Re: [PATCH] perf sched: Rename switches to count and add usage description, options for latency

From: Madadi Vineeth Reddy
Date: Sun Apr 14 2024 - 22:31:42 EST


On 28/03/24 14:30, Madadi Vineeth Reddy wrote:
> Rename 'Switches' to 'Count' and document metrics shown for perf
> sched latency output. Also add options possible with perf sched
> latency.
>
> Initially, after seeing the output of 'perf sched latency', the term
> 'Switches' seemed like it's the number of context switches-in for a
> particular task, but upon going through the code, it was observed that
> it's actually keeping track of number of times a delay was calculated so
> that it is used in calculation of the average delay.
>
> Actually, the switches here is a subset of number of context switches-in
> because there are some cases where the count is not incremented in
> switch-in handler 'add_sched_in_event'. For example when a task is
> switched-in while it's state is not ready to run(!= THREAD_WAIT_CPU).
>
> commit d9340c1db3f5 ("perf sched: Display time in milliseconds, reorganize
> output") changed it from the original count to switches.
>
> So, renamed switches to count to make things a bit more clearer and
> added the metrics description of latency in the document.
>
> Signed-off-by: Madadi Vineeth Reddy <vineethr@xxxxxxxxxxxxx>
> ---

Hi Arnaldo,
Any comments on this patch?

Thanks and Regards
Madadi Vineeth Reddy