From: Srivatsa S. Bhat (VMware) Date: Thu, 10 Oct 2019 18:51:01 +0000 (-0700) Subject: tracing/hwlat: Don't ignore outer-loop duration when calculating max_latency X-Git-Tag: v5.4-rc3~1^2~1 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=fc64e4ad80d4b72efce116f87b3174f0b7196f8e;p=platform%2Fkernel%2Flinux-rpi.git tracing/hwlat: Don't ignore outer-loop duration when calculating max_latency max_latency is intended to record the maximum ever observed hardware latency, which may occur in either part of the loop (inner/outer). So we need to also consider the outer-loop sample when updating max_latency. Link: http://lkml.kernel.org/r/157073345463.17189.18124025522664682811.stgit@srivatsa-ubuntu Fixes: e7c15cd8a113 ("tracing: Added hardware latency tracer") Cc: stable@vger.kernel.org Signed-off-by: Srivatsa S. Bhat (VMware) Signed-off-by: Steven Rostedt (VMware) --- diff --git a/kernel/trace/trace_hwlat.c b/kernel/trace/trace_hwlat.c index a0251a7..862f4b0 100644 --- a/kernel/trace/trace_hwlat.c +++ b/kernel/trace/trace_hwlat.c @@ -256,6 +256,8 @@ static int get_sample(void) /* Keep a running maximum ever recorded hardware latency */ if (sample > tr->max_latency) tr->max_latency = sample; + if (outer_sample > tr->max_latency) + tr->max_latency = outer_sample; } out: