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* [PATCH] perf tools: Fix trigger class trigger_on()
@ 2018-02-28  8:39 Adrian Hunter
  2018-02-28  9:23 ` Jiri Olsa
  2018-03-07  8:28 ` [tip:perf/urgent] " tip-bot for Adrian Hunter
  0 siblings, 2 replies; 3+ messages in thread
From: Adrian Hunter @ 2018-02-28  8:39 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo; +Cc: Jiri Olsa, Wang Nan, linux-kernel

trigger_on() means that the trigger is available but not ready, however
trigger_on() was making it ready. That can segfault if the signal comes
before trigger_ready(). e.g. (USR2 signal delivery not shown)

  $ perf record -e intel_pt//u -S sleep 1
  perf: Segmentation fault
  Obtained 16 stack frames.
  /home/ahunter/bin/perf(sighandler_dump_stack+0x40) [0x4ec550]
  /lib/x86_64-linux-gnu/libc.so.6(+0x36caf) [0x7fa76411acaf]
  /home/ahunter/bin/perf(perf_evsel__disable+0x26) [0x4b9dd6]
  /home/ahunter/bin/perf() [0x43a45b]
  /lib/x86_64-linux-gnu/libc.so.6(+0x36caf) [0x7fa76411acaf]
  /lib/x86_64-linux-gnu/libc.so.6(__xstat64+0x15) [0x7fa7641d2cc5]
  /home/ahunter/bin/perf() [0x4ec6c9]
  /home/ahunter/bin/perf() [0x4ec73b]
  /home/ahunter/bin/perf() [0x4ec73b]
  /home/ahunter/bin/perf() [0x4ec73b]
  /home/ahunter/bin/perf() [0x4eca15]
  /home/ahunter/bin/perf(machine__create_kernel_maps+0x257) [0x4f0b77]
  /home/ahunter/bin/perf(perf_session__new+0xc0) [0x4f86f0]
  /home/ahunter/bin/perf(cmd_record+0x722) [0x43c132]
  /home/ahunter/bin/perf() [0x4a11ae]
  /home/ahunter/bin/perf(main+0x5d4) [0x427fb4]

Note, for testing purposes, this is hard to hit unless you add some sleep()
in builtin-record.c before record__open().

Fixes: 3dcc4436fa6f ("perf tools: Introduce trigger class")
Cc: <stable@vger.kernel.org>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
 tools/perf/util/trigger.h | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/tools/perf/util/trigger.h b/tools/perf/util/trigger.h
index 370138e7e35c..88223bc7c82b 100644
--- a/tools/perf/util/trigger.h
+++ b/tools/perf/util/trigger.h
@@ -12,7 +12,7 @@
  * States and transits:
  *
  *
- *  OFF--(on)--> READY --(hit)--> HIT
+ *  OFF--> ON --> READY --(hit)--> HIT
  *                 ^               |
  *                 |            (ready)
  *                 |               |
@@ -27,8 +27,9 @@ struct trigger {
 	volatile enum {
 		TRIGGER_ERROR		= -2,
 		TRIGGER_OFF		= -1,
-		TRIGGER_READY		= 0,
-		TRIGGER_HIT		= 1,
+		TRIGGER_ON		= 0,
+		TRIGGER_READY		= 1,
+		TRIGGER_HIT		= 2,
 	} state;
 	const char *name;
 };
@@ -50,7 +51,7 @@ static inline bool trigger_is_error(struct trigger *t)
 static inline void trigger_on(struct trigger *t)
 {
 	TRIGGER_WARN_ONCE(t, TRIGGER_OFF);
-	t->state = TRIGGER_READY;
+	t->state = TRIGGER_ON;
 }
 
 static inline void trigger_ready(struct trigger *t)
-- 
1.9.1

^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH] perf tools: Fix trigger class trigger_on()
  2018-02-28  8:39 [PATCH] perf tools: Fix trigger class trigger_on() Adrian Hunter
@ 2018-02-28  9:23 ` Jiri Olsa
  2018-03-07  8:28 ` [tip:perf/urgent] " tip-bot for Adrian Hunter
  1 sibling, 0 replies; 3+ messages in thread
From: Jiri Olsa @ 2018-02-28  9:23 UTC (permalink / raw)
  To: Adrian Hunter; +Cc: Arnaldo Carvalho de Melo, Wang Nan, linux-kernel

On Wed, Feb 28, 2018 at 10:39:04AM +0200, Adrian Hunter wrote:
> trigger_on() means that the trigger is available but not ready, however
> trigger_on() was making it ready. That can segfault if the signal comes
> before trigger_ready(). e.g. (USR2 signal delivery not shown)
> 
>   $ perf record -e intel_pt//u -S sleep 1
>   perf: Segmentation fault
>   Obtained 16 stack frames.
>   /home/ahunter/bin/perf(sighandler_dump_stack+0x40) [0x4ec550]
>   /lib/x86_64-linux-gnu/libc.so.6(+0x36caf) [0x7fa76411acaf]
>   /home/ahunter/bin/perf(perf_evsel__disable+0x26) [0x4b9dd6]
>   /home/ahunter/bin/perf() [0x43a45b]
>   /lib/x86_64-linux-gnu/libc.so.6(+0x36caf) [0x7fa76411acaf]
>   /lib/x86_64-linux-gnu/libc.so.6(__xstat64+0x15) [0x7fa7641d2cc5]
>   /home/ahunter/bin/perf() [0x4ec6c9]
>   /home/ahunter/bin/perf() [0x4ec73b]
>   /home/ahunter/bin/perf() [0x4ec73b]
>   /home/ahunter/bin/perf() [0x4ec73b]
>   /home/ahunter/bin/perf() [0x4eca15]
>   /home/ahunter/bin/perf(machine__create_kernel_maps+0x257) [0x4f0b77]
>   /home/ahunter/bin/perf(perf_session__new+0xc0) [0x4f86f0]
>   /home/ahunter/bin/perf(cmd_record+0x722) [0x43c132]
>   /home/ahunter/bin/perf() [0x4a11ae]
>   /home/ahunter/bin/perf(main+0x5d4) [0x427fb4]
> 
> Note, for testing purposes, this is hard to hit unless you add some sleep()
> in builtin-record.c before record__open().
> 
> Fixes: 3dcc4436fa6f ("perf tools: Introduce trigger class")
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>

Acked-by: Jiri Olsa <jolsa@kernel.org>

thanks,
jirka

> ---
>  tools/perf/util/trigger.h | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/tools/perf/util/trigger.h b/tools/perf/util/trigger.h
> index 370138e7e35c..88223bc7c82b 100644
> --- a/tools/perf/util/trigger.h
> +++ b/tools/perf/util/trigger.h
> @@ -12,7 +12,7 @@
>   * States and transits:
>   *
>   *
> - *  OFF--(on)--> READY --(hit)--> HIT
> + *  OFF--> ON --> READY --(hit)--> HIT
>   *                 ^               |
>   *                 |            (ready)
>   *                 |               |
> @@ -27,8 +27,9 @@ struct trigger {
>  	volatile enum {
>  		TRIGGER_ERROR		= -2,
>  		TRIGGER_OFF		= -1,
> -		TRIGGER_READY		= 0,
> -		TRIGGER_HIT		= 1,
> +		TRIGGER_ON		= 0,
> +		TRIGGER_READY		= 1,
> +		TRIGGER_HIT		= 2,
>  	} state;
>  	const char *name;
>  };
> @@ -50,7 +51,7 @@ static inline bool trigger_is_error(struct trigger *t)
>  static inline void trigger_on(struct trigger *t)
>  {
>  	TRIGGER_WARN_ONCE(t, TRIGGER_OFF);
> -	t->state = TRIGGER_READY;
> +	t->state = TRIGGER_ON;
>  }
>  
>  static inline void trigger_ready(struct trigger *t)
> -- 
> 1.9.1
> 

^ permalink raw reply	[flat|nested] 3+ messages in thread

* [tip:perf/urgent] perf tools: Fix trigger class trigger_on()
  2018-02-28  8:39 [PATCH] perf tools: Fix trigger class trigger_on() Adrian Hunter
  2018-02-28  9:23 ` Jiri Olsa
@ 2018-03-07  8:28 ` tip-bot for Adrian Hunter
  1 sibling, 0 replies; 3+ messages in thread
From: tip-bot for Adrian Hunter @ 2018-03-07  8:28 UTC (permalink / raw)
  To: linux-tip-commits
  Cc: tglx, acme, wangnan0, mingo, adrian.hunter, hpa, jolsa,
	linux-kernel

Commit-ID:  de19e5c3c51fdb1ff20d0f61d099db902ff7494b
Gitweb:     https://git.kernel.org/tip/de19e5c3c51fdb1ff20d0f61d099db902ff7494b
Author:     Adrian Hunter <adrian.hunter@intel.com>
AuthorDate: Wed, 28 Feb 2018 10:39:04 +0200
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Tue, 6 Mar 2018 11:31:14 -0300

perf tools: Fix trigger class trigger_on()

trigger_on() means that the trigger is available but not ready, however
trigger_on() was making it ready. That can segfault if the signal comes
before trigger_ready(). e.g. (USR2 signal delivery not shown)

  $ perf record -e intel_pt//u -S sleep 1
  perf: Segmentation fault
  Obtained 16 stack frames.
  /home/ahunter/bin/perf(sighandler_dump_stack+0x40) [0x4ec550]
  /lib/x86_64-linux-gnu/libc.so.6(+0x36caf) [0x7fa76411acaf]
  /home/ahunter/bin/perf(perf_evsel__disable+0x26) [0x4b9dd6]
  /home/ahunter/bin/perf() [0x43a45b]
  /lib/x86_64-linux-gnu/libc.so.6(+0x36caf) [0x7fa76411acaf]
  /lib/x86_64-linux-gnu/libc.so.6(__xstat64+0x15) [0x7fa7641d2cc5]
  /home/ahunter/bin/perf() [0x4ec6c9]
  /home/ahunter/bin/perf() [0x4ec73b]
  /home/ahunter/bin/perf() [0x4ec73b]
  /home/ahunter/bin/perf() [0x4ec73b]
  /home/ahunter/bin/perf() [0x4eca15]
  /home/ahunter/bin/perf(machine__create_kernel_maps+0x257) [0x4f0b77]
  /home/ahunter/bin/perf(perf_session__new+0xc0) [0x4f86f0]
  /home/ahunter/bin/perf(cmd_record+0x722) [0x43c132]
  /home/ahunter/bin/perf() [0x4a11ae]
  /home/ahunter/bin/perf(main+0x5d4) [0x427fb4]

Note, for testing purposes, this is hard to hit unless you add some sleep()
in builtin-record.c before record__open().

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: stable@vger.kernel.org
Fixes: 3dcc4436fa6f ("perf tools: Introduce trigger class")
Link: http://lkml.kernel.org/r/1519807144-30694-1-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/trigger.h | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/tools/perf/util/trigger.h b/tools/perf/util/trigger.h
index 370138e7e35c..88223bc7c82b 100644
--- a/tools/perf/util/trigger.h
+++ b/tools/perf/util/trigger.h
@@ -12,7 +12,7 @@
  * States and transits:
  *
  *
- *  OFF--(on)--> READY --(hit)--> HIT
+ *  OFF--> ON --> READY --(hit)--> HIT
  *                 ^               |
  *                 |            (ready)
  *                 |               |
@@ -27,8 +27,9 @@ struct trigger {
 	volatile enum {
 		TRIGGER_ERROR		= -2,
 		TRIGGER_OFF		= -1,
-		TRIGGER_READY		= 0,
-		TRIGGER_HIT		= 1,
+		TRIGGER_ON		= 0,
+		TRIGGER_READY		= 1,
+		TRIGGER_HIT		= 2,
 	} state;
 	const char *name;
 };
@@ -50,7 +51,7 @@ static inline bool trigger_is_error(struct trigger *t)
 static inline void trigger_on(struct trigger *t)
 {
 	TRIGGER_WARN_ONCE(t, TRIGGER_OFF);
-	t->state = TRIGGER_READY;
+	t->state = TRIGGER_ON;
 }
 
 static inline void trigger_ready(struct trigger *t)

^ permalink raw reply related	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2018-03-07  8:28 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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2018-02-28  8:39 [PATCH] perf tools: Fix trigger class trigger_on() Adrian Hunter
2018-02-28  9:23 ` Jiri Olsa
2018-03-07  8:28 ` [tip:perf/urgent] " tip-bot for Adrian Hunter

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