Re: [PATCH 1/2] Documentation: tracing: Documentation for ultrasoc SMB drivers

From: liuqi (BA)
Date: Mon Sep 06 2021 - 23:32:55 EST


Hi Mathieu,

On 2021/9/7 1:34, Mathieu Poirier wrote:
On Mon, Jul 19, 2021 at 07:17:36PM +0800, Qi Liu wrote:
Ultrasoc trace module is a system level solution for tracing, and SMB
is the component in trace module to store trace message. This patch
brings in a documentation for ultrasoc SMB driver and simple introduces
how to use ultrasoc SMB by sysfs interface and perf interface.

Signed-off-by: Qi Liu <liuqi115@xxxxxxxxxx>

+Example usage of perf::
+
+ $# ./perf list pmu
+ cs_etm// [Kernel PMU event]
+ $# ./perf record -e cs_etm/@sink_smb0/ -C 0 --per-thread sleep 2s
+ [ perf record: Woken up 2 times to write data ]
+ [ perf record: Captured and wrote 0.288 MB perf.data ]
+ $# ./perf report

This IP block works like any other sink device and as such I don't really see a
need for this documentation - especially since it is mostly conveying the same
information already present in coresight.rst.


Yes, smb works as a sink device.
got it, I'll drop this documentation next time.

Thanks,
Qi

Thanks,
Mathieu
>> --
2.17.1

.