X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=mm%2Fslab.c;h=a9ff4f7f9860b2f1f37891fe4fe8c50a5caa637d;hb=e752dd6cc66a3e6a11396928998baf390cc00420;hp=59d382fbca1ccf74faafe538b600d92e4ea01dd0;hpb=fa5b08d5f818063d18433194f20359ef2ae50254;p=linux-2.6

diff --git a/mm/slab.c b/mm/slab.c
index 59d382fbca..a9ff4f7f98 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -2166,7 +2166,9 @@ static inline void *__cache_alloc(kmem_cache_t *cachep, unsigned int __nocast fl
 		objp = cache_alloc_refill(cachep, flags);
 	}
 	local_irq_restore(save_flags);
-	objp = cache_alloc_debugcheck_after(cachep, flags, objp, __builtin_return_address(0));
+	objp = cache_alloc_debugcheck_after(cachep, flags, objp,
+					__builtin_return_address(0));
+	prefetchw(objp);
 	return objp;
 }
 
@@ -3074,20 +3076,24 @@ ssize_t slabinfo_write(struct file *file, const char __user *buffer,
 }
 #endif
 
+/**
+ * ksize - get the actual amount of memory allocated for a given object
+ * @objp: Pointer to the object
+ *
+ * kmalloc may internally round up allocations and return more memory
+ * than requested. ksize() can be used to determine the actual amount of
+ * memory allocated. The caller may use this additional memory, even though
+ * a smaller amount of memory was initially specified with the kmalloc call.
+ * The caller must guarantee that objp points to a valid object previously
+ * allocated with either kmalloc() or kmem_cache_alloc(). The object
+ * must not be freed during the duration of the call.
+ */
 unsigned int ksize(const void *objp)
 {
-	kmem_cache_t *c;
-	unsigned long flags;
-	unsigned int size = 0;
-
-	if (likely(objp != NULL)) {
-		local_irq_save(flags);
-		c = GET_PAGE_CACHE(virt_to_page(objp));
-		size = kmem_cache_size(c);
-		local_irq_restore(flags);
-	}
+	if (unlikely(objp == NULL))
+		return 0;
 
-	return size;
+	return obj_reallen(GET_PAGE_CACHE(virt_to_page(objp)));
 }