From: Sergei Shtepa <sergei.shtepa@veeam.com>
To: <Damien.LeMoal@wdc.com>, <snitzer@redhat.com>, <hare@suse.de>,
<ming.lei@redhat.com>, <agk@redhat.com>, <corbet@lwn.net>,
<axboe@kernel.dk>, <jack@suse.cz>, <johannes.thumshirn@wdc.com>,
<gregkh@linuxfoundation.org>, <koct9i@gmail.com>, <steve@sk2.org>,
<dm-devel@redhat.com>, <linux-block@vger.kernel.org>,
<linux-doc@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Cc: <sergei.shtepa@veeam.com>, <pavgel.tide@veeam.com>
Subject: [PATCH v4 3/6] block: add blk_mq_is_queue_frozen()
Date: Wed, 3 Feb 2021 18:53:55 +0300 [thread overview]
Message-ID: <1612367638-3794-4-git-send-email-sergei.shtepa@veeam.com> (raw)
In-Reply-To: <1612367638-3794-1-git-send-email-sergei.shtepa@veeam.com>
blk_mq_is_queue_frozen() allow to assert that the queue is frozen.
Signed-off-by: Sergei Shtepa <sergei.shtepa@veeam.com>
---
block/blk-mq.c | 13 +++++++++++++
include/linux/blk-mq.h | 1 +
2 files changed, 14 insertions(+)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index f285a9123a8b..924ec26fae5f 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -161,6 +161,19 @@ int blk_mq_freeze_queue_wait_timeout(struct request_queue *q,
}
EXPORT_SYMBOL_GPL(blk_mq_freeze_queue_wait_timeout);
+
+bool blk_mq_is_queue_frozen(struct request_queue *q)
+{
+ bool ret;
+
+ mutex_lock(&q->mq_freeze_lock);
+ ret = percpu_ref_is_dying(&q->q_usage_counter) && percpu_ref_is_zero(&q->q_usage_counter);
+ mutex_unlock(&q->mq_freeze_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(blk_mq_is_queue_frozen);
+
/*
* Guarantee no request is in use, so we can change any data structure of
* the queue afterward.
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index d705b174d346..9d1e8c4e922e 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -525,6 +525,7 @@ void blk_freeze_queue_start(struct request_queue *q);
void blk_mq_freeze_queue_wait(struct request_queue *q);
int blk_mq_freeze_queue_wait_timeout(struct request_queue *q,
unsigned long timeout);
+bool blk_mq_is_queue_frozen(struct request_queue *q);
int blk_mq_map_queues(struct blk_mq_queue_map *qmap);
void blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, int nr_hw_queues);
--
2.20.1
next prev parent reply other threads:[~2021-02-03 16:07 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-03 15:53 [PATCH v4 0/6] block-layer interposer Sergei Shtepa
2021-02-03 15:53 ` [PATCH v4 1/6] docs: device-mapper: add remap_and_filter Sergei Shtepa
2021-02-04 4:15 ` Randy Dunlap
2021-02-04 9:44 ` Sergei Shtepa
2021-02-03 15:53 ` [PATCH v4 2/6] block: add blk_interposer Sergei Shtepa
2021-02-03 16:18 ` Mike Snitzer
2021-02-04 10:06 ` Sergei Shtepa
2021-02-03 15:53 ` Sergei Shtepa [this message]
2021-02-03 16:09 ` [PATCH v4 3/6] block: add blk_mq_is_queue_frozen() Mike Snitzer
2021-02-03 15:53 ` [PATCH v4 4/6] dm: new ioctl DM_DEV_REMAP_CMD Sergei Shtepa
2021-02-03 16:00 ` Greg KH
2021-02-03 15:53 ` [PATCH v4 5/6] dm: add 'noexcl' option for dm-linear Sergei Shtepa
2021-02-03 15:53 ` [PATCH v4 6/6] docs: device-mapper: " Sergei Shtepa
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=1612367638-3794-4-git-send-email-sergei.shtepa@veeam.com \
--to=sergei.shtepa@veeam.com \
--cc=Damien.LeMoal@wdc.com \
--cc=agk@redhat.com \
--cc=axboe@kernel.dk \
--cc=corbet@lwn.net \
--cc=dm-devel@redhat.com \
--cc=gregkh@linuxfoundation.org \
--cc=hare@suse.de \
--cc=jack@suse.cz \
--cc=johannes.thumshirn@wdc.com \
--cc=koct9i@gmail.com \
--cc=linux-block@vger.kernel.org \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=ming.lei@redhat.com \
--cc=pavgel.tide@veeam.com \
--cc=snitzer@redhat.com \
--cc=steve@sk2.org \
/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).