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Date:   Mon, 28 Sep 2020 17:33:31 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     quanyang.wang@windriver.com, linux-kernel@vger.kernel.org,
        Thomas Gleixner <tglx@linutronix.de>,
        Leo Yan <leo.yan@linaro.org>, Will Deacon <will@kernel.org>,
        a.darwish@linutronix.de,
        Daniel Lezcano <daniel.lezcano@linaro.org>,
        Paul Cercueil <paul@crapouillou.net>,
        Randy Dunlap <rdunlap@infradead.org>, ben.dooks@codethink.co.uk
Subject: Re: [PATCH] time/sched_clock: mark sched_clock_read_begin as
 notrace
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On Mon, 28 Sep 2020 12:58:59 +0200
Peter Zijlstra <peterz@infradead.org> wrote:

> > -struct clock_read_data *sched_clock_read_begin(unsigned int *seq)
> > +notrace struct clock_read_data *sched_clock_read_begin(unsigned int *seq)
> >  {
> >  	*seq = raw_read_seqcount_latch(&cd.seq);
> >  	return cd.read_data + (*seq & 1);  
> 
> At the very least sched_clock_read_retry() should also be marked such.
> 
> But Steve, how come x86 works? Our sched_clock() doesn't have notrace on
> at all.

It's because of that magic in the Makefile that you love so much ;-)

CFLAGS_REMOVE_tsc.o = -pg

-- Steve