Re: [PATCH] nfs: fix congestion control -v4

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Thu, 2007-01-25 at 21:02 -0800, Andrew Morton wrote:
> On Thu, 25 Jan 2007 16:32:28 +0100
> Peter Zijlstra <[email protected]> wrote:
> 
> > +long congestion_wait_interruptible(int rw, long timeout)
> > +{
> > +	long ret;
> > +	DEFINE_WAIT(wait);
> > +	wait_queue_head_t *wqh = &congestion_wqh[rw];
> > +
> > +	prepare_to_wait(wqh, &wait, TASK_INTERRUPTIBLE);
> > +	if (signal_pending(current))
> > +		ret = -ERESTARTSYS;
> > +	else
> > +		ret = io_schedule_timeout(timeout);
> > +	finish_wait(wqh, &wait);
> > +	return ret;
> > +}
> > +EXPORT_SYMBOL(congestion_wait_interruptible);
> 
> I think this can share code with congestion_wait()?
> 
> static long __congestion_wait(int rw, long timeout, int state)
> {
> 	long ret;
> 	DEFINE_WAIT(wait);
> 	wait_queue_head_t *wqh = &congestion_wqh[rw];
> 
> 	prepare_to_wait(wqh, &wait, state);
> 	ret = io_schedule_timeout(timeout);
> 	finish_wait(wqh, &wait);
> 	return ret;
> }
> 
> long congestion_wait_interruptible(int rw, long timeout)
> {
> 	long ret = __congestion_wait(rw, timeout);
> 
> 	if (signal_pending(current))
> 		ret = -ERESTARTSYS;
> 	return ret;
> }
> 
> it's only infinitesimally less efficient..

All the other _interruptible functions check signal_pending before
calling schedule. Which seems to make sense since its called in a loop
anyway, and if the loop condition turns false when interrupted you might
as well just finish up instead of bailing out.

However if you'd rather see your version, who am I to object ;-)

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux