tracing: Define kmem_trace_alloc_notrace unconditionally

For slab, if CONFIG_KMEMTRACE and CONFIG_DEBUG_SLAB are not set, __do_kmalloc() will not track callers:

 # ./perf record -f -a -R -e kmem:kmalloc
 ^C
 # ./perf trace
 ...
          perf-2204  [000]   147.376774: kmalloc: call_site=c0529d2d ...
          perf-2204  [000]   147.400997: kmalloc: call_site=c0529d2d ...
          Xorg-1461  [001]   147.405413: kmalloc: call_site=0 ...
          Xorg-1461  [001]   147.405609: kmalloc: call_site=0 ...
       konsole-1776  [001]   147.405786: kmalloc: call_site=0 ...

Signed-off-by Li Zefan <[email protected]>

---
 mm/slab.c |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

mm/slab.c +3 -3

index e556380..eacf7f0 100644
@@ -3637,7 +3637,7 @@ __do_kmalloc_node(size_t size, gfp_t flags, int node, void *caller)
 	return ret;
 }
 
-#if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_KMEMTRACE)
+#if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_TRACING)
 void *__kmalloc_node(size_t size, gfp_t flags, int node)
 {
 	return __do_kmalloc_node(size, flags, node,

@@ -3657,7 +3657,7 @@ void *__kmalloc_node(size_t size, gfp_t flags, int node)
 	return __do_kmalloc_node(size, flags, node, NULL);
 }
 EXPORT_SYMBOL(__kmalloc_node);
-#endif /* CONFIG_DEBUG_SLAB */
+#endif /* CONFIG_DEBUG_SLAB || CONFIG_TRACING */
 #endif /* CONFIG_NUMA */
 
 /**

@@ -3689,7 +3689,7 @@ static __always_inline void *__do_kmalloc(size_t size, gfp_t flags,
 }
 
 
-#if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_KMEMTRACE)
+#if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_TRACING)
 void *__kmalloc(size_t size, gfp_t flags)
 {
 	return __do_kmalloc(size, flags, __builtin_return_address(0));

Always define kmem_trace_alloc_{,node}_notrace(), otherwise perf-kmem will show wrong stats ifndef CONFIG_KMEMTRACE, because a kmalloc() memory allocation may be traced by both trace_kmalloc() and trace_kmem_cache_alloc().

Signed-off-by Li Zefan <[email protected]>

---
 include/linux/slab_def.h |   24 ++----------------------
 include/linux/slub_def.h |   27 +++------------------------
 mm/slab.c                |   12 ------------
 mm/slub.c                |    4 ----
 4 files changed, 5 insertions(+), 62 deletions(-)

include/linux/slab_def.h +2 -22

index 850d057..1c9ce4b 100644
@@ -109,21 +109,12 @@ extern struct cache_sizes malloc_sizes[];
 
 void *kmem_cache_alloc(struct kmem_cache *, gfp_t);
 void *__kmalloc(size_t size, gfp_t flags);
+void *kmem_cache_alloc_notrace(struct kmem_cache *cachep, gfp_t flags);
 
-#ifdef CONFIG_KMEMTRACE
-extern void *kmem_cache_alloc_notrace(struct kmem_cache *cachep, gfp_t flags);
-extern size_t slab_buffer_size(struct kmem_cache *cachep);
-#else
-static __always_inline void *
-kmem_cache_alloc_notrace(struct kmem_cache *cachep, gfp_t flags)
-{
-	return kmem_cache_alloc(cachep, flags);
-}
 static inline size_t slab_buffer_size(struct kmem_cache *cachep)
 {
-	return 0;
+	return cachep->buffer_size;
 }
-#endif
 
 static __always_inline void *kmalloc(size_t size, gfp_t flags)
 {

@@ -165,20 +156,9 @@ found:
 #ifdef CONFIG_NUMA
 extern void *__kmalloc_node(size_t size, gfp_t flags, int node);
 extern void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
-
-#ifdef CONFIG_KMEMTRACE
 extern void *kmem_cache_alloc_node_notrace(struct kmem_cache *cachep,
 					   gfp_t flags,
 					   int nodeid);
-#else
-static __always_inline void *
-kmem_cache_alloc_node_notrace(struct kmem_cache *cachep,
-			      gfp_t flags,
-			      int nodeid)
-{
-	return kmem_cache_alloc_node(cachep, flags, nodeid);
-}
-#endif
 
 static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
 {

include/linux/slub_def.h +3 -24

index 5ad70a6..5c5ca0c 100644
@@ -215,18 +215,9 @@ static __always_inline struct kmem_cache *kmalloc_slab(size_t size)
 #endif
 
 void *kmem_cache_alloc(struct kmem_cache *, gfp_t);
+void *kmem_cache_alloc_notrace(struct kmem_cache *s, gfp_t gfpflags);
 void *__kmalloc(size_t size, gfp_t flags);
 
-#ifdef CONFIG_KMEMTRACE
-extern void *kmem_cache_alloc_notrace(struct kmem_cache *s, gfp_t gfpflags);
-#else
-static __always_inline void *
-kmem_cache_alloc_notrace(struct kmem_cache *s, gfp_t gfpflags)
-{
-	return kmem_cache_alloc(s, gfpflags);
-}
-#endif
-
 static __always_inline void *kmalloc_large(size_t size, gfp_t flags)
 {
 	unsigned int order = get_order(size);

@@ -265,20 +256,8 @@ static __always_inline void *kmalloc(size_t size, gfp_t flags)
 #ifdef CONFIG_NUMA
 void *__kmalloc_node(size_t size, gfp_t flags, int node);
 void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
-
-#ifdef CONFIG_KMEMTRACE
-extern void *kmem_cache_alloc_node_notrace(struct kmem_cache *s,
-					   gfp_t gfpflags,
-					   int node);
-#else
-static __always_inline void *
-kmem_cache_alloc_node_notrace(struct kmem_cache *s,
-			      gfp_t gfpflags,
-			      int node)
-{
-	return kmem_cache_alloc_node(s, gfpflags, node);
-}
-#endif
+void *kmem_cache_alloc_node_notrace(struct kmem_cache *s, gfp_t gfpflags,
+				    int node);
 
 static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
 {

mm/slab.c +0 -12

index 7dfa481..e556380 100644
@@ -490,14 +490,6 @@ static void **dbg_userword(struct kmem_cache *cachep, void *objp)
 
 #endif
 
-#ifdef CONFIG_KMEMTRACE
-size_t slab_buffer_size(struct kmem_cache *cachep)
-{
-	return cachep->buffer_size;
-}
-EXPORT_SYMBOL(slab_buffer_size);
-#endif
-
 /*
  * Do not go above this order unless 0 objects fit into the slab.
  */

@@ -3558,13 +3550,11 @@ void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags)
 }
 EXPORT_SYMBOL(kmem_cache_alloc);
 
-#ifdef CONFIG_KMEMTRACE
 void *kmem_cache_alloc_notrace(struct kmem_cache *cachep, gfp_t flags)
 {
 	return __cache_alloc(cachep, flags, __builtin_return_address(0));
 }
 EXPORT_SYMBOL(kmem_cache_alloc_notrace);
-#endif
 
 /**
  * kmem_ptr_validate - check if an untrusted pointer might be a slab entry.

@@ -3621,7 +3611,6 @@ void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid)
 }
 EXPORT_SYMBOL(kmem_cache_alloc_node);
 
-#ifdef CONFIG_KMEMTRACE
 void *kmem_cache_alloc_node_notrace(struct kmem_cache *cachep,
 				    gfp_t flags,
 				    int nodeid)

@@ -3630,7 +3619,6 @@ void *kmem_cache_alloc_node_notrace(struct kmem_cache *cachep,
 				  __builtin_return_address(0));
 }
 EXPORT_SYMBOL(kmem_cache_alloc_node_notrace);
-#endif
 
 static __always_inline void *
 __do_kmalloc_node(size_t size, gfp_t flags, int node, void *caller)

mm/slub.c +0 -4

index 4996fc7..a1c8fe5 100644
@@ -1754,13 +1754,11 @@ void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags)
 }
 EXPORT_SYMBOL(kmem_cache_alloc);
 
-#ifdef CONFIG_KMEMTRACE
 void *kmem_cache_alloc_notrace(struct kmem_cache *s, gfp_t gfpflags)
 {
 	return slab_alloc(s, gfpflags, -1, _RET_IP_);
 }
 EXPORT_SYMBOL(kmem_cache_alloc_notrace);
-#endif
 
 #ifdef CONFIG_NUMA
 void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node)

@@ -1775,7 +1773,6 @@ void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node)
 EXPORT_SYMBOL(kmem_cache_alloc_node);
 #endif
 
-#ifdef CONFIG_KMEMTRACE
 void *kmem_cache_alloc_node_notrace(struct kmem_cache *s,
 				    gfp_t gfpflags,
 				    int node)

@@ -1783,7 +1780,6 @@ void *kmem_cache_alloc_node_notrace(struct kmem_cache *s,
 	return slab_alloc(s, gfpflags, node, _RET_IP_);
 }
 EXPORT_SYMBOL(kmem_cache_alloc_node_notrace);
-#endif
 
 /*
  * Slow patch handling. This may still be called frequently since objects

Quoted 6 lines · Li Zefan

Always define kmem_trace_alloc_{,node}_notrace(), otherwise perf-kmem will show wrong stats ifndef CONFIG_KMEMTRACE, because a kmalloc() memory allocation may be traced by both trace_kmalloc() and trace_kmem_cache_alloc().

Signed-off-by Li Zefan <[email protected]>

Did you check how much this will make kernel text bigger because of the inlining happening in kmem_cache_alloc_notrace()?

Quoted 204 lines

---
 include/linux/slab_def.h |   24 ++----------------------
 include/linux/slub_def.h |   27 +++------------------------
 mm/slab.c                |   12 ------------
 mm/slub.c                |    4 ----
 4 files changed, 5 insertions(+), 62 deletions(-)

include/linux/slab_def.h +2 -11

index 850d057..1c9ce4b 100644
@@ -109,21 +109,12 @@ extern struct cache_sizes malloc_sizes[];
 
 void *kmem_cache_alloc(struct kmem_cache *, gfp_t);
 void *__kmalloc(size_t size, gfp_t flags);
+void *kmem_cache_alloc_notrace(struct kmem_cache *cachep, gfp_t flags);
 
-#ifdef CONFIG_KMEMTRACE
-extern void *kmem_cache_alloc_notrace(struct kmem_cache *cachep, 
 gfp_t flags);
-extern size_t slab_buffer_size(struct kmem_cache *cachep);
-#else
-static __always_inline void *
-kmem_cache_alloc_notrace(struct kmem_cache *cachep, gfp_t flags)
-{
-    return kmem_cache_alloc(cachep, flags);
-}
 static inline size_t slab_buffer_size(struct kmem_cache *cachep)
 {
-    return 0;
+    return cachep->buffer_size;
 }
-#endif
 
 static __always_inline void *kmalloc(size_t size, gfp_t flags)

{

include/linux/slab_def.h +0 -11

@@ -165,20 +156,9 @@ found:
 #ifdef CONFIG_NUMA
 extern void *__kmalloc_node(size_t size, gfp_t flags, int node);
 extern void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, 
 int node);
-
-#ifdef CONFIG_KMEMTRACE
 extern void *kmem_cache_alloc_node_notrace(struct kmem_cache *cachep,
                        gfp_t flags,
                        int nodeid);
-#else
-static __always_inline void *
-kmem_cache_alloc_node_notrace(struct kmem_cache *cachep,
-                  gfp_t flags,
-                  int nodeid)
-{
-    return kmem_cache_alloc_node(cachep, flags, nodeid);
-}
-#endif
 
 static __always_inline void *kmalloc_node(size_t size, gfp_t flags, 

int node)
{

include/linux/slub_def.h +1 -10

index 5ad70a6..5c5ca0c 100644
@@ -215,18 +215,9 @@ static __always_inline struct kmem_cache 
 *kmalloc_slab(size_t size)
 #endif
 
 void *kmem_cache_alloc(struct kmem_cache *, gfp_t);
+void *kmem_cache_alloc_notrace(struct kmem_cache *s, gfp_t gfpflags);
 void *__kmalloc(size_t size, gfp_t flags);
 
-#ifdef CONFIG_KMEMTRACE
-extern void *kmem_cache_alloc_notrace(struct kmem_cache *s, gfp_t 
 gfpflags);
-#else
-static __always_inline void *
-kmem_cache_alloc_notrace(struct kmem_cache *s, gfp_t gfpflags)
-{
-    return kmem_cache_alloc(s, gfpflags);
-}
-#endif
-
 static __always_inline void *kmalloc_large(size_t size, gfp_t flags)

 {
     unsigned int order = get_order(size);

include/linux/slub_def.h +2 -14

@@ -265,20 +256,8 @@ static __always_inline void *kmalloc(size_t size, 
 gfp_t flags)
 #ifdef CONFIG_NUMA
 void *__kmalloc_node(size_t size, gfp_t flags, int node);
 void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
-
-#ifdef CONFIG_KMEMTRACE
-extern void *kmem_cache_alloc_node_notrace(struct kmem_cache *s,
-                       gfp_t gfpflags,
-                       int node);
-#else
-static __always_inline void *
-kmem_cache_alloc_node_notrace(struct kmem_cache *s,
-                  gfp_t gfpflags,
-                  int node)
-{
-    return kmem_cache_alloc_node(s, gfpflags, node);
-}
-#endif
+void *kmem_cache_alloc_node_notrace(struct kmem_cache *s, gfp_t 
 gfpflags,
+                    int node);
 

static __always_inline void *kmalloc_node(size_t size, gfp_t flags,
int node)
{

mm/slab.c +0 -8

index 7dfa481..e556380 100644
@@ -490,14 +490,6 @@ static void **dbg_userword(struct kmem_cache 
 *cachep, void *objp)
 
 #endif
 
-#ifdef CONFIG_KMEMTRACE
-size_t slab_buffer_size(struct kmem_cache *cachep)
-{
-    return cachep->buffer_size;
-}
-EXPORT_SYMBOL(slab_buffer_size);
-#endif
-
 /*
  * Do not go above this order unless 0 objects fit into the slab.

*/

mm/slab.c +0 -2

@@ -3558,13 +3550,11 @@ void *kmem_cache_alloc(struct kmem_cache 
 *cachep, gfp_t flags)
 }
 EXPORT_SYMBOL(kmem_cache_alloc);
 
-#ifdef CONFIG_KMEMTRACE
 void *kmem_cache_alloc_notrace(struct kmem_cache *cachep, gfp_t flags)
 {
     return __cache_alloc(cachep, flags, __builtin_return_address(0));
 }
 EXPORT_SYMBOL(kmem_cache_alloc_notrace);
-#endif
 
 /**

* kmem_ptr_validate - check if an untrusted pointer might be a slab
entry.

mm/slab.c +0 -1

@@ -3621,7 +3611,6 @@ void *kmem_cache_alloc_node(struct kmem_cache 
 *cachep, gfp_t flags, int nodeid)
 }
 EXPORT_SYMBOL(kmem_cache_alloc_node);
 
-#ifdef CONFIG_KMEMTRACE
 void *kmem_cache_alloc_node_notrace(struct kmem_cache *cachep,
                     gfp_t flags,

int nodeid)

mm/slab.c +0 -1

@@ -3630,7 +3619,6 @@ void *kmem_cache_alloc_node_notrace(struct 
 kmem_cache *cachep,
                   __builtin_return_address(0));
 }
 EXPORT_SYMBOL(kmem_cache_alloc_node_notrace);
-#endif
 
 static __always_inline void *

__do_kmalloc_node(size_t size, gfp_t flags, int node, void *caller)

mm/slub.c +0 -2

index 4996fc7..a1c8fe5 100644
@@ -1754,13 +1754,11 @@ void *kmem_cache_alloc(struct kmem_cache *s, 
 gfp_t gfpflags)
 }
 EXPORT_SYMBOL(kmem_cache_alloc);
 
-#ifdef CONFIG_KMEMTRACE
 void *kmem_cache_alloc_notrace(struct kmem_cache *s, gfp_t gfpflags)
 {
     return slab_alloc(s, gfpflags, -1, _RET_IP_);
 }
 EXPORT_SYMBOL(kmem_cache_alloc_notrace);
-#endif
 
 #ifdef CONFIG_NUMA

void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int
node)

mm/slub.c +0 -1

@@ -1775,7 +1773,6 @@ void *kmem_cache_alloc_node(struct kmem_cache 
 *s, gfp_t gfpflags, int node)
 EXPORT_SYMBOL(kmem_cache_alloc_node);
 #endif
 
-#ifdef CONFIG_KMEMTRACE
 void *kmem_cache_alloc_node_notrace(struct kmem_cache *s,
                     gfp_t gfpflags,

int node)

mm/slub.c +0 -1

@@ -1783,7 +1780,6 @@ void *kmem_cache_alloc_node_notrace(struct 
 kmem_cache *s,
     return slab_alloc(s, gfpflags, node, _RET_IP_);
 }
 EXPORT_SYMBOL(kmem_cache_alloc_node_notrace);
-#endif
 
 /*

* Slow patch handling. This may still be called frequently since
objects

Quoted 6 lines · Pekka Enberg

Quoted 5 lines · Li Zefan

Always define kmem_trace_alloc_{,node}_notrace(), otherwise perf-kmem will show wrong stats ifndef CONFIG_KMEMTRACE, because a kmalloc() memory allocation may be traced by both trace_kmalloc() and trace_kmem_cache_alloc().

Quoted 4 lines

Quoted 1 line

Signed-off-by Li Zefan <[email protected]>

Did you check how much this will make kernel text bigger because of the inlining happening in kmem_cache_alloc_notrace()?

Maybe use CONFIG_TRACING instead of CONFIG_KMEMTRACE here like in the other patch?

Quoted 10 lines · Pekka Enberg

Quoted 9 lines · Pekka Enberg

Quoted 6 lines · Li Zefan

Always define kmem_trace_alloc_{,node}_notrace(), otherwise perf-kmem will show wrong stats ifndef CONFIG_KMEMTRACE, because a kmalloc() memory allocation may be traced by both trace_kmalloc() and trace_kmem_cache_alloc().

Signed-off-by Li Zefan <[email protected]>

Did you check how much this will make kernel text bigger because of the inlining happening in kmem_cache_alloc_notrace()?

Quoted 3 lines

Maybe use CONFIG_TRACING instead of CONFIG_KMEMTRACE here like in the other patch?

Wouldn't removing CONFIG_KMEMTRACE make the code cleaner? Anyway, if CONFIG_TRACING is not enabled, all the trace_xxx() will be turned into no-op.

Quoted 6 lines · Li Zefan

Always define kmem_trace_alloc_{,node}_notrace(), otherwise perf-kmem will show wrong stats ifndef CONFIG_KMEMTRACE, because a kmalloc() memory allocation may be traced by both trace_kmalloc() and trace_kmem_cache_alloc().

Signed-off-by Li Zefan <[email protected]>

Did you check how much this will make kernel text bigger because of the inlining happening in kmem_cache_alloc_notrace()?

Quoted 6 lines · Pekka Enberg

Quoted 5 lines · Li Zefan

Always define kmem_trace_alloc_{,node}_notrace(), otherwise perf-kmem will show wrong stats ifndef CONFIG_KMEMTRACE, because a kmalloc() memory allocation may be traced by both trace_kmalloc() and trace_kmem_cache_alloc().

Quoted 4 lines

Quoted 1 line

Signed-off-by Li Zefan <[email protected]>

Did you check how much this will make kernel text bigger because of the inlining happening in kmem_cache_alloc_notrace()?

I'm not sure I understood what you meant, but I'm not inlining kmem_cache_alloc_notrace(), and instead I'm removing the inline version in !CONFIG_KMEMTRACE case.

Quoted 10 lines

Quoted 9 lines

Quoted 6 lines

Always define kmem_trace_alloc_{,node}_notrace(), otherwise perf-kmem will show wrong stats ifndef CONFIG_KMEMTRACE, because a kmalloc() memory allocation may be traced by both trace_kmalloc() and trace_kmem_cache_alloc().

Signed-off-by Li Zefan <[email protected]>

Did you check how much this will make kernel text bigger because of the inlining happening in kmem_cache_alloc_notrace()?

Quoted 3 lines

I'm not sure I understood what you meant, but I'm not inlining kmem_cache_alloc_notrace(), and instead I'm removing the inline version in !CONFIG_KMEMTRACE case.

In SLUB, slab_alloc() will be inlined to kmem_cache_alloc_notrace() increasing mm/slub.o size so we don't want to define kmem_cache_alloc_notrace() unconditionally.