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* PEBS (in perf) stopped working from 3.6 -> 3.7
@ 2013-01-04 23:47 Steinar H. Gunderson
  2013-01-05  0:16 ` David Ahern
  0 siblings, 1 reply; 6+ messages in thread
From: Steinar H. Gunderson @ 2013-01-04 23:47 UTC (permalink / raw)
  To: linux-kernel

[Please Cc me on any replies; I'm not subscribed to lkml]

Hi,

I recently upgraded from 3.6.5 to 3.7.1 to get around some MM issues that
have been bothering me. However, it appears it broke PEBS:

  pannekake:/usr/src/linux-3.7.1# perf record -a -e cycles:pp

  Error: sys_perf_event_open() syscall returned with 95 (Operation not supported).  /bin/dmesg may provide additional information.

  Fatal: No hardware sampling interrupt available. No APIC? If so then you can boot the kernel with the "lapic" boot parameter to force-enable it.

Non-precise tracing works fine. This used to work in 3.6.5, and I used make
oldconfig (not that I can find any .config settings that would seem relevant
either). I certainly have APIC. There's nothing in dmesg about the error.
I'm using perf built from the same kernel tree (ie., 3.7.1).

This is on a dual Xeon E5520 (ie. Westmere), on a Supermicro board.

/* Steinar */
-- 
Chief, Tech:Server
http://www.sesse.net/

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: PEBS (in perf) stopped working from 3.6 -> 3.7
  2013-01-04 23:47 PEBS (in perf) stopped working from 3.6 -> 3.7 Steinar H. Gunderson
@ 2013-01-05  0:16 ` David Ahern
  2013-01-05  0:21   ` Steinar H. Gunderson
  2013-01-05  1:05   ` Steinar H. Gunderson
  0 siblings, 2 replies; 6+ messages in thread
From: David Ahern @ 2013-01-05  0:16 UTC (permalink / raw)
  To: Steinar H. Gunderson; +Cc: linux-kernel

On 1/4/13 4:47 PM, Steinar H. Gunderson wrote:
> [Please Cc me on any replies; I'm not subscribed to lkml]
>
> Hi,
>
> I recently upgraded from 3.6.5 to 3.7.1 to get around some MM issues that
> have been bothering me. However, it appears it broke PEBS:
>
>    pannekake:/usr/src/linux-3.7.1# perf record -a -e cycles:pp
>
>    Error: sys_perf_event_open() syscall returned with 95 (Operation not supported).  /bin/dmesg may provide additional information.
>
>    Fatal: No hardware sampling interrupt available. No APIC? If so then you can boot the kernel with the "lapic" boot parameter to force-enable it.

Known problem. Pick one of: update perf to 3.7, add H to the command (-e 
cycles:ppH) or apply this patch: https://lkml.org/lkml/2012/12/28/384

David

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: PEBS (in perf) stopped working from 3.6 -> 3.7
  2013-01-05  0:16 ` David Ahern
@ 2013-01-05  0:21   ` Steinar H. Gunderson
  2013-01-05  1:05   ` Steinar H. Gunderson
  1 sibling, 0 replies; 6+ messages in thread
From: Steinar H. Gunderson @ 2013-01-05  0:21 UTC (permalink / raw)
  To: David Ahern; +Cc: linux-kernel

On Fri, Jan 04, 2013 at 05:16:27PM -0700, David Ahern wrote:
> Known problem. Pick one of: update perf to 3.7, add H to the command
> (-e cycles:ppH) or apply this patch:
> https://lkml.org/lkml/2012/12/28/384

Oh, thinking of it, I've actually read about this flamew^Wdiscussion :-)

Thanks!

/* Steinar */
-- 
Homepage: http://www.sesse.net/

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: PEBS (in perf) stopped working from 3.6 -> 3.7
  2013-01-05  0:16 ` David Ahern
  2013-01-05  0:21   ` Steinar H. Gunderson
@ 2013-01-05  1:05   ` Steinar H. Gunderson
  2013-01-07  3:48     ` David Ahern
  1 sibling, 1 reply; 6+ messages in thread
From: Steinar H. Gunderson @ 2013-01-05  1:05 UTC (permalink / raw)
  To: David Ahern; +Cc: linux-kernel

On Fri, Jan 04, 2013 at 05:16:27PM -0700, David Ahern wrote:
> Known problem. Pick one of: update perf to 3.7, add H to the command
> (-e cycles:ppH) or apply this patch:
> https://lkml.org/lkml/2012/12/28/384

I spoke too soon. This works for cycles, but not for branch-misses:

  pannekake:~> sudo perf record -e branch-misses:ppH -a
  
    Error: sys_perf_event_open() syscall returned with 95 (Operation not supported) for event branch-misses:ppH. /bin/dmesg may provide additional information.
  
  No hardware sampling interrupt available. No APIC? If so then you can boot the kernel with the "lapic" boot parameter to force-enable it.

Why would the two be different?

/* Steinar */
-- 
Homepage: http://www.sesse.net/

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: PEBS (in perf) stopped working from 3.6 -> 3.7
  2013-01-05  1:05   ` Steinar H. Gunderson
@ 2013-01-07  3:48     ` David Ahern
  2013-01-07 14:40       ` Steinar H. Gunderson
  0 siblings, 1 reply; 6+ messages in thread
From: David Ahern @ 2013-01-07  3:48 UTC (permalink / raw)
  To: Steinar H. Gunderson; +Cc: linux-kernel

On 1/4/13 6:05 PM, Steinar H. Gunderson wrote:
> On Fri, Jan 04, 2013 at 05:16:27PM -0700, David Ahern wrote:
>> Known problem. Pick one of: update perf to 3.7, add H to the command
>> (-e cycles:ppH) or apply this patch:
>> https://lkml.org/lkml/2012/12/28/384
>
> I spoke too soon. This works for cycles, but not for branch-misses:
>
>    pannekake:~> sudo perf record -e branch-misses:ppH -a
>
>      Error: sys_perf_event_open() syscall returned with 95 (Operation not supported) for event branch-misses:ppH. /bin/dmesg may provide additional information.
>
>    No hardware sampling interrupt available. No APIC? If so then you can boot the kernel with the "lapic" boot parameter to force-enable it.
>
> Why would the two be different?

I will make a guess that is processor dependent. On an E5540 with 
3.4.11-1.fc16.x86_64, 3.6.10-2.fc16.x86_64, and 3.8 I get the same 
failure message.

But on a E5620, it works fine with 3.4 and 3.7 (no intermediate kernels 
on that box).

David

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: PEBS (in perf) stopped working from 3.6 -> 3.7
  2013-01-07  3:48     ` David Ahern
@ 2013-01-07 14:40       ` Steinar H. Gunderson
  0 siblings, 0 replies; 6+ messages in thread
From: Steinar H. Gunderson @ 2013-01-07 14:40 UTC (permalink / raw)
  To: David Ahern; +Cc: linux-kernel

On Sun, Jan 06, 2013 at 08:48:36PM -0700, David Ahern wrote:
>> Why would the two be different?
> I will make a guess that is processor dependent. On an E5540 with
> 3.4.11-1.fc16.x86_64, 3.6.10-2.fc16.x86_64, and 3.8 I get the same
> failure message.
> 
> But on a E5620, it works fine with 3.4 and 3.7 (no intermediate
> kernels on that box).

That sounds a bit odd; the CPU can certainly do it with 3.6.

/* Steinar */
-- 
Homepage: http://www.sesse.net/

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2013-01-07 14:40 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-01-04 23:47 PEBS (in perf) stopped working from 3.6 -> 3.7 Steinar H. Gunderson
2013-01-05  0:16 ` David Ahern
2013-01-05  0:21   ` Steinar H. Gunderson
2013-01-05  1:05   ` Steinar H. Gunderson
2013-01-07  3:48     ` David Ahern
2013-01-07 14:40       ` Steinar H. Gunderson

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