tracing/hwlat: Honor the tracing_cpumask (96b4833b) · Commits · 戴 / test

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@gmail.com Cc: Ingo Molnar <mingo@redhat.com> Cc: stable@vger.kernel.org Fixes: ("tracing: Have hwlat trace migrate across tracing_cpumask CPUs") Signed-off-by:

Kevin Hao <haokexin@gmail.com> Signed-off-by:

Steven Rostedt (VMware) <rostedt@goodmis.org>

kernel/trace/trace_hwlat.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -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();

		@@ -372,7 +373,7 @@ static int start_kthread(struct trace_array *tr)

		/* Just pick the first CPU on first iteration */
		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);

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