diff options
Diffstat (limited to 'nscd/cache.c')
-rw-r--r-- | nscd/cache.c | 60 |
1 files changed, 42 insertions, 18 deletions
diff --git a/nscd/cache.c b/nscd/cache.c index 6492092..10b04c3c 100644 --- a/nscd/cache.c +++ b/nscd/cache.c @@ -44,11 +44,14 @@ cache_search (request_type type, void *key, size_t len, struct database *table, { unsigned long int hash = __nis_hash (key, len) % table->module; struct hashentry *work; + unsigned long int nsearched = 0; work = table->array[hash]; while (work != NULL) { + ++nsearched; + if (type == work->type && len == work->len && memcmp (key, work->key, len) == 0 && work->owner == owner) { @@ -58,13 +61,16 @@ cache_search (request_type type, void *key, size_t len, struct database *table, else ++table->poshit; - return work; + break; } work = work->next; } - return NULL; + if (nsearched > table->maxnsearched) + table->maxnsearched = nsearched; + + return work; } /* Add a new entry to the cache. The return value is zero if the function @@ -109,6 +115,12 @@ cache_add (int type, void *key, size_t len, const void *packet, size_t total, ++table->negmiss; else if (last) ++table->posmiss; + + /* Instead of slowing down the normal process for statistics + collection we accept living with some incorrect data. */ + unsigned long int nentries = ++table->nentries; + if (nentries > table->maxnentries) + table->maxnentries = nentries; } /* Walk through the table and remove all entries which lifetime ended. @@ -165,10 +177,10 @@ prune_cache (struct database *table, time_t now) /* We run through the table and find values which are not valid anymore. - Note that for the initial step, finding the entries to be removed, - we don't need to get any lock. It is at all timed assured that the - linked lists are set up correctly and that no second thread prunes - the cache. */ + Note that for the initial step, finding the entries to be removed, + we don't need to get any lock. It is at all timed assured that the + linked lists are set up correctly and that no second thread prunes + the cache. */ do { struct hashentry *runp = table->array[--cnt]; @@ -195,7 +207,11 @@ prune_cache (struct database *table, time_t now) /* Now we have to get the write lock since we are about to modify the table. */ - pthread_rwlock_wrlock (&table->lock); + if (__builtin_expect (pthread_rwlock_trywrlock (&table->lock) != 0, 0)) + { + ++table->wrlockdelayed; + pthread_rwlock_wrlock (&table->lock); + } while (first <= last) { @@ -208,6 +224,7 @@ prune_cache (struct database *table, time_t now) table->array[first]->dellist = head; head = table->array[first]; table->array[first] = head->next; + --table->nentries; if (--mark[first] == 0) break; } @@ -221,6 +238,7 @@ prune_cache (struct database *table, time_t now) head = runp->next; runp->next = head->next; --mark[first]; + --table->nentries; } else runp = runp->next; @@ -232,29 +250,35 @@ prune_cache (struct database *table, time_t now) /* It's all done. */ pthread_rwlock_unlock (&table->lock); - /* And another run to free the data. */ - do + /* One extra pass if we do debugging. */ + if (__builtin_expect (debug_level > 0, 0)) { - struct hashentry *old = head; + struct hashentry *runp = head; - if (debug_level > 0) + while (runp != NULL) { char buf[INET6_ADDRSTRLEN]; const char *str; - if ((old->type == GETHOSTBYADDR || old->type == GETHOSTBYADDRv6) - && (old->last || old->data == (void *) -1)) + if (runp->type == GETHOSTBYADDR || runp->type == GETHOSTBYADDRv6) { - inet_ntop (old->type == GETHOSTBYADDR ? AF_INET : AF_INET6, - old->key, buf, sizeof (buf)); + inet_ntop (runp->type == GETHOSTBYADDR ? AF_INET : AF_INET6, + runp->key, buf, sizeof (buf)); str = buf; } else - str = old->last ? old->key : (old->data == (void *) -1 - ? old->key : "???"); + str = runp->key; - dbg_log ("remove %s entry \"%s\"", serv2str[old->type], str); + dbg_log ("remove %s entry \"%s\"", serv2str[runp->type], str); + + runp = runp->next; } + } + + /* And another run to free the data. */ + do + { + struct hashentry *old = head; /* Free the data structures. */ if (old->data == (void *) -1) |