Import ITS#4439 (slapd not responding) fix for BDB/HDB cache from HEAD

diff --git a/CHANGES b/CHANGES
index d88e359830286c5b390092cace6c93140f6fe077..7ba1f45c072a7aa0e20945e74a0788d3ca8ea8fa 100644 (file)
--- a/CHANGES
+++ b/CHANGES
@@ -12,6 +12,7 @@ OpenLDAP 2.3.21 Release
        Fixed slapd connection index bound check (ITS#4449)
        Fixed slapd connection cleanup (ITS#4465)
        Fixed slapd slap_realloc misuse (ITS#4477)
+       Fixed slapd-bdb/hdb cache issue (ITS#4439)
        Fixed slapd-ldbm crash on modify bug (ITS#4464)
        Fixed slapd-ldap potential bind deadlock (ITS#4409)
        Fixed slapd-ldap/meta conn expiration concurrency (ITS#4429)

diff --git a/servers/slapd/back-bdb/back-bdb.h b/servers/slapd/back-bdb/back-bdb.h
index 4405d82f50e2a796eb33a100260c300238848235..c6788417e9a3a1a34b76d083fabd12eb6d662244 100644 (file)
--- a/servers/slapd/back-bdb/back-bdb.h
+++ b/servers/slapd/back-bdb/back-bdb.h
@@ -180,7 +180,6 @@ struct bdb_info {
        u_int32_t       bi_txn_cp_kbyte;
        struct re_s             *bi_txn_cp_task;
        struct re_s             *bi_index_task;
-       struct re_s             *bi_cache_task;
 
        int                     bi_lock_detect;
        long            bi_shm_key;

diff --git a/servers/slapd/back-bdb/cache.c b/servers/slapd/back-bdb/cache.c
index 1fdeafda92f90742a0e33f381d1569d477341ca2..4bff759a9e14febe0c78280a9b83661b7343feb9 100644 (file)
--- a/servers/slapd/back-bdb/cache.c
+++ b/servers/slapd/back-bdb/cache.c
@@ -186,8 +186,10 @@ bdb_cache_entryinfo_destroy( EntryInfo *e )
        } \
        (cache)->c_lruhead = (ei); \
        (ei)->bei_lruprev = NULL; \
-       if ( (cache)->c_lrutail == NULL ) { \
-               (cache)->c_lrutail = (ei); \
+       if ( !ldap_pvt_thread_mutex_trylock( &(cache)->lru_tail_mutex )) { \
+               if ( (cache)->c_lrutail == NULL ) \
+                       (cache)->c_lrutail = (ei); \
+               ldap_pvt_thread_mutex_unlock( &(cache)->lru_tail_mutex ); \
        } \
 } while(0)
 
@@ -529,15 +531,25 @@ int hdb_cache_load(
 }
 #endif
 
-static void *
-bdb_cache_lru_purge(void *ctx, void *arg)
+/* caller must have lru_head_mutex locked. mutex
+ * will be unlocked on return.
+ */
+static void
+bdb_cache_lru_add(
+       struct bdb_info *bdb,
+       EntryInfo *ei )
 {
-       struct re_s *rtask = arg;
-       struct bdb_info *bdb = rtask->arg;
        DB_LOCK         lock, *lockp;
        EntryInfo *elru, *elprev;
        int count = 0;
 
+       LRU_ADD( &bdb->bi_cache, ei );
+       ldap_pvt_thread_mutex_unlock( &bdb->bi_cache.lru_head_mutex );
+
+       /* See if we're above the cache size limit */
+       if ( bdb->bi_cache.c_cursize <= bdb->bi_cache.c_maxsize )
+               return;
+
        if ( bdb->bi_cache.c_locker ) {
                lockp = &lock;
        } else {
@@ -610,63 +622,6 @@ bdb_cache_lru_purge(void *ctx, void *arg)
        }
 
        ldap_pvt_thread_mutex_unlock( &bdb->bi_cache.lru_tail_mutex );
-
-       /* If we're running as a task, drop the task */
-       if ( ctx ) {
-               ldap_pvt_thread_mutex_lock( &slapd_rq.rq_mutex );
-               ldap_pvt_runqueue_stoptask( &slapd_rq, rtask );
-               /* Defer processing till we're needed again */
-               ldap_pvt_runqueue_resched( &slapd_rq, rtask, 1 );
-               ldap_pvt_thread_mutex_unlock( &slapd_rq.rq_mutex );
-       }
-
-       return NULL;
-}
-
-/* caller must have lru_head_mutex locked. mutex
- * will be unlocked on return.
- */
-static void
-bdb_cache_lru_add(
-       struct bdb_info *bdb,
-       EntryInfo *ei )
-{
-       LRU_ADD( &bdb->bi_cache, ei );
-       ldap_pvt_thread_mutex_unlock( &bdb->bi_cache.lru_head_mutex );
-
-       /* See if we're above the cache size limit */
-       if ( bdb->bi_cache.c_cursize > bdb->bi_cache.c_maxsize ) {
-               if ( slapMode & SLAP_TOOL_MODE ) {
-                       struct re_s rtask;
-
-                       rtask.arg = bdb;
-                       bdb_cache_lru_purge( NULL, &rtask );
-               } else {
-                       int wake = 0;
-                       ldap_pvt_thread_mutex_lock( &slapd_rq.rq_mutex );
-                       if ( bdb->bi_cache_task ) {
-                               if ( !ldap_pvt_runqueue_isrunning( &slapd_rq,
-                                       bdb->bi_cache_task )) {
-                                       /* We want it to start right now */
-                                       bdb->bi_cache_task->interval.tv_sec = 0;
-                                       ldap_pvt_runqueue_resched( &slapd_rq, bdb->bi_cache_task,
-                                               0 );
-                                       /* But don't try to reschedule it while it's running */
-                                       bdb->bi_cache_task->interval.tv_sec = 3600;
-                                       wake = 1;
-                               }
-                       } else {
-                               bdb->bi_cache_task = ldap_pvt_runqueue_insert( &slapd_rq, 3600,
-                                       bdb_cache_lru_purge, bdb, "bdb_cache_lru_purge",
-                                       bdb->bi_dbenv_home );
-                               wake = 1;
-                       }
-                       ldap_pvt_thread_mutex_unlock( &slapd_rq.rq_mutex );
-                       /* Don't bother waking if the purge task is already running */
-                       if ( wake )
-                               slap_wake_listener();
-               }
-       }
 }
 
 EntryInfo *
@@ -765,12 +720,12 @@ 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 && *eip ) islocked = 1;
+               if ( rc == 0 ) islocked = 1;
 #endif
        }
 
        /* Ok, we found the info, do we have the entry? */
-       if ( *eip && rc == 0 ) {
+       if ( rc == 0 ) {
                if ( (*eip)->bei_state & CACHE_ENTRY_DELETED ) {
                        rc = DB_NOTFOUND;
                } else {

diff --git a/servers/slapd/back-bdb/id2entry.c b/servers/slapd/back-bdb/id2entry.c
index f362739185eac099f3f190bc56105f847879357f..869c217aad1899c20290640f3c02a15d792a7bf2 100644 (file)
--- a/servers/slapd/back-bdb/id2entry.c
+++ b/servers/slapd/back-bdb/id2entry.c
@@ -258,9 +258,8 @@ int bdb_entry_release(
 #endif
                }
                /* free entry and reader or writer lock */
-               if ( op ) {
-                       boi = (struct bdb_op_info *)op->o_private;
-               }
+               boi = (struct bdb_op_info *)op->o_private;
+
                /* lock is freed with txn */
                if ( !boi || boi->boi_txn ) {
                        bdb_unlocked_cache_return_entry_rw( &bdb->bi_cache, e, rw );

diff --git a/servers/slapd/back-bdb/idl.c b/servers/slapd/back-bdb/idl.c
index 84629c10cf6e777a09059c966b5b96f990b1ecab..97cf1bd8e2c30d8a7b64aef2008137c22e41a653 100644 (file)
--- a/servers/slapd/back-bdb/idl.c
+++ b/servers/slapd/back-bdb/idl.c
@@ -473,8 +473,7 @@ bdb_idl_cache_del_id(
                        IDL_LRU_DELETE( bdb, cache_entry );
                        ldap_pvt_thread_mutex_unlock( &bdb->bi_idl_tree_lrulock );
                        free( cache_entry->kstr.bv_val );
-                       if ( cache_entry->idl )
-                               free( cache_entry->idl );
+                       free( cache_entry->idl );
                        free( cache_entry );
                }
        }