cache_modify( struct bdb_info *bdb, Entry *e, Attribute *newAttrs, - u_int32_t locker, + DB_TXN *txn, DB_LOCK *lock ) { EntryInfo *ei = BEI(e); int rc; /* Get write lock on data */ - rc = bdb_cache_entry_db_relock( bdb, locker, ei, 1, 0, lock ); + rc = bdb_cache_entry_db_relock( bdb, txn, ei, 1, 0, lock ); /* If we've done repeated mods on a cached entry, then e_attrs * is no longer contiguous with the entry, and must be freed. @@ -1068,7 +1252,7 @@ bdb_cache_modrdn( struct berval *nrdn, Entry *new, EntryInfo *ein, - u_int32_t locker, + DB_TXN *txn, DB_LOCK *lock ) { EntryInfo *ei = BEI(e), *pei; @@ -1078,7 +1262,7 @@ bdb_cache_modrdn( #endif /* Get write lock on data */ - rc = bdb_cache_entry_db_relock( bdb, locker, ei, 1, 0, lock ); + rc = bdb_cache_entry_db_relock( bdb, txn, ei, 1, 0, lock ); if ( rc ) return rc; /* If we've done repeated mods on a cached entry, then e_attrs @@ -1104,9 +1288,6 @@ bdb_cache_modrdn( free( ei->bei_nrdn.bv_val ); ber_dupbv( &ei->bei_nrdn, nrdn ); - if ( !pei->bei_kids ) - pei->bei_state |= CACHE_ENTRY_NO_KIDS | CACHE_ENTRY_NO_GRANDKIDS; - #ifdef BDB_HIER free( ei->bei_rdn.bv_val ); @@ -1117,8 +1298,16 @@ bdb_cache_modrdn( rdn.bv_len = ptr - rdn.bv_val; } ber_dupbv( &ei->bei_rdn, &rdn ); - pei->bei_ckids--; - if ( pei->bei_dkids ) pei->bei_dkids--; + + /* If new parent, decrement kid counts */ + if ( ein ) { + pei->bei_ckids--; + if ( pei->bei_dkids ) { + pei->bei_dkids--; + if ( pei->bei_dkids < 2 ) + pei->bei_state |= CACHE_ENTRY_NO_KIDS | CACHE_ENTRY_NO_GRANDKIDS; + } + } #endif if (!ein) { @@ -1127,27 +1316,32 @@ bdb_cache_modrdn( ei->bei_parent = ein; bdb_cache_entryinfo_unlock( pei ); bdb_cache_entryinfo_lock( ein ); - } - /* parent now has kids */ - if ( ein->bei_state & CACHE_ENTRY_NO_KIDS ) - ein->bei_state ^= CACHE_ENTRY_NO_KIDS; + /* new parent now has kids */ + if ( ein->bei_state & CACHE_ENTRY_NO_KIDS ) + ein->bei_state ^= CACHE_ENTRY_NO_KIDS; + /* grandparent has grandkids */ + if ( ein->bei_parent ) + ein->bei_parent->bei_state &= ~CACHE_ENTRY_NO_GRANDKIDS; #ifdef BDB_HIER - /* parent might now have grandkids */ - if ( ein->bei_state & CACHE_ENTRY_NO_GRANDKIDS && - !(ei->bei_state & (CACHE_ENTRY_NO_KIDS))) - ein->bei_state ^= CACHE_ENTRY_NO_GRANDKIDS; + /* parent might now have grandkids */ + if ( ein->bei_state & CACHE_ENTRY_NO_GRANDKIDS && + !(ei->bei_state & CACHE_ENTRY_NO_KIDS)) + ein->bei_state ^= CACHE_ENTRY_NO_GRANDKIDS; - { - /* Record the generation number of this change */ - ldap_pvt_thread_mutex_lock( &bdb->bi_modrdns_mutex ); - bdb->bi_modrdns++; - ei->bei_modrdns = bdb->bi_modrdns; - ldap_pvt_thread_mutex_unlock( &bdb->bi_modrdns_mutex ); + ein->bei_ckids++; + if ( ein->bei_dkids ) ein->bei_dkids++; +#endif } - ein->bei_ckids++; - if ( ein->bei_dkids ) ein->bei_dkids++; + +#ifdef BDB_HIER + /* Record the generation number of this change */ + ldap_pvt_thread_mutex_lock( &bdb->bi_modrdns_mutex ); + bdb->bi_modrdns++; + ei->bei_modrdns = bdb->bi_modrdns; + ldap_pvt_thread_mutex_unlock( &bdb->bi_modrdns_mutex ); #endif + avl_insert( &ein->bei_kids, ei, bdb_rdn_cmp, avl_dup_error ); bdb_cache_entryinfo_unlock( ein ); return rc; @@ -1163,23 +1357,42 @@ int bdb_cache_delete( struct bdb_info *bdb, Entry *e, - u_int32_t locker, + DB_TXN *txn, DB_LOCK *lock ) { EntryInfo *ei = BEI(e); - int rc; + int rc, busy = 0; assert( e->e_private != NULL ); + /* Lock the entry's info */ + bdb_cache_entryinfo_lock( ei ); + /* Set this early, warn off any queriers */ ei->bei_state |= CACHE_ENTRY_DELETED; - /* Lock the entry's info */ - bdb_cache_entryinfo_lock( ei ); + if (( ei->bei_state & ( CACHE_ENTRY_NOT_LINKED | + CACHE_ENTRY_LOADING | CACHE_ENTRY_ONELEVEL )) || + ei->bei_finders > 0 ) + busy = 1; + + bdb_cache_entryinfo_unlock( ei ); + + while ( busy ) { + ldap_pvt_thread_yield(); + busy = 0; + bdb_cache_entryinfo_lock( ei ); + if (( ei->bei_state & ( CACHE_ENTRY_NOT_LINKED | + CACHE_ENTRY_LOADING | CACHE_ENTRY_ONELEVEL )) || + ei->bei_finders > 0 ) + busy = 1; + bdb_cache_entryinfo_unlock( ei ); + } /* Get write lock on the data */ - rc = bdb_cache_entry_db_relock( bdb, locker, ei, 1, 0, lock ); + rc = bdb_cache_entry_db_relock( bdb, txn, ei, 1, 0, lock ); if ( rc ) { + bdb_cache_entryinfo_lock( ei ); /* couldn't lock, undo and give up */ ei->bei_state ^= CACHE_ENTRY_DELETED; bdb_cache_entryinfo_unlock( ei ); @@ -1192,13 +1405,14 @@ bdb_cache_delete( /* set lru mutex */ ldap_pvt_thread_mutex_lock( &bdb->bi_cache.c_lru_mutex ); + bdb_cache_entryinfo_lock( ei->bei_parent ); + bdb_cache_entryinfo_lock( ei ); rc = bdb_cache_delete_internal( &bdb->bi_cache, e->e_private, 1 ); + bdb_cache_entryinfo_unlock( ei ); /* free lru mutex */ ldap_pvt_thread_mutex_unlock( &bdb->bi_cache.c_lru_mutex ); - /* Leave entry info locked */ - return( rc ); } @@ -1207,6 +1421,11 @@ bdb_cache_delete_cleanup( Cache *cache, EntryInfo *ei ) { + /* Enter with ei locked */ + + /* already freed? */ + if ( !ei->bei_parent ) return; + if ( ei->bei_e ) { ei->bei_e->e_private = NULL; #ifdef SLAP_ZONE_ALLOC @@ -1217,8 +1436,8 @@ bdb_cache_delete_cleanup( ei->bei_e = NULL; } - bdb_cache_entryinfo_free( cache, ei ); bdb_cache_entryinfo_unlock( ei ); + bdb_cache_entryinfo_free( cache, ei ); } static int @@ -1230,8 +1449,11 @@ bdb_cache_delete_internal( int rc = 0; /* return code */ int decr_leaf = 0; - /* Lock the parent's kids tree */ - bdb_cache_entryinfo_lock( e->bei_parent ); + /* already freed? */ + if ( !e->bei_parent ) { + assert(0); + return -1; + } #ifdef BDB_HIER e->bei_parent->bei_ckids--; @@ -1242,12 +1464,11 @@ bdb_cache_delete_internal( == NULL ) { rc = -1; + assert(0); } if ( e->bei_parent->bei_kids ) decr_leaf = 1; - bdb_cache_entryinfo_unlock( e->bei_parent ); - ldap_pvt_thread_rdwr_wlock( &cache->c_rwlock ); /* id tree */ if ( avl_delete( &cache->c_idtree, (caddr_t) e, bdb_id_cmp )) { @@ -1256,8 +1477,10 @@ bdb_cache_delete_internal( cache->c_leaves--; } else { rc = -1; + assert(0); } ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock ); + bdb_cache_entryinfo_unlock( e->bei_parent ); if ( rc == 0 ){ /* lru */ @@ -1322,6 +1545,36 @@ bdb_cache_release_all( Cache *cache ) } #ifdef LDAP_DEBUG +static void +bdb_lru_count( Cache *cache ) +{ + EntryInfo *e; + int ei = 0, ent = 0, nc = 0; + + for ( e = cache->c_lrutail; ; ) { + ei++; + if ( e->bei_e ) { + ent++; + if ( e->bei_state & CACHE_ENTRY_NOT_CACHED ) + nc++; + fprintf( stderr, "ei %d entry %p dn %s\n", ei, (void *) e->bei_e, e->bei_e->e_name.bv_val ); + } + e = e->bei_lrunext; + if ( e == cache->c_lrutail ) + break; + } + fprintf( stderr, "counted %d entryInfos and %d entries, %d notcached\n", + ei, ent, nc ); + ei = 0; + for ( e = cache->c_lrutail; ; ) { + ei++; + e = e->bei_lruprev; + if ( e == cache->c_lrutail ) + break; + } + fprintf( stderr, "counted %d entryInfos (on lruprev)\n", ei ); +} + #ifdef SLAPD_UNUSED static void bdb_lru_print( Cache *cache ) @@ -1346,53 +1599,54 @@ bdb_lru_print( Cache *cache ) break; } } + +static int +bdb_entryinfo_print(void *data, void *arg) +{ + EntryInfo *e = data; + fprintf( stderr, "\t%p, %p id %ld rdn \"%s\"\n", + (void *) e, (void *) e->bei_e, e->bei_id, e->bei_nrdn.bv_val ); + return 0; +} + +static void +bdb_idtree_print(Cache *cache) +{ + avl_apply( cache->c_idtree, bdb_entryinfo_print, NULL, -1, AVL_INORDER ); +} #endif #endif -#ifdef BDB_REUSE_LOCKERS static void -bdb_locker_id_free( void *key, void *data ) +bdb_reader_free( void *key, void *data ) { - DB_ENV *env = key; - u_int32_t lockid = (long)data; - int rc; + /* DB_ENV *env = key; */ + DB_TXN *txn = data; - rc = XLOCK_ID_FREE( env, lockid ); - if ( rc == EINVAL ) { - DB_LOCKREQ lr; - Debug( LDAP_DEBUG_ANY, - "bdb_locker_id_free: %lu err %s(%d)\n", - (unsigned long) lockid, db_strerror(rc), rc ); - /* release all locks held by this locker. */ - lr.op = DB_LOCK_PUT_ALL; - lr.obj = NULL; - env->lock_vec( env, lockid, 0, &lr, 1, NULL ); - XLOCK_ID_FREE( env, lockid ); - } + if ( txn ) TXN_ABORT( txn ); } /* free up any keys used by the main thread */ void -bdb_locker_flush( DB_ENV *env ) +bdb_reader_flush( DB_ENV *env ) { void *data; void *ctx = ldap_pvt_thread_pool_context(); if ( !ldap_pvt_thread_pool_getkey( ctx, env, &data, NULL ) ) { - ldap_pvt_thread_pool_setkey( ctx, env, NULL, NULL ); - bdb_locker_id_free( env, data ); + ldap_pvt_thread_pool_setkey( ctx, env, NULL, 0, NULL, NULL ); + bdb_reader_free( env, data ); } } int -bdb_locker_id( Operation *op, DB_ENV *env, u_int32_t *locker ) +bdb_reader_get( Operation *op, DB_ENV *env, DB_TXN **txn ) { int i, rc; - u_int32_t lockid; void *data; void *ctx; - if ( !env || !locker ) return -1; + if ( !env || !txn ) return -1; /* If no op was provided, try to find the ctx anyway... */ if ( op ) { @@ -1403,31 +1657,29 @@ bdb_locker_id( Operation *op, DB_ENV *env, u_int32_t *locker ) /* Shouldn't happen unless we're single-threaded */ if ( !ctx ) { - *locker = 0; + *txn = NULL; return 0; } if ( ldap_pvt_thread_pool_getkey( ctx, env, &data, NULL ) ) { for ( i=0, rc=1; rc != 0 && i<4; i++ ) { - rc = XLOCK_ID( env, &lockid ); + rc = TXN_BEGIN( env, NULL, txn, DB_READ_COMMITTED ); if (rc) ldap_pvt_thread_yield(); } if ( rc != 0) { return rc; } - data = (void *)((long)lockid); + data = *txn; if ( ( rc = ldap_pvt_thread_pool_setkey( ctx, env, - data, bdb_locker_id_free ) ) ) { - XLOCK_ID_FREE( env, lockid ); - Debug( LDAP_DEBUG_ANY, "bdb_locker_id: err %s(%d)\n", + data, bdb_reader_free, NULL, NULL ) ) ) { + TXN_ABORT( *txn ); + Debug( LDAP_DEBUG_ANY, "bdb_reader_get: err %s(%d)\n", db_strerror(rc), rc, 0 ); return rc; } } else { - lockid = (long)data; + *txn = data; } - *locker = lockid; return 0; } -#endif /* BDB_REUSE_LOCKERS */