[PATCH v3] tracing: add 'accounted' entry into output of allocation tracepoints

Vasily Averin
2022-05-18T06:25:01Z

Slab caches marked with SLAB_ACCOUNT force accounting for every
allocation from this cache even if __GFP_ACCOUNT flag is not passed.
Unfortunately, at the moment this flag is not visible in ftrace output,
and this makes it difficult to analyze the accounted allocations.

This patch adds boolean "allocated" entry into trace output,
and set it to 'true' for calls used __GFP_ACCOUNT flag and
for allocations from caches marked with SLAB_ACCOUNT.

Signed-off-by: Vasily Averin <vvs@openvz.org>
---
v3:
1) rework kmem_cache_alloc* tracepoints once again,
added struct kmem_cache argument into existing templates,
thanks to Matthew Wilcox
2) updated the corresponding ding trace_* calls
3) added boolean "allocated" entry into trace output,
thanks to Roman
4) updated patch subject and description

v2:
1) handle kmem_cache_alloc_node(), thanks to Shakeel
2) rework kmem_cache_alloc* tracepoints to use cachep instead
of current cachep->*size parameters.
NB: kmem_cache_alloc_node tracepoint in SLOB cannot use cachep,
and therefore it was replaced by kmalloc_node.
---
Now kmem tracing output looks like this:

kmem_cache_alloc: (getname_flags.part.0+0x2c) call_site=getname_flags.part.0+0x2c ptr=0xffff8fff022e9000 bytes_req=4096 bytes_alloc=4096 gfp_flags=GFP_KERNEL accounted=false
kmalloc: (alloc_bprm+0x32) call_site=alloc_bprm+0x32 ptr=0xffff8fff2b408a00 bytes_req=416 bytes_alloc=512 gfp_flags=GFP_KERNEL|__GFP_ZERO accounted=false
kmem_cache_alloc: (mm_alloc+0x16) call_site=mm_alloc+0x16 ptr=0xffff8fff0894d500 bytes_req=1048 bytes_alloc=1088 gfp_flags=GFP_KERNEL accounted=true
mm_page_alloc: page=0xffffffffa4ab8d42 pfn=0x12ad72 order=1 migratetype=0 gfp_flags=GFP_USER|__GFP_ZERO|__GFP_ACCOUNT
kmem_cache_alloc: (vm_area_alloc+0x1a) call_site=vm_area_alloc+0x1a ptr=0xffff8fff2af27000 bytes_req=200 bytes_alloc=200 gfp_flags=GFP_KERNEL accounted=true
---
include/trace/events/kmem.h | 38 +++++++++++++++++++++++--------------
mm/slab.c | 10 +++++-----
mm/slab_common.c | 9 ++++-----
mm/slob.c | 8 ++++----
mm/slub.c | 20 +++++++++----------
5 files changed, 47 insertions(+), 38 deletions(-)

diff --git a/include/trace/events/kmem.h b/include/trace/events/kmem.h
index 71c141804222..5bfeb6f276f1 100644
--- a/include/trace/events/kmem.h
+++ b/include/trace/events/kmem.h
@@ -13,11 +13,12 @@ DECLARE_EVENT_CLASS(kmem_alloc,

TP_PROTO(unsigned long call_site,
const void *ptr,
+ struct kmem_cache *s,
size_t bytes_req,
size_t bytes_alloc,
gfp_t gfp_flags),

- TP_ARGS(call_site, ptr, bytes_req, bytes_alloc, gfp_flags),
+ TP_ARGS(call_site, ptr, s, bytes_req, bytes_alloc, gfp_flags),

TP_STRUCT__entry(
__field( unsigned long, call_site )
@@ -25,6 +26,7 @@ DECLARE_EVENT_CLASS(kmem_alloc,
__field( size_t, bytes_req )
__field( size_t, bytes_alloc )
__field( unsigned long, gfp_flags )
+ __field( bool, accounted )
),

TP_fast_assign(
@@ -33,42 +35,46 @@ DECLARE_EVENT_CLASS(kmem_alloc,
__entry->bytes_req = bytes_req;
__entry->bytes_alloc = bytes_alloc;
__entry->gfp_flags = (__force unsigned long)gfp_flags;
+ __entry->accounted = (gfp_flags & __GFP_ACCOUNT) ||
+ (s && s->flags & SLAB_ACCOUNT);
),

- TP_printk("call_site=%pS ptr=%p bytes_req=%zu bytes_alloc=%zu gfp_flags=%s",
+ TP_printk("call_site=%pS ptr=%p bytes_req=%zu bytes_alloc=%zu gfp_flags=%s accounted=%s",
(void *)__entry->call_site,
__entry->ptr,
__entry->bytes_req,
__entry->bytes_alloc,
- show_gfp_flags(__entry->gfp_flags))
+ show_gfp_flags(__entry->gfp_flags),
+ __entry->accounted ? "true" : "false")
);

DEFINE_EVENT(kmem_alloc, kmalloc,

- TP_PROTO(unsigned long call_site, const void *ptr,
+ TP_PROTO(unsigned long call_site, const void *ptr, struct kmem_cache *s,
size_t bytes_req, size_t bytes_alloc, gfp_t gfp_flags),

- TP_ARGS(call_site, ptr, bytes_req, bytes_alloc, gfp_flags)
+ TP_ARGS(call_site, ptr, s, bytes_req, bytes_alloc, gfp_flags)
);

DEFINE_EVENT(kmem_alloc, kmem_cache_alloc,

- TP_PROTO(unsigned long call_site, const void *ptr,
+ TP_PROTO(unsigned long call_site, const void *ptr, struct kmem_cache *s,
size_t bytes_req, size_t bytes_alloc, gfp_t gfp_flags),

- TP_ARGS(call_site, ptr, bytes_req, bytes_alloc, gfp_flags)
+ TP_ARGS(call_site, ptr, s, bytes_req, bytes_alloc, gfp_flags)
);

DECLARE_EVENT_CLASS(kmem_alloc_node,

TP_PROTO(unsigned long call_site,
const void *ptr,
+ struct kmem_cache *s,
size_t bytes_req,
size_t bytes_alloc,
gfp_t gfp_flags,
int node),

- TP_ARGS(call_site, ptr, bytes_req, bytes_alloc, gfp_flags, node),
+ TP_ARGS(call_site, ptr, s, bytes_req, bytes_alloc, gfp_flags, node),

TP_STRUCT__entry(
__field( unsigned long, call_site )
@@ -77,6 +83,7 @@ DECLARE_EVENT_CLASS(kmem_alloc_node,
__field( size_t, bytes_alloc )
__field( unsigned long, gfp_flags )
__field( int, node )
+ __field( bool, accounted )
),

TP_fast_assign(
@@ -86,33 +93,36 @@ DECLARE_EVENT_CLASS(kmem_alloc_node,
__entry->bytes_alloc = bytes_alloc;
__entry->gfp_flags = (__force unsigned long)gfp_flags;
__entry->node = node;
+ __entry->accounted = (gfp_flags & __GFP_ACCOUNT) ||
+ (s && s->flags & SLAB_ACCOUNT);
),

- TP_printk("call_site=%pS ptr=%p bytes_req=%zu bytes_alloc=%zu gfp_flags=%s node=%d",
+ TP_printk("call_site=%pS ptr=%p bytes_req=%zu bytes_alloc=%zu gfp_flags=%s node=%d accounted=%s",
(void *)__entry->call_site,
__entry->ptr,
__entry->bytes_req,
__entry->bytes_alloc,
show_gfp_flags(__entry->gfp_flags),
- __entry->node)
+ __entry->node,
+ __entry->accounted ? "true" : "false")
);

DEFINE_EVENT(kmem_alloc_node, kmalloc_node,

TP_PROTO(unsigned long call_site, const void *ptr,
- size_t bytes_req, size_t bytes_alloc,
+ struct kmem_cache *s, size_t bytes_req, size_t bytes_alloc,
gfp_t gfp_flags, int node),

- TP_ARGS(call_site, ptr, bytes_req, bytes_alloc, gfp_flags, node)
+ TP_ARGS(call_site, ptr, s, bytes_req, bytes_alloc, gfp_flags, node)
);

DEFINE_EVENT(kmem_alloc_node, kmem_cache_alloc_node,

TP_PROTO(unsigned long call_site, const void *ptr,
- size_t bytes_req, size_t bytes_alloc,
+ struct kmem_cache *s, size_t bytes_req, size_t bytes_alloc,
gfp_t gfp_flags, int node),

- TP_ARGS(call_site, ptr, bytes_req, bytes_alloc, gfp_flags, node)
+ TP_ARGS(call_site, ptr, s, bytes_req, bytes_alloc, gfp_flags, node)
);

TRACE_EVENT(kfree,
diff --git a/mm/slab.c b/mm/slab.c
index 0edb474edef1..e5802445c7d6 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -3492,7 +3492,7 @@ void *__kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru,
{
void *ret = slab_alloc(cachep, lru, flags, cachep->object_size, _RET_IP_);

- trace_kmem_cache_alloc(_RET_IP_, ret,
+ trace_kmem_cache_alloc(_RET_IP_, ret, cachep,
cachep->object_size, cachep->size, flags);

return ret;
@@ -3581,7 +3581,7 @@ kmem_cache_alloc_trace(struct kmem_cache *cachep, gfp_t flags, size_t size)
ret = slab_alloc(cachep, NULL, flags, size, _RET_IP_);

ret = kasan_kmalloc(cachep, ret, size, flags);
- trace_kmalloc(_RET_IP_, ret,
+ trace_kmalloc(_RET_IP_, ret, cachep,
size, cachep->size, flags);
return ret;
}
@@ -3606,7 +3606,7 @@ void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid)
{
void *ret = slab_alloc_node(cachep, flags, nodeid, cachep->object_size, _RET_IP_);

- trace_kmem_cache_alloc_node(_RET_IP_, ret,
+ trace_kmem_cache_alloc_node(_RET_IP_, ret, cachep,
cachep->object_size, cachep->size,
flags, nodeid);

@@ -3625,7 +3625,7 @@ void *kmem_cache_alloc_node_trace(struct kmem_cache *cachep,
ret = slab_alloc_node(cachep, flags, nodeid, size, _RET_IP_);

ret = kasan_kmalloc(cachep, ret, size, flags);
- trace_kmalloc_node(_RET_IP_, ret,
+ trace_kmalloc_node(_RET_IP_, ret, cachep,
size, cachep->size,
flags, nodeid);
return ret;
@@ -3708,7 +3708,7 @@ static __always_inline void *__do_kmalloc(size_t size, gfp_t flags,
ret = slab_alloc(cachep, NULL, flags, size, caller);

ret = kasan_kmalloc(cachep, ret, size, flags);
- trace_kmalloc(caller, ret,
+ trace_kmalloc(caller, ret, cachep,
size, cachep->size, flags);

return ret;
diff --git a/mm/slab_common.c b/mm/slab_common.c
index 2b3206a2c3b5..a345e8600e00 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -25,13 +25,12 @@
#include <asm/page.h>
#include <linux/memcontrol.h>

-#define CREATE_TRACE_POINTS
-#include <trace/events/kmem.h>
-
#include "internal.h"
-
#include "slab.h"

+#define CREATE_TRACE_POINTS
+#include <trace/events/kmem.h>
+
enum slab_state slab_state;
LIST_HEAD(slab_caches);
DEFINE_MUTEX(slab_mutex);
@@ -967,7 +966,7 @@ EXPORT_SYMBOL(kmalloc_order);
void *kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order)
{
void *ret = kmalloc_order(size, flags, order);
- trace_kmalloc(_RET_IP_, ret, size, PAGE_SIZE << order, flags);
+ trace_kmalloc(_RET_IP_, ret, NULL, size, PAGE_SIZE << order, flags);
return ret;
}
EXPORT_SYMBOL(kmalloc_order_trace);
diff --git a/mm/slob.c b/mm/slob.c
index 40ea6e2d4ccd..dbefa0da0dfc 100644
--- a/mm/slob.c
+++ b/mm/slob.c
@@ -505,7 +505,7 @@ __do_kmalloc_node(size_t size, gfp_t gfp, int node, unsigned long caller)
*m = size;
ret = (void *)m + minalign;

- trace_kmalloc_node(caller, ret,
+ trace_kmalloc_node(caller, ret, NULL,
size, size + minalign, gfp, node);
} else {
unsigned int order = get_order(size);
@@ -514,7 +514,7 @@ __do_kmalloc_node(size_t size, gfp_t gfp, int node, unsigned long caller)
gfp |= __GFP_COMP;
ret = slob_new_pages(gfp, order, node);

- trace_kmalloc_node(caller, ret,
+ trace_kmalloc_node(caller, ret, NULL,
size, PAGE_SIZE << order, gfp, node);
}

@@ -610,12 +610,12 @@ static void *slob_alloc_node(struct kmem_cache *c, gfp_t flags, int node)

if (c->size < PAGE_SIZE) {
b = slob_alloc(c->size, flags, c->align, node, 0);
- trace_kmem_cache_alloc_node(_RET_IP_, b, c->object_size,
+ trace_kmem_cache_alloc_node(_RET_IP_, b, NULL, c->object_size,
SLOB_UNITS(c->size) * SLOB_UNIT,
flags, node);
} else {
b = slob_new_pages(flags, get_order(c->size), node);
- trace_kmem_cache_alloc_node(_RET_IP_, b, c->object_size,
+ trace_kmem_cache_alloc_node(_RET_IP_, b, NULL, c->object_size,
PAGE_SIZE << get_order(c->size),
flags, node);
}
diff --git a/mm/slub.c b/mm/slub.c
index ed5c2c03a47a..9b10591646dd 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -3231,7 +3231,7 @@ void *__kmem_cache_alloc_lru(struct kmem_cache *s, struct list_lru *lru,
{
void *ret = slab_alloc(s, lru, gfpflags, _RET_IP_, s->object_size);

- trace_kmem_cache_alloc(_RET_IP_, ret, s->object_size,
+ trace_kmem_cache_alloc(_RET_IP_, ret, s, s->object_size,
s->size, gfpflags);

return ret;
@@ -3254,7 +3254,7 @@ EXPORT_SYMBOL(kmem_cache_alloc_lru);
void *kmem_cache_alloc_trace(struct kmem_cache *s, gfp_t gfpflags, size_t size)
{
void *ret = slab_alloc(s, NULL, gfpflags, _RET_IP_, size);
- trace_kmalloc(_RET_IP_, ret, size, s->size, gfpflags);
+ trace_kmalloc(_RET_IP_, ret, s, size, s->size, gfpflags);
ret = kasan_kmalloc(s, ret, size, gfpflags);
return ret;
}
@@ -3266,7 +3266,7 @@ void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node)
{
void *ret = slab_alloc_node(s, NULL, gfpflags, node, _RET_IP_, s->object_size);

- trace_kmem_cache_alloc_node(_RET_IP_, ret,
+ trace_kmem_cache_alloc_node(_RET_IP_, ret, s,
s->object_size, s->size, gfpflags, node);

return ret;
@@ -3280,7 +3280,7 @@ void *kmem_cache_alloc_node_trace(struct kmem_cache *s,
{
void *ret = slab_alloc_node(s, NULL, gfpflags, node, _RET_IP_, size);

- trace_kmalloc_node(_RET_IP_, ret,
+ trace_kmalloc_node(_RET_IP_, ret, s,
size, s->size, gfpflags, node);

ret = kasan_kmalloc(s, ret, size, gfpflags);
@@ -4409,7 +4409,7 @@ void *__kmalloc(size_t size, gfp_t flags)

ret = slab_alloc(s, NULL, flags, _RET_IP_, size);

- trace_kmalloc(_RET_IP_, ret, size, s->size, flags);
+ trace_kmalloc(_RET_IP_, ret, s, size, s->size, flags);

ret = kasan_kmalloc(s, ret, size, flags);

@@ -4443,7 +4443,7 @@ void *__kmalloc_node(size_t size, gfp_t flags, int node)
if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) {
ret = kmalloc_large_node(size, flags, node);

- trace_kmalloc_node(_RET_IP_, ret,
+ trace_kmalloc_node(_RET_IP_, ret, NULL,
size, PAGE_SIZE << get_order(size),
flags, node);

@@ -4457,7 +4457,7 @@ void *__kmalloc_node(size_t size, gfp_t flags, int node)

ret = slab_alloc_node(s, NULL, flags, node, _RET_IP_, size);

- trace_kmalloc_node(_RET_IP_, ret, size, s->size, flags, node);
+ trace_kmalloc_node(_RET_IP_, ret, s, size, s->size, flags, node);

ret = kasan_kmalloc(s, ret, size, flags);

@@ -4916,7 +4916,7 @@ void *__kmalloc_track_caller(size_t size, gfp_t gfpflags, unsigned long caller)
ret = slab_alloc(s, NULL, gfpflags, caller, size);

/* Honor the call site pointer we received. */
- trace_kmalloc(caller, ret, size, s->size, gfpflags);
+ trace_kmalloc(caller, ret, s, size, s->size, gfpflags);

return ret;
}
@@ -4932,7 +4932,7 @@ void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags,
if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) {
ret = kmalloc_large_node(size, gfpflags, node);

- trace_kmalloc_node(caller, ret,
+ trace_kmalloc_node(caller, ret, NULL,
size, PAGE_SIZE << get_order(size),
gfpflags, node);

@@ -4947,7 +4947,7 @@ void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags,
ret = slab_alloc_node(s, NULL, gfpflags, node, caller, size);

/* Honor the call site pointer we received. */
- trace_kmalloc_node(caller, ret, size, s->size, gfpflags, node);
+ trace_kmalloc_node(caller, ret, s, size, s->size, gfpflags, node);

return ret;
}
--
2.31.1