From: Jeremy Fitzhardinge <jeremy@goop.org>
Subject: Re: [PATCH] Allow lazy unmapping by taking extra page references
 V3
Date: Wed, 24 Oct 2007 15:46:16 -0700
Message-ID: <471FCB38.10106@goop.org>
References: <p73sl439s7k.fsf@bingen.suse.de> <471CEEB4.9040807@goop.org> <20071022190740.GA1695@one.firstfloor.org> <20071022223224.GC995458@sgi.com> <20071022233514.GA9057@one.firstfloor.org> <20071023003641.GF995458@sgi.com> <20071023070414.GM66820511@sgi.com> <20071023093035.GB24536@one.firstfloor.org> <20071024043619.GE66820511@sgi.com> <471ED35F.3020605@goop.org> <20071024214826.GH66820511@sgi.com>
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To: David Chinner <dgc@sgi.com>
Cc: Andi Kleen <andi@firstfloor.org>, dean gaudet <dean@arctic.org>, Nick Piggin <nickpiggin@yahoo.com.au>, Xen-devel <xen-devel@lists.xensource.com>, Morten@suse.de, Linux Kernel Mailing List <linux-kernel@vger.kernel.org>, =?ISO-8859-1?Q?B=F8geskov?= <xen-users@morten.bogeskov.dk>, xfs@oss.sgi.com, xfs-masters@oss.sgi.com, Mark Williamson <mark.williamson@cl.cam.ac.uk>
List-Id: xen-devel@lists.xenproject.org

David Chinner wrote:
> Allow lazy unmapping of vmap()d regions be taking a reference
> on each page in the region being vmap()ed. The page references
> get released after the region is vunmap()ed, thereby ensuring
> we don't leave stray mappings on freed pages that could lead to
> problems pages being reallocated with incorrect mappings
> associated with them.
>
> Tested with XFS filesystems with 64k directory blocks with
> dirstress and XFSQA.
>
> Version 3:
>   - compile on latest -git
>   

Not quite:

  CC      mm/vmalloc.o
/home/jeremy/hg/xen/paravirt/linux/mm/vmalloc.c: In function 'vm_area_alloc_pagearray':
/home/jeremy/hg/xen/paravirt/linux/mm/vmalloc.c:338: error: 'GFP_LEVEL_MASK' undeclared (first use in this function)
/home/jeremy/hg/xen/paravirt/linux/mm/vmalloc.c:338: error: (Each undeclared identifier is reported only once
/home/jeremy/hg/xen/paravirt/linux/mm/vmalloc.c:338: error: for each function it appears in.)
make[3]: *** [mm/vmalloc.o] Error 1
make[2]: *** [mm] Error 2
make[2]: *** Waiting for unfinished jobs....


GFP_RECLAM_MASK now?

J