Re: [PATCH] sunrpc: make the cache cleaner workqueue deferrable

["J. Bruce Fields" <bfields@fieldses.org>]

On Mon, Jul 05, 2010 at 03:31:30PM +0300, Artem Bityutskiy wrote:
> On Thu, 2010-07-01 at 18:05 +0300, Artem Bityutskiy wrote:
> > From: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
> > 
> > This patch makes the cache_cleaner workqueue deferrable, to prevent
> > unnecessary system wake-ups, which is very important for embedded
> > battery-powered devices.
> > 
> > do_cache_clean() is called every 30 seconds at the moment, and often
> > makes the system wake up from its power-save sleep state. With this
> > change, when the workqueue uses a deferrable timer, the
> > do_cache_clean() invocation will be delayed and combined with the
> > closest "real" wake-up. This improves the power consumption situation.
> > 
> > Note, I tried to create a DECLARE_DELAYED_WORK_DEFERRABLE() helper
> > macro, similar to DECLARE_DELAYED_WORK(), but failed because of the
> > way the timer wheel core stores the deferrable flag (it is the
> > LSBit in the time->base pointer). My attempt to define a static
> > variable with this bit set ended up with the "initializer element is
> > not constant" error.
> > 
> > Thus, I have to use run-time initialization, so I created a new
> > cache_initialize() function which is called once when sunrpc is
> > being initialized.
> > 
> > Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
> 
> Bruce,
> 
> I did some git-logging, and found out that sunrpc stuff goes from you,
> from Trond, and from David, and MAINTAINERS also mentions Neil. Whom
> should I ping WRT to merging this patch?

I got it.  (I'm just getting back from vacation, and very backlogged.)

--b.