From: Jeff Moyer <jmoyer-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
Subject: Re: [PATCH 00/42] v7: separate operations from flags in
	the bio/request structs
Date: Tue, 03 May 2016 16:44:02 -0400
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	(mchristi-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org's message of "Fri, 15 Apr 2016 14:15:35 -0500")
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mchristi-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org writes:

> The following patches begin to cleanup the request->cmd_flags and
> bio->bi_rw mess. We currently use cmd_flags to specify the operation,
> attributes and state of the request. For bi_rw we use it for similar
> info and also the priority but then also have another bi_flags field
> for state. At some point, we abused them so much we just made cmd_flags
> 64 bits, so we could add more.
>
> The following patches seperate the operation (read, write discard,
> flush, etc) from cmd_flags/bi_rw.
>
> This patchset was made against linux-next from today April 15
> (git tag next-20160415).
>
> I put a git tree here:
> https://github.com/mikechristie/linux-kernel.git
> The patches are in the op branch.

Hi, Mike,

That git tree doesn't seem to exist.  I did manage to apply your patch
set on top of next-20160415, though.

So... what testing did you do? ;-) I ran into the following problems:
- git clone fails
- yum segfaults
- many blktrace/blkparse issues, including incorrect cpu recorded in
  traces, null task names, and blkparse outputting nothing for a trace
  file several gigabytes in size.

After that, I decided to back out your patches and test the base
linux-next kernel.  That kernel has none of those issues.

So, either I'm missing some dependencies, or I think we've got some
issues to iron out before this thing goes in.  Before I dig any further,
am I missing something?

Cheers,
Jeff