This is a note to let you know that I've just added the patch titled
tracing/hwlat: Honor the tracing_cpumask
to the 5.8-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
tracing-hwlat-honor-the-tracing_cpumask.patch
and it can be found in the queue-5.8 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 96b4833b6827a62c295b149213c68b559514c929 Mon Sep 17 00:00:00 2001
From: Kevin Hao <haokexin@xxxxxxxxx>
Date: Thu, 30 Jul 2020 16:23:18 +0800
Subject: tracing/hwlat: Honor the tracing_cpumask
From: Kevin Hao <haokexin@xxxxxxxxx>
commit 96b4833b6827a62c295b149213c68b559514c929 upstream.
In calculation of the cpu mask for the hwlat kernel thread, the wrong
cpu mask is used instead of the tracing_cpumask, this causes the
tracing/tracing_cpumask useless for hwlat tracer. Fixes it.
Link: https://lkml.kernel.org/r/20200730082318.42584-2-haokexin@xxxxxxxxx
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 0330f7aa8ee6 ("tracing: Have hwlat trace migrate across tracing_cpumask CPUs")
Signed-off-by: Kevin Hao <haokexin@xxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
kernel/trace/trace_hwlat.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/kernel/trace/trace_hwlat.c
+++ b/kernel/trace/trace_hwlat.c
@@ -283,6 +283,7 @@ static bool disable_migrate;
static void move_to_next_cpu(void)
{
struct cpumask *current_mask = &save_cpumask;
+ struct trace_array *tr = hwlat_trace;
int next_cpu;
if (disable_migrate)
@@ -296,7 +297,7 @@ static void move_to_next_cpu(void)
goto disable;
get_online_cpus();
- cpumask_and(current_mask, cpu_online_mask, tracing_buffer_mask);
+ cpumask_and(current_mask, cpu_online_mask, tr->tracing_cpumask);
next_cpu = cpumask_next(smp_processor_id(), current_mask);
put_online_cpus();
@@ -373,7 +374,7 @@ static int start_kthread(struct trace_ar
/* Just pick the first CPU on first iteration */
current_mask = &save_cpumask;
get_online_cpus();
- cpumask_and(current_mask, cpu_online_mask, tracing_buffer_mask);
+ cpumask_and(current_mask, cpu_online_mask, tr->tracing_cpumask);
put_online_cpus();
next_cpu = cpumask_first(current_mask);
Patches currently in stable-queue which might be from haokexin@xxxxxxxxx are
queue-5.8/tracing-hwlat-honor-the-tracing_cpumask.patch
