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Date: Thu, 13 Apr 2006 17:42:32 -0700
From: Andrew Morton <akpm@osdl.org>
To: Christoph Lameter <clameter@sgi.com>
Cc: hugh@veritas.com, linux-kernel@vger.kernel.org, lee.schermerhorn@hp.com,
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Subject: Re: [PATCH 2/5] Swapless V2: Add migration swap entries
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Christoph Lameter <clameter@sgi.com> wrote:
>
> On Thu, 13 Apr 2006, Andrew Morton wrote:
> 
> > Christoph Lameter <clameter@sgi.com> wrote:
> > >
> > > +
> > >  +	if (unlikely(is_migration_entry(entry))) {
> > 
> > Perhaps put the unlikely() in is_migration_entry()?
> > 
> > >  +		yield();
> > 
> > Please, no yielding.
> > 
> > _especially_ no unchangelogged, uncommented yielding.
> 
> Page migration is ongoing so its best to do something else first.

That doesn't help a lot.  What is "something else"?  What are the dynamics
in there, and why do you feel that some sort of delay is needed?

> Add a comment?

I don't think we're up to that stage yet.