[PATCH] mm: faster kmalloc_array(), kcalloc()
From: Alexey Dobriyan
Date: Mon Jun 27 2016 - 17:35:05 EST
When both arguments to kmalloc_array() or kcalloc() are known at
compile time then their product is known at compile time
but search for kmalloc cache happens at runtime not at compile time.
Signed-off-by: Alexey Dobriyan <adobriyan@xxxxxxxxx>
---
include/linux/slab.h | 2 ++
1 file changed, 2 insertions(+)
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -565,6 +565,8 @@ static inline void *kmalloc_array(size_t n, size_t size, gfp_t flags)
{
if (size != 0 && n > SIZE_MAX / size)
return NULL;
+ if (__builtin_constant_p(n) && __builtin_constant_p(size))
+ return kmalloc(n * size, flags);
return __kmalloc(n * size, flags);
}