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Message-ID: <b5095128-2b10-4bd2-98aa-d5b04f412fc9@amd.com>
Date:   Thu, 14 Sep 2023 14:44:19 +0530
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Subject: Re: [PATCH] perf/x86/amd: Do not WARN on every IRQ
Content-Language: en-US
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Jirka Hladky <jhladky@redhat.com>,
        Breno Leitao <leitao@debian.org>,
        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jiri Olsa <jolsa@kernel.org>,
        Namhyung Kim <namhyung@kernel.org>,
        Ian Rogers <irogers@google.com>,
        Adrian Hunter <adrian.hunter@intel.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>, leit@fb.com,
        dcostantino@meta.com,
        "open list:PERFORMANCE EVENTS SUBSYSTEM" 
        <linux-perf-users@vger.kernel.org>,
        "open list:PERFORMANCE EVENTS SUBSYSTEM" 
        <linux-kernel@vger.kernel.org>
References: <20230616115316.3652155-1-leitao@debian.org>
 <20230616132954.GG4253@hirez.programming.kicks-ass.net>
 <ZQHiJxHSSGNk+ul5@gmail.com>
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 <f06ef3dd-dd71-4ba4-a4fa-18a08788c035@amd.com>
 <20230914091234.GE16631@noisy.programming.kicks-ass.net>
From:   Sandipan Das <sandipan.das@amd.com>
In-Reply-To: <20230914091234.GE16631@noisy.programming.kicks-ass.net>
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On 9/14/2023 2:42 PM, Peter Zijlstra wrote:
> On Thu, Sep 14, 2023 at 02:25:40PM +0530, Sandipan Das wrote:
>> Hi Breno, Jirka,
>>
>> On 9/14/2023 2:15 PM, Jirka Hladky wrote:
>>> Hi Breno,
>>>
>>> I'm definitively voting for using WARN_ON_ONCE - in the current
>>> implementation, we are getting thousands of the same warnings and Call
>>> Traces, causing the system to become unusable.
>>>
>>>> Anyway, please let me know whatever is your preferred way and I will submit a v2.
>>> @Peter Zijlstra and @Sandipan - could you please comment on the
>>> preferred implementation of the patch?
>>>
>>
>> I agree with using WARN_ON_ONCE() to make this less intrusive.
> 
> Could you send a patch that AMD is happy with? I think you wrote this
> was a firmware bug and is sorted with a new firmware, so perhaps make it
> WARN_ONCE() and tell the users to upgrade their firmware to $ver ?

Sure. Will do.