Re: init_timer_deferrable conversion

From: Stephen Hemminger
Date: Mon Dec 17 2007 - 12:01:47 EST


On Mon, 17 Dec 2007 15:29:43 +0100
Eric Dumazet <dada1@xxxxxxxxxxxxx> wrote:

> On Mon, 17 Dec 2007 09:55:04 +0100
> Eric Dumazet <dada1@xxxxxxxxxxxxx> wrote:
>
> > On Sun, 16 Dec 2007 22:00:23 -0500 (EST)
> > Parag Warudkar <parag.warudkar@xxxxxxxxx> wrote:
> >
> > > In my quest to get the wake-ups from idle per second down to bare minimum,
> > > I noticed 3 places in the kernel that could benefit from
> > > using init_timer_deferrable() instead of init_timer() -
> > >
> > > a) drivers/net/sky2.c - watchdog_timer. This was showing up high on
> > > Powertop's list of things that cause routine wakeups from idle. After
> > > converting to init_timer_deferrable() the wakeups went down and this one
> > > no longer shows up in powertop's list. 25% reduction.

This surprises me because it is a 1 hz timer and uses round_jiffies() in
the current kernel.



--
Stephen Hemminger <shemminger@xxxxxxxxxxxxxxxxxxxx>
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