Re: [RFC PATCH 4/4] kmemtrace: SLOB hooks.

From: Pekka Enberg
Date: Mon Jul 28 2008 - 05:41:50 EST


On Tue, 2008-07-22 at 21:36 +0300, Eduard - Gabriel Munteanu wrote:
> This adds hooks for the SLOB allocator, to allow tracing with kmemtrace.
>

The patch description could be little less terse and maybe explain the
__always_inline changes but:

Reviewed-by: Pekka Enberg <penberg@xxxxxxxxxxxxxx>

> Signed-off-by: Eduard - Gabriel Munteanu <eduard.munteanu@xxxxxxxxxxx>
> ---
> include/linux/slob_def.h | 9 +++++----
> mm/slob.c | 37 +++++++++++++++++++++++++++++++------
> 2 files changed, 36 insertions(+), 10 deletions(-)
>
> diff --git a/include/linux/slob_def.h b/include/linux/slob_def.h
> index 59a3fa4..0ec00b3 100644
> --- a/include/linux/slob_def.h
> +++ b/include/linux/slob_def.h
> @@ -3,14 +3,15 @@
>
> void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
>
> -static inline void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags)
> +static __always_inline void *kmem_cache_alloc(struct kmem_cache *cachep,
> + gfp_t flags)
> {
> return kmem_cache_alloc_node(cachep, flags, -1);
> }
>
> void *__kmalloc_node(size_t size, gfp_t flags, int node);
>
> -static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
> +static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
> {
> return __kmalloc_node(size, flags, node);
> }
> @@ -23,12 +24,12 @@ static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
> * kmalloc is the normal method of allocating memory
> * in the kernel.
> */
> -static inline void *kmalloc(size_t size, gfp_t flags)
> +static __always_inline void *kmalloc(size_t size, gfp_t flags)
> {
> return __kmalloc_node(size, flags, -1);
> }
>
> -static inline void *__kmalloc(size_t size, gfp_t flags)
> +static __always_inline void *__kmalloc(size_t size, gfp_t flags)
> {
> return kmalloc(size, flags);
> }
> diff --git a/mm/slob.c b/mm/slob.c
> index a3ad667..23375ed 100644
> --- a/mm/slob.c
> +++ b/mm/slob.c
> @@ -65,6 +65,7 @@
> #include <linux/module.h>
> #include <linux/rcupdate.h>
> #include <linux/list.h>
> +#include <linux/kmemtrace.h>
> #include <asm/atomic.h>
>
> /*
> @@ -463,27 +464,38 @@ void *__kmalloc_node(size_t size, gfp_t gfp, int node)
> {
> unsigned int *m;
> int align = max(ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
> + void *ret;
>
> if (size < PAGE_SIZE - align) {
> if (!size)
> return ZERO_SIZE_PTR;
>
> m = slob_alloc(size + align, gfp, align, node);
> +
> if (!m)
> return NULL;
> *m = size;
> - return (void *)m + align;
> + ret = (void *)m + align;
> +
> + kmemtrace_mark_alloc_node(KMEMTRACE_TYPE_KMALLOC,
> + _RET_IP_, ret,
> + size, size + align, gfp, node);
> } else {
> - void *ret;
> + unsigned int order = get_order(size);
>
> - ret = slob_new_page(gfp | __GFP_COMP, get_order(size), node);
> + ret = slob_new_page(gfp | __GFP_COMP, order, node);
> if (ret) {
> struct page *page;
> page = virt_to_page(ret);
> page->private = size;
> }
> - return ret;
> +
> + kmemtrace_mark_alloc_node(KMEMTRACE_TYPE_KMALLOC,
> + _RET_IP_, ret,
> + size, PAGE_SIZE << order, gfp, node);
> }
> +
> + return ret;
> }
> EXPORT_SYMBOL(__kmalloc_node);
>
> @@ -501,6 +513,8 @@ void kfree(const void *block)
> slob_free(m, *m + align);
> } else
> put_page(&sp->page);
> +
> + kmemtrace_mark_free(KMEMTRACE_TYPE_KMALLOC, _RET_IP_, block);
> }
> EXPORT_SYMBOL(kfree);
>
> @@ -569,10 +583,19 @@ void *kmem_cache_alloc_node(struct kmem_cache *c, gfp_t flags, int node)
> {
> void *b;
>
> - if (c->size < PAGE_SIZE)
> + if (c->size < PAGE_SIZE) {
> b = slob_alloc(c->size, flags, c->align, node);
> - else
> + kmemtrace_mark_alloc_node(KMEMTRACE_TYPE_CACHE,
> + _RET_IP_, b, c->size,
> + SLOB_UNITS(c->size) * SLOB_UNIT,
> + flags, node);
> + } else {
> b = slob_new_page(flags, get_order(c->size), node);
> + kmemtrace_mark_alloc_node(KMEMTRACE_TYPE_CACHE,
> + _RET_IP_, b, c->size,
> + PAGE_SIZE << get_order(c->size),
> + flags, node);
> + }
>
> if (c->ctor)
> c->ctor(c, b);
> @@ -608,6 +631,8 @@ void kmem_cache_free(struct kmem_cache *c, void *b)
> } else {
> __kmem_cache_free(b, c->size);
> }
> +
> + kmemtrace_mark_free(KMEMTRACE_TYPE_CACHE, _RET_IP_, b);
> }
> EXPORT_SYMBOL(kmem_cache_free);
>

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/