Message-ID: <82a6f9b2-bb17-babd-fbe0-c4a5bec1203b@intel.com>
Date:   Wed, 22 Feb 2023 15:32:47 -0800
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From:   "Joseph, Jithu" <jithu.joseph@intel.com>
Subject: Re: [PATCH v2 4/7] platform/x86/intel/ifs: Implement Array BIST test
To:     Dave Hansen <dave.hansen@intel.com>, <hdegoede@redhat.com>,
        <markgross@kernel.org>
CC:     <tglx@linutronix.de>, <mingo@redhat.com>, <bp@alien8.de>,
        <dave.hansen@linux.intel.com>, <x86@kernel.org>, <hpa@zytor.com>,
        <gregkh@linuxfoundation.org>, <rostedt@goodmis.org>,
        <ashok.raj@intel.com>, <tony.luck@intel.com>,
        <linux-kernel@vger.kernel.org>,
        <platform-driver-x86@vger.kernel.org>, <patches@lists.linux.dev>,
        <ravi.v.shankar@intel.com>, <thiago.macieira@intel.com>,
        <athenas.jimenez.gonzalez@intel.com>, <sohil.mehta@intel.com>
References: <20230131234302.3997223-1-jithu.joseph@intel.com>
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On 2/22/2023 2:28 PM, Dave Hansen wrote:
> On 2/22/23 14:07, Joseph, Jithu wrote:
>> Since the trace has to be explicitly enabled (I thought it is okay to
>> add a more convenient custom one only to be enabled for detailed
>> analysis when required).
> 
> 	man perf-script
> 
> You should be able to write one to do exactly what you need in about 10
> minutes.  No new tracepoints, no new kernel code to maintain.  Knock

Thanks for the pointers. I gather that user level tools might be able to format the
msr trace output in a more convenient way (perhaps as generated by the custom driver trace)

There is still the other convenience of not having to look-up the
MSRs addresses corresponding to all the individual tests and setting the filter on them to
analyze IFS test activity (rather than enabling it via echo 1 > /sys/kernel/debug/tracing/events/intel_ifs/enable)

Agreed that for array test it is a single MSR. For other test, it is 2 separate MSRs ... there could be additional
tests in the future. 


Jithu