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Date: Wed, 12 Mar 2014 07:49:02 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>, Jiri Bohac <jbohac@suse.cz>,
        linux-kernel@vger.kernel.org
Subject: Re: is printk() safe within a timekeeper_seq write section?
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References: <20140306174531.GA30634@midget.suse.cz>
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On Tue, Mar 11, 2014 at 02:54:13PM -0700, John Stultz wrote:
> Ok, so a generic solution is probably not going to be worth it then. My
> thought was that since we do a very limited amount of informational
> printks in the timekeeping code, we can be fairly safe delaying the
> print-out until we drop the locks.
> 
> For timekeeping, its really 4 call sites:
> * invalid inject_sleep_time deltas
> * > 11% clocksource freq adjustments
> * insert leap second
> * delete leap second
> 

There is the printk_sched() you can reuse; you might want to change the
name and the generic [sched_delayed] prefix it gets though.