Hi Steven, Thanks for your reply:) -----Original Message----- From: Steven Rostedt [mailto:rost...@goodmis.org] Sent: Friday, September 18, 2020 8:31 AM To: tianxianting (RD) <tian.xiant...@h3c.com> Cc: mi...@redhat.com; linux-kernel@vger.kernel.org Subject: Re: [PATCH] tracing: use __this_cpu_read() in trace_buffered_event_enable()
Sorry for the late reply (been busy with Linux Plumbers, took a vacation, and then trying to catch up on all my email for the last two months!) But I just wanted to let you know that I added this to my queue. Thanks! -- Steve On Thu, 13 Aug 2020 19:28:03 +0800 Xianting Tian <tian.xiant...@h3c.com> wrote: > The code is executed with preemption disabled, so it's safe to use > __this_cpu_read(). > > Signed-off-by: Xianting Tian <tian.xiant...@h3c.com> > --- > kernel/trace/trace.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index > bb6226972..7d0d71ce9 100644 > --- a/kernel/trace/trace.c > +++ b/kernel/trace/trace.c > @@ -2514,7 +2514,7 @@ void trace_buffered_event_enable(void) > > preempt_disable(); > if (cpu == smp_processor_id() && > - this_cpu_read(trace_buffered_event) != > + __this_cpu_read(trace_buffered_event) != > per_cpu(trace_buffered_event, cpu)) > WARN_ON_ONCE(1); > preempt_enable();
