Re: [PATCH 00/42] v7: separate operations from flags in the bio/request structs

From: Jeff Moyer
Date: Tue May 03 2016 - 16:44:16 EST


mchristi@xxxxxxxxxx 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