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From:   Logan Gunthorpe <logang@deltatee.com>
Message-ID: <5f79c012-c6e1-56bb-62fd-0689181fb2c9@deltatee.com>
Date:   Mon, 3 Sep 2018 16:26:27 -0600
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Subject: Re: [PATCH v5 07/13] block: Add PCI P2P flag for request queue and
 check support for requests
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On 01/09/18 02:28 AM, Christoph Hellwig wrote:
> On Thu, Aug 30, 2018 at 01:11:18PM -0600, Jens Axboe wrote:
>> I think this belongs in the caller - both the validity check, and
>> passing in NOMERGE for this type of request. I don't want to impose
>> this overhead on everything, for a pretty niche case.
> 
> It is just a single branch, which will be predicted as not taken
> for non-P2P users.  The benefit is that we get proper error checking
> by doing it in the block code.

I personally agree with Christoph. But if there's consensus in the other
direction or this is a real blocker moving this forward, I can remove it
for the next version.

Logan