Re: [PATCH 3/4] perf tools: Fix probing the kernel API with cpu-wide events

From: Adrian Hunter
Date: Wed Aug 13 2014 - 01:53:23 EST

On 08/13/2014 08:37 AM, Namhyung Kim wrote:
> On Tue, 12 Aug 2014 18:04:30 +0300, Adrian Hunter wrote:
>> Fall back to probing with the current pid if cpu-wide
>> probing fails. This primarily affects the setting of
>> comm_exec flag when the user is un-privileged and
>> /proc/sys/kernel/perf_event_paranoid > 0. The change
>> to comm_exec can be observed by using -vv with
>> perf record and a kernel that supports comm_exec.
> Maybe I'm missing something - why not just try process-wide probing in
> the first place?

Same reason as patch 4 i.e. to avoid a jump label change when doing
system-wide tracing.

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