Subject: Re: [PATCH V3 4/5] mm: mmap: Add mmap flag to request VM_LOCKONFAULT

From: Chris Metcalf <[email-masked]>
Date: Mon, 20 Jul 2015 16:40:25 -0400

On 07/18/2015 03:11 PM, Paul Gortmaker wrote:
> On Tue, Jul 7, 2015 at 1:03 PM, Eric B Munson<[email-masked]>  wrote:
>> >The cost of faulting in all memory to be locked can be very high when
>> >working with large mappings.  If only portions of the mapping will be
>> >used this can incur a high penalty for locking.
>> >
>> >Now that we have the new VMA flag for the locked but not present state,
>> >expose it  as an mmap option like MAP_LOCKED -> VM_LOCKED.
> An automatic bisection on arch/tile leads to this commit:
>
> 5a5656f2c9b61c74c15f9ef3fa2e6513b6c237bb is the first bad commit
> commit 5a5656f2c9b61c74c15f9ef3fa2e6513b6c237bb
> Author: Eric B Munson<[email-masked]>
> Date:   Thu Jul 16 10:09:22 2015 +1000
>
>      mm: mmap: add mmap flag to request VM_LOCKONFAULT

Eric, I'm happy to help with figuring out the tile issues.

-- 
Chris Metcalf, EZChip Semiconductor
http://www.ezchip.com