From: Christoph Hellwig <hch@lst.de>
To: Mike Snitzer <snitzer@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>,
Christoph Hellwig <hch@lst.de>,
axboe@kernel.dk, martin.petersen@oracle.com, agk@redhat.com,
shli@kernel.org, philipp.reisner@linbit.com,
linux-block@vger.kernel.org, linux-scsi@vger.kernel.org,
drbd-dev@lists.linbit.com, dm-devel@redhat.com,
linux-raid@vger.kernel.org
Subject: Re: RFC: always use REQ_OP_WRITE_ZEROES for zeroing offload
Date: Mon, 27 Mar 2017 16:57:40 +0200 [thread overview]
Message-ID: <20170327145740.GB24952@lst.de> (raw)
In-Reply-To: <20170327140307.GA13020@redhat.com>
On Mon, Mar 27, 2017 at 10:03:07AM -0400, Mike Snitzer wrote:
> By "you" I assume you're referring to Lars?
Yes.
> Lars' approach for discard,
> when drbd is layered on dm-thinp, feels over-engineered. Not his fault,
> the way discard and zeroing got conflated certainly lends itself to
> these ugly hacks. SO I do appreciate that for anything to leverage
> discard_zeroes_data it needs to be reliable. Which runs counter to how
> discard was implemented (discard may get silently dropped!) But that is
> why dm-thinp doesn't advertise dzd. Anyway...
That's exactly what this series does - remove discard_zeroes_data and
use the new REQ_OP_WRITE_ZEROES for anything that wants zeroing offload.
> As for the blkdev_issue_zeroout() resorting to manually zeroing the
> range, if the discard fails or dzd not supported, that certainly
> requires DM thinp to implement manual zeroing of the head and tail of
> the range if partial blocks are being zeroed. So I welcome any advances
> there. It is probably something that is best left to Joe or myself to
> tackle. But I'll gladly accept patches ;)
Ok, I'll happily leave this to the two of you..
next prev parent reply other threads:[~2017-03-27 14:57 UTC|newest]
Thread overview: 70+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-03-23 14:33 RFC: always use REQ_OP_WRITE_ZEROES for zeroing offload Christoph Hellwig
2017-03-23 14:33 ` [PATCH 01/23] block: renumber REQ_OP_WRITE_ZEROES Christoph Hellwig
2017-03-28 16:12 ` Bart Van Assche
2017-03-30 8:53 ` hch
2017-03-23 14:33 ` [PATCH 02/23] block: implement splitting of REQ_OP_WRITE_ZEROES bios Christoph Hellwig
2017-03-23 14:33 ` [PATCH 03/23] sd: implement REQ_OP_WRITE_ZEROES Christoph Hellwig
2017-03-28 18:50 ` Bart Van Assche
2017-03-28 19:33 ` Mike Snitzer
2017-03-29 14:51 ` Paolo Bonzini
2017-03-29 16:28 ` Bart Van Assche
2017-03-29 16:53 ` Paolo Bonzini
2017-03-30 2:25 ` Martin K. Petersen
2017-03-23 14:33 ` [PATCH 04/23] md: support REQ_OP_WRITE_ZEROES Christoph Hellwig
2017-03-23 14:33 ` [PATCH 05/23] dm: " Christoph Hellwig
2017-03-23 14:33 ` [PATCH 06/23] dm-kcopyd: switch to use REQ_OP_WRITE_ZEROES Christoph Hellwig
2017-03-23 14:55 ` Mike Snitzer
2017-03-23 14:56 ` Christoph Hellwig
2017-03-23 15:10 ` Mike Snitzer
2017-03-27 9:12 ` Christoph Hellwig
2017-03-23 14:33 ` [PATCH 07/23] block: stop using blkdev_issue_write_same for zeroing Christoph Hellwig
2017-03-23 14:33 ` [PATCH 08/23] block: add a flags argument to (__)blkdev_issue_zeroout Christoph Hellwig
2017-03-23 14:33 ` [PATCH 09/23] block: add a REQ_UNMAP flag for REQ_OP_WRITE_ZEROES Christoph Hellwig
2017-03-23 14:33 ` [PATCH 10/23] block: add a new BLKDEV_ZERO_NOFALLBACK flag Christoph Hellwig
2017-03-23 14:33 ` [PATCH 11/23] block_dev: use blkdev_issue_zerout for hole punches Christoph Hellwig
2017-03-28 16:50 ` Bart Van Assche
2017-03-30 8:59 ` hch
2017-03-23 14:33 ` [PATCH 12/23] sd: handle REQ_UNMAP Christoph Hellwig
2017-03-28 16:48 ` Bart Van Assche
2017-03-29 14:57 ` Paolo Bonzini
2017-03-30 9:02 ` hch
2017-03-30 15:28 ` Martin K. Petersen
2017-03-30 17:30 ` hch
2017-03-31 2:19 ` Martin K. Petersen
2017-03-31 7:18 ` hch
2017-03-23 14:33 ` [PATCH 13/23] nvme: implement REQ_OP_WRITE_ZEROES Christoph Hellwig
2017-03-23 14:33 ` [PATCH 14/23] zram: " Christoph Hellwig
2017-03-23 14:33 ` [PATCH 15/23] loop: " Christoph Hellwig
2017-03-23 14:33 ` [PATCH 16/23] brd: remove discard support Christoph Hellwig
2017-03-23 14:33 ` [PATCH 17/23] rbd: remove the discard_zeroes_data flag Christoph Hellwig
2017-03-23 14:33 ` [PATCH 18/23] rsxx: " Christoph Hellwig
2017-03-23 14:33 ` [PATCH 19/23] mmc: " Christoph Hellwig
2017-03-23 14:33 ` [PATCH 20/23] block: stop using discards for zeroing Christoph Hellwig
2017-03-23 14:33 ` [PATCH 21/23] drbd: make intelligent use of blkdev_issue_zeroout Christoph Hellwig
2017-03-23 14:33 ` [PATCH 22/23] drbd: implement REQ_OP_WRITE_ZEROES Christoph Hellwig
2017-03-30 10:06 ` Lars Ellenberg
2017-03-30 11:44 ` Christoph Hellwig
2017-03-30 12:50 ` [Drbd-dev] " Lars Ellenberg
2017-03-30 13:49 ` Mike Snitzer
2017-03-30 15:20 ` Martin K. Petersen
2017-03-30 23:15 ` Mike Snitzer
2017-03-31 2:34 ` Martin K. Petersen
2017-03-31 7:17 ` Christoph Hellwig
2017-03-23 14:33 ` [PATCH 23/23] block: remove the discard_zeroes_data flag Christoph Hellwig
2017-03-28 17:00 ` Bart Van Assche
2017-03-29 14:52 ` Paolo Bonzini
2017-03-30 9:06 ` hch
2017-03-30 15:29 ` Martin K. Petersen
2017-03-30 17:29 ` hch
2017-03-23 15:54 ` RFC: always use REQ_OP_WRITE_ZEROES for zeroing offload Lars Ellenberg
2017-03-23 17:02 ` Mike Snitzer
2017-03-23 22:53 ` Lars Ellenberg
2017-03-29 14:57 ` Paolo Bonzini
2017-03-27 9:10 ` Christoph Hellwig
2017-03-27 14:03 ` Mike Snitzer
2017-03-27 14:57 ` Christoph Hellwig [this message]
2017-03-27 15:08 ` [Drbd-dev] " Bart Van Assche
2017-03-30 9:04 ` Christoph Hellwig
2017-03-30 15:12 ` Mike Snitzer
2017-03-30 15:22 ` Martin K. Petersen
2017-03-30 15:38 ` Mike Snitzer
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=20170327145740.GB24952@lst.de \
--to=hch@lst.de \
--cc=agk@redhat.com \
--cc=axboe@kernel.dk \
--cc=dm-devel@redhat.com \
--cc=drbd-dev@lists.linbit.com \
--cc=hch@infradead.org \
--cc=linux-block@vger.kernel.org \
--cc=linux-raid@vger.kernel.org \
--cc=linux-scsi@vger.kernel.org \
--cc=martin.petersen@oracle.com \
--cc=philipp.reisner@linbit.com \
--cc=shli@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: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).