From: "hch@lst.de" <hch@lst.de> To: Bart Van Assche <Bart.VanAssche@sandisk.com> Cc: "linux-raid@vger.kernel.org" <linux-raid@vger.kernel.org>, "snitzer@redhat.com" <snitzer@redhat.com>, "linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>, "axboe@fb.com" <axboe@fb.com>, "dm-devel@redhat.com" <dm-devel@redhat.com>, "linux-block@vger.kernel.org" <linux-block@vger.kernel.org>, "j-nomura@ce.jp.nec.com" <j-nomura@ce.jp.nec.com>, "hch@lst.de" <hch@lst.de> Subject: Re: [PATCH 15/18] scsi: allocate scsi_cmnd structures as part of struct request Date: Sat, 28 Jan 2017 09:25:13 +0100 [thread overview] Message-ID: <20170128082513.GB4728@lst.de> (raw) In-Reply-To: <1485542367.4267.19.camel@sandisk.com> On Fri, Jan 27, 2017 at 06:39:46PM +0000, Bart Van Assche wrote: > Why have the scsi_release_buffers() and scsi_put_command(cmd) calls been > moved up? I haven't found an explanation for this change in the patch > description. Because they reference the scsi_cmnd, which are now part of the request and thus freed by blk_finish_request. And yes, I should have mentioned it in the changelog, sorry. > Please also consider to remove the cmd->request->special = NULL assignments > via this patch. Since this patch makes the lifetime of struct scsi_cmnd and > struct request identical these assignments are no longer needed. True. If I had to resend again I would have fixed it up, but it's probably not worth the churn now. > This patch introduces the function scsi_exit_rq(). Having two functions > for the single-queue path that release resources (scsi_release_buffers() > and scsi_exit_rq()) is confusing. Since every scsi_release_buffers() call > is followed by a blk_unprep_request() call, have you considered to move > the scsi_release_buffers() call into scsi_unprep_fn() via an additional > patch? We could have done that. But it's just more change for a code path that I hope won't survive this calendar year.
WARNING: multiple messages have this Message-ID (diff)
From: "hch@lst.de" <hch@lst.de> To: Bart Van Assche <Bart.VanAssche@sandisk.com> Cc: "hch@lst.de" <hch@lst.de>, "axboe@fb.com" <axboe@fb.com>, "linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>, "linux-raid@vger.kernel.org" <linux-raid@vger.kernel.org>, "dm-devel@redhat.com" <dm-devel@redhat.com>, "linux-block@vger.kernel.org" <linux-block@vger.kernel.org>, "snitzer@redhat.com" <snitzer@redhat.com>, "j-nomura@ce.jp.nec.com" <j-nomura@ce.jp.nec.com> Subject: Re: [PATCH 15/18] scsi: allocate scsi_cmnd structures as part of struct request Date: Sat, 28 Jan 2017 09:25:13 +0100 [thread overview] Message-ID: <20170128082513.GB4728@lst.de> (raw) In-Reply-To: <1485542367.4267.19.camel@sandisk.com> On Fri, Jan 27, 2017 at 06:39:46PM +0000, Bart Van Assche wrote: > Why�have the�scsi_release_buffers() and scsi_put_command(cmd) calls been > moved up? I haven't found an explanation for this change in the patch > description. Because they reference the scsi_cmnd, which are now part of the request and thus freed by blk_finish_request. And yes, I should have mentioned it in the changelog, sorry. > Please also consider to remove the cmd->request->special = NULL assignments > via this patch. Since this patch makes the lifetime of struct scsi_cmnd and > struct request identical these assignments are no longer needed. True. If I had to resend again I would have fixed it up, but it's probably not worth the churn now. > This patch introduces the function scsi_exit_rq(). Having two functions > for the single-queue path that release resources (scsi_release_buffers() > and scsi_exit_rq()) is confusing. Since every scsi_release_buffers() call > is followed by a blk_unprep_request() call, have you considered to move > the scsi_release_buffers() call into scsi_unprep_fn() via an additional > patch? We could have done that. But it's just more change for a code path that I hope won't survive this calendar year.
next prev parent reply other threads:[~2017-01-28 8:25 UTC|newest] Thread overview: 172+ messages / expand[flat|nested] mbox.gz Atom feed top 2017-01-25 17:25 split scsi passthrough fields out of struct request V2 Christoph Hellwig 2017-01-25 17:25 ` [PATCH 01/18] block: add a op_is_flush helper Christoph Hellwig 2017-01-26 2:58 ` Martin K. Petersen 2017-01-26 22:38 ` Bart Van Assche 2017-01-25 17:25 ` [PATCH 02/18] md: cleanup bio op / flags handling in raid1_write_request Christoph Hellwig 2017-01-26 2:59 ` Martin K. Petersen 2017-01-26 23:18 ` Bart Van Assche 2017-01-26 23:18 ` Bart Van Assche 2017-01-25 17:25 ` [PATCH 03/18] block: fix elevator init check Christoph Hellwig 2017-01-26 3:01 ` Martin K. Petersen 2017-01-26 23:21 ` Bart Van Assche 2017-01-26 23:21 ` Bart Van Assche 2017-01-25 17:25 ` [PATCH 04/18] block: simplify blk_init_allocated_queue Christoph Hellwig 2017-01-26 3:02 ` Martin K. Petersen 2017-01-26 23:27 ` Bart Van Assche 2017-01-26 23:27 ` Bart Van Assche 2017-01-25 17:25 ` [PATCH 05/18] block: allow specifying size for extra command data Christoph Hellwig 2017-01-26 3:15 ` Martin K. Petersen 2017-01-27 16:12 ` Christoph Hellwig 2017-01-27 16:12 ` Christoph Hellwig 2017-01-27 17:21 ` Bart Van Assche 2017-01-27 17:21 ` Bart Van Assche 2017-01-27 17:26 ` Jens Axboe 2017-01-27 17:26 ` Jens Axboe 2017-01-27 17:30 ` Bart Van Assche 2017-01-27 17:30 ` Bart Van Assche 2017-01-27 17:33 ` Jens Axboe 2017-01-25 17:25 ` [PATCH 06/18] dm: remove incomple BLOCK_PC support Christoph Hellwig 2017-01-27 17:32 ` Bart Van Assche 2017-01-27 17:32 ` Bart Van Assche 2017-01-25 17:25 ` [PATCH 07/18] dm: always defer request allocation to the owner of the request_queue Christoph Hellwig 2017-01-27 16:34 ` Mike Snitzer 2017-01-27 16:34 ` Mike Snitzer 2017-01-27 16:36 ` Christoph Hellwig 2017-01-27 16:36 ` Christoph Hellwig 2017-01-27 16:44 ` Mike Snitzer 2017-01-27 16:44 ` Mike Snitzer 2017-01-25 17:25 ` [PATCH 08/18] scsi_dh_rdac: switch to scsi_execute_req_flags() Christoph Hellwig 2017-01-26 3:18 ` Martin K. Petersen 2017-01-25 17:25 ` [PATCH 09/18] scsi_dh_emc: " Christoph Hellwig 2017-01-26 3:19 ` Martin K. Petersen 2017-01-25 17:25 ` [PATCH 10/18] scsi_dh_hp_sw: " Christoph Hellwig 2017-01-26 3:20 ` Martin K. Petersen 2017-01-26 3:20 ` Martin K. Petersen 2017-01-25 17:25 ` [PATCH 11/18] scsi: remove gfp_flags member in scsi_host_cmd_pool Christoph Hellwig 2017-01-26 3:21 ` Martin K. Petersen 2017-01-27 17:38 ` Bart Van Assche 2017-01-27 17:38 ` Bart Van Assche 2017-01-25 17:25 ` [PATCH 12/18] scsi: respect unchecked_isa_dma for blk-mq Christoph Hellwig 2017-01-26 3:23 ` Martin K. Petersen 2017-01-27 17:45 ` Bart Van Assche 2017-01-27 17:45 ` Bart Van Assche 2017-01-25 17:25 ` [PATCH 13/18] scsi: remove scsi_cmd_dma_pool Christoph Hellwig 2017-01-26 3:24 ` Martin K. Petersen 2017-01-27 17:51 ` Bart Van Assche 2017-01-27 17:51 ` Bart Van Assche 2017-01-25 17:25 ` [PATCH 14/18] scsi: remove __scsi_alloc_queue Christoph Hellwig 2017-01-26 3:25 ` Martin K. Petersen 2017-01-27 17:58 ` Bart Van Assche 2017-01-27 17:58 ` Bart Van Assche 2017-01-28 8:23 ` hch 2017-01-25 17:25 ` [PATCH 15/18] scsi: allocate scsi_cmnd structures as part of struct request Christoph Hellwig 2017-01-26 3:30 ` Martin K. Petersen 2017-01-27 18:39 ` Bart Van Assche 2017-01-27 18:39 ` Bart Van Assche 2017-01-28 8:25 ` hch [this message] 2017-01-28 8:25 ` hch 2017-01-25 17:25 ` [PATCH 16/18] block/bsg: move queue creation into bsg_setup_queue Christoph Hellwig 2017-01-27 18:48 ` Bart Van Assche 2017-01-27 18:48 ` Bart Van Assche 2017-01-25 17:25 ` [PATCH 17/18] block: split scsi_request out of struct request Christoph Hellwig 2017-01-25 17:25 ` [PATCH 18/18] block: don't assign cmd_flags in __blk_rq_prep_clone Christoph Hellwig 2017-01-26 3:31 ` Martin K. Petersen 2017-01-26 18:29 ` split scsi passthrough fields out of struct request V2 Bart Van Assche 2017-01-26 18:29 ` Bart Van Assche 2017-01-26 18:44 ` Jens Axboe 2017-01-26 18:52 ` Bart Van Assche 2017-01-26 18:52 ` Bart Van Assche 2017-01-26 18:57 ` Jens Axboe 2017-01-26 18:59 ` hch 2017-01-26 19:01 ` Jens Axboe 2017-01-26 19:01 ` Jens Axboe 2017-01-26 20:47 ` [dm-devel] " Bart Van Assche 2017-01-26 20:54 ` Jens Axboe 2017-01-26 20:54 ` [dm-devel] " Jens Axboe 2017-01-26 21:01 ` Bart Van Assche 2017-01-26 21:01 ` Bart Van Assche 2017-01-26 21:12 ` Jens Axboe 2017-01-26 21:12 ` [dm-devel] " Jens Axboe 2017-01-26 21:47 ` Bart Van Assche 2017-01-26 21:47 ` [dm-devel] " Bart Van Assche 2017-01-26 21:51 ` Jens Axboe 2017-01-26 21:51 ` [dm-devel] " Jens Axboe 2017-01-26 23:14 ` Bart Van Assche 2017-01-26 23:14 ` Bart Van Assche 2017-01-26 23:26 ` Jens Axboe 2017-01-26 23:26 ` Jens Axboe 2017-01-26 23:26 ` [dm-devel] " Jens Axboe 2017-01-26 23:47 ` Bart Van Assche 2017-01-26 23:47 ` [dm-devel] " Bart Van Assche 2017-01-26 23:50 ` Jens Axboe 2017-01-27 0:33 ` Jens Axboe 2017-01-27 0:33 ` [dm-devel] " Jens Axboe 2017-01-27 0:38 ` Bart Van Assche 2017-01-27 0:38 ` Bart Van Assche 2017-01-27 0:41 ` Jens Axboe 2017-01-27 1:15 ` Bart Van Assche 2017-01-27 1:15 ` [dm-devel] " Bart Van Assche 2017-01-27 1:22 ` Jens Axboe 2017-01-27 1:22 ` [dm-devel] " Jens Axboe 2017-01-27 6:40 ` Jens Axboe 2017-01-27 8:04 ` Jens Axboe 2017-01-27 8:04 ` [dm-devel] " Jens Axboe 2017-01-27 16:52 ` Bart Van Assche 2017-01-27 16:52 ` [dm-devel] " Bart Van Assche 2017-01-27 16:56 ` Jens Axboe 2017-01-27 16:56 ` [dm-devel] " Jens Axboe 2017-01-27 17:03 ` Bart Van Assche 2017-01-27 17:03 ` [dm-devel] " Bart Van Assche 2017-01-31 1:12 ` Bart Van Assche 2017-01-31 1:12 ` Bart Van Assche 2017-01-31 1:38 ` Jens Axboe 2017-01-31 1:38 ` Jens Axboe 2017-01-31 4:13 ` Jens Axboe 2017-01-31 4:13 ` [dm-devel] " Jens Axboe 2017-01-31 21:35 ` Bart Van Assche 2017-01-31 21:35 ` Bart Van Assche 2017-01-31 21:55 ` Bart Van Assche 2017-01-31 21:55 ` Bart Van Assche 2017-01-31 21:58 ` Jens Axboe 2017-02-01 1:01 ` Bart Van Assche 2017-02-01 6:38 ` Jens Axboe 2017-02-01 16:46 ` Bart Van Assche 2017-02-01 17:13 ` Jens Axboe 2017-02-01 17:28 ` Bart Van Assche 2017-02-01 19:21 ` Bart Van Assche 2017-02-01 22:01 ` Bart Van Assche 2017-02-02 17:27 ` Bart Van Assche 2017-02-02 18:33 ` Mike Snitzer 2017-02-02 18:43 ` Bart Van Assche 2017-02-02 19:13 ` Mike Snitzer 2017-02-02 19:46 ` Bart Van Assche 2017-02-02 21:04 ` Mike Snitzer 2017-02-02 21:10 ` Mike Snitzer 2017-02-03 0:20 ` Bart Van Assche 2017-02-03 0:42 ` Mike Snitzer 2017-02-02 22:38 ` Bart Van Assche 2017-01-27 17:02 ` [dm-devel] " Bart Van Assche 2017-01-27 17:02 ` Bart Van Assche 2017-01-27 16:11 ` Jens Axboe 2017-01-27 16:11 ` Jens Axboe 2017-01-27 16:17 ` Christoph Hellwig 2017-01-27 16:17 ` Christoph Hellwig 2017-01-27 16:21 ` Jens Axboe 2017-01-27 16:21 ` Jens Axboe 2017-01-27 16:23 ` Christoph Hellwig 2017-01-27 16:23 ` Christoph Hellwig 2017-01-27 16:27 ` Jens Axboe 2017-01-27 16:27 ` Jens Axboe 2017-01-27 16:34 ` Christoph Hellwig 2017-01-27 16:34 ` Christoph Hellwig 2017-01-27 16:38 ` Jens Axboe 2017-01-27 16:38 ` Jens Axboe 2017-01-27 16:42 ` Christoph Hellwig 2017-01-27 16:42 ` Christoph Hellwig 2017-01-27 16:58 ` Jens Axboe 2017-01-27 16:58 ` Jens Axboe 2017-01-27 21:27 ` Bart Van Assche 2017-01-27 21:27 ` Bart Van Assche 2017-01-28 8:29 ` hch 2017-01-30 6:58 ` Hannes Reinecke 2017-01-30 6:58 ` Hannes Reinecke
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20170128082513.GB4728@lst.de \ --to=hch@lst.de \ --cc=Bart.VanAssche@sandisk.com \ --cc=axboe@fb.com \ --cc=dm-devel@redhat.com \ --cc=j-nomura@ce.jp.nec.com \ --cc=linux-block@vger.kernel.org \ --cc=linux-raid@vger.kernel.org \ --cc=linux-scsi@vger.kernel.org \ --cc=snitzer@redhat.com \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.