Re: [PATCH v3] perf doc: Document ring buffer mechanism

[Ingo Molnar]

* Ingo Molnar <mingo@xxxxxxxxxx> wrote:

> 
> * Leo Yan <leo.yan@xxxxxxxxxx> 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 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@xxxxxxxxxx>
> > ---
> > 
> > Changes from v2:
> > - Refined doc for Thomas's suggestions (Thomas Richter).
> > 
> > Changes from v1:
> > - Addressed Ian's comments and suggestions (Ian Rogers).
> > 
> > 
> >  tools/perf/Documentation/perf-ring-buffer.txt | 762 ++++++++++++++++++
> >  1 file changed, 762 insertions(+)
> >  create mode 100644 tools/perf/Documentation/perf-ring-buffer.txt
> 
> Nice addition!
> 
> If it hasn't been picked up yet:
> 
>   Acked-by: Ingo Molnar <mingo@xxxxxxxxxx>

Note that my ack is conditional on the conversion to RST and moving to 
Documentation/ - this documents an important aspect of the primary perf 
ABI, it deserves to be on the kernel side.

Thanks,

	Ingo