* Reverted r35203, i.e. ObjectCache::object_per_slab is gone again.

* Changed the semantics of object_cache_reserve_internal(). Now it makes sure
  the given number of objects are free. As a side effect this also changes
  the semantics of object_cache_reserve() similarly, though I have trouble
  seeing the purpose of the function in the first place.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@35204 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/system/kernel/slab/HashedObjectCache.cpp

@@ -72,8 +72,6 @@ HashedObjectCache::Create(const char* name, size_t object_size,
 		cache->slab_size = max_c(16 * B_PAGE_SIZE, 8 * object_size);
 	cache->lower_boundary = __fls0(cache->object_size);
 
-	cache->objects_per_slab = cache->slab_size / cache->object_size;
-
 	return cache;
 }
 

src/system/kernel/slab/ObjectCache.h

@@ -47,7 +47,6 @@ struct ObjectCache : DoublyLinkedListLinkImpl<ObjectCache> {
 									// minimum number of free objects
 
 			size_t				slab_size;
-			size_t				objects_per_slab;
 			size_t				usage;
 			size_t				maximum;
 			uint32				flags;

src/system/kernel/slab/Slab.cpp

@@ -312,20 +312,19 @@ increase_object_reserve(ObjectCache* cache)
 }
 
 
+/*!	Makes sure that \a objectCount objects can be allocated.
+*/
 static status_t
 object_cache_reserve_internal(ObjectCache* cache, size_t objectCount,
 	uint32 flags, bool unlockWhileAllocating)
 {
-	size_t slabCount = (objectCount - 1) / cache->objects_per_slab + 1;
+	while (objectCount > cache->total_objects - cache->used_count) {
-
-	while (slabCount > 0) {
 		slab* newSlab = cache->CreateSlab(flags, unlockWhileAllocating);
 		if (newSlab == NULL)
 			return B_NO_MEMORY;
 
 		cache->empty.Add(newSlab);
 		cache->empty_count++;
-		slabCount--;
 	}
 
 	return B_OK;
@@ -422,20 +421,14 @@ object_cache_resizer(void*)
 
 		MutexLocker cacheLocker(cache->lock);
 
-		size_t freeObjects = cache->total_objects - cache->used_count;
-
-		while (freeObjects < cache->min_object_reserve) {
 		status_t error = object_cache_reserve_internal(cache,
-				cache->min_object_reserve - freeObjects, 0, true);
+			cache->min_object_reserve, 0, true);
 		if (error != B_OK) {
 			dprintf("object cache resizer: Failed to resize object cache "
 				"%p!\n", cache);
 			break;
 		}
 
-			freeObjects = cache->total_objects - cache->used_count;
-		}
-
 		request->pending = false;
 
 		if (request->delete_when_done)

src/system/kernel/slab/SmallObjectCache.cpp

@@ -35,9 +35,6 @@ SmallObjectCache::Create(const char* name, size_t object_size,
 	else
 		cache->slab_size = B_PAGE_SIZE;
 
-	cache->objects_per_slab = (cache->slab_size - sizeof(slab))
-		/ cache->object_size;
-
 	return cache;
 }