Re: [PATCH 3/3] nvme-core: mark internal passthru req REQ_QUIET

Keith Busch
2022-04-13T17:09:49Z

On Wed, Apr 13, 2022 at 10:57:19AM -0600, Jonathan Derrick wrote:
>
>
> On 4/13/2022 10:52 AM, Christoph Hellwig wrote:
> > On Wed, Apr 13, 2022 at 10:49:33AM -0600, Jonathan Derrick wrote:
> > > > + req->rq_flags |= RQF_QUIET;
> > > Any reason to not make it a part of flags in the argument list and let the
> > > block layer build the req with it?
> > >
> > > eg:
> > > flags |= REQ_QUIET;
> >
> > Because there is not REQ_QUIET, just RQF_QUIET and BIO_QUIET, and their
> > relation isn't quite as straightforward as it seems.
>
> Well let's suppose I had written RQF_QUIET instead of the non-existent
> REQ_QUIET

The "flags" value passed to blk_mq_alloc_request() is not the same as the
values for rq_flags, though.

I guess you could add a new allocation flag, maybe called something like
BLK_MQ_REQ_QUIET to tell the block layer to set RQF_QUIET. That is similiar to
how BLK_MQ_REQ_PM is used for RQF_PM, but I'm not sure we want to add another
'if' check in the fast path.