Messages in this thread | | | Date | Wed, 4 Sep 2019 07:39:15 -0400 | From | Steven Rostedt <> | Subject | Re: [PATCH v5 1/4] ftrace: Implement fs notification for tracing_max_latency |
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On Tue, 3 Sep 2019 15:25:59 +0200 Viktor Rosendahl <viktor.rosendahl@gmail.com> wrote:
> +void latency_fsnotify_stop(void) > +{ > + /* Make sure all CPUs see caller's previous actions to stop tracer */ > + smp_wmb();
These memory barriers just look wrong. What exactly are you trying to protect here?
Where's the matching rmbs?
-- Steve
> + static_branch_disable(&latency_notify_key); > + latency_fsnotify_process(); > +} > + > +void latency_fsnotify_start(void) > +{ > + static_branch_enable(&latency_notify_key); > + /* Make sure all CPUs see key value before caller continue */ > + smp_wmb(); > +} > +
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