From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Bart Van Assche To: "hch@lst.de" , "axboe@kernel.dk" CC: "osandov@fb.com" , "linux-block@vger.kernel.org" , "hare@suse.com" Subject: Re: [PATCH v2 12/12] block: Rename blk_mq_rq_{to,from}_pdu() Date: Thu, 1 Jun 2017 19:17:03 +0000 Message-ID: <1496344622.3075.10.camel@sandisk.com> References: <20170531225246.26261-1-bart.vanassche@sandisk.com> <20170531225246.26261-13-bart.vanassche@sandisk.com> <20170601060804.GE16248@lst.de> <1496322662.2787.1.camel@sandisk.com> <4ffd4d62-0e2d-0eb9-aa9a-0550363259d4@kernel.dk> In-Reply-To: <4ffd4d62-0e2d-0eb9-aa9a-0550363259d4@kernel.dk> Content-Type: text/plain; charset="iso-8859-1" MIME-Version: 1.0 List-ID: On Thu, 2017-06-01 at 12:06 -0700, Jens Axboe wrote: > On 06/01/2017 06:11 AM, Bart Van Assche wrote: > > On Thu, 2017-06-01 at 08:08 +0200, Christoph Hellwig wrote: > > > On Wed, May 31, 2017 at 03:52:46PM -0700, Bart Van Assche wrote: > > > > Commit 6d247d7f71d1 ("block: allow specifying size for extra comman= d > > > > data") added support for .cmd_size to blk-sq. Due to that patch the > > > > blk_mq_rq_{to,from}_pdu() functions are also useful for single-queu= e > > > > block drivers. Hence remove "_mq" from the name of these functions. > > > > This patch does not change any functionality. Most of this patch ha= s > > > > been generated by running the following shell command: > > >=20 > > > I don't really see the point of this as it's primarily a blk-mq API > > > and we still hope to get rid of the old code. But I'm not necessaril= y > > > against it either. > >=20 > > I would like to introduce calls to these functions in several scsi-sq > > functions. If I would do that without renaming these functions then any= one > > who reads the code of these functions and sees calls to functions with = a > > blk_mq_ prefix could get really confused when trying to figure out whet= her > > these functions are used by scsi-sq, scsi-mq or perhaps both. >=20 > But that should go away, eventually. Hello Jens, I agree that we should work towards removal of the single queue block layer= . But how long will it take before that code is removed? Due to recent patches from Christoph the 'request' member in struct scsi_cm= nd is now superfluous. I'd like to replace accesses to that member by a call t= o blk_mq_rq_from_pdu(). I'm afraid that doing that in scsi-sq code paths will make that code look weird. Bart.=