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From: Ingo Molnar <mingo@elte.hu>
To: George Anzinger <george@mvista.com>
Cc: Thomas Gleixner <tglx@linutronix.de>,
	LKML <linux-kernel@vger.kernel.org>,
	Doug Niehaus <niehaus@ittc.ku.edu>,
	Benedikt Spranger <bene@linutronix.de>
Subject: Re: High resolution timers and BH processing on -RT
Date: Fri, 28 Jan 2005 19:51:01 +0100	[thread overview]
Message-ID: <20050128185101.GC25164@elte.hu> (raw)
In-Reply-To: <41FA85A7.4000805@mvista.com>


* George Anzinger <george@mvista.com> wrote:

> A quick comment here on the current RT code.  It looks to me like
> there is a race in timer delivery.  It looks like the softirq is
> "raised" by the PIT interrupt code and the jiffie is bumped by the
> timer thread.  If the softirq gets to run prior to the PIT interrupt
> thread we could end up in the run_timer list code with a stale jiffie
> value and do nothing.  This would delay normal timers for a jiffie and
> HRT timers for some time less than a jiffie, depending on when they
> were really due.
> 
> I thing we should move the raising of the timer softirq to the PIT
> interrupt thread after we release the xtime_lock.

ok - mind sending a patch for this?

	Ingo

  reply	other threads:[~2005-01-28 18:51 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-01-28  0:13 High resolution timers and BH processing on -RT Thomas Gleixner
2005-01-28  4:43 ` Ingo Molnar
2005-01-28  8:20   ` Thomas Gleixner
2005-01-28  8:24     ` Ingo Molnar
2005-01-28  8:30       ` Thomas Gleixner
2005-01-28  8:47         ` Ingo Molnar
2005-01-28 18:34           ` George Anzinger
2005-01-28 18:51             ` Ingo Molnar [this message]
2005-01-28 18:53             ` Ingo Molnar
2005-01-31  9:12             ` Thomas Gleixner

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