linux-kernel - Re: [PATCH V6 09/14] perf/x86/intel: Support TopDown metrics on Ice Lake

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]

Date:   Tue, 21 Jul 2020 21:20:02 +0200
From:   Peter Zijlstra <peterz@...radead.org>
To:     Andi Kleen <ak@...ux.intel.com>
Cc:     kan.liang@...ux.intel.com, acme@...hat.com, mingo@...nel.org,
        linux-kernel@...r.kernel.org, jolsa@...nel.org, eranian@...gle.com,
        alexander.shishkin@...ux.intel.com
Subject: Re: [PATCH V6 09/14] perf/x86/intel: Support TopDown metrics on Ice
 Lake

On Tue, Jul 21, 2020 at 10:38:59AM -0700, Andi Kleen wrote:
> > Also, that for_each_set_bit() loop, trying to find the events to
> > update...
> > 
> > Can't we, instead, make the SLOTS update advance 5 running counters in
> > cpuc and feed the events off of that?
> 
> The original patches implemented this through a perf transaction and a
> cache.  I think what you're suggesting is similar to the old cache.

I can't remember :-) Anyway, the TXN_READ thing Kan pointed out should
work fine, I just missed it when reading through the code.