From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Vrabel <david.vrabel@citrix.com>
Subject: Re: [PATCH] gnttab: lock the left grant table earlier
 in	__gnttab_unmap_common()
Date: Mon, 11 Nov 2013 10:53:23 +0000
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To: Matt Wilson <msw@linux.com>
Cc: Keir Fraser <keir@xen.org>, Matt Wilson <msw@amazon.com>, Andrew Cooper <andrew.cooper3@citrix.com>, Jan Beulich <jbeulich@suse.com>, Anthony Liguori <aliguori@amazon.com>, xen-devel@lists.xenproject.org
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On 11/11/13 02:07, Matt Wilson wrote:
> From: Matt Wilson <msw@amazon.com>
> 
> Luckily today maptrack_limit never shrinks. But if at some point in
> the future this were to change, checking maptrack_limit without
> holding the grant table spinlock would no longer be safe.

I don't think we should extend region the grant table lock protects if
it's not needed since we know this lock is heavily contended.

Also, doesn't the 'l' and 'r' prefixes mean 'local' and 'remote' not
'left' and 'right'?

David