Red Hat Bugzilla – Bug 463365
[LTC 6.0 FEAT] 200974:Kernel interface to performance monitor unit
Last modified: 2010-11-11 09:41:33 EST
Emily J. Ratliff <email@example.com> - 2008-09-16 18:29 EDT
1. Feature Overview:
Feature Id: 
a. Name of Feature: Perfmon2 kernel interface to PMU
b. Feature Description
Perfmon2 is the new (converged) 'hardware-based performance monitoring interface for Linux' kernel.
It is an open source project whose maintainer is Stephan Eranian from HP. There's been increasing
interest in getting a standard kernel interface to performance monitor units (PMUs) into mainline
kernel, and Perfmon2 appears to have the necessary community support. Not in mainline yet, but
Andrew Morton wants to see a push to get it in.
2. Feature Details:
Arch Specificity: Both
Affects Core Kernel: Yes
Delivery Mechanism: Direct from community
Request Type: Toolchain - Enhancement from Upstream
d. Upstream Acceptance: Submitted
Sponsor Priority 2
f. Severity: Medium
IBM Confidential: no
Code Contribution: IBM code
g. Component Version Target: 2.6.27
3. Business Case
Performance analysis tools rely on a kernel interface to the PMU. OProfile has the oprofile kernel
driver already in mainline, but other tools (e.g., PAPI) rely on various non-mainline PMU interface
software that must be patched into the kernel. This reliance on non-mainline kernel code has
prevented including PAPI (and possibly other tools) in the distros. Including PAPI in the distros
would be beneficial, especially to the high performance computing community where PAPI is very popular.
4. Primary contact at Red Hat:
5. Primary contacts at Partner:
Project Management Contact:
Michael Hohnbaum, firstname.lastname@example.org, 503-578-5486
Steven Munroe, email@example.com
Maynard Johnson, firstname.lastname@example.org
Alexander Johnson, email@example.com
This has a target of 2.6.27 set, but as I understand it, perfmon2 is *not* actually in 2.6.27. Correct?
Correct. Perfmon2 did not make it into 2.6.27. Outlook is uncertain as to what kernel version this will be accepted into. We are actively working with the community to gain mainline acceptance.
------- Comment From firstname.lastname@example.org 2009-08-31 15:40 EDT-------
Hello, Red Hat,
I changed the summary description of this feature request to:
"Kernel interface to performance monitor unit"
Please change the summary description on the Red Hat side as well.
This generic feature description allows for the more likely case that the "Performance Counters for Linux" interface (aka "perf_counters" or "PCL") will be included in RHEL 6, since it's been accepted into mainline and will be included in 2.6.31. PCL would satisfy this feature request. Thank you.
------- Comment From email@example.com 2009-08-31 15:44 EDT-------
No patch is attached to this bugzilla, on the assumption that RHEL 6 will be based on a kernel version that includes PCL.
OK, setting to MODIFIED based on the PCL comment.
The feature requested has already been accepted into the upstream code base
planned for the next major release of Red Hat Enterprise Linux.
When the next milestone release of Red Hat Enterprise Linux 6 is available,
please verify that the feature requested is present and functioning as
PCL will be included in RHEL 6 in lieu of perfmon2.
------- Comment From firstname.lastname@example.org 2010-04-27 14:34 EDT-------
I've verified this feature is present in RHEL6 beta1. Thank you.
Verified in 2.6.32-25.el6.ppc64. The feature is present.
Red Hat Enterprise Linux 6.0 is now available and should resolve
the problem described in this bug report. This report is therefore being closed
with a resolution of CURRENTRELEASE. You may reopen this bug report if the
solution does not work for you.