Messages in this thread | | | Date | Fri, 4 Aug 2023 17:10:27 +0800 | From | Leo Yan <> | Subject | Re: [PATCH v2] perf doc: Document ring buffer mechanism |
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On Thu, Aug 03, 2023 at 05:53:29PM -0300, Arnaldo Carvalho de Melo wrote: > Em Fri, Aug 04, 2023 at 12:56:36AM +0800, Leo Yan escreveu: > > Hi Jon, > > > > On Thu, Aug 03, 2023 at 08:34:50AM -0600, Jonathan Corbet wrote: > > > Leo Yan <leo.yan@linaro.org> writes: > > > > > > > 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 provides > > > > an in-depth explanation of the implementation of both the generic 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@linaro.org> > > > > --- > > > > > > So this seems like good material from a very brief scan. I do have to > > > ask, though: why is it not in RST, and why not put it into the > > > user-space API book? > > > > This documentation is Perf related topic, so my instinct is to place > > it into the folder tools/perf/Documentation/. > > > > Strictly to say, the doc doesn't give formal introduction for the > > user-space APIs. Given perf ring buffer is a mechanism for exchanging > > data between the kernel and user space, I am open for placing it in the > > folder Documentation/userspace-api/. > > > > I would like get opinions from the perf maintainers if possible, if we > > have agreenment I am glad to convert it to RST format. > > Yeah, I agree with Jon.
Okay, I will spin a new patch based on this discussion.
Thanks for confirmation.
Leo
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