All of lore.kernel.org
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@lst.de>
To: Jens Axboe <axboe@kernel.dk>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>,
	Minchan Kim <minchan@kernel.org>, Nitin Gupta <ngupta@vflare.org>,
	dm-devel@redhat.com, linux-block@vger.kernel.org,
	drbd-dev@lists.linbit.com, linux-bcache@vger.kernel.org,
	linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org
Subject: [PATCH 16/16] block: reduce part_stat_lock() scope
Date: Mon, 25 May 2020 13:30:14 +0200	[thread overview]
Message-ID: <20200525113014.345997-17-hch@lst.de> (raw)
In-Reply-To: <20200525113014.345997-1-hch@lst.de>

We only need the stats lock (aka preempt_disable()) for updating the
states, not for looking up or dropping the hd_struct reference.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 block/blk-core.c  | 5 +++--
 block/blk-merge.c | 3 ++-
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/block/blk-core.c b/block/blk-core.c
index bf2f7d4bc0c1c..a01fb2b508f0e 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1437,9 +1437,9 @@ void blk_account_io_done(struct request *req, u64 now)
 		update_io_ticks(part, jiffies, true);
 		part_stat_inc(part, ios[sgrp]);
 		part_stat_add(part, nsecs[sgrp], now - req->start_time_ns);
+		part_stat_unlock();
 
 		hd_struct_put(part);
-		part_stat_unlock();
 	}
 }
 
@@ -1448,8 +1448,9 @@ void blk_account_io_start(struct request *rq)
 	if (!blk_do_io_stat(rq))
 		return;
 
-	part_stat_lock();
 	rq->part = disk_map_sector_rcu(rq->rq_disk, blk_rq_pos(rq));
+
+	part_stat_lock();
 	update_io_ticks(rq->part, jiffies, false);
 	part_stat_unlock();
 }
diff --git a/block/blk-merge.c b/block/blk-merge.c
index c3beae5c1be71..f0b0bae075a0c 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -674,8 +674,9 @@ static void blk_account_io_merge_request(struct request *req)
 	if (blk_do_io_stat(req)) {
 		part_stat_lock();
 		part_stat_inc(req->part, merges[op_stat_group(req_op(req))]);
-		hd_struct_put(req->part);
 		part_stat_unlock();
+
+		hd_struct_put(req->part);
 	}
 }
 
-- 
2.26.2
_______________________________________________
Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org
To unsubscribe send an email to linux-nvdimm-leave@lists.01.org

WARNING: multiple messages have this Message-ID (diff)
From: Christoph Hellwig <hch@lst.de>
To: Jens Axboe <axboe@kernel.dk>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>,
	Minchan Kim <minchan@kernel.org>, Nitin Gupta <ngupta@vflare.org>,
	dm-devel@redhat.com, linux-block@vger.kernel.org,
	drbd-dev@lists.linbit.com, linux-bcache@vger.kernel.org,
	linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org
Subject: [PATCH 16/16] block: reduce part_stat_lock() scope
Date: Mon, 25 May 2020 13:30:14 +0200	[thread overview]
Message-ID: <20200525113014.345997-17-hch@lst.de> (raw)
In-Reply-To: <20200525113014.345997-1-hch@lst.de>

We only need the stats lock (aka preempt_disable()) for updating the
states, not for looking up or dropping the hd_struct reference.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 block/blk-core.c  | 5 +++--
 block/blk-merge.c | 3 ++-
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/block/blk-core.c b/block/blk-core.c
index bf2f7d4bc0c1c..a01fb2b508f0e 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1437,9 +1437,9 @@ void blk_account_io_done(struct request *req, u64 now)
 		update_io_ticks(part, jiffies, true);
 		part_stat_inc(part, ios[sgrp]);
 		part_stat_add(part, nsecs[sgrp], now - req->start_time_ns);
+		part_stat_unlock();
 
 		hd_struct_put(part);
-		part_stat_unlock();
 	}
 }
 
@@ -1448,8 +1448,9 @@ void blk_account_io_start(struct request *rq)
 	if (!blk_do_io_stat(rq))
 		return;
 
-	part_stat_lock();
 	rq->part = disk_map_sector_rcu(rq->rq_disk, blk_rq_pos(rq));
+
+	part_stat_lock();
 	update_io_ticks(rq->part, jiffies, false);
 	part_stat_unlock();
 }
diff --git a/block/blk-merge.c b/block/blk-merge.c
index c3beae5c1be71..f0b0bae075a0c 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -674,8 +674,9 @@ static void blk_account_io_merge_request(struct request *req)
 	if (blk_do_io_stat(req)) {
 		part_stat_lock();
 		part_stat_inc(req->part, merges[op_stat_group(req_op(req))]);
-		hd_struct_put(req->part);
 		part_stat_unlock();
+
+		hd_struct_put(req->part);
 	}
 }
 
-- 
2.26.2


  parent reply	other threads:[~2020-05-25 11:31 UTC|newest]

Thread overview: 43+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-05-25 11:29 block I/O accounting improvements Christoph Hellwig
2020-05-25 11:29 ` Christoph Hellwig
2020-05-25 11:29 ` [PATCH 01/16] block: add disk/bio-based accounting helpers Christoph Hellwig
2020-05-25 11:29   ` Christoph Hellwig
2020-05-25 12:28   ` Konstantin Khlebnikov
2020-05-27  5:23     ` Christoph Hellwig
2020-05-27  5:23       ` Christoph Hellwig
2020-05-27  5:23       ` Christoph Hellwig
2020-05-25 11:30 ` [PATCH 02/16] drbd: use bio_{start,end}_io_acct Christoph Hellwig
2020-05-25 11:30   ` Christoph Hellwig
2020-05-25 11:30 ` [PATCH 03/16] rsxx: " Christoph Hellwig
2020-05-25 11:30   ` Christoph Hellwig
2020-05-25 11:30 ` [PATCH 04/16] lightnvm/pblk: " Christoph Hellwig
2020-05-25 11:30   ` Christoph Hellwig
2020-05-25 11:30 ` [PATCH 05/16] bcache: " Christoph Hellwig
2020-05-25 11:30   ` Christoph Hellwig
2020-05-25 13:03   ` Coly Li
2020-05-25 13:03     ` Coly Li
2020-05-25 11:30 ` [PATCH 06/16] dm: " Christoph Hellwig
2020-05-25 11:30   ` Christoph Hellwig
2020-05-25 11:30 ` [PATCH 07/16] nvdimm: " Christoph Hellwig
2020-05-25 11:30   ` Christoph Hellwig
2020-05-25 11:30 ` [PATCH 08/16] zram: nvdimm: use bio_{start,end}_io_acct and disk_{start,end}_io_acct Christoph Hellwig
2020-05-25 11:30   ` Christoph Hellwig
2020-05-25 11:30 ` [PATCH 09/16] block: remove generic_{start,end}_io_acct Christoph Hellwig
2020-05-25 11:30   ` Christoph Hellwig
2020-05-25 11:30 ` [PATCH 10/16] block: move update_io_ticks to blk-core.c Christoph Hellwig
2020-05-25 11:30   ` Christoph Hellwig
2020-05-25 11:30 ` [PATCH 11/16] block: always use a percpu variable for disk stats Christoph Hellwig
2020-05-25 11:30   ` Christoph Hellwig
2020-05-25 11:30 ` [PATCH 12/16] block: account merge of two requests Christoph Hellwig
2020-05-25 11:30   ` Christoph Hellwig
2020-05-25 11:30 ` [PATCH 13/16] block: add a blk_account_io_merge_bio helper Christoph Hellwig
2020-05-25 11:30   ` Christoph Hellwig
2020-05-25 11:30 ` [PATCH 14/16] block: remove rcu_read_lock() from part_stat_lock() Christoph Hellwig
2020-05-25 11:30   ` Christoph Hellwig
2020-05-25 11:30 ` [PATCH 15/16] block: use __this_cpu_add() instead of access by smp_processor_id() Christoph Hellwig
2020-05-25 11:30   ` Christoph Hellwig
2020-05-25 11:30 ` Christoph Hellwig [this message]
2020-05-25 11:30   ` [PATCH 16/16] block: reduce part_stat_lock() scope Christoph Hellwig
2020-05-25 12:34 ` block I/O accounting improvements Konstantin Khlebnikov
2020-05-27  5:24 block I/O accounting improvements v2 Christoph Hellwig
2020-05-27  5:24 ` [PATCH 16/16] block: reduce part_stat_lock() scope Christoph Hellwig
2020-05-27  5:24   ` Christoph Hellwig

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=20200525113014.345997-17-hch@lst.de \
    --to=hch@lst.de \
    --cc=axboe@kernel.dk \
    --cc=dm-devel@redhat.com \
    --cc=drbd-dev@lists.linbit.com \
    --cc=khlebnikov@yandex-team.ru \
    --cc=linux-bcache@vger.kernel.org \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-nvdimm@lists.01.org \
    --cc=minchan@kernel.org \
    --cc=ngupta@vflare.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 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.