Re: PROBLEM: CONFIG_NO_HZ could cause software timeouts

From: Pavel Machek
Date: Sun Sep 06 2009 - 01:27:31 EST

On Thu 2009-09-03 12:50:12, Norbert van Bolhuis wrote:
> The problem occurs when e.g. drivers use time_after(jiffes, timeout).
> CONFIG_NO_HZ could make jiffies advance by more than 1.
> This is done by: tick_nohz_update_jiffies->tick_do_update_jiffies64->do_timer

jiffies really should be up-to-date as long as you are running
anything else than idle loop. If not, that's a bug ... and nasty one.

(cesky, pictures)
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