Backport In-Memory Collection Counters (IMC) trace-mode patches

[bugproxy]

== Comment: #0 - Murilo Opsfelder Araujo - 2019-11-08 06:30:06 ==
---Problem Description---
The following patches may be wanted in >= Bionic kernels:

1. powerpc/include: Add data structures and macros for IMC trace mode
    https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/commit/?h=next&id=d1720adff3783a2ba7c128e304a385d18962835b

2. powerpc/perf: Rearrange setting of ldbar for thread-imc
    https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/commit/?h=next&id=dd50cf7cbc7bdd86483b797ac3d27b37d5aeeaa4

3. powerpc/perf: Add privileged access check for thread_imc
    https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/commit/?h=next&id=216c3087a346db8d7c8a064d2b8f0f49e4694934

4. powerpc/perf: Trace imc events detection and cpuhotplug
    https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/commit/?h=next&id=72c69dcddce103338de558c5c6e9ef9e4f607ce1

5. powerpc/perf: Trace imc PMU functions
    https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/commit/?h=next&id=012ae244845f19d5f6ca2a90426851bc5044a0dc

Patch #3 addresses a security issue.

---uname output---
na

Machine Type = na

---Debugger---
A debugger is not configured

Stack trace output:
 no

Oops output:
 no

System Dump Info:
  The system is not configured to capture a system dump.

== Comment: #12 - Murilo Opsfelder Araujo - 2019-11-22 07:41:20 ==
Please mirror to Canonical to backporting this single patch for >= Bionic kernels (or for which kernels they find appropriate):

https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/commit/?id=216c3087a346db8d7c8a064d2b8f0f49e4694934

commit 216c3087a346db8d7c8a064d2b8f0f49e4694934
Author: Madhavan Srinivasan <email address hidden>
Date: Tue Apr 16 15:18:29 2019 +0530

    powerpc/perf: Add privileged access check for thread_imc

[Manoj Iyer (manjo)]

Since this is not a critical bug fix or regression this might not be a candidate for LTS Bionic kernel.

[Manoj Iyer (manjo)]

IBM,

Please test the Disco kernel available in https://launchpad.net/~ubuntu-power-triage/+archive/ubuntu/lp1854071/

Also, please share following details

1. What impact does it have without these patches?
2. The testcase used, and how to run the tests.

Thanks

[bugproxy (bugproxy)]

------- Comment From <email address hidden> 2020-01-24 08:36 EDT-------
(In reply to comment #16)
> IBM,
>
> Please test the Disco kernel available in
> https://launchpad.net/~ubuntu-power-triage/+archive/ubuntu/lp1854071/
>
> Also, please share following details
>
> 1. What impact does it have without these patches?

Anju and Madhavan,

As authors of these patches, could you please help Canonical understand the
impact of such patches?

> 2. The testcase used, and how to run the tests.

Example of commands to read trace_imc events:

# perf kvm record -e trace_imc/trace_cycles <application>
# perf kvm record -e trace_cycles
# perf record -e trace_imc/trace_cycles <application>

>
> Thanks

Thank you!

Murilo

[Frank Heimes (fheimes)]

Since Ubuntu 19.04 / Disco reached it's end-of-life on January the 23rd:
https://lists.ubuntu.com/archives/ubuntu-announce/2020-January/000253.html
the entry that marks this ticket as affecting 'Disco' is changed to 'Won't Fix'
and with that the overall status got adjusted.

[Frank Heimes (fheimes)]

Please notice that all patches needed (and mentioned above) are already in 19.10 / Eoan and in Focal.

[bugproxy (bugproxy)]

------- Comment From <email address hidden> 2020-01-27 11:31 EDT-------
(In reply to comment #18)
> Since Ubuntu 19.04 / Disco reached it's end-of-life on January the 23rd:
> https://lists.ubuntu.com/archives/ubuntu-announce/2020-January/000253.html
> the entry that marks this ticket as affecting 'Disco' is changed to 'Won't
> Fix'
> and with that the overall status got adjusted.
>
> Please notice that all patches needed (and mentioned above) are already in
> 19.10 / Eoan and in Focal.

Murilo:
Based on previous comments, is anything else needed for this issue?