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Date:   Tue, 2 Aug 2022 11:36:07 +0530
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Subject: Re: [RFC v2] perf: Rewrite core context handling
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To:     Peter Zijlstra <peterz@infradead.org>
Cc:     acme@kernel.org, alexander.shishkin@linux.intel.com,
        jolsa@redhat.com, namhyung@kernel.org, songliubraving@fb.com,
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        kim.phillips@amd.com, linux-kernel@vger.kernel.org,
        santosh.shukla@amd.com, ravi.bangoria@amd.com
References: <20220113134743.1292-1-ravi.bangoria@amd.com>
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From:   Ravi Bangoria <ravi.bangoria@amd.com>
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On 27-Jun-22 9:48 AM, Ravi Bangoria wrote:
> 
> On 13-Jun-22 8:05 PM, Peter Zijlstra wrote:
>>
>>
>> Right, so sorry for being incredibly tardy on this. Find below the
>> patch fwd ported to something recent.
>>
>> I'll reply to this with fixes and comments.
> 
> Thanks! I've resumed on this but my mind has lost all the context so
> it might take a while for me to reply to your comments. Please bear
> with me if I'm bit slow.

Sorry, it took a while for me to get started on it. Anyways, thanks for
providing fixes. I applied those and ran some tests on AMD Milan machine:

- Built in perf tests ran fine without any issues
- perf_event_tests reported one BUG_ON() and one WARN_ON(). I'll work on
  fixing those.
- Ran perf fuzzer for almost a day. It reported one softlockup but system
  recovered from it and later it reported one hardlockup but unfortunately
  my config had HARDLOCKUP_PANIC set and thus couldn't confirm whether that
  hardlockup was recoverable or not. Anyway, system was running pretty much
  fine until then.
- No lockdep warnings were observed in any of the tests.

I'll work on verifying functionality changes.

Thanks,
Ravi