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* [PATCH v2 0/3] block: drive-by cleanups for block cgroup
@ 2020-04-30 15:03 Johannes Thumshirn
  2020-04-30 15:03 ` [PATCH v2 1/3] block: remove blk_queue_root_blkg Johannes Thumshirn
                   ` (4 more replies)
  0 siblings, 5 replies; 6+ messages in thread
From: Johannes Thumshirn @ 2020-04-30 15:03 UTC (permalink / raw)
  To: Jens Axboe; +Cc: linux-block, Johannes Thumshirn

While reviewing Christoph's bio cleanup series, I noticed
blkcg_bio_issue_check() is way too big for an inline function. When I moved it
into block/blk-cgroup.c I noticed two other functions which only have one or
no callers at all, so I cleaned them up as well.


Changes to v1:
- Re-based onto for-5.8/block with Christoph's patches
- Removed white-space to not hurt Christoph's feelings
- Added Reviewed-bys

Johannes Thumshirn (3):
  block: remove blk_queue_root_blkg
  block: move blkcg_bio_issue_check out of line
  block: open-code blkg_path in it's sole caller

 block/bfq-cgroup.c         |  3 +-
 block/blk-cgroup.c         | 57 +++++++++++++++++++++++++
 include/linux/blk-cgroup.h | 87 +-------------------------------------
 3 files changed, 60 insertions(+), 87 deletions(-)

-- 
2.24.1


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [PATCH v2 1/3] block: remove blk_queue_root_blkg
  2020-04-30 15:03 [PATCH v2 0/3] block: drive-by cleanups for block cgroup Johannes Thumshirn
@ 2020-04-30 15:03 ` Johannes Thumshirn
  2020-04-30 15:03 ` [PATCH v2 2/3] block: move blkcg_bio_issue_check out of line Johannes Thumshirn
                   ` (3 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: Johannes Thumshirn @ 2020-04-30 15:03 UTC (permalink / raw)
  To: Jens Axboe; +Cc: linux-block, Johannes Thumshirn, Christoph Hellwig

blk_queue_root_blkg() has no callers, remove it.

Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 include/linux/blk-cgroup.h | 13 -------------
 1 file changed, 13 deletions(-)

diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h
index 4deb8bb7b6af..a606767cdcc7 100644
--- a/include/linux/blk-cgroup.h
+++ b/include/linux/blk-cgroup.h
@@ -364,17 +364,6 @@ static inline struct blkcg_gq *blkg_lookup(struct blkcg *blkcg,
 	return __blkg_lookup(blkcg, q, false);
 }
 
-/**
- * blk_queue_root_blkg - return blkg for the (blkcg_root, @q) pair
- * @q: request_queue of interest
- *
- * Lookup blkg for @q at the root level. See also blkg_lookup().
- */
-static inline struct blkcg_gq *blk_queue_root_blkg(struct request_queue *q)
-{
-	return q->root_blkg;
-}
-
 /**
  * blkg_to_pdata - get policy private data
  * @blkg: blkg of interest
@@ -709,8 +698,6 @@ static inline bool blk_cgroup_congested(void) { return false; }
 static inline void blkcg_schedule_throttle(struct request_queue *q, bool use_memdelay) { }
 
 static inline struct blkcg_gq *blkg_lookup(struct blkcg *blkcg, void *key) { return NULL; }
-static inline struct blkcg_gq *blk_queue_root_blkg(struct request_queue *q)
-{ return NULL; }
 static inline int blkcg_init_queue(struct request_queue *q) { return 0; }
 static inline void blkcg_exit_queue(struct request_queue *q) { }
 static inline int blkcg_policy_register(struct blkcg_policy *pol) { return 0; }
-- 
2.24.1


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v2 2/3] block: move blkcg_bio_issue_check out of line
  2020-04-30 15:03 [PATCH v2 0/3] block: drive-by cleanups for block cgroup Johannes Thumshirn
  2020-04-30 15:03 ` [PATCH v2 1/3] block: remove blk_queue_root_blkg Johannes Thumshirn
@ 2020-04-30 15:03 ` Johannes Thumshirn
  2020-04-30 15:03 ` [PATCH v2 3/3] block: open-code blkg_path in it's sole caller Johannes Thumshirn
                   ` (2 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: Johannes Thumshirn @ 2020-04-30 15:03 UTC (permalink / raw)
  To: Jens Axboe; +Cc: linux-block, Johannes Thumshirn, Christoph Hellwig

blkcg_bio_issue_check() is way to big to be an inline function, move it to
the other blkcg related functions in block/blk-cgroup.c.

According to the bloat-o-meter this brings it's sole caller
generic_make_request_checks() down from 2417 to 1881 bytes (~22%).

$ ./scripts/bloat-o-meter -t vmlinux.old vmlinux
add/remove: 1/0 grow/shrink: 1/1 up/down: 667/-539 (128)
Function                                     old     new   delta
blkcg_bio_issue_check                          -     664    +664
generic_make_request_checks.cold              45      48      +3
generic_make_request_checks                 2372    1833    -539
Total: Before=9624970, After=9625098, chg +0.00%

Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 block/blk-cgroup.c         | 57 ++++++++++++++++++++++++++++++++++++
 include/linux/blk-cgroup.h | 60 +-------------------------------------
 2 files changed, 58 insertions(+), 59 deletions(-)

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index c5dc833212e1..88453cb866bb 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -1706,6 +1706,63 @@ void blkcg_schedule_throttle(struct request_queue *q, bool use_memdelay)
 	set_notify_resume(current);
 }
 
+bool blkcg_bio_issue_check(struct request_queue *q, struct bio *bio)
+{
+	struct blkcg_gq *blkg;
+	bool throtl = false;
+
+	rcu_read_lock();
+
+	if (!bio->bi_blkg) {
+		char b[BDEVNAME_SIZE];
+
+		WARN_ONCE(1,
+			  "no blkg associated for bio on block-device: %s\n",
+			  bio_devname(bio, b));
+		bio_associate_blkg(bio);
+	}
+
+	blkg = bio->bi_blkg;
+
+	throtl = blk_throtl_bio(q, blkg, bio);
+	if (!throtl) {
+		struct blkg_iostat_set *bis;
+		int rwd, cpu;
+
+		if (op_is_discard(bio->bi_opf))
+			rwd = BLKG_IOSTAT_DISCARD;
+		else if (op_is_write(bio->bi_opf))
+			rwd = BLKG_IOSTAT_WRITE;
+		else
+			rwd = BLKG_IOSTAT_READ;
+
+		cpu = get_cpu();
+		bis = per_cpu_ptr(blkg->iostat_cpu, cpu);
+		u64_stats_update_begin(&bis->sync);
+
+		/*
+		 * If the bio is flagged with BIO_CGROUP_ACCT it means this is a
+		 * split bio and we would have already accounted for the size of
+		 * the bio.
+		 */
+		if (!bio_flagged(bio, BIO_CGROUP_ACCT)) {
+			bio_set_flag(bio, BIO_CGROUP_ACCT);
+			bis->cur.bytes[rwd] += bio->bi_iter.bi_size;
+		}
+		bis->cur.ios[rwd]++;
+
+		u64_stats_update_end(&bis->sync);
+		if (cgroup_subsys_on_dfl(io_cgrp_subsys))
+			cgroup_rstat_updated(blkg->blkcg->css.cgroup, cpu);
+		put_cpu();
+	}
+
+	blkcg_bio_issue_init(bio);
+
+	rcu_read_unlock();
+	return !throtl;
+}
+
 /**
  * blkcg_add_delay - add delay to this blkg
  * @blkg: blkg of interest
diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h
index a606767cdcc7..b356d4eed08d 100644
--- a/include/linux/blk-cgroup.h
+++ b/include/linux/blk-cgroup.h
@@ -559,65 +559,6 @@ static inline void blkcg_bio_issue_init(struct bio *bio)
 	bio_issue_init(&bio->bi_issue, bio_sectors(bio));
 }
 
-static inline bool blkcg_bio_issue_check(struct request_queue *q,
-					 struct bio *bio)
-{
-	struct blkcg_gq *blkg;
-	bool throtl = false;
-
-	rcu_read_lock();
-
-	if (!bio->bi_blkg) {
-		char b[BDEVNAME_SIZE];
-
-		WARN_ONCE(1,
-			  "no blkg associated for bio on block-device: %s\n",
-			  bio_devname(bio, b));
-		bio_associate_blkg(bio);
-	}
-
-	blkg = bio->bi_blkg;
-
-	throtl = blk_throtl_bio(q, blkg, bio);
-
-	if (!throtl) {
-		struct blkg_iostat_set *bis;
-		int rwd, cpu;
-
-		if (op_is_discard(bio->bi_opf))
-			rwd = BLKG_IOSTAT_DISCARD;
-		else if (op_is_write(bio->bi_opf))
-			rwd = BLKG_IOSTAT_WRITE;
-		else
-			rwd = BLKG_IOSTAT_READ;
-
-		cpu = get_cpu();
-		bis = per_cpu_ptr(blkg->iostat_cpu, cpu);
-		u64_stats_update_begin(&bis->sync);
-
-		/*
-		 * If the bio is flagged with BIO_CGROUP_ACCT it means this is a
-		 * split bio and we would have already accounted for the size of
-		 * the bio.
-		 */
-		if (!bio_flagged(bio, BIO_CGROUP_ACCT)) {
-			bio_set_flag(bio, BIO_CGROUP_ACCT);
-			bis->cur.bytes[rwd] += bio->bi_iter.bi_size;
-		}
-		bis->cur.ios[rwd]++;
-
-		u64_stats_update_end(&bis->sync);
-		if (cgroup_subsys_on_dfl(io_cgrp_subsys))
-			cgroup_rstat_updated(blkg->blkcg->css.cgroup, cpu);
-		put_cpu();
-	}
-
-	blkcg_bio_issue_init(bio);
-
-	rcu_read_unlock();
-	return !throtl;
-}
-
 static inline void blkcg_use_delay(struct blkcg_gq *blkg)
 {
 	if (atomic_add_return(1, &blkg->use_delay) == 1)
@@ -668,6 +609,7 @@ static inline void blkcg_clear_delay(struct blkcg_gq *blkg)
 	}
 }
 
+bool blkcg_bio_issue_check(struct request_queue *q, struct bio *bio);
 void blkcg_add_delay(struct blkcg_gq *blkg, u64 now, u64 delta);
 void blkcg_schedule_throttle(struct request_queue *q, bool use_memdelay);
 void blkcg_maybe_throttle_current(void);
-- 
2.24.1


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v2 3/3] block: open-code blkg_path in it's sole caller
  2020-04-30 15:03 [PATCH v2 0/3] block: drive-by cleanups for block cgroup Johannes Thumshirn
  2020-04-30 15:03 ` [PATCH v2 1/3] block: remove blk_queue_root_blkg Johannes Thumshirn
  2020-04-30 15:03 ` [PATCH v2 2/3] block: move blkcg_bio_issue_check out of line Johannes Thumshirn
@ 2020-04-30 15:03 ` Johannes Thumshirn
  2020-05-04 15:31 ` [PATCH v2 0/3] block: drive-by cleanups for block cgroup Johannes Thumshirn
  2020-05-08 10:33 ` Johannes Thumshirn
  4 siblings, 0 replies; 6+ messages in thread
From: Johannes Thumshirn @ 2020-04-30 15:03 UTC (permalink / raw)
  To: Jens Axboe; +Cc: linux-block, Johannes Thumshirn, Christoph Hellwig

blkg_path() is a trivial one-line helper that only has a single caller,
bfq_bic_update_cgroup().

Remove blkg_path() and open-code it in bfq_bic_update_cgroup().

Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 block/bfq-cgroup.c         |  3 ++-
 include/linux/blk-cgroup.h | 14 --------------
 2 files changed, 2 insertions(+), 15 deletions(-)

diff --git a/block/bfq-cgroup.c b/block/bfq-cgroup.c
index 68882b9b8f11..8fe7d47eb4dd 100644
--- a/block/bfq-cgroup.c
+++ b/block/bfq-cgroup.c
@@ -794,7 +794,8 @@ void bfq_bic_update_cgroup(struct bfq_io_cq *bic, struct bio *bio)
 	 * refcounter for bfqg, to let it disappear only after no
 	 * bfq_queue refers to it any longer.
 	 */
-	blkg_path(bfqg_to_blkg(bfqg), bfqg->blkg_path, sizeof(bfqg->blkg_path));
+	cgroup_path(bfqg_to_blkg(bfqg)->blkcg->css.cgroup, bfqg->blkg_path,
+		    sizeof(bfqg->blkg_path));
 	bic->blkcg_serial_nr = serial_nr;
 out:
 	rcu_read_unlock();
diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h
index b356d4eed08d..3e61298fae6a 100644
--- a/include/linux/blk-cgroup.h
+++ b/include/linux/blk-cgroup.h
@@ -433,19 +433,6 @@ static inline void blkcg_unpin_online(struct blkcg *blkcg)
 	} while (blkcg);
 }
 
-/**
- * blkg_path - format cgroup path of blkg
- * @blkg: blkg of interest
- * @buf: target buffer
- * @buflen: target buffer length
- *
- * Format the path of the cgroup of @blkg into @buf.
- */
-static inline int blkg_path(struct blkcg_gq *blkg, char *buf, int buflen)
-{
-	return cgroup_path(blkg->blkcg->css.cgroup, buf, buflen);
-}
-
 /**
  * blkg_get - get a blkg reference
  * @blkg: blkg to get
@@ -655,7 +642,6 @@ static inline struct blkcg *bio_blkcg(struct bio *bio) { return NULL; }
 static inline struct blkg_policy_data *blkg_to_pd(struct blkcg_gq *blkg,
 						  struct blkcg_policy *pol) { return NULL; }
 static inline struct blkcg_gq *pd_to_blkg(struct blkg_policy_data *pd) { return NULL; }
-static inline char *blkg_path(struct blkcg_gq *blkg) { return NULL; }
 static inline void blkg_get(struct blkcg_gq *blkg) { }
 static inline void blkg_put(struct blkcg_gq *blkg) { }
 
-- 
2.24.1


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* Re: [PATCH v2 0/3] block: drive-by cleanups for block cgroup
  2020-04-30 15:03 [PATCH v2 0/3] block: drive-by cleanups for block cgroup Johannes Thumshirn
                   ` (2 preceding siblings ...)
  2020-04-30 15:03 ` [PATCH v2 3/3] block: open-code blkg_path in it's sole caller Johannes Thumshirn
@ 2020-05-04 15:31 ` Johannes Thumshirn
  2020-05-08 10:33 ` Johannes Thumshirn
  4 siblings, 0 replies; 6+ messages in thread
From: Johannes Thumshirn @ 2020-05-04 15:31 UTC (permalink / raw)
  To: Jens Axboe; +Cc: linux-block

On 30/04/2020 17:04, Johannes Thumshirn wrote:
> While reviewing Christoph's bio cleanup series, I noticed
> blkcg_bio_issue_check() is way too big for an inline function. When I moved it
> into block/blk-cgroup.c I noticed two other functions which only have one or
> no callers at all, so I cleaned them up as well.
> 
> 
> Changes to v1:
> - Re-based onto for-5.8/block with Christoph's patches
> - Removed white-space to not hurt Christoph's feelings
> - Added Reviewed-bys
> 
> Johannes Thumshirn (3):
>    block: remove blk_queue_root_blkg
>    block: move blkcg_bio_issue_check out of line
>    block: open-code blkg_path in it's sole caller
> 
>   block/bfq-cgroup.c         |  3 +-
>   block/blk-cgroup.c         | 57 +++++++++++++++++++++++++
>   include/linux/blk-cgroup.h | 87 +-------------------------------------
>   3 files changed, 60 insertions(+), 87 deletions(-)
> 

Jens, any comments?

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v2 0/3] block: drive-by cleanups for block cgroup
  2020-04-30 15:03 [PATCH v2 0/3] block: drive-by cleanups for block cgroup Johannes Thumshirn
                   ` (3 preceding siblings ...)
  2020-05-04 15:31 ` [PATCH v2 0/3] block: drive-by cleanups for block cgroup Johannes Thumshirn
@ 2020-05-08 10:33 ` Johannes Thumshirn
  4 siblings, 0 replies; 6+ messages in thread
From: Johannes Thumshirn @ 2020-05-08 10:33 UTC (permalink / raw)
  To: Jens Axboe; +Cc: linux-block

On 30/04/2020 17:04, Johannes Thumshirn wrote:
> While reviewing Christoph's bio cleanup series, I noticed
> blkcg_bio_issue_check() is way too big for an inline function. When I moved it
> into block/blk-cgroup.c I noticed two other functions which only have one or
> no callers at all, so I cleaned them up as well.
> 
> 
> Changes to v1:
> - Re-based onto for-5.8/block with Christoph's patches
> - Removed white-space to not hurt Christoph's feelings
> - Added Reviewed-bys
> 
> Johannes Thumshirn (3):
>    block: remove blk_queue_root_blkg
>    block: move blkcg_bio_issue_check out of line
>    block: open-code blkg_path in it's sole caller
> 
>   block/bfq-cgroup.c         |  3 +-
>   block/blk-cgroup.c         | 57 +++++++++++++++++++++++++
>   include/linux/blk-cgroup.h | 87 +-------------------------------------
>   3 files changed, 60 insertions(+), 87 deletions(-)
> 

Ping?

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2020-05-08 10:33 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
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2020-04-30 15:03 [PATCH v2 0/3] block: drive-by cleanups for block cgroup Johannes Thumshirn
2020-04-30 15:03 ` [PATCH v2 1/3] block: remove blk_queue_root_blkg Johannes Thumshirn
2020-04-30 15:03 ` [PATCH v2 2/3] block: move blkcg_bio_issue_check out of line Johannes Thumshirn
2020-04-30 15:03 ` [PATCH v2 3/3] block: open-code blkg_path in it's sole caller Johannes Thumshirn
2020-05-04 15:31 ` [PATCH v2 0/3] block: drive-by cleanups for block cgroup Johannes Thumshirn
2020-05-08 10:33 ` Johannes Thumshirn

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