Subject: Re: uvm_vnp_setsize
To: YAMAMOTO Takashi <yamt@mwd.biglobe.ne.jp>
From: Chuck Silvers <chuq@chuq.com>
List: tech-kern
Date: 07/07/2006 08:38:34
On Fri, Jul 07, 2006 at 11:21:40AM +0900, YAMAMOTO Takashi wrote:
> > that looks fine, though it would probably be useful if we tried to get
> > the glock in the PGO_LOCKED case too.  this would allow us to hold the
> > glock in exclusive mode to prevent other threads from gaining access to
> > existing pages as well as to prevent the creation of new pages.
> 
> why do you want to prevent other threads from gaining access?

I was thinking it would be useful for the pager to be able to prevent
other threads from making the pages dirty.  that would allow us to do
things like rearrange the bmap without worrying about the pagedaemon
wanting to flush the pages to disk.  it seems likely there will be
other cases where this facility will be useful too.

-Chuck