linux-kernel - Re: [PATCH v8] Documentation: userspace-api: Document perf ring buffer mechanism

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: <CAM9d7cg3Qkx240RBGKYegeX-kxgUiQ4-G4R3sJBc=w=o-Msk=Q@mail.gmail.com>
Date: Fri, 5 Jan 2024 15:12:20 -0800
From: Namhyung Kim <namhyung@...nel.org>
To: Leo Yan <leo.yan@...aro.org>
Cc: Jonathan Corbet <corbet@....net>, Arnaldo Carvalho de Melo <acme@...nel.org>, Ian Rogers <irogers@...gle.com>, 
	Thomas Richter <tmricht@...ux.ibm.com>, Peter Zijlstra <peterz@...radead.org>, 
	Adrian Hunter <adrian.hunter@...el.com>, Jiri Olsa <jolsa@...nel.org>, 
	Ingo Molnar <mingo@...nel.org>, linux-doc@...r.kernel.org, linux-kernel@...r.kernel.org, 
	linux-perf-users@...r.kernel.org
Subject: Re: [PATCH v8] Documentation: userspace-api: Document perf ring
 buffer mechanism

Hi Leo,

On Tue, Jan 2, 2024 at 12:50 AM Leo Yan <leo.yan@...aro.org> wrote:
>
> In the Linux perf tool, the ring buffer serves not only as a medium for
> transferring PMU event data but also as a vital mechanism for hardware
> tracing using technologies like Intel PT and Arm CoreSight, etc.
>
> Consequently, the ring buffer mechanism plays a crucial role by ensuring
> high throughput for data transfer between the kernel and user space
> while avoiding excessive overhead caused by the ring buffer itself.
>
> This commit documents the ring buffer mechanism in detail.  It explains
> the implementation of both the regular ring buffer and the AUX ring
> buffer.  Additionally, it covers how these ring buffers support various
> tracing modes and explains the synchronization with memory barriers.
>
> Signed-off-by: Leo Yan <leo.yan@...aro.org>

Thanks a lot for working on this!

Reviewed-by: Namhyung Kim <namhyung@...nel.org>

Thanks,
Namhyung