linux-kernel - Re: [PATCH v5 3/5] perf tools: sync addition of PERF_MEM_SNOOPX

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: <47ec29fe-75ea-62ef-447b-1164569616de@arm.com>
Date:   Mon, 11 Apr 2022 15:35:52 +0100
From:   German Gomez <german.gomez@....com>
To:     Ali Saidi <alisaidi@...zon.com>, linux-kernel@...r.kernel.org,
        linux-perf-users@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org, leo.yan@...aro.org,
        acme@...nel.org
Cc:     benh@...nel.crashing.org, Nick.Forrington@....com,
        alexander.shishkin@...ux.intel.com, andrew.kilroy@....com,
        james.clark@....com, john.garry@...wei.com, jolsa@...nel.org,
        kjain@...ux.ibm.com, lihuafei1@...wei.com, mark.rutland@....com,
        mathieu.poirier@...aro.org, mingo@...hat.com, namhyung@...nel.org,
        peterz@...radead.org, will@...nel.org
Subject: Re: [PATCH v5 3/5] perf tools: sync addition of PERF_MEM_SNOOPX_PEER


On 11/04/2022 11:26, German Gomez wrote:
> On 08/04/2022 20:53, Ali Saidi wrote:
>> Add a flag to the perf mem data struct to signal that a request caused a
>> cache-to-cache transfer of a line from a peer of the requestor and
>> wasn't sourced from a lower cache level.  The line being moved from one
>> peer cache to another has latency and performance implications. On Arm64
>> Neoverse systems the data source can indicate a cache-to-cache transfer
>> but not if the line is dirty or clean, so instead of overloading HITM
>> define a new flag that indicates this type of transfer.
> I think it's fine to merge this and the previous commit rather than have
> two commits with the same msg.
>

I take it back. It has been pointed out to me that having the separation
is normal/ok. So my comment doesn't apply.