* [PATCH 1/2] perf callchain: Make callchain cursors TLS
@ 2012-05-31 5:43 Namhyung Kim
2012-05-31 5:43 ` [PATCH/RFC 2/2] perf tools: Check callchain is corrupted Namhyung Kim
` (2 more replies)
0 siblings, 3 replies; 9+ messages in thread
From: Namhyung Kim @ 2012-05-31 5:43 UTC (permalink / raw)
To: Arnaldo Carvalho de Melo
Cc: Peter Zijlstra, Paul Mackerras, Ingo Molnar, Namhyung Kim, LKML,
Sunjin Yang
perf top -G has a race on callchain cursor between main
thread and display thread. Since the callchain cursors
are used locally make them thread-local data would solve
the problem.
Reported-by: Sunjin Yang <fan4326@gmail.com>
Suggested-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
---
tools/perf/builtin-report.c | 2 +-
tools/perf/builtin-top.c | 2 +-
tools/perf/util/callchain.c | 2 ++
tools/perf/util/callchain.h | 2 ++
tools/perf/util/hist.c | 7 ++++---
tools/perf/util/hist.h | 2 --
tools/perf/util/session.c | 14 +++++++-------
7 files changed, 17 insertions(+), 14 deletions(-)
diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index d58e41445d0d..159ca6435788 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -152,7 +152,7 @@ static int perf_evsel__add_hist_entry(struct perf_evsel *evsel,
if (symbol_conf.use_callchain) {
err = callchain_append(he->callchain,
- &evsel->hists.callchain_cursor,
+ &callchain_cursor,
sample->period);
if (err)
return err;
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 6031dce0429f..ea7b600dc652 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -787,7 +787,7 @@ static void perf_event__process_sample(struct perf_tool *tool,
}
if (symbol_conf.use_callchain) {
- err = callchain_append(he->callchain, &evsel->hists.callchain_cursor,
+ err = callchain_append(he->callchain, &callchain_cursor,
sample->period);
if (err)
return;
diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c
index 9f7106a8d9a4..3a6bff47614f 100644
--- a/tools/perf/util/callchain.c
+++ b/tools/perf/util/callchain.c
@@ -18,6 +18,8 @@
#include "util.h"
#include "callchain.h"
+__thread struct callchain_cursor callchain_cursor;
+
bool ip_callchain__valid(struct ip_callchain *chain,
const union perf_event *event)
{
diff --git a/tools/perf/util/callchain.h b/tools/perf/util/callchain.h
index 7f9c0f1ae3a9..3bdb407f9cd9 100644
--- a/tools/perf/util/callchain.h
+++ b/tools/perf/util/callchain.h
@@ -76,6 +76,8 @@ struct callchain_cursor {
struct callchain_cursor_node *curr;
};
+extern __thread struct callchain_cursor callchain_cursor;
+
static inline void callchain_init(struct callchain_root *root)
{
INIT_LIST_HEAD(&root->node.siblings);
diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
index 1293b5ebea4d..514e2a4b367d 100644
--- a/tools/perf/util/hist.c
+++ b/tools/perf/util/hist.c
@@ -378,7 +378,7 @@ void hist_entry__free(struct hist_entry *he)
* collapse the histogram
*/
-static bool hists__collapse_insert_entry(struct hists *hists,
+static bool hists__collapse_insert_entry(struct hists *hists __used,
struct rb_root *root,
struct hist_entry *he)
{
@@ -397,8 +397,9 @@ static bool hists__collapse_insert_entry(struct hists *hists,
iter->period += he->period;
iter->nr_events += he->nr_events;
if (symbol_conf.use_callchain) {
- callchain_cursor_reset(&hists->callchain_cursor);
- callchain_merge(&hists->callchain_cursor, iter->callchain,
+ callchain_cursor_reset(&callchain_cursor);
+ callchain_merge(&callchain_cursor,
+ iter->callchain,
he->callchain);
}
hist_entry__free(he);
diff --git a/tools/perf/util/hist.h b/tools/perf/util/hist.h
index cfc64e293f90..34bb556d6219 100644
--- a/tools/perf/util/hist.h
+++ b/tools/perf/util/hist.h
@@ -67,8 +67,6 @@ struct hists {
struct events_stats stats;
u64 event_stream;
u16 col_len[HISTC_NR_COLS];
- /* Best would be to reuse the session callchain cursor */
- struct callchain_cursor callchain_cursor;
};
struct hist_entry *__hists__add_entry(struct hists *self,
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 93d355d27109..4eed171d275d 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -288,7 +288,8 @@ struct branch_info *machine__resolve_bstack(struct machine *self,
return bi;
}
-int machine__resolve_callchain(struct machine *self, struct perf_evsel *evsel,
+int machine__resolve_callchain(struct machine *self,
+ struct perf_evsel *evsel __used,
struct thread *thread,
struct ip_callchain *chain,
struct symbol **parent)
@@ -297,7 +298,7 @@ int machine__resolve_callchain(struct machine *self, struct perf_evsel *evsel,
unsigned int i;
int err;
- callchain_cursor_reset(&evsel->hists.callchain_cursor);
+ callchain_cursor_reset(&callchain_cursor);
for (i = 0; i < chain->nr; i++) {
u64 ip;
@@ -333,7 +334,7 @@ int machine__resolve_callchain(struct machine *self, struct perf_evsel *evsel,
break;
}
- err = callchain_cursor_append(&evsel->hists.callchain_cursor,
+ err = callchain_cursor_append(&callchain_cursor,
ip, al.map, al.sym);
if (err)
return err;
@@ -1428,7 +1429,6 @@ void perf_event__print_ip(union perf_event *event, struct perf_sample *sample,
int print_sym, int print_dso, int print_symoffset)
{
struct addr_location al;
- struct callchain_cursor *cursor = &evsel->hists.callchain_cursor;
struct callchain_cursor_node *node;
if (perf_event__preprocess_sample(event, machine, &al, sample,
@@ -1446,10 +1446,10 @@ void perf_event__print_ip(union perf_event *event, struct perf_sample *sample,
error("Failed to resolve callchain. Skipping\n");
return;
}
- callchain_cursor_commit(cursor);
+ callchain_cursor_commit(&callchain_cursor);
while (1) {
- node = callchain_cursor_current(cursor);
+ node = callchain_cursor_current(&callchain_cursor);
if (!node)
break;
@@ -1465,7 +1465,7 @@ void perf_event__print_ip(union perf_event *event, struct perf_sample *sample,
}
printf("\n");
- callchain_cursor_advance(cursor);
+ callchain_cursor_advance(&callchain_cursor);
}
} else {
--
1.7.10.2
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH/RFC 2/2] perf tools: Check callchain is corrupted
2012-05-31 5:43 [PATCH 1/2] perf callchain: Make callchain cursors TLS Namhyung Kim
@ 2012-05-31 5:43 ` Namhyung Kim
2012-05-31 13:45 ` Arnaldo Carvalho de Melo
` (2 more replies)
2012-06-01 17:50 ` [PATCH 1/2] perf callchain: Make callchain cursors TLS Zachary Landau
2012-06-06 7:00 ` [tip:perf/urgent] " tip-bot for Namhyung Kim
2 siblings, 3 replies; 9+ messages in thread
From: Namhyung Kim @ 2012-05-31 5:43 UTC (permalink / raw)
To: Arnaldo Carvalho de Melo
Cc: Peter Zijlstra, Paul Mackerras, Ingo Molnar, Namhyung Kim, LKML,
Sunjin Yang
We faced segmentation fault on perf top -G at very high sampling
rate due to a corrupted callchain. While the root cause was not
revealed (I failed to figure it out), this patch tries to protect
us from the segfault on such cases.
Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
---
include/linux/perf_event.h | 4 ++--
tools/perf/util/session.c | 14 +++++++++++++-
2 files changed, 15 insertions(+), 3 deletions(-)
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 8adf70e9e3cc..0430ea6054ef 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -555,6 +555,8 @@ enum perf_event_type {
PERF_RECORD_MAX, /* non-ABI */
};
+#define PERF_MAX_STACK_DEPTH 255
+
enum perf_callchain_context {
PERF_CONTEXT_HV = (__u64)-32,
PERF_CONTEXT_KERNEL = (__u64)-128,
@@ -609,8 +611,6 @@ struct perf_guest_info_callbacks {
#include <linux/sysfs.h>
#include <asm/local.h>
-#define PERF_MAX_STACK_DEPTH 255
-
struct perf_callchain_entry {
__u64 nr;
__u64 ip[PERF_MAX_STACK_DEPTH];
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index a7de2acac460..fa14e60ed459 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -300,6 +300,11 @@ int machine__resolve_callchain(struct machine *self,
callchain_cursor_reset(&callchain_cursor);
+ if (chain->nr > PERF_MAX_STACK_DEPTH) {
+ pr_warning("corrupted callchain. skipping...\n");
+ return 0;
+ }
+
for (i = 0; i < chain->nr; i++) {
u64 ip;
struct addr_location al;
@@ -318,7 +323,14 @@ int machine__resolve_callchain(struct machine *self,
case PERF_CONTEXT_USER:
cpumode = PERF_RECORD_MISC_USER; break;
default:
- break;
+ pr_debug("invalid callchain context: "
+ "%"PRId64"\n", (s64) ip);
+ /*
+ * It seems the callchain is corrupted.
+ * Discard all.
+ */
+ callchain_cursor_reset(&callchain_cursor);
+ return 0;
}
continue;
}
--
1.7.10.1
^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH/RFC 2/2] perf tools: Check callchain is corrupted
2012-05-31 5:43 ` [PATCH/RFC 2/2] perf tools: Check callchain is corrupted Namhyung Kim
@ 2012-05-31 13:45 ` Arnaldo Carvalho de Melo
2012-05-31 14:04 ` Namhyung Kim
2012-06-01 17:52 ` Zachary Landau
2012-06-06 7:01 ` [tip:perf/urgent] perf tools: Check if " tip-bot for Namhyung Kim
2 siblings, 1 reply; 9+ messages in thread
From: Arnaldo Carvalho de Melo @ 2012-05-31 13:45 UTC (permalink / raw)
To: Namhyung Kim
Cc: Peter Zijlstra, Paul Mackerras, Ingo Molnar, Namhyung Kim, LKML,
Sunjin Yang
Em Thu, May 31, 2012 at 02:43:27PM +0900, Namhyung Kim escreveu:
> We faced segmentation fault on perf top -G at very high sampling
> rate due to a corrupted callchain. While the root cause was not
> revealed (I failed to figure it out), this patch tries to protect
> us from the segfault on such cases.
Capping the callchain lenght may even be a feature, not a consistency
check, but I don't know how long, for consistency checking, we should
consider too much, as there are cases of loooong callchains.
Ingo? Peter?
- Arnaldo
> Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
> Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
> ---
> include/linux/perf_event.h | 4 ++--
> tools/perf/util/session.c | 14 +++++++++++++-
> 2 files changed, 15 insertions(+), 3 deletions(-)
>
> diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
> index 8adf70e9e3cc..0430ea6054ef 100644
> --- a/include/linux/perf_event.h
> +++ b/include/linux/perf_event.h
> @@ -555,6 +555,8 @@ enum perf_event_type {
> PERF_RECORD_MAX, /* non-ABI */
> };
>
> +#define PERF_MAX_STACK_DEPTH 255
> +
> enum perf_callchain_context {
> PERF_CONTEXT_HV = (__u64)-32,
> PERF_CONTEXT_KERNEL = (__u64)-128,
> @@ -609,8 +611,6 @@ struct perf_guest_info_callbacks {
> #include <linux/sysfs.h>
> #include <asm/local.h>
>
> -#define PERF_MAX_STACK_DEPTH 255
> -
> struct perf_callchain_entry {
> __u64 nr;
> __u64 ip[PERF_MAX_STACK_DEPTH];
> diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
> index a7de2acac460..fa14e60ed459 100644
> --- a/tools/perf/util/session.c
> +++ b/tools/perf/util/session.c
> @@ -300,6 +300,11 @@ int machine__resolve_callchain(struct machine *self,
>
> callchain_cursor_reset(&callchain_cursor);
>
> + if (chain->nr > PERF_MAX_STACK_DEPTH) {
> + pr_warning("corrupted callchain. skipping...\n");
> + return 0;
> + }
> +
> for (i = 0; i < chain->nr; i++) {
> u64 ip;
> struct addr_location al;
> @@ -318,7 +323,14 @@ int machine__resolve_callchain(struct machine *self,
> case PERF_CONTEXT_USER:
> cpumode = PERF_RECORD_MISC_USER; break;
> default:
> - break;
> + pr_debug("invalid callchain context: "
> + "%"PRId64"\n", (s64) ip);
> + /*
> + * It seems the callchain is corrupted.
> + * Discard all.
> + */
> + callchain_cursor_reset(&callchain_cursor);
> + return 0;
> }
> continue;
> }
> --
> 1.7.10.1
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH/RFC 2/2] perf tools: Check callchain is corrupted
2012-05-31 13:45 ` Arnaldo Carvalho de Melo
@ 2012-05-31 14:04 ` Namhyung Kim
2012-05-31 14:31 ` Arnaldo Carvalho de Melo
0 siblings, 1 reply; 9+ messages in thread
From: Namhyung Kim @ 2012-05-31 14:04 UTC (permalink / raw)
To: Arnaldo Carvalho de Melo
Cc: Namhyung Kim, Peter Zijlstra, Paul Mackerras, Ingo Molnar, LKML,
Sunjin Yang, Arun Sharma
Hi,
2012-05-31 (목), 10:45 -0300, Arnaldo Carvalho de Melo:
> Em Thu, May 31, 2012 at 02:43:27PM +0900, Namhyung Kim escreveu:
> > We faced segmentation fault on perf top -G at very high sampling
> > rate due to a corrupted callchain. While the root cause was not
> > revealed (I failed to figure it out), this patch tries to protect
> > us from the segfault on such cases.
>
> Capping the callchain lenght may even be a feature, not a consistency
> check, but I don't know how long, for consistency checking, we should
> consider too much, as there are cases of loooong callchains.
>
Maybe we should consider applying (a part of, at least) Arun's multiple
stack patchset. Also note that Linus complained about the current stack
depth (255) is too long.
https://lkml.org/lkml/2012/4/20/497
--
Regards,
Namhyung Kim
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH/RFC 2/2] perf tools: Check callchain is corrupted
2012-05-31 14:04 ` Namhyung Kim
@ 2012-05-31 14:31 ` Arnaldo Carvalho de Melo
0 siblings, 0 replies; 9+ messages in thread
From: Arnaldo Carvalho de Melo @ 2012-05-31 14:31 UTC (permalink / raw)
To: Namhyung Kim
Cc: Namhyung Kim, Peter Zijlstra, Paul Mackerras, Ingo Molnar, LKML,
Sunjin Yang, Arun Sharma
Em Thu, May 31, 2012 at 11:04:37PM +0900, Namhyung Kim escreveu:
> 2012-05-31 (목), 10:45 -0300, Arnaldo Carvalho de Melo:
> > Em Thu, May 31, 2012 at 02:43:27PM +0900, Namhyung Kim escreveu:
> > > We faced segmentation fault on perf top -G at very high sampling
> > > rate due to a corrupted callchain. While the root cause was not
> > > revealed (I failed to figure it out), this patch tries to protect
> > > us from the segfault on such cases.
> > Capping the callchain lenght may even be a feature, not a consistency
> > check, but I don't know how long, for consistency checking, we should
> > consider too much, as there are cases of loooong callchains.
> Maybe we should consider applying (a part of, at least) Arun's multiple
> stack patchset. Also note that Linus complained about the current stack
> depth (255) is too long.
> https://lkml.org/lkml/2012/4/20/497
Ok, I applied it, 'perf top -G -F 100000' now is holding up, no
segfaults, yay!
Thanks,
- Arnaldo
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH 1/2] perf callchain: Make callchain cursors TLS
2012-05-31 5:43 [PATCH 1/2] perf callchain: Make callchain cursors TLS Namhyung Kim
2012-05-31 5:43 ` [PATCH/RFC 2/2] perf tools: Check callchain is corrupted Namhyung Kim
@ 2012-06-01 17:50 ` Zachary Landau
2012-06-06 7:00 ` [tip:perf/urgent] " tip-bot for Namhyung Kim
2 siblings, 0 replies; 9+ messages in thread
From: Zachary Landau @ 2012-06-01 17:50 UTC (permalink / raw)
To: Namhyung Kim
Cc: Arnaldo Carvalho de Melo, Peter Zijlstra, Paul Mackerras,
Ingo Molnar, Namhyung Kim, LKML, Sunjin Yang
On Thu, May 31, 2012 at 02:43:26PM +0900, Namhyung Kim wrote:
> perf top -G has a race on callchain cursor between main
> thread and display thread. Since the callchain cursors
> are used locally make them thread-local data would solve
> the problem.
>
> Reported-by: Sunjin Yang <fan4326@gmail.com>
> Suggested-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
> Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
Acked-by: Zachary Landau <zacharyl@fb.com>
- Zack
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH/RFC 2/2] perf tools: Check callchain is corrupted
2012-05-31 5:43 ` [PATCH/RFC 2/2] perf tools: Check callchain is corrupted Namhyung Kim
2012-05-31 13:45 ` Arnaldo Carvalho de Melo
@ 2012-06-01 17:52 ` Zachary Landau
2012-06-06 7:01 ` [tip:perf/urgent] perf tools: Check if " tip-bot for Namhyung Kim
2 siblings, 0 replies; 9+ messages in thread
From: Zachary Landau @ 2012-06-01 17:52 UTC (permalink / raw)
To: Namhyung Kim
Cc: Arnaldo Carvalho de Melo, Peter Zijlstra, Paul Mackerras,
Ingo Molnar, Namhyung Kim, LKML, Sunjin Yang
On Thu, May 31, 2012 at 02:43:27PM +0900, Namhyung Kim wrote:
> We faced segmentation fault on perf top -G at very high sampling
> rate due to a corrupted callchain. While the root cause was not
> revealed (I failed to figure it out), this patch tries to protect
> us from the segfault on such cases.
>
> Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
> Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
Acked-by: Zachary Landau <zacharyl@fb.com>
- Zack
^ permalink raw reply [flat|nested] 9+ messages in thread
* [tip:perf/urgent] perf callchain: Make callchain cursors TLS
2012-05-31 5:43 [PATCH 1/2] perf callchain: Make callchain cursors TLS Namhyung Kim
2012-05-31 5:43 ` [PATCH/RFC 2/2] perf tools: Check callchain is corrupted Namhyung Kim
2012-06-01 17:50 ` [PATCH 1/2] perf callchain: Make callchain cursors TLS Zachary Landau
@ 2012-06-06 7:00 ` tip-bot for Namhyung Kim
2 siblings, 0 replies; 9+ messages in thread
From: tip-bot for Namhyung Kim @ 2012-06-06 7:00 UTC (permalink / raw)
To: linux-tip-commits
Cc: acme, linux-kernel, paulus, mingo, hpa, mingo, a.p.zijlstra, acme,
namhyung.kim, namhyung, fan4326, tglx
Commit-ID: 472606458f3e1ced5fe3cc5f04e90a6b5a4732cf
Gitweb: http://git.kernel.org/tip/472606458f3e1ced5fe3cc5f04e90a6b5a4732cf
Author: Namhyung Kim <namhyung.kim@lge.com>
AuthorDate: Thu, 31 May 2012 14:43:26 +0900
Committer: Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Thu, 31 May 2012 10:47:12 -0300
perf callchain: Make callchain cursors TLS
perf top -G has a race on callchain cursor between main thread and
display thread. Since the callchain cursors are used locally make them
thread-local data would solve the problem.
Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
Reported-by: Sunjin Yang <fan4326@gmail.com>
Suggested-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Sunjin Yang <fan4326@gmail.com>
Link: http://lkml.kernel.org/r/1338443007-24857-1-git-send-email-namhyung.kim@lge.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/builtin-report.c | 2 +-
tools/perf/builtin-top.c | 2 +-
tools/perf/util/callchain.c | 2 ++
tools/perf/util/callchain.h | 2 ++
tools/perf/util/hist.c | 7 ++++---
tools/perf/util/hist.h | 2 --
tools/perf/util/session.c | 14 +++++++-------
7 files changed, 17 insertions(+), 14 deletions(-)
diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 2400e00..25249f7 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -152,7 +152,7 @@ static int perf_evsel__add_hist_entry(struct perf_evsel *evsel,
if (symbol_conf.use_callchain) {
err = callchain_append(he->callchain,
- &evsel->hists.callchain_cursor,
+ &callchain_cursor,
sample->period);
if (err)
return err;
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 871b540..6bb0277 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -787,7 +787,7 @@ static void perf_event__process_sample(struct perf_tool *tool,
}
if (symbol_conf.use_callchain) {
- err = callchain_append(he->callchain, &evsel->hists.callchain_cursor,
+ err = callchain_append(he->callchain, &callchain_cursor,
sample->period);
if (err)
return;
diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c
index 9f7106a..3a6bff4 100644
--- a/tools/perf/util/callchain.c
+++ b/tools/perf/util/callchain.c
@@ -18,6 +18,8 @@
#include "util.h"
#include "callchain.h"
+__thread struct callchain_cursor callchain_cursor;
+
bool ip_callchain__valid(struct ip_callchain *chain,
const union perf_event *event)
{
diff --git a/tools/perf/util/callchain.h b/tools/perf/util/callchain.h
index 7f9c0f1..3bdb407 100644
--- a/tools/perf/util/callchain.h
+++ b/tools/perf/util/callchain.h
@@ -76,6 +76,8 @@ struct callchain_cursor {
struct callchain_cursor_node *curr;
};
+extern __thread struct callchain_cursor callchain_cursor;
+
static inline void callchain_init(struct callchain_root *root)
{
INIT_LIST_HEAD(&root->node.siblings);
diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
index 1293b5e..514e2a4 100644
--- a/tools/perf/util/hist.c
+++ b/tools/perf/util/hist.c
@@ -378,7 +378,7 @@ void hist_entry__free(struct hist_entry *he)
* collapse the histogram
*/
-static bool hists__collapse_insert_entry(struct hists *hists,
+static bool hists__collapse_insert_entry(struct hists *hists __used,
struct rb_root *root,
struct hist_entry *he)
{
@@ -397,8 +397,9 @@ static bool hists__collapse_insert_entry(struct hists *hists,
iter->period += he->period;
iter->nr_events += he->nr_events;
if (symbol_conf.use_callchain) {
- callchain_cursor_reset(&hists->callchain_cursor);
- callchain_merge(&hists->callchain_cursor, iter->callchain,
+ callchain_cursor_reset(&callchain_cursor);
+ callchain_merge(&callchain_cursor,
+ iter->callchain,
he->callchain);
}
hist_entry__free(he);
diff --git a/tools/perf/util/hist.h b/tools/perf/util/hist.h
index cfc64e2..34bb556 100644
--- a/tools/perf/util/hist.h
+++ b/tools/perf/util/hist.h
@@ -67,8 +67,6 @@ struct hists {
struct events_stats stats;
u64 event_stream;
u16 col_len[HISTC_NR_COLS];
- /* Best would be to reuse the session callchain cursor */
- struct callchain_cursor callchain_cursor;
};
struct hist_entry *__hists__add_entry(struct hists *self,
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 4820614..3b6f8e4 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -288,7 +288,8 @@ struct branch_info *machine__resolve_bstack(struct machine *self,
return bi;
}
-int machine__resolve_callchain(struct machine *self, struct perf_evsel *evsel,
+int machine__resolve_callchain(struct machine *self,
+ struct perf_evsel *evsel __used,
struct thread *thread,
struct ip_callchain *chain,
struct symbol **parent)
@@ -297,7 +298,7 @@ int machine__resolve_callchain(struct machine *self, struct perf_evsel *evsel,
unsigned int i;
int err;
- callchain_cursor_reset(&evsel->hists.callchain_cursor);
+ callchain_cursor_reset(&callchain_cursor);
for (i = 0; i < chain->nr; i++) {
u64 ip;
@@ -333,7 +334,7 @@ int machine__resolve_callchain(struct machine *self, struct perf_evsel *evsel,
break;
}
- err = callchain_cursor_append(&evsel->hists.callchain_cursor,
+ err = callchain_cursor_append(&callchain_cursor,
ip, al.map, al.sym);
if (err)
return err;
@@ -1428,7 +1429,6 @@ void perf_event__print_ip(union perf_event *event, struct perf_sample *sample,
int print_sym, int print_dso, int print_symoffset)
{
struct addr_location al;
- struct callchain_cursor *cursor = &evsel->hists.callchain_cursor;
struct callchain_cursor_node *node;
if (perf_event__preprocess_sample(event, machine, &al, sample,
@@ -1446,10 +1446,10 @@ void perf_event__print_ip(union perf_event *event, struct perf_sample *sample,
error("Failed to resolve callchain. Skipping\n");
return;
}
- callchain_cursor_commit(cursor);
+ callchain_cursor_commit(&callchain_cursor);
while (1) {
- node = callchain_cursor_current(cursor);
+ node = callchain_cursor_current(&callchain_cursor);
if (!node)
break;
@@ -1465,7 +1465,7 @@ void perf_event__print_ip(union perf_event *event, struct perf_sample *sample,
}
printf("\n");
- callchain_cursor_advance(cursor);
+ callchain_cursor_advance(&callchain_cursor);
}
} else {
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [tip:perf/urgent] perf tools: Check if callchain is corrupted
2012-05-31 5:43 ` [PATCH/RFC 2/2] perf tools: Check callchain is corrupted Namhyung Kim
2012-05-31 13:45 ` Arnaldo Carvalho de Melo
2012-06-01 17:52 ` Zachary Landau
@ 2012-06-06 7:01 ` tip-bot for Namhyung Kim
2 siblings, 0 replies; 9+ messages in thread
From: tip-bot for Namhyung Kim @ 2012-06-06 7:01 UTC (permalink / raw)
To: linux-tip-commits
Cc: linux-kernel, paulus, acme, hpa, mingo, a.p.zijlstra,
namhyung.kim, namhyung, fan4326, tglx
Commit-ID: 114067b69e7b2c691faace0e33db2f04096f668d
Gitweb: http://git.kernel.org/tip/114067b69e7b2c691faace0e33db2f04096f668d
Author: Namhyung Kim <namhyung.kim@lge.com>
AuthorDate: Thu, 31 May 2012 14:43:27 +0900
Committer: Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Thu, 31 May 2012 11:20:34 -0300
perf tools: Check if callchain is corrupted
We faced segmentation fault on perf top -G at very high sampling rate
due to a corrupted callchain. While the root cause was not revealed (I
failed to figure it out), this patch tries to protect us from the
segfault on such cases.
Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Sunjin Yang <fan4326@gmail.com>
Link: http://lkml.kernel.org/r/1338443007-24857-2-git-send-email-namhyung.kim@lge.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
include/linux/perf_event.h | 4 ++--
tools/perf/util/session.c | 14 +++++++++++++-
2 files changed, 15 insertions(+), 3 deletions(-)
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index f325786..1817d40 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -555,6 +555,8 @@ enum perf_event_type {
PERF_RECORD_MAX, /* non-ABI */
};
+#define PERF_MAX_STACK_DEPTH 255
+
enum perf_callchain_context {
PERF_CONTEXT_HV = (__u64)-32,
PERF_CONTEXT_KERNEL = (__u64)-128,
@@ -609,8 +611,6 @@ struct perf_guest_info_callbacks {
#include <linux/sysfs.h>
#include <asm/local.h>
-#define PERF_MAX_STACK_DEPTH 255
-
struct perf_callchain_entry {
__u64 nr;
__u64 ip[PERF_MAX_STACK_DEPTH];
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 3b6f8e4..04d1e33 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -300,6 +300,11 @@ int machine__resolve_callchain(struct machine *self,
callchain_cursor_reset(&callchain_cursor);
+ if (chain->nr > PERF_MAX_STACK_DEPTH) {
+ pr_warning("corrupted callchain. skipping...\n");
+ return 0;
+ }
+
for (i = 0; i < chain->nr; i++) {
u64 ip;
struct addr_location al;
@@ -318,7 +323,14 @@ int machine__resolve_callchain(struct machine *self,
case PERF_CONTEXT_USER:
cpumode = PERF_RECORD_MISC_USER; break;
default:
- break;
+ pr_debug("invalid callchain context: "
+ "%"PRId64"\n", (s64) ip);
+ /*
+ * It seems the callchain is corrupted.
+ * Discard all.
+ */
+ callchain_cursor_reset(&callchain_cursor);
+ return 0;
}
continue;
}
^ permalink raw reply related [flat|nested] 9+ messages in thread
end of thread, other threads:[~2012-06-06 7:02 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2012-05-31 5:43 [PATCH 1/2] perf callchain: Make callchain cursors TLS Namhyung Kim
2012-05-31 5:43 ` [PATCH/RFC 2/2] perf tools: Check callchain is corrupted Namhyung Kim
2012-05-31 13:45 ` Arnaldo Carvalho de Melo
2012-05-31 14:04 ` Namhyung Kim
2012-05-31 14:31 ` Arnaldo Carvalho de Melo
2012-06-01 17:52 ` Zachary Landau
2012-06-06 7:01 ` [tip:perf/urgent] perf tools: Check if " tip-bot for Namhyung Kim
2012-06-01 17:50 ` [PATCH 1/2] perf callchain: Make callchain cursors TLS Zachary Landau
2012-06-06 7:00 ` [tip:perf/urgent] " tip-bot for Namhyung Kim
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