Re: [PATCH v2] Sched: Add a tracepoint to track rq->nr_running

[Qais Yousef <qais.yousef@arm.com>]

On 06/29/20 15:23, Phil Auld wrote:
> Add a bare tracepoint trace_sched_update_nr_running_tp which tracks
> ->nr_running CPU's rq. This is used to accurately trace this data and
> provide a visualization of scheduler imbalances in, for example, the
> form of a heat map.  The tracepoint is accessed by loading an external
> kernel module. An example module (forked from Qais' module and including
> the pelt related tracepoints) can be found at:
> 
>   https://github.com/auldp/tracepoints-helpers.git
> 
> A script to turn the trace-cmd report output into a heatmap plot can be
> found at:
> 
>   https://github.com/jirvoz/plot-nr-running
> 
> The tracepoints are added to add_nr_running() and sub_nr_running() which
> are in kernel/sched/sched.h. In order to avoid CREATE_TRACE_POINTS in
> the header a wrapper call is used and the trace/events/sched.h include
> is moved before sched.h in kernel/sched/core.
> 
> Signed-off-by: Phil Auld <pauld@redhat.com>
> CC: Qais Yousef <qais.yousef@arm.com>
> CC: Ingo Molnar <mingo@redhat.com>
> CC: Peter Zijlstra <peterz@infradead.org>
> CC: Vincent Guittot <vincent.guittot@linaro.org>
> CC: Steven Rostedt <rostedt@goodmis.org>
> CC: linux-kernel@vger.kernel.org
> ---

LGTM.

Reviewed-by: Qais Yousef <qais.yousef@arm.com>

Thanks

--
Qais Yousef