From: Anshuman Khandual <khandual@linux.vnet.ibm.com>
To: Stephane Eranian <eranian@google.com>
Cc: linux-kernel@vger.kernel.org, peterz@infradead.org, mingo@elte.hu
Subject: Use case for PERF_COUNT_HW_REF_CPU_CYCLES generic PMU event
Date: Wed, 08 Feb 2012 15:13:48 +0530 [thread overview]
Message-ID: <4F3243D4.4080907@linux.vnet.ibm.com> (raw)
Hello Stephane,
I was going through the following discussion where we added the
new HW generic event PERF_COUNT_HW_REF_CPU_CYCLES.
https://lkml.org/lkml/2011/12/10/103
(Sorry, for asking this question bit late)
I am trying to understand the use case for this. Would this new event
help us in generating (during a perf session) a CPU frequency invariant
time metric against which we would plot our other perf event's measurements ?
CPU frequency independent time measurement is it's primary purpose ? or we were
finding a way to expose the fixed counter 2 which was not getting used before
for not having an event encoding. I guess this would help us in finding equivalent
PMU events or mechanisms in other architecture / platforms.
--
Anshuman Khandual
Linux Technology Centre
IBM Systems and Technology Group
next reply other threads:[~2012-02-08 9:44 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-02-08 9:43 Anshuman Khandual [this message]
2012-02-08 9:51 ` Use case for PERF_COUNT_HW_REF_CPU_CYCLES generic PMU event Stephane Eranian
2012-02-08 10:51 ` Anshuman Khandual
2012-02-08 11:08 ` Stephane Eranian
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