Re: [PATCH 3/5] SLUB: Replace __builtin_return_address(0) with _RET_IP_.

Pekka J Enberg
2008-08-19T18:50:26Z

Eduard - Gabriel Munteanu wrote:
> > void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags)
> > {
> > - return slab_alloc(s, gfpflags, -1, __builtin_return_address(0));
> > + return slab_alloc(s, gfpflags, -1, (void *) _RET_IP_);
> > }

On Tue, 19 Aug 2008, Christoph Lameter wrote:
> Could you get rid of the casts by changing the type of parameter of slab_alloc()?

Yeah. How about something like this?

Pekka

>From f4d0f88f5b460afb2fd5dff75d4fcc0033e85a48 Mon Sep 17 00:00:00 2001
From: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Date: Tue, 19 Aug 2008 20:43:25 +0300
Subject: [PATCH] SLUB: Replace __builtin_return_address(0) with _RET_IP_.

This patch replaces __builtin_return_address(0) with _RET_IP_, since a
previous patch moved _RET_IP_ and _THIS_IP_ to include/linux/kernel.h and
they're widely available now. This makes for shorter and easier to read
code.

[penberg@cs.helsinki.fi: remove _RET_IP_ casts to void pointer]
Signed-off-by: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
---
include/linux/slab.h | 4 ++--
mm/slab.c | 8 ++++----
mm/slub.c | 44 ++++++++++++++++++++++----------------------
3 files changed, 28 insertions(+), 28 deletions(-)

diff --git a/include/linux/slab.h b/include/linux/slab.h
index 5ff9676..5ebb8df 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -225,7 +225,7 @@ static inline void *kmem_cache_alloc_node(struct kmem_cache *cachep,
* request comes from.
*/
#if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB)
-extern void *__kmalloc_track_caller(size_t, gfp_t, void*);
+extern void *__kmalloc_track_caller(size_t, gfp_t, unsigned long);
#define kmalloc_track_caller(size, flags) \
__kmalloc_track_caller(size, flags, __builtin_return_address(0))
#else
@@ -243,7 +243,7 @@ extern void *__kmalloc_track_caller(size_t, gfp_t, void*);
* allocation request comes from.
*/
#if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB)
-extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, void *);
+extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, unsigned long);
#define kmalloc_node_track_caller(size, flags, node) \
__kmalloc_node_track_caller(size, flags, node, \
__builtin_return_address(0))
diff --git a/mm/slab.c b/mm/slab.c
index e76eee4..6a0e633 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -3685,9 +3685,9 @@ void *__kmalloc_node(size_t size, gfp_t flags, int node)
EXPORT_SYMBOL(__kmalloc_node);

void *__kmalloc_node_track_caller(size_t size, gfp_t flags,
- int node, void *caller)
+ int node, unsigned long caller)
{
- return __do_kmalloc_node(size, flags, node, caller);
+ return __do_kmalloc_node(size, flags, node, (void *)caller);
}
EXPORT_SYMBOL(__kmalloc_node_track_caller);
#else
@@ -3729,9 +3729,9 @@ void *__kmalloc(size_t size, gfp_t flags)
}
EXPORT_SYMBOL(__kmalloc);

-void *__kmalloc_track_caller(size_t size, gfp_t flags, void *caller)
+void *__kmalloc_track_caller(size_t size, gfp_t flags, unsigned long caller)
{
- return __do_kmalloc(size, flags, caller);
+ return __do_kmalloc(size, flags, (void *)caller);
}
EXPORT_SYMBOL(__kmalloc_track_caller);

diff --git a/mm/slub.c b/mm/slub.c
index 4f5b961..804ca82 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -177,7 +177,7 @@ static LIST_HEAD(slab_caches);
* Tracking user of a slab.
*/
struct track {
- void *addr; /* Called from address */
+ unsigned long addr; /* Called from address */
int cpu; /* Was running on cpu */
int pid; /* Pid context */
unsigned long when; /* When did the operation occur */
@@ -366,7 +366,7 @@ static struct track *get_track(struct kmem_cache *s, void *object,
}

static void set_track(struct kmem_cache *s, void *object,
- enum track_item alloc, void *addr)
+ enum track_item alloc, unsigned long addr)
{
struct track *p;

@@ -390,8 +390,8 @@ static void init_tracking(struct kmem_cache *s, void *object)
if (!(s->flags & SLAB_STORE_USER))
return;

- set_track(s, object, TRACK_FREE, NULL);
- set_track(s, object, TRACK_ALLOC, NULL);
+ set_track(s, object, TRACK_FREE, 0);
+ set_track(s, object, TRACK_ALLOC, 0);
}

static void print_track(const char *s, struct track *t)
@@ -400,7 +400,7 @@ static void print_track(const char *s, struct track *t)
return;

printk(KERN_ERR "INFO: %s in %pS age=%lu cpu=%u pid=%d\n",
- s, t->addr, jiffies - t->when, t->cpu, t->pid);
+ s, (void *)t->addr, jiffies - t->when, t->cpu, t->pid);
}

static void print_tracking(struct kmem_cache *s, void *object)
@@ -865,7 +865,7 @@ static void setup_object_debug(struct kmem_cache *s, struct page *page,
}

static int alloc_debug_processing(struct kmem_cache *s, struct page *page,
- void *object, void *addr)
+ void *object, unsigned long addr)
{
if (!check_slab(s, page))
goto bad;
@@ -905,7 +905,7 @@ bad:
}

static int free_debug_processing(struct kmem_cache *s, struct page *page,
- void *object, void *addr)
+ void *object, unsigned long addr)
{
if (!check_slab(s, page))
goto fail;
@@ -1498,8 +1498,8 @@ static inline int node_match(struct kmem_cache_cpu *c, int node)
* we need to allocate a new slab. This is the slowest path since it involves
* a call to the page allocator and the setup of a new slab.
*/
-static void *__slab_alloc(struct kmem_cache *s,
- gfp_t gfpflags, int node, void *addr, struct kmem_cache_cpu *c)
+static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
+ unsigned long addr, struct kmem_cache_cpu *c)
{
void **object;
struct page *new;
@@ -1583,7 +1583,7 @@ debug:
* Otherwise we can simply pick the next object from the lockless free list.
*/
static __always_inline void *slab_alloc(struct kmem_cache *s,
- gfp_t gfpflags, int node, void *addr)
+ gfp_t gfpflags, int node, unsigned long addr)
{
void **object;
struct kmem_cache_cpu *c;
@@ -1612,14 +1612,14 @@ static __always_inline void *slab_alloc(struct kmem_cache *s,

void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags)
{
- return slab_alloc(s, gfpflags, -1, __builtin_return_address(0));
+ return slab_alloc(s, gfpflags, -1, _RET_IP_);
}
EXPORT_SYMBOL(kmem_cache_alloc);

#ifdef CONFIG_NUMA
void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node)
{
- return slab_alloc(s, gfpflags, node, __builtin_return_address(0));
+ return slab_alloc(s, gfpflags, node, _RET_IP_);
}
EXPORT_SYMBOL(kmem_cache_alloc_node);
#endif
@@ -1633,7 +1633,7 @@ EXPORT_SYMBOL(kmem_cache_alloc_node);
* handling required then we can return immediately.
*/
static void __slab_free(struct kmem_cache *s, struct page *page,
- void *x, void *addr, unsigned int offset)
+ void *x, unsigned long addr, unsigned int offset)
{
void *prior;
void **object = (void *)x;
@@ -1703,7 +1703,7 @@ debug:
* with all sorts of special processing.
*/
static __always_inline void slab_free(struct kmem_cache *s,
- struct page *page, void *x, void *addr)
+ struct page *page, void *x, unsigned long addr)
{
void **object = (void *)x;
struct kmem_cache_cpu *c;
@@ -1730,7 +1730,7 @@ void kmem_cache_free(struct kmem_cache *s, void *x)

page = virt_to_head_page(x);

- slab_free(s, page, x, __builtin_return_address(0));
+ slab_free(s, page, x, _RET_IP_);
}
EXPORT_SYMBOL(kmem_cache_free);

@@ -2657,7 +2657,7 @@ void *__kmalloc(size_t size, gfp_t flags)
if (unlikely(ZERO_OR_NULL_PTR(s)))
return s;

- return slab_alloc(s, flags, -1, __builtin_return_address(0));
+ return slab_alloc(s, flags, -1, _RET_IP_);
}
EXPORT_SYMBOL(__kmalloc);

@@ -2685,7 +2685,7 @@ void *__kmalloc_node(size_t size, gfp_t flags, int node)
if (unlikely(ZERO_OR_NULL_PTR(s)))
return s;

- return slab_alloc(s, flags, node, __builtin_return_address(0));
+ return slab_alloc(s, flags, node, _RET_IP_);
}
EXPORT_SYMBOL(__kmalloc_node);
#endif
@@ -2742,7 +2742,7 @@ void kfree(const void *x)
put_page(page);
return;
}
- slab_free(page->slab, page, object, __builtin_return_address(0));
+ slab_free(page->slab, page, object, _RET_IP_);
}
EXPORT_SYMBOL(kfree);

@@ -3198,7 +3198,7 @@ static struct notifier_block __cpuinitdata slab_notifier = {

#endif

-void *__kmalloc_track_caller(size_t size, gfp_t gfpflags, void *caller)
+void *__kmalloc_track_caller(size_t size, gfp_t gfpflags, unsigned long caller)
{
struct kmem_cache *s;

@@ -3214,7 +3214,7 @@ void *__kmalloc_track_caller(size_t size, gfp_t gfpflags, void *caller)
}

void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags,
- int node, void *caller)
+ int node, unsigned long caller)
{
struct kmem_cache *s;

@@ -3425,7 +3425,7 @@ static void resiliency_test(void) {};

struct location {
unsigned long count;
- void *addr;
+ unsigned long addr;
long long sum_time;
long min_time;
long max_time;
@@ -3473,7 +3473,7 @@ static int add_location(struct loc_track *t, struct kmem_cache *s,
{
long start, end, pos;
struct location *l;
- void *caddr;
+ unsigned long caddr;
unsigned long age = jiffies - track->when;

start = -1;
--
1.5.4.3