linux-kernel - Re: [PATCH] perf stat: Add event-interval-print option

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] [day] [month] [year] [list]

Message-ID: <20170824205158.GM2482@two.firstfloor.org>
Date:   Thu, 24 Aug 2017 13:51:59 -0700
From:   Andi Kleen <andi@...stfloor.org>
To:     Aaron Lindsay <alindsay@...eaurora.org>
Cc:     Peter Zijlstra <peterz@...radead.org>,
        Ingo Molnar <mingo@...hat.com>,
        Arnaldo Carvalho de Melo <acme@...nel.org>,
        Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
        linux-kernel@...r.kernel.org, Andi Kleen <andi@...stfloor.org>,
        Digant Desai <digantd@...eaurora.org>, timur@...eaurora.org
Subject: Re: [PATCH] perf stat: Add event-interval-print option

On Thu, Aug 24, 2017 at 04:39:02PM -0400, Aaron Lindsay wrote:
> Does anyone have any feedback on this patch or the idea in general?
> 
> Also, (for our bookkeeping - not trying to rush things) is there any
> chance this will still make it in for the 4.14 merge window, or is it
> 4.15 material at the earliest?

You can already do that with leader sampling through perf record

e.g. 

% perf record -e '{cpu/cpu-cycles,period=10000/,branches,branch-misses}:S' ...

% perf script
   swapper     0 [005] 3905226.804037:      10210 cpu/cpu-cycles,period=10000/:  ffffffff9e87643c intel_idle ([kernel.kallsyms])
         swapper     0 [005] 3905226.804037:        345                     branches:  ffffffff9e87643c intel_idle ([kernel.kallsyms])
         swapper     0 [005] 3905226.804037:         58                branch-misses:  ffffffff9e87643c intel_idle ([kernel.kallsyms])
          :16797 16797 [004] 3905226.804038:      10160 cpu/cpu-cycles,period=10000/:  ffffffffc07fdd10 kvm_fetch_guest_virt ([kvm])
          :16797 16797 [004] 3905226.804038:        515                     branches:  ffffffffc07fdd10 kvm_fetch_guest_virt ([kvm])
          :16797 16797 [004] 3905226.804038:         19                branch-misses:  ffffffffc07fdd10 kvm_fetch_guest_virt ([kvm])

Yes it's a useful technique.

-Andi