linux-kernel - Re: [External] : [RFC PATCH v2 1/6] perf vendor events arm64: Add topdown L1 metrics for neoverse-n2

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 21 Nov 2022 23:17:11 +0800
From:   Jing Zhang <renyu.zj@...ux.alibaba.com>
To:     John Garry <john.g.garry@...cle.com>,
        linux-arm-kernel@...ts.infradead.org,
        linux-perf-users@...r.kernel.org, linux-kernel@...r.kernel.org,
        John Garry <john.garry@...wei.com>,
        Will Deacon <will@...nel.org>,
        James Clark <james.clark@....com>,
        Mike Leach <mike.leach@...aro.org>,
        Leo Yan <leo.yan@...aro.org>, Ian Rogers <irogers@...gle.com>
Cc:     Peter Zijlstra <peterz@...radead.org>,
        Ingo Molnar <mingo@...hat.com>,
        Arnaldo Carvalho de Melo <acme@...nel.org>,
        Mark Rutland <mark.rutland@....com>,
        Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
        Jiri Olsa <jolsa@...nel.org>,
        Namhyung Kim <namhyung@...nel.org>,
        Andrew Kilroy <andrew.kilroy@....com>,
        Shuai Xue <xueshuai@...ux.alibaba.com>,
        Zhuo Song <zhuo.song@...ux.alibaba.com>
Subject: Re: [External] : [RFC PATCH v2 1/6] perf vendor events arm64: Add
 topdown L1 metrics for neoverse-n2



在 2022/11/21 下午6:22, John Garry 写道:
> 
>>
>>
>> #./perf stat -e FRONTEND_BOUND sleep 1
>> event syntax error: 'FRONTEND_BOUND'
> 
> For metrics, use -M, not -e
> 
> If this doesn't help, verify generated pmu-events/pmu-events.c is same after you make the change to try to use std arch events for metrics. Note that I never tested running my change.
> 
> Thanks,
> John
> 
>>                       \___ parser error
>> Run 'perf list' for a list of valid events
>>
>>   Usage: perf stat [<options>] [<command>]
>>
>>      -e, --event <event>   event selector. use 'perf list' to list available events
>>
>>
>>
>> diff --git a/tools/perf/pmu-events/arch/arm64/arm/neoverse-n2/pipeline.json b/tools/perf/pmu-events/arch/arm64/arm/neoverse-n2/pipeli
>> index f9fae15..1089ca0 100644
>> --- a/tools/perf/pmu-events/arch/arm64/arm/neoverse-n2/pipeline.json
>> +++ b/tools/perf/pmu-events/arch/arm64/arm/neoverse-n2/pipeline.json
>> @@ -6,18 +6,24 @@
>>           "ArchStdEvent": "STALL_BACKEND"
>>       },
>>       {
>> -        "ArchStdEvent": "STALL_SLOT_FRONTEND"
>> +        "ArchStdEvent": "STALL_SLOT_FRONTEND",
>> +        "MetricExpr": "STALL_SLOT_FRONTEND - CPU_CYCLES"
>>       },
>>       {
>>


I'm sorry that I misunderstood the purpose of putting metric as arch_std_event at first,
and now it works after the modification over your suggestion.

But there are also a few questions:

1. The value of the slot in the topdownL1 is various in different architectures, for example,
the slot is 5 on neoverse-n2. If I put topdownL1 metric as arch_std_event, then I need to
specify the slot to 5 in n2. I can specify slot values in metric like below, but is there any
other concise way to do this?

diff --git a/tools/perf/pmu-events/arch/arm64/arm/neoverse-n2/metrics.json b/tools/perf/pmu-events/arch/arm64/arm/neoverse-n2/metrics.json
index 8ff1dfe..b473baf 100644
--- a/tools/perf/pmu-events/arch/arm64/arm/neoverse-n2/metrics.json
+++ b/tools/perf/pmu-events/arch/arm64/arm/neoverse-n2/metrics.json
@@ -1,4 +1,23 @@
[
+       {
+               "MetricExpr": "5",
+               "PublicDescription": "A pipeline slot represents the hardware resources needed to process one uOp",
+               "BriefDescription": "A pipeline slot represents the hardware resources needed to process one uOp",
+               "MetricName": "slot"
+       },
+       {
+               "ArchStdEvent": "FRONTEND_BOUND"
+       },
+       {
+               "ArchStdEvent": "BACKEND_BOUND"
+       },
+       {
+               "ArchStdEvent": "WASTED"
+       },
+       {
+               "ArchStdEvent": "RETIRING"
+       },


2. Should I add the topdownL1 metric to tools/perf/pmu-event/recommended.json,
or create a new json file to place the general metric?

Looking forward to your reply.

Thanks,
Jing