linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Josef Bacik <josef@toxicpanda.com>
To: axboe@kernel.dk, kernel-team@fb.com, linux-block@vger.kernel.org,
	akpm@linux-foundation.org, hannes@cmpxchg.org,
	linux-kernel@vger.kernel.org, tj@kernel.org,
	linux-fsdevel@vger.kernel.org
Cc: Josef Bacik <jbacik@fb.com>
Subject: [PATCH 04/13] blk: introduce REQ_SWAP
Date: Tue,  5 Jun 2018 09:29:39 -0400	[thread overview]
Message-ID: <20180605132948.1664-5-josef@toxicpanda.com> (raw)
In-Reply-To: <20180605132948.1664-1-josef@toxicpanda.com>

From: Josef Bacik <jbacik@fb.com>

Just like REQ_META, it's important to know the IO coming down is swap
in order to guard against potential IO priority inversion issues with
cgroups.  Add REQ_SWAP and use it for all swap IO, and add it to our
bio_issue_as_root_blkg helper.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Acked-by: Tejun Heo <tj@kernel.org>
---
 include/linux/blk-cgroup.h | 2 +-
 include/linux/blk_types.h  | 3 ++-
 mm/page_io.c               | 2 +-
 3 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h
index b41292726c0f..a8f9ba8f33a4 100644
--- a/include/linux/blk-cgroup.h
+++ b/include/linux/blk-cgroup.h
@@ -254,7 +254,7 @@ static inline struct blkcg *bio_blkcg(struct bio *bio)
  */
 static inline bool bio_issue_as_root_blkg(struct bio *bio)
 {
-	return (bio->bi_opf & REQ_META);
+	return (bio->bi_opf & (REQ_META | REQ_SWAP)) != 0;
 }
 
 /**
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index ff181df8c195..4f7ba397d37d 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -327,7 +327,7 @@ enum req_flag_bits {
 
 	/* for driver use */
 	__REQ_DRV,
-
+	__REQ_SWAP,		/* swapping request. */
 	__REQ_NR_BITS,		/* stops here */
 };
 
@@ -349,6 +349,7 @@ enum req_flag_bits {
 #define REQ_NOUNMAP		(1ULL << __REQ_NOUNMAP)
 
 #define REQ_DRV			(1ULL << __REQ_DRV)
+#define REQ_SWAP		(1ULL << __REQ_SWAP)
 
 #define REQ_FAILFAST_MASK \
 	(REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER)
diff --git a/mm/page_io.c b/mm/page_io.c
index b41cf9644585..a552cb37e220 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -338,7 +338,7 @@ int __swap_writepage(struct page *page, struct writeback_control *wbc,
 		ret = -ENOMEM;
 		goto out;
 	}
-	bio->bi_opf = REQ_OP_WRITE | wbc_to_write_flags(wbc);
+	bio->bi_opf = REQ_OP_WRITE | REQ_SWAP | wbc_to_write_flags(wbc);
 	count_swpout_vm_event(page);
 	set_page_writeback(page);
 	unlock_page(page);
-- 
2.14.3

  parent reply	other threads:[~2018-06-05 13:29 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-06-05 13:29 [PATCH 00/13][V2] Introduce io.latency io controller for cgroups Josef Bacik
2018-06-05 13:29 ` [PATCH 01/13] block: add bi_blkg to the bio " Josef Bacik
2018-06-05 13:29 ` [PATCH 02/13] block: introduce bio_issue_as_root_blkg Josef Bacik
2018-06-05 13:29 ` [PATCH 03/13] blk-cgroup: allow controllers to output their own stats Josef Bacik
2018-06-05 13:29 ` Josef Bacik [this message]
2018-06-05 13:29 ` [PATCH 05/13] swap,blkcg: issue swap io with the appropriate context Josef Bacik
2018-06-05 19:41   ` Tejun Heo
2018-06-11 14:06   ` Johannes Weiner
2018-06-05 13:29 ` [PATCH 06/13] blkcg: add generic throttling mechanism Josef Bacik
2018-06-05 20:45   ` Tejun Heo
2018-06-05 13:29 ` [PATCH 07/13] memcontrol: schedule throttling if we are congested Josef Bacik
2018-06-05 20:46   ` Tejun Heo
2018-06-11 14:08   ` Johannes Weiner
2018-06-05 13:29 ` [PATCH 08/13] blk-stat: export helpers for modifying blk_rq_stat Josef Bacik
2018-06-05 13:29 ` [PATCH 09/13] blk-rq-qos: refactor out common elements of blk-wbt Josef Bacik
2018-06-05 13:29 ` [PATCH 10/13] block: remove external dependency on wbt_flags Josef Bacik
2018-06-05 13:29 ` [PATCH 11/13] rq-qos: introduce dio_bio callback Josef Bacik
2018-06-05 13:29 ` [PATCH 12/13] block: introduce blk-iolatency io controller Josef Bacik
2018-06-05 13:29 ` [PATCH 13/13] Documentation: add a doc for blk-iolatency Josef Bacik
  -- strict thread matches above, loose matches on Subject: below --
2018-05-29 21:17 [PATCH 00/13] Introdue io.latency io controller for cgroups Josef Bacik
2018-05-29 21:17 ` [PATCH 04/13] blk: introduce REQ_SWAP Josef Bacik
2018-05-30 15:58   ` Tejun Heo

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=20180605132948.1664-5-josef@toxicpanda.com \
    --to=josef@toxicpanda.com \
    --cc=akpm@linux-foundation.org \
    --cc=axboe@kernel.dk \
    --cc=hannes@cmpxchg.org \
    --cc=jbacik@fb.com \
    --cc=kernel-team@fb.com \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=tj@kernel.org \
    --subject='Re: [PATCH 04/13] blk: introduce REQ_SWAP' \
    /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

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).