Re: [PATCH] coresight: tmc-etr: Don't enable ETR when it's not ready

From: James Clark
Date: Wed Jan 25 2023 - 05:21:24 EST




On 24/01/2023 20:09, Yabin Cui wrote:
> Ping for review. And I still can't reproduce it, even if I reduced the
> timeout to 2us and tried different workloads. Any suggestions for how
> to reproduce it?
>

Hi Yabin,

I just found this in my kernel log files from a few days ago.

Jan 19 15:03:35 n1-sdp kernel: [865337.521413] coresight tmc_etr0:
timeout while waiting for completion of Manual Flush
Jan 19 15:03:35 n1-sdp kernel: [865337.529351] coresight tmc_etr0:
timeout while waiting for TMC to be Ready

This is on N1SDP, and I've only been running "normal" perf commands like:

perf record -e cs_etm//k -- taskset -c 2 sleep 1
perf record -e cs_etm// -- stress -c 2 -t 1

I also haven't been able to reproduce it since

James