#include <linux/mutex.h>
#include <linux/fault-inject.h>
#include <linux/rtmutex.h>
+#include <linux/reciprocal_div.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
unsigned int shared;
unsigned int buffer_size;
+ u32 reciprocal_buffer_size;
/* 3) touched by every alloc & free from the backend */
struct kmem_list3 *nodelists[MAX_NUMNODES];
return slab->s_mem + cache->buffer_size * idx;
}
-static inline unsigned int obj_to_index(struct kmem_cache *cache,
- struct slab *slab, void *obj)
+/*
+ * We want to avoid an expensive divide : (offset / cache->buffer_size)
+ * Using the fact that buffer_size is a constant for a particular cache,
+ * we can replace (offset / cache->buffer_size) by
+ * reciprocal_divide(offset, cache->reciprocal_buffer_size)
+ */
+static inline unsigned int obj_to_index(const struct kmem_cache *cache,
+ const struct slab *slab, void *obj)
{
- return (unsigned)(obj - slab->s_mem) / cache->buffer_size;
+ u32 offset = (obj - slab->s_mem);
+ return reciprocal_divide(offset, cache->reciprocal_buffer_size);
}
/*
cache_cache.buffer_size = ALIGN(cache_cache.buffer_size,
cache_line_size());
+ cache_cache.reciprocal_buffer_size =
+ reciprocal_value(cache_cache.buffer_size);
for (order = 0; order < MAX_ORDER; order++) {
cache_estimate(order, cache_cache.buffer_size,
if (flags & SLAB_CACHE_DMA)
cachep->gfpflags |= GFP_DMA;
cachep->buffer_size = size;
+ cachep->reciprocal_buffer_size = reciprocal_value(size);
if (flags & CFLGS_OFF_SLAB) {
cachep->slabp_cache = kmem_find_general_cachep(slab_size, 0u);
flags | GFP_THISNODE, nid);
}
- if (!obj) {
+ if (!obj && !(flags & __GFP_NO_GROW)) {
/*
* This allocation will be performed within the constraints
* of the current cpuset / memory policy requirements.
*/
goto retry;
} else {
- kmem_freepages(cache, obj);
+ /* cache_grow already freed obj */
obj = NULL;
}
}
*
* Currently only used for dentry validation.
*/
-int fastcall kmem_ptr_validate(struct kmem_cache *cachep, const void *ptr)
+int kmem_ptr_validate(struct kmem_cache *cachep, const void *ptr)
{
unsigned long addr = (unsigned long)ptr;
unsigned long min_addr = PAGE_OFFSET;
* @cachep: The cache to allocate from.
* @flags: See kmalloc().
* @nodeid: node number of the target node.
+ * @caller: return address of caller, used for debug information
*
* Identical to kmem_cache_alloc but it will allocate memory on the given
* node, which can improve the performance for cpu bound structures.