summaryrefslogtreecommitdiff
path: root/include/linux/sched.h
diff options
context:
space:
mode:
authorPhil Auld <pauld@redhat.com>2020-06-29 15:23:03 -0400
committerPeter Zijlstra <peterz@infradead.org>2020-07-08 11:39:02 +0200
commit9d246053a69196c7c27068870e9b4b66ac536f68 (patch)
tree25cd59b9266c05a1bd7aab1792d084860f2965f6 /include/linux/sched.h
parent07bbecb3410617816a99e76a2df7576507a0c8ad (diff)
sched: Add a tracepoint to track rq->nr_running
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> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200629192303.GC120228@lorien.usersys.redhat.com
Diffstat (limited to 'include/linux/sched.h')
-rw-r--r--include/linux/sched.h1
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 683372943093..12b10ce51a08 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -2044,6 +2044,7 @@ const struct sched_avg *sched_trace_rq_avg_dl(struct rq *rq);
const struct sched_avg *sched_trace_rq_avg_irq(struct rq *rq);
int sched_trace_rq_cpu(struct rq *rq);
+int sched_trace_rq_nr_running(struct rq *rq);
const struct cpumask *sched_trace_rd_span(struct root_domain *rd);