Re: PEBS (in perf) stopped working from 3.6 -> 3.7

From: Steinar H. Gunderson
Date: Fri Jan 04 2013 - 20:05:03 EST


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 */
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