Thread (21 messages) 21 messages, 5 authors, 2021-06-28

Re: [PATCH v1 0/3] coresight: Fix for snapshot mode

From: Leo Yan <hidden>
Date: 2021-06-12 03:28:47
Also in: linux-perf-users, lkml

On Fri, Jun 11, 2021 at 01:31:41AM -0700, Denis Nikitin wrote:
Hi Suzuki,

On Thu, Jun 10, 2021 at 9:04 AM Suzuki K Poulose [off-list ref] wrote:
quoted
[...]
quoted
Are you able to confirm if the patch 3 alone fixes the above issue ?
I am not convinced that Patch 1 is necessary.
Yes. "perf cs-etm: Remove callback cs_etm_find_snapshot()" alone fixes
the issue.
Based on current testing result, we should give high priority for
patches 2 and 3.

The patch 1 is controversial for how to handle the trace data kept
in multiple AUX buffers; essentially it's up to how we understand the
snapshot definition.  I confirmed Intel-PT and CoreSight have the same
behaviour for capturing trace data from multiple AUX ring buffers when
snapshot occurs.

I'd like to leave patch 1/3 out, and resend it if we get conclusion.
At the meantime, @Denis, if you have observed any profiling result
(or profiling quality) difference caused by patch 1, the feedback would
be very valuable.

Thanks a lot for Denis' testing and insight review from Suzuki!

Leo

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help