linux-kernel - Re: [PATCH v2 09/27] perf parse-events: Create two hybrid hardware events

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: Windows password security audit tool. GUI, reports in PDF.

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

Message-ID: <YE+avkajxbGJMOoM@krava>
Date:   Mon, 15 Mar 2021 18:34:54 +0100
From:   Jiri Olsa <jolsa@...hat.com>
To:     "Jin, Yao" <yao.jin@...ux.intel.com>
Cc:     acme@...nel.org, jolsa@...nel.org, peterz@...radead.org,
        mingo@...hat.com, alexander.shishkin@...ux.intel.com,
        Linux-kernel@...r.kernel.org, ak@...ux.intel.com,
        kan.liang@...el.com, yao.jin@...el.com
Subject: Re: [PATCH v2 09/27] perf parse-events: Create two hybrid hardware
 events

On Mon, Mar 15, 2021 at 10:04:56AM +0800, Jin, Yao wrote:
> Hi Jiri,
> 
> On 3/13/2021 3:15 AM, Jiri Olsa wrote:
> > On Thu, Mar 11, 2021 at 03:07:24PM +0800, Jin Yao wrote:
> > 
> > SNIP
> > 
> > >    cycles: 4: 800933425 1002536659 1002536659
> > >    cycles: 5: 800928573 1002528386 1002528386
> > >    cycles: 6: 800924347 1002520527 1002520527
> > >    cycles: 7: 800922009 1002513176 1002513176
> > >    cycles: 8: 800919624 1002507326 1002507326
> > >    cycles: 9: 800917204 1002500663 1002500663
> > >    cycles: 10: 802096579 1002494280 1002494280
> > >    cycles: 11: 802093770 1002486404 1002486404
> > >    cycles: 12: 803284338 1002479491 1002479491
> > >    cycles: 13: 803277609 1002469777 1002469777
> > >    cycles: 14: 800875902 1002458861 1002458861
> > >    cycles: 15: 800873241 1002451350 1002451350
> > >    cycles: 0: 800837379 1002444645 1002444645
> > >    cycles: 1: 800833400 1002438505 1002438505
> > >    cycles: 2: 800829291 1002433698 1002433698
> > >    cycles: 3: 800824390 1002427584 1002427584
> > >    cycles: 4: 800819360 1002422099 1002422099
> > >    cycles: 5: 800814787 1002415845 1002415845
> > >    cycles: 6: 800810125 1002410301 1002410301
> > >    cycles: 7: 800791893 1002386845 1002386845
> > >    cycles: 12855737722 16040169029 16040169029
> > >    cycles: 6406560625 8019379522 8019379522
> > > 
> > >     Performance counter stats for 'system wide':
> > > 
> > >        12,855,737,722      cpu_core/cycles/
> > >         6,406,560,625      cpu_atom/cycles/
> > 
> > so we do that no_merge stuff for uncore pmus, why can't we do
> > that in here? that'd seems like generic way
> > 
> > jirka
> > 
> 
> We have set the "stat_config.no_merge = true;" in "[PATCH v2 08/27] perf
> stat: Uniquify hybrid event name".
> 
> For hybrid hardware events, they have different configs. The config is
> 0xDD000000AA (0x400000000 for core vs. 0xa00000000 for atom in this example)
> 
> We use perf_pmu__for_each_hybrid_pmu() to iterate all hybrid PMUs, generate
> the configs and create the evsels for each hybrid PMU. This logic and the
> code are not complex and easy to understand.
> 
> Uncore looks complicated. It has uncore alias concept which is for different
> PMUs but with same prefix. Such as "uncore_cbox" for "uncore_cbox_0" to
> "uncore_cbox_9". But the uncore alias concept doesn't apply to hybrid pmu
> (we just have "cpu_core" and "cpu_atom" here). And actually I also don't
> want to mix the core stuff with uncore stuff, that would be hard for
> understanding.
> 
> Perhaps I misunderstand, correct me if I'm wrong.

not sure, I thought the merging stuff was more generic,
because the change looks too specific for me, I'll try
to check on it more deeply

jirka