From: Pekka Enberg <[email protected]>
As suggested by Eric Dumazet, this patch optimizes kzalloc() calls
that pass a compile-time constant size. Please note that the patch
increases kernel text slightly (~200 bytes for defconfig on x86).
This patch requires the kmem_cache_zalloc() patches I sent earlier.
Signed-off-by: Pekka Enberg <[email protected]>
---
include/linux/slab.h | 30 +++++++++++++++++++++++++++---
mm/util.c | 6 +++---
2 files changed, 30 insertions(+), 6 deletions(-)
diff --git a/include/linux/slab.h b/include/linux/slab.h
index b595c09..db3b302 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -109,7 +109,30 @@ found:
return __kmalloc(size, flags);
}
-extern void *kzalloc(size_t, gfp_t);
+extern void *__kzalloc(size_t, gfp_t);
+
+static inline void *kzalloc(size_t size, gfp_t flags)
+{
+ if (__builtin_constant_p(size)) {
+ int i = 0;
+#define CACHE(x) \
+ if (size <= x) \
+ goto found; \
+ else \
+ i++;
+#include "kmalloc_sizes.h"
+#undef CACHE
+ {
+ extern void __you_cannot_kzalloc_that_much(void);
+ __you_cannot_kzalloc_that_much();
+ }
+found:
+ return kmem_cache_zalloc((flags & GFP_DMA) ?
+ malloc_sizes[i].cs_dmacachep :
+ malloc_sizes[i].cs_cachep, flags);
+ }
+ return __kzalloc(size, flags);
+}
/**
* kcalloc - allocate memory for an array. The memory is set to zero.
@@ -160,14 +183,14 @@ void *kmem_cache_zalloc(struct kmem_cach
void kmem_cache_free(struct kmem_cache *c, void *b);
const char *kmem_cache_name(struct kmem_cache *);
void *kmalloc(size_t size, gfp_t flags);
-void *kzalloc(size_t size, gfp_t flags);
+void *__kzalloc(size_t size, gfp_t flags);
void kfree(const void *m);
unsigned int ksize(const void *m);
unsigned int kmem_cache_size(struct kmem_cache *c);
static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
{
- return kzalloc(n * size, flags);
+ return __kzalloc(n * size, flags);
}
#define kmem_cache_shrink(d) (0)
@@ -175,6 +198,7 @@ static inline void *kcalloc(size_t n, si
#define kmem_ptr_validate(a, b) (0)
#define kmem_cache_alloc_node(c, f, n) kmem_cache_alloc(c, f)
#define kmalloc_node(s, f, n) kmalloc(s, f)
+#define kzalloc(s, f) __kzalloc(s, f)
#endif /* CONFIG_SLOB */
diff --git a/mm/util.c b/mm/util.c
index 5f4bb59..fd78ee4 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -3,18 +3,18 @@
#include <linux/module.h>
/**
- * kzalloc - allocate memory. The memory is set to zero.
+ * __kzalloc - allocate memory. The memory is set to zero.
* @size: how many bytes of memory are required.
* @flags: the type of memory to allocate.
*/
-void *kzalloc(size_t size, gfp_t flags)
+void *__kzalloc(size_t size, gfp_t flags)
{
void *ret = kmalloc(size, flags);
if (ret)
memset(ret, 0, size);
return ret;
}
-EXPORT_SYMBOL(kzalloc);
+EXPORT_SYMBOL(__kzalloc);
/*
* kstrdup - allocate space for and copy an existing string
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
