From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dan Williams <dan.j.williams@intel.com>
Subject: Re: [PATCH v2 3/3] libata: use blk taging
Date: Thu, 15 Jan 2015 11:51:37 -0800
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To: Jens Axboe <axboe@fb.com>
Cc: Shaohua Li <shli@fb.com>, Christoph Hellwig <hch@infradead.org>, Tejun Heo <tj@kernel.org>, IDE/ATA development list <linux-ide@vger.kernel.org>, Kernel-team@fb.com

On Thu, Jan 15, 2015 at 11:15 AM, Jens Axboe <axboe@fb.com> wrote:
> On 01/15/2015 11:59 AM, Dan Williams wrote:
>> I still don't understand what we get by adding this new allocator
>> besides complexity, am I missing something?
>
>
> Two things:
>
> - libata tag allocator sucks. Like seriously sucks, it's almost a worst case
> implementation.

Not questioning its suckiness, but I thought the SATA suckiness made
it moot.  Apparently not in all cases...

> - Much better to have a single unified allocator to tweak and tune, than
> having separate version.
>
> #2 is still lacking a bit, but I don't think it'd be impossible to unify it
> all.

https://bugzilla.kernel.org/show_bug.cgi?id=87101 has gone silent, I
need to ping it.  That's my primary concern with the current proposal,
supporting controllers that have weird/unnatural relationships  with
the value of the tag.