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Subject: [RFC] IPV4 long lasting timer function
From: Thomas Gleixner <tglx@linutronix.de>
Reply-To: tglx@linutronix.de
To: "David S. Miller" <davem@davemloft.net>
Cc: Ingo Molnar <mingo@elte.hu>, LKML <linux-kernel@vger.kernel.org>
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Organization: linutronix
Date: Wed, 17 Aug 2005 22:59:01 +0200
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Hi,

while tracking down some timer related ugliness I stumbled over the
timer driven function rt_secret_rebuild(), which does a loop over
rt_has_mask (1024 in my case) entries and possibly some subsequent
variable sized loops inside each step.

On a 300MHZ PPC system this accumulated to a worst case total of >5ms. I
could not reproduce it with this magnitude, but applying heavy
networking load is definitely triggering this behaviour.

Shouldn't this be converted to a workqueue, which gets triggered by a
timer instead of blocking the timer softirq and therefor the delivery of
other timer functions that long ?

tglx