]> git.sur5r.net Git - openldap/blobdiff - servers/slapd/back-ldbm/dbcache.c
Happy new year
[openldap] / servers / slapd / back-ldbm / dbcache.c
index 4beef6dd6e32082585d2e8f3272ecaa2da6a3821..04c21cf3f0cc669c73bfd786980f46c74af420b9 100644 (file)
@@ -1,4 +1,18 @@
 /* ldbmcache.c - maintain a cache of open ldbm files */
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 1998-2004 The OpenLDAP Foundation.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted only as authorized by the OpenLDAP
+ * Public License.
+ *
+ * A copy of this license is available in the file LICENSE in the
+ * top-level directory of the distribution or, alternatively, at
+ * <http://www.OpenLDAP.org/license.html>.
+ */
 
 #include "portable.h"
 
 #include <ac/socket.h>
 #include <ac/string.h>
 #include <ac/time.h>
-
+#include <ac/unistd.h>
 #include <sys/stat.h>
 
-#ifdef HAVE_SYS_PARAM_H
-#include <sys/param.h>
-#endif
-
-#include "ldapconfig.h"
 #include "slap.h"
 #include "back-ldbm.h"
 
-struct dbcache *
+DBCache *
 ldbm_cache_open(
     Backend    *be,
-    char       *name,
-    char       *suffix,
+    const char *name,
+    const char *suffix,
     int                flags
 )
 {
        struct ldbminfo *li = (struct ldbminfo *) be->be_private;
-       int             i, lru;
-       time_t          oldtime, curtime;
+       int             i, lru, empty;
+       time_t          oldtime;
        char            buf[MAXPATHLEN];
-       LDBM            db;
+#ifdef HAVE_ST_BLKSIZE
        struct stat     st;
+#endif
 
-       sprintf( buf, "%s/%s%s", li->li_directory, name, suffix );
+       if (li->li_envdirok)
+               sprintf( buf, "%s%s", name, suffix );
+       else
+               sprintf( buf, "%s" LDAP_DIRSEP "%s%s",
+                       li->li_directory, name, suffix );
 
+       if( li->li_dblocking ) {
+               flags |= LDBM_LOCKING;
+       } else {
+               flags |= LDBM_NOLOCKING;
+       }
+       
+       if( li->li_dbwritesync ) {
+               flags |= LDBM_SYNC;
+       } else {
+               flags |= LDBM_NOSYNC;
+       }
+       
+#ifdef NEW_LOGGING
+       LDAP_LOG( CACHE, ENTRY, 
+               "ldbm_cache_open: \"%s\", %d, %o\n", buf, flags, li->li_mode );
+#else
        Debug( LDAP_DEBUG_TRACE, "=> ldbm_cache_open( \"%s\", %d, %o )\n", buf,
            flags, li->li_mode );
+#endif
 
-       lru = 0;
-       pthread_mutex_lock( &currenttime_mutex );
-       curtime = currenttime;
-       pthread_mutex_unlock( &currenttime_mutex );
-       oldtime = curtime;
-
-       pthread_mutex_lock( &li->li_dbcache_mutex );
-       for ( i = 0; i < MAXDBCACHE && li->li_dbcache[i].dbc_name != NULL;
-           i++ ) {
-               /* already open - return it */
-               if ( strcmp( li->li_dbcache[i].dbc_name, buf ) == 0 ) {
-                       li->li_dbcache[i].dbc_refcnt++;
-                       Debug( LDAP_DEBUG_TRACE,
-                           "<= ldbm_cache_open (cache %d)\n", i, 0, 0 );
-                       pthread_mutex_unlock( &li->li_dbcache_mutex );
-                       return( &li->li_dbcache[i] );
-               }
 
-               /* keep track of lru db */
-               if ( li->li_dbcache[i].dbc_lastref < oldtime &&
-                   li->li_dbcache[i].dbc_refcnt == 0 ) {
-                       lru = i;
-                       oldtime = li->li_dbcache[i].dbc_lastref;
-               }
-       }
+       empty = MAXDBCACHE;
 
-       /* no empty slots, not already open - close lru and use that slot */
-       if ( i == MAXDBCACHE ) {
-               i = lru;
-               if ( li->li_dbcache[i].dbc_refcnt != 0 ) {
-                       Debug( LDAP_DEBUG_ANY,
-                           "ldbm_cache_open no unused db to close - waiting\n",
-                           0, 0, 0 );
-                       lru = -1;
-                       while ( lru == -1 ) {
-                               pthread_cond_wait( &li->li_dbcache_cv,
-                                   &li->li_dbcache_mutex );
-                               for ( i = 0; i < MAXDBCACHE; i++ ) {
-                                       if ( li->li_dbcache[i].dbc_refcnt
-                                           == 0 ) {
-                                               lru = i;
-                                               break;
-                                       }
+       ldap_pvt_thread_mutex_lock( &li->li_dbcache_mutex );
+       do {
+               lru = 0;
+               oldtime = 1;
+               for ( i = 0; i < MAXDBCACHE; i++ ) {
+                       /* see if this slot is free */
+                       if ( li->li_dbcache[i].dbc_name == NULL) {
+                               if (empty == MAXDBCACHE)
+                                       empty = i;
+                               continue;
+                       }
+
+                       if ( strcmp( li->li_dbcache[i].dbc_name, buf ) == 0 ) {
+                               /* already open - return it */
+                               if (li->li_dbcache[i].dbc_flags != flags
+                                       && li->li_dbcache[i].dbc_refcnt == 0)
+                               {
+                                       /* we don't want to use an open cache with different
+                                        * permissions (esp. if we need write but the open
+                                        * cache is read-only).  So close this one if
+                                        * possible, and re-open below.
+                                        *
+                                        * FIXME:  what about the case where the refcount
+                                        * is > 0?  right now, we're using it anyway and
+                                        * just praying.  Can there be more than one open
+                                        * cache to the same db?
+                                        *
+                                        * Also, it's really only necessary to compare the
+                                        * read-only flag, instead of all of the flags,
+                                        * but for now I'm checking all of them.
+                                        */
+                                       lru = i;
+                                       empty = MAXDBCACHE;
+                                       break;
                                }
+                               li->li_dbcache[i].dbc_refcnt++;
+#ifdef NEW_LOGGING
+                               LDAP_LOG( CACHE, DETAIL1, 
+                                       "ldbm_cache_open: cache %d\n", i, 0, 0 );
+#else
+                               Debug( LDAP_DEBUG_TRACE,
+                                   "<= ldbm_cache_open (cache %d)\n", i, 0, 0 );
+#endif
+
+                               ldap_pvt_thread_mutex_unlock( &li->li_dbcache_mutex );
+                               return( &li->li_dbcache[i] );
+                       }
+
+                       /* keep track of lru db */
+                       if (( li->li_dbcache[i].dbc_refcnt == 0 ) &&
+                             (( oldtime == 1 ) ||
+                             ( li->li_dbcache[i].dbc_lastref < oldtime )) )
+                       {
+                               lru = i;
+                               oldtime = li->li_dbcache[i].dbc_lastref;
                        }
-                       i = lru;
                }
-               ldbm_close( li->li_dbcache[i].dbc_db );
-               free( li->li_dbcache[i].dbc_name );
-               li->li_dbcache[i].dbc_name = NULL;
-       }
 
-       if ( (li->li_dbcache[i].dbc_db = ldbm_open( buf, flags, li->li_mode,
-           li->li_dbcachesize )) == NULL ) {
+               i = empty;
+               if ( i == MAXDBCACHE ) {
+                       /* no empty slots, not already open - close lru and use that slot */
+                       if ( li->li_dbcache[lru].dbc_refcnt == 0 ) {
+                               i = lru;
+                               ldbm_close( li->li_dbcache[i].dbc_db );
+                               free( li->li_dbcache[i].dbc_name );
+                               li->li_dbcache[i].dbc_name = NULL;
+                       } else {
+#ifdef NEW_LOGGING
+                               LDAP_LOG( CACHE, INFO,
+                                       "ldbm_cache_open: no unused db to close - waiting\n", 
+                                       0, 0, 0 );
+#else
+                               Debug( LDAP_DEBUG_ANY,
+                                   "ldbm_cache_open no unused db to close - waiting\n",
+                                   0, 0, 0 );
+#endif
+
+                               ldap_pvt_thread_cond_wait( &li->li_dbcache_cv,
+                                           &li->li_dbcache_mutex );
+                               /* after waiting for a free slot, go back to square
+                                * one: look for an open cache for this db, or an
+                                * empty slot, or an unref'ed cache, or wait again.
+                                */
+                       }
+               }
+       } while (i == MAXDBCACHE);
+
+       if ( (li->li_dbcache[i].dbc_db = ldbm_open( li->li_dbenv, buf, flags, li->li_mode,
+           li->li_dbcachesize )) == NULL )
+       {
+               int err = errno;
+#ifdef NEW_LOGGING
+               LDAP_LOG( CACHE, ERR, 
+                       "ldbm_cache_open: \"%s\" failed, errono=%d, reason=%s\n",
+                       buf, err, err > -1 && err < sys_nerr ? sys_errlist[err] :
+                       "unknown" );
+#else
                Debug( LDAP_DEBUG_TRACE,
-                   "<= ldbm_cache_open NULL \"%s\" errno %d reason \"%s\")\n",
-                   buf, errno, errno > -1 && errno < sys_nerr ?
-                   sys_errlist[errno] : "unknown" );
-               pthread_mutex_unlock( &li->li_dbcache_mutex );
+                   "<= ldbm_cache_open NULL \"%s\" errno=%d reason=\"%s\")\n",
+                   buf, err, err > -1 && err < sys_nerr ?
+                   sys_errlist[err] : "unknown" );
+#endif
+
+               ldap_pvt_thread_mutex_unlock( &li->li_dbcache_mutex );
                return( NULL );
        }
        li->li_dbcache[i].dbc_name = ch_strdup( buf );
        li->li_dbcache[i].dbc_refcnt = 1;
-       li->li_dbcache[i].dbc_lastref = curtime;
+       li->li_dbcache[i].dbc_lastref = slap_get_time();
+       li->li_dbcache[i].dbc_flags = flags;
+       li->li_dbcache[i].dbc_dirty = 0;
+#ifdef HAVE_ST_BLKSIZE
        if ( stat( buf, &st ) == 0 ) {
                li->li_dbcache[i].dbc_blksize = st.st_blksize;
-       } else {
+       } else
+#endif
+       {
                li->li_dbcache[i].dbc_blksize = DEFAULT_BLOCKSIZE;
        }
        li->li_dbcache[i].dbc_maxids = (li->li_dbcache[i].dbc_blksize /
-           sizeof(ID)) - 2;
-       li->li_dbcache[i].dbc_maxindirect = (SLAPD_LDBM_MIN_MAXIDS /
-           li->li_dbcache[i].dbc_maxids) + 1;
-
+           sizeof(ID)) - ID_BLOCK_IDS_OFFSET;
+       li->li_dbcache[i].dbc_maxindirect = ( SLAPD_LDBM_MIN_MAXIDS /
+           li->li_dbcache[i].dbc_maxids ) + 1;
+
+       assert( li->li_dbcache[i].dbc_maxindirect < 256 );
+
+#ifdef NEW_LOGGING
+       LDAP_LOG( CACHE, ARGS, 
+                  "ldbm_cache_open: blksize:%ld  maxids:%d  maxindirect:%d\n",
+                  li->li_dbcache[i].dbc_blksize, li->li_dbcache[i].dbc_maxids,
+                  li->li_dbcache[i].dbc_maxindirect );
+#else
        Debug( LDAP_DEBUG_ARGS,
            "ldbm_cache_open (blksize %ld) (maxids %d) (maxindirect %d)\n",
            li->li_dbcache[i].dbc_blksize, li->li_dbcache[i].dbc_maxids,
            li->li_dbcache[i].dbc_maxindirect );
+#endif
+
+#ifdef NEW_LOGGING
+       LDAP_LOG( CACHE, DETAIL1, "<= ldbm_cache_open: (opened %d)\n", i, 0, 0 );
+#else
        Debug( LDAP_DEBUG_TRACE, "<= ldbm_cache_open (opened %d)\n", i, 0, 0 );
-       pthread_mutex_unlock( &li->li_dbcache_mutex );
+#endif
+
+       ldap_pvt_thread_mutex_init( &li->li_dbcache[i].dbc_write_mutex );
+
+       ldap_pvt_thread_mutex_unlock( &li->li_dbcache_mutex );
        return( &li->li_dbcache[i] );
 }
 
 void
-ldbm_cache_close( Backend *be, struct dbcache *db )
+ldbm_cache_close( Backend *be, DBCache *db )
 {
        struct ldbminfo *li = (struct ldbminfo *) be->be_private;
 
-       pthread_mutex_lock( &li->li_dbcache_mutex );
-       if ( --db->dbc_refcnt == 0 ) {
-               pthread_cond_signal( &li->li_dbcache_cv );
+       if( li->li_dbwritesync && db->dbc_dirty ) {
+               ldbm_sync( db->dbc_db );
+               db->dbc_dirty = 0;
+       }
+
+       ldap_pvt_thread_mutex_lock( &li->li_dbcache_mutex );
+       if ( --db->dbc_refcnt <= 0 ) {
+               db->dbc_refcnt = 0;
+               ldap_pvt_thread_cond_signal( &li->li_dbcache_cv );
        }
-       pthread_mutex_unlock( &li->li_dbcache_mutex );
+       ldap_pvt_thread_mutex_unlock( &li->li_dbcache_mutex );
 }
 
 void
-ldbm_cache_really_close( Backend *be, struct dbcache *db )
+ldbm_cache_really_close( Backend *be, DBCache *db )
 {
        struct ldbminfo *li = (struct ldbminfo *) be->be_private;
 
-       pthread_mutex_lock( &li->li_dbcache_mutex );
-       if ( --db->dbc_refcnt == 0 ) {
-               pthread_cond_signal( &li->li_dbcache_cv );
+       ldap_pvt_thread_mutex_lock( &li->li_dbcache_mutex );
+       if ( --db->dbc_refcnt <= 0 ) {
+               db->dbc_refcnt = 0;
+               ldap_pvt_thread_cond_signal( &li->li_dbcache_cv );
                ldbm_close( db->dbc_db );
                free( db->dbc_name );
                db->dbc_name = NULL;
+               ldap_pvt_thread_mutex_destroy( &db->dbc_write_mutex );
        }
-       pthread_mutex_unlock( &li->li_dbcache_mutex );
+       ldap_pvt_thread_mutex_unlock( &li->li_dbcache_mutex );
 }
 
 void
@@ -155,54 +264,90 @@ ldbm_cache_flush_all( Backend *be )
        struct ldbminfo *li = (struct ldbminfo *) be->be_private;
        int             i;
 
-       pthread_mutex_lock( &li->li_dbcache_mutex );
+       ldap_pvt_thread_mutex_lock( &li->li_dbcache_mutex );
        for ( i = 0; i < MAXDBCACHE; i++ ) {
                if ( li->li_dbcache[i].dbc_name != NULL ) {
+#ifdef NEW_LOGGING
+                       LDAP_LOG( CACHE, DETAIL1, 
+                                  "ldbm_cache_flush_all: flushing db (%s)\n",
+                                  li->li_dbcache[i].dbc_name, 0, 0 );
+#else
                        Debug( LDAP_DEBUG_TRACE, "ldbm flushing db (%s)\n",
                            li->li_dbcache[i].dbc_name, 0, 0 );
-                       pthread_mutex_lock( &li->li_dbcache[i].dbc_mutex );
+#endif
+
                        ldbm_sync( li->li_dbcache[i].dbc_db );
-                       pthread_mutex_unlock( &li->li_dbcache[i].dbc_mutex );
+                       li->li_dbcache[i].dbc_dirty = 0;
+                       if ( li->li_dbcache[i].dbc_refcnt != 0 ) {
+#ifdef NEW_LOGGING
+                               LDAP_LOG( CACHE, INFO, 
+                                       "ldbm_cache_flush_all: couldn't close db (%s), refcnt=%d\n",
+                                       li->li_dbcache[i].dbc_name, li->li_dbcache[i].dbc_refcnt,0);
+#else
+                               Debug( LDAP_DEBUG_TRACE,
+                                      "refcnt = %d, couldn't close db (%s)\n",
+                                      li->li_dbcache[i].dbc_refcnt,
+                                      li->li_dbcache[i].dbc_name, 0 );
+#endif
+
+                       } else {
+#ifdef NEW_LOGGING
+                               LDAP_LOG( CACHE, DETAIL1, 
+                                          "ldbm_cache_flush_all: ldbm closing db (%s)\n",
+                                          li->li_dbcache[i].dbc_name, 0, 0 );
+#else
+                               Debug( LDAP_DEBUG_TRACE,
+                                      "ldbm closing db (%s)\n",
+                                      li->li_dbcache[i].dbc_name, 0, 0 );
+#endif
+
+                               ldap_pvt_thread_cond_signal( &li->li_dbcache_cv );
+                               ldbm_close( li->li_dbcache[i].dbc_db );
+                               free( li->li_dbcache[i].dbc_name );
+                               li->li_dbcache[i].dbc_name = NULL;
+                       }
                }
        }
-       pthread_mutex_unlock( &li->li_dbcache_mutex );
+       ldap_pvt_thread_mutex_unlock( &li->li_dbcache_mutex );
 }
 
-Datum
-ldbm_cache_fetch(
-    struct dbcache     *db,
-    Datum              key
-)
+void
+ldbm_cache_sync( Backend *be )
 {
-       Datum   data;
-#ifdef HAVE_BERKELEY_DB2
-       memset( &data, 0, sizeof( data ) );
-#endif
+       struct ldbminfo *li = (struct ldbminfo *) be->be_private;
+       int             i;
 
-       pthread_mutex_lock( &db->dbc_mutex );
-#ifdef reentrant_database
-       /* increment reader count */
-       db->dbc_readers++
-       pthread_mutex_unlock( &db->dbc_mutex );
+       ldap_pvt_thread_mutex_lock( &li->li_dbcache_mutex );
+       for ( i = 0; i < MAXDBCACHE; i++ ) {
+               if ( li->li_dbcache[i].dbc_name != NULL && li->li_dbcache[i].dbc_dirty ) {
+#ifdef NEW_LOGGING
+                       LDAP_LOG ( CACHE, DETAIL1, "ldbm_cache_sync: "
+                               "ldbm syncing db (%s)\n", li->li_dbcache[i].dbc_name, 0, 0 );
+#else
+                       Debug(  LDAP_DEBUG_TRACE, "ldbm syncing db (%s)\n",
+                               li->li_dbcache[i].dbc_name, 0, 0 );
 #endif
-
-       data = ldbm_fetch( db->dbc_db, key );
-
-#ifdef reentrant_database
-       pthread_mutex_lock( &db->dbc_mutex );
-       /* decrement reader count & signal any waiting writers */
-       if ( --db->dbc_readers == 0 ) {
-               pthread_cond_signal( &db->dbc_cv );
+                       ldbm_sync( li->li_dbcache[i].dbc_db );
+                       li->li_dbcache[i].dbc_dirty = 0;
+               }
        }
-#endif
-       pthread_mutex_unlock( &db->dbc_mutex );
+       ldap_pvt_thread_mutex_unlock( &li->li_dbcache_mutex );
+}
 
-       return( data );
+#if 0 /* macro in proto-back-ldbm.h */
+Datum
+ldbm_cache_fetch(
+    DBCache    *db,
+    Datum              key
+)
+{
+       return ldbm_fetch( db->dbc_db, key );
 }
+#endif /* 0 */
 
 int
 ldbm_cache_store(
-    struct dbcache     *db,
+    DBCache    *db,
     Datum              key,
     Datum              data,
     int                        flags
@@ -210,58 +355,74 @@ ldbm_cache_store(
 {
        int     rc;
 
-       pthread_mutex_lock( &db->dbc_mutex );
-#ifdef reentrant_database
-       /* wait for reader count to drop to zero */
-       while ( db->dbc_readers > 0 ) {
-               pthread_cond_wait( &db->dbc_cv, &db->dbc_mutex );
-       }
-#endif
-
-#ifdef LDBM_DEBUG
-       Statslog( LDAP_DEBUG_STATS,
-               "=> ldbm_cache_store(): key.dptr=%s, key.dsize=%d\n",
-               key.dptr, key.dsize, 0, 0, 0 );
-
-       Statslog( LDAP_DEBUG_STATS,
-               "=> ldbm_cache_store(): key.dptr=0x%08x, data.dptr=0x%0 8x\n",
-               key.dptr, data.dptr, 0, 0, 0 );
-
-       Statslog( LDAP_DEBUG_STATS,
-               "=> ldbm_cache_store(): data.dptr=%s, data.dsize=%d\n",
-               data.dptr, data.dsize, 0, 0, 0 );
-
-       Statslog( LDAP_DEBUG_STATS,
-               "=> ldbm_cache_store(): flags=0x%08x\n",
-               flags, 0, 0, 0, 0 );
-#endif /* LDBM_DEBUG */
-
+       db->dbc_dirty = 1;
        rc = ldbm_store( db->dbc_db, key, data, flags );
 
-       pthread_mutex_unlock( &db->dbc_mutex );
-
        return( rc );
 }
 
 int
 ldbm_cache_delete(
-    struct dbcache     *db,
+    DBCache    *db,
     Datum              key
 )
 {
        int     rc;
 
-       pthread_mutex_lock( &db->dbc_mutex );
-#ifdef reentrant_database
-       /* wait for reader count to drop to zero - then write */
-       while ( db->dbc_readers > 0 ) {
-               pthread_cond_wait( &db->dbc_cv, &db->dbc_mutex );
-       }
-#endif
-
+       db->dbc_dirty = 1;
        rc = ldbm_delete( db->dbc_db, key );
 
-       pthread_mutex_unlock( &db->dbc_mutex );
-
        return( rc );
 }
+
+void *
+ldbm_cache_sync_daemon(
+       void *be_ptr
+)
+{
+       Backend *be = (Backend *)be_ptr;
+       struct ldbminfo *li = (struct ldbminfo *) be->be_private;
+
+#ifdef NEW_LOGGING
+       LDAP_LOG ( CACHE, ARGS, "ldbm_cache_sync_daemon:"
+               " synchronizer starting for %s\n", li->li_directory, 0, 0 );
+#else
+       Debug( LDAP_DEBUG_ANY, "synchronizer starting for %s\n", li->li_directory, 0, 0 );
+#endif
+  
+       while (!li->li_dbshutdown) {
+               int i = li->li_dbsyncwaitn;
+
+               sleep( li->li_dbsyncfreq );
+
+               while (i && ldap_pvt_thread_pool_backload(&connection_pool) != 0) {
+#ifdef NEW_LOGGING
+                       LDAP_LOG ( CACHE, DETAIL1, "ldbm_cache_sync_daemon:"
+                               " delay syncing %s\n", li->li_directory, 0, 0 );
+#else
+                       Debug( LDAP_DEBUG_TRACE, "delay syncing %s\n", li->li_directory, 0, 0 );
+#endif
+                       sleep(li->li_dbsyncwaitinterval);
+                       i--;
+               }
+
+               if (!li->li_dbshutdown) {
+#ifdef NEW_LOGGING
+                       LDAP_LOG ( CACHE, DETAIL1, "ldbm_cache_sync_daemon:"
+                               " syncing %s\n", li->li_directory, 0, 0 );
+#else
+                       Debug( LDAP_DEBUG_TRACE, "syncing %s\n", li->li_directory, 0, 0 );
+#endif
+                       ldbm_cache_sync( be );
+               }
+       }
+
+#ifdef NEW_LOGGING
+       LDAP_LOG ( CACHE, DETAIL1, "ldbm_cache_sync_daemon:"
+                               " synchronizer stopping\n", 0, 0, 0);
+#else
+       Debug( LDAP_DEBUG_ANY, "synchronizer stopping\n", 0, 0, 0 );
+#endif
+  
+       return NULL;
+}