From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
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Date: Thu, 3 Aug 2006 19:26:19 +0200
Subject: Re: [Xenomai-core] [RFC][PATCH 4/4] shorten overrun loops of periodic
	timers
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To: Jan Kiszka <jan.kiszka@domain.hid>
Cc: xenomai-core <xenomai@xenomai.org>

Jan Kiszka wrote:
 > A simple patch, just like suggested by Gilles, to avoid looping over
 > periodic xntimer handlers in case of overruns.
 > 
 > It saves the current TSC on loop entry and uses this value later when
 > forwarding the timer. Is is the overhead of re-reading the TSC on all
 > archs negligible and should we rather go that way?

 >(...)
 > -				xntimerh_date(&timer->aplink) +=
 > -				    nkpod->htimer.interval;
 > +				while ((xntimerh_date(&timer->aplink) +=
 > +				        nkpod->htimer.interval) < now);

I think you are patching the wrong addition, the one you are interested
in is most probably the one at the bottom of xntimer_do_tick_aperiodic.

-- 


					    Gilles Chanteperdrix.