linux-kernel - Re: [PATCH v2] sched/topology: Enable topology_span

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: <ZzzL1xmZIgUCNSFQ@swahl-home.5wahls.com>
Date: Tue, 19 Nov 2024 11:33:11 -0600
From: Steve Wahl <steve.wahl@....com>
To: K Prateek Nayak <kprateek.nayak@....com>
Cc: Saurabh Sengar <ssengar@...ux.microsoft.com>, mingo@...hat.com,
        peterz@...radead.org, juri.lelli@...hat.com,
        vincent.guittot@...aro.org, dietmar.eggemann@....com,
        rostedt@...dmis.org, bsegall@...gle.com, mgorman@...e.de,
        vschneid@...hat.com, linux-kernel@...r.kernel.org,
        Steve Wahl <steve.wahl@....com>, stable@...r.kernel.org,
        ssengar@...rosoft.com, srivatsa@...il.mit.edu
Subject: Re: [PATCH v2] sched/topology: Enable topology_span_sane check only
 for debug builds

On Tue, Nov 19, 2024 at 11:54:57AM +0530, K Prateek Nayak wrote:
> (+ Steve)
> 
> Hello Saurabh,
> On 11/18/2024 3:09 PM, Saurabh Sengar wrote:
> > On a x86 system under test with 1780 CPUs, topology_span_sane() takes
> > around 8 seconds cumulatively for all the iterations. It is an expensive
> > operation which does the sanity of non-NUMA topology masks.
> 
> Steve too was optimizing this path. I believe his latest version can be
> found at:
> https://lore.kernel.org/lkml/20241031200431.182443-1-steve.wahl@hpe.com/

Yes, Saurabh, I'd be very interested in whether my current patch
relieves your situation.

Thanks,

--> Steve Wahl


-- 
Steve Wahl, Hewlett Packard Enterprise