From: Christoph Hellwig <hch@lst.de>
To: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Jens Axboe <axboe@kernel.dk>,
linux-block@vger.kernel.org, Christoph Hellwig <hch@lst.de>,
"Martin K . Petersen" <martin.petersen@oracle.com>,
=Oleksandr Natalenko <oleksandr@natalenko.name>,
"Luis R . Rodriguez" <mcgrof@kernel.org>,
Ming Lei <ming.lei@redhat.com>, Hannes Reinecke <hare@suse.com>,
Johannes Thumshirn <jthumshirn@suse.de>
Subject: Re: [PATCH v5 7/8] scsi: Set QUEUE_FLAG_PREEMPT_ONLY while quiesced
Date: Wed, 4 Oct 2017 09:06:00 +0200 [thread overview]
Message-ID: <20171004070600.GE20879@lst.de> (raw)
In-Reply-To: <20171002225218.18548-8-bart.vanassche@wdc.com>
> + /*
> + * Ensure that the effect of blk_set_preempt_only() is globally
> + * visible before unfreezing the queue.
> + */
> + if (err == 0)
> + synchronize_rcu();
I don't understand why we'd need this. The flag is set both under
a spinlock and a mutex that are unlocked right after. That should
gurantee all the visibility we'll need.
next prev parent reply other threads:[~2017-10-04 7:06 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-10-02 22:52 [PATCH v5 0/8] block, scsi, md: Improve suspend and resume Bart Van Assche
2017-10-02 22:52 ` [PATCH v5 1/8] md: Introduce md_stop_all_writes() Bart Van Assche
2017-10-04 1:07 ` Luis R. Rodriguez
2017-10-02 22:52 ` [PATCH v5 2/8] md: Neither resync nor reshape while the system is frozen Bart Van Assche
2017-10-04 1:16 ` Luis R. Rodriguez
2017-10-04 16:58 ` Bart Van Assche
2017-10-04 16:58 ` Bart Van Assche
2017-10-04 11:30 ` Ming Lei
2017-10-04 15:38 ` Bart Van Assche
2017-10-04 15:38 ` Bart Van Assche
2017-10-02 22:52 ` [PATCH v5 3/8] block: Make q_usage_counter also track legacy requests Bart Van Assche
2017-10-02 22:52 ` [PATCH v5 4/8] block: Convert RQF_PREEMPT into REQ_PREEMPT Bart Van Assche
2017-10-04 6:57 ` Christoph Hellwig
2017-10-02 22:52 ` [PATCH v5 5/8] block: Add the QUEUE_FLAG_PREEMPT_ONLY request queue flag Bart Van Assche
2017-10-04 6:58 ` Christoph Hellwig
2017-10-02 22:52 ` [PATCH v5 6/8] scsi: Reduce suspend latency Bart Van Assche
2017-10-04 7:04 ` Christoph Hellwig
2017-10-04 15:41 ` Bart Van Assche
2017-10-02 22:52 ` [PATCH v5 7/8] scsi: Set QUEUE_FLAG_PREEMPT_ONLY while quiesced Bart Van Assche
2017-10-04 7:06 ` Christoph Hellwig [this message]
2017-10-04 15:44 ` Bart Van Assche
2017-10-02 22:52 ` [PATCH v5 8/8] block: Make SCSI device suspend and resume work reliably Bart Van Assche
2017-10-04 7:06 ` Christoph Hellwig
2017-10-04 15:45 ` Bart Van Assche
2017-10-03 16:01 ` [PATCH v5 0/8] block, scsi, md: Improve suspend and resume Oleksandr Natalenko
2017-10-04 6:56 ` Christoph Hellwig
2017-10-04 7:53 ` Ming Lei
2017-10-04 7:56 ` Ming Lei
2017-10-04 15:18 ` Bart Van Assche
2017-10-04 15:31 ` Ming Lei
2017-10-04 22:36 ` Bart Van Assche
2017-10-04 15:21 ` Bart Van Assche
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=20171004070600.GE20879@lst.de \
--to=hch@lst.de \
--cc=axboe@kernel.dk \
--cc=bart.vanassche@wdc.com \
--cc=hare@suse.com \
--cc=jthumshirn@suse.de \
--cc=linux-block@vger.kernel.org \
--cc=martin.petersen@oracle.com \
--cc=mcgrof@kernel.org \
--cc=ming.lei@redhat.com \
--cc=oleksandr@natalenko.name \
/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 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.