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Date:   Wed, 29 May 2019 09:58:52 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Daniel Bristot de Oliveira <bristot@redhat.com>,
        linux-kernel@vger.kernel.org, williams@redhat.com,
        daniel@bristot.me, Ingo Molnar <mingo@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        Matthias Kaehlcke <mka@chromium.org>,
        "Joel Fernandes (Google)" <joel@joelfernandes.org>,
        Frederic Weisbecker <frederic@kernel.org>,
        Yangtao Li <tiny.windzz@gmail.com>,
        Tommaso Cucinotta <tommaso.cucinotta@santannapisa.it>
Subject: Re: [RFC 2/3] preempt_tracer: Disable IRQ while starting/stopping
 due to a preempt_counter change
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On Wed, 29 May 2019 15:49:46 +0200
Peter Zijlstra <peterz@infradead.org> wrote:


> > That's basically what I was suggesting as the solution to this ;-)  
> 
> You were wanting changes to preempt_disable() and task_struct, neither
> of which is required. The above only needs some per-cpu storage in the
> tracer implementation.

Only changes were to the trace preempt_disable() code. Which I still
think needs to be done regardless to differentiate between when we are
tracing preempt disable and when we are not.

And no modification would need to be done to task_struct as we already
have a place to add tracing flags.

-- Steve