void
object_depot_destroy(object_depot* depot, uint32 flags)
{
object_depot_make_empty(depot, flags);
slab_internal_free(depot->stores, flags);
rw_lock_destroy(&depot->outer_lock);
}
static void
object_cache_low_memory(void* dummy, uint32 resources, int32 level)
{
if (level == B_NO_LOW_RESOURCE)
return;
MutexLocker cacheListLocker(sObjectCacheListLock);
// Append the first cache to the end of the queue. We assume that it is
// one of the caches that will never be deleted and thus we use it as a
// marker.
ObjectCache* firstCache = sObjectCaches.RemoveHead();
sObjectCaches.Add(firstCache);
cacheListLocker.Unlock();
ObjectCache* cache;
do {
cacheListLocker.Lock();
cache = sObjectCaches.RemoveHead();
sObjectCaches.Add(cache);
MutexLocker maintenanceLocker(sMaintenanceLock);
if (cache->maintenance_pending || cache->maintenance_in_progress) {
// We don't want to mess with caches in maintenance.
continue;
}
cache->maintenance_pending = true;
cache->maintenance_in_progress = true;
maintenanceLocker.Unlock();
cacheListLocker.Unlock();
// We are calling the reclaimer without the object cache lock
// to give the owner a chance to return objects to the slabs.
if (cache->reclaimer)
cache->reclaimer(cache->cookie, level);
if ((cache->flags & CACHE_NO_DEPOT) == 0)
object_depot_make_empty(&cache->depot, 0);
MutexLocker cacheLocker(cache->lock);
size_t minimumAllowed;
switch (level) {
case B_LOW_RESOURCE_NOTE:
minimumAllowed = cache->pressure / 2 + 1;
cache->pressure -= cache->pressure / 8;
break;
case B_LOW_RESOURCE_WARNING:
cache->pressure /= 2;
minimumAllowed = 0;
break;
default:
cache->pressure = 0;
minimumAllowed = 0;
break;
}
while (cache->empty_count > minimumAllowed) {
// make sure we respect the cache's minimum object reserve
size_t objectsPerSlab = cache->empty.Head()->size;
size_t freeObjects = cache->total_objects - cache->used_count;
if (freeObjects < cache->min_object_reserve + objectsPerSlab)
break;
cache->ReturnSlab(cache->empty.RemoveHead(), 0);
cache->empty_count--;
}
cacheLocker.Unlock();
// Check whether in the meantime someone has really requested
// maintenance for the cache.
maintenanceLocker.Lock();
if (cache->maintenance_delete) {
delete_object_cache_internal(cache);
continue;
}
cache->maintenance_in_progress = false;
if (cache->maintenance_resize)
sMaintenanceQueue.Add(cache);
else
cache->maintenance_pending = false;
} while (cache != firstCache);
}
