Re: [PATCH] Documentation: coresight: Update the generic device names

[Suzuki K Poulose <suzuki.poulose@arm.com>]

Hi Mathieu,

On 03/06/2019 20:01, Mathieu Poirier wrote:
> Hi Suzuki,
> 
> On Thu, May 30, 2019 at 04:11:17PM +0100, Suzuki K Poulose wrote:
>> Update the documentation to reflect the new naming scheme with
>> latest changes.
>>
>> Reported-by: Leo Yan <leo.yan@linaro.org>
>> Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
>> Cc: Jonathan Corbet <corbet@lwn.net>
>> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
>> ---
>>   Documentation/trace/coresight.txt | 34 +++++++++++++++++++---------------
>>   1 file changed, 19 insertions(+), 15 deletions(-)
>>
>> diff --git a/Documentation/trace/coresight.txt b/Documentation/trace/coresight.txt
>> index efbc832..7b427cf 100644
>> --- a/Documentation/trace/coresight.txt
>> +++ b/Documentation/trace/coresight.txt
>> @@ -326,16 +326,20 @@ amount of processor cores), the "cs_etm" PMU will be listed only once.
>>   A Coresight PMU works the same way as any other PMU, i.e the name of the PMU is
>>   listed along with configuration options within forward slashes '/'.  Since a
>>   Coresight system will typically have more than one sink, the name of the sink to
>> -work with needs to be specified as an event option.  Names for sink to choose
>> -from are listed in sysFS under ($SYSFS)/bus/coresight/devices:
>> +work with needs to be specified as an event option.
>> +On newer kernels the available sinks are listed in sysFS under:
>> +($SYSFS)/bus/event_source/devices/cs_etm/sinks/
>>   
>> -	root@linaro-nano:~# ls /sys/bus/coresight/devices/
>> -		20010000.etf   20040000.funnel  20100000.stm  22040000.etm
>> -		22140000.etm  230c0000.funnel  23240000.etm 20030000.tpiu
>> -		20070000.etr     20120000.replicator  220c0000.funnel
>> -		23040000.etm  23140000.etm     23340000.etm
>> +	root@localhost:/sys/bus/event_source/devices/cs_etm/sinks# ls
>> +	tmc_etf0  tmc_etr0  tpiu0
>>   
>> -	root@linaro-nano:~# perf record -e cs_etm/@20070000.etr/u --per-thread program
>> +On older kernels, this may need to be found from the list of coresight devices,
>> +available under ($SYSFS)/bus/coresight/devices/:
>> +
>> +	root@localhost:/sys/bus/coresight/devices# ls
>> +	etm0  etm1  etm2  etm3  etm4  etm5  funnel0  funnel1  funnel2  replicator0  stm0 tmc_etf0  tmc_etr0  tpiu0
>> +
>> +	root@linaro-nano:~# perf record -e cs_etm/@tmc_etr0/u --per-thread program
> 
> On the "older" kernels you are referring to one would find the original naming
> convention.  Everything else looks good to me.

True, but do we care what we see there ? All we care about is the location,
where to find them. I could fix it, if you think thats needed.

Cheers
Suzuki