* [PATCH, RESEND 0/2] Simplify blk-mq implementation
@ 2019-07-01 15:47 Bart Van Assche
2019-07-01 15:47 ` [PATCH 1/2] blk-mq: Remove blk_mq_put_ctx() Bart Van Assche
` (2 more replies)
0 siblings, 3 replies; 11+ messages in thread
From: Bart Van Assche @ 2019-07-01 15:47 UTC (permalink / raw)
To: Jens Axboe; +Cc: linux-block, Christoph Hellwig, Bart Van Assche
Hi Jens,
While reviewing the blk_mq_make_request() code I noticed that it is possible
to simplify the implementation of that function. Please consider these patches
for kernel v5.3.
Thanks,
Bart.
Bart Van Assche (2):
blk-mq: Remove blk_mq_put_ctx()
blk-mq: Simplify blk_mq_make_request()
block/blk-mq-sched.c | 5 +----
block/blk-mq-tag.c | 8 --------
block/blk-mq.c | 26 +++++---------------------
block/blk-mq.h | 7 +------
block/kyber-iosched.c | 1 -
5 files changed, 7 insertions(+), 40 deletions(-)
--
2.22.0.410.gd8fdbe21b5-goog
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH 1/2] blk-mq: Remove blk_mq_put_ctx()
2019-07-01 15:47 [PATCH, RESEND 0/2] Simplify blk-mq implementation Bart Van Assche
@ 2019-07-01 15:47 ` Bart Van Assche
2019-07-02 13:25 ` Christoph Hellwig
2019-07-03 2:45 ` Ming Lei
2019-07-01 15:47 ` [PATCH 2/2] blk-mq: Simplify blk_mq_make_request() Bart Van Assche
2019-07-03 2:34 ` [PATCH, RESEND 0/2] Simplify blk-mq implementation Jens Axboe
2 siblings, 2 replies; 11+ messages in thread
From: Bart Van Assche @ 2019-07-01 15:47 UTC (permalink / raw)
To: Jens Axboe
Cc: linux-block, Christoph Hellwig, Bart Van Assche,
Christoph Hellwig, Ming Lei, Hannes Reinecke, Omar Sandoval
No code that occurs between blk_mq_get_ctx() and blk_mq_put_ctx() depends
on preemption being disabled for its correctness. Since removing the CPU
preemption calls does not measurably affect performance, simplify the
blk-mq code by removing the blk_mq_put_ctx() function and also by not
disabling preemption in blk_mq_get_ctx().
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
---
block/blk-mq-sched.c | 5 +----
block/blk-mq-tag.c | 8 --------
block/blk-mq.c | 16 +++-------------
block/blk-mq.h | 7 +------
block/kyber-iosched.c | 1 -
5 files changed, 5 insertions(+), 32 deletions(-)
diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c
index 956a7aa9a637..c9d183d6c499 100644
--- a/block/blk-mq-sched.c
+++ b/block/blk-mq-sched.c
@@ -330,10 +330,8 @@ bool __blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio,
bool ret = false;
enum hctx_type type;
- if (e && e->type->ops.bio_merge) {
- blk_mq_put_ctx(ctx);
+ if (e && e->type->ops.bio_merge)
return e->type->ops.bio_merge(hctx, bio, nr_segs);
- }
type = hctx->type;
if ((hctx->flags & BLK_MQ_F_SHOULD_MERGE) &&
@@ -344,7 +342,6 @@ bool __blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio,
spin_unlock(&ctx->lock);
}
- blk_mq_put_ctx(ctx);
return ret;
}
diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
index 7513c8eaabee..da19f0bc8876 100644
--- a/block/blk-mq-tag.c
+++ b/block/blk-mq-tag.c
@@ -113,7 +113,6 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
struct sbq_wait_state *ws;
DEFINE_SBQ_WAIT(wait);
unsigned int tag_offset;
- bool drop_ctx;
int tag;
if (data->flags & BLK_MQ_REQ_RESERVED) {
@@ -136,7 +135,6 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
return BLK_MQ_TAG_FAIL;
ws = bt_wait_ptr(bt, data->hctx);
- drop_ctx = data->ctx == NULL;
do {
struct sbitmap_queue *bt_prev;
@@ -161,9 +159,6 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
if (tag != -1)
break;
- if (data->ctx)
- blk_mq_put_ctx(data->ctx);
-
bt_prev = bt;
io_schedule();
@@ -189,9 +184,6 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
ws = bt_wait_ptr(bt, data->hctx);
} while (1);
- if (drop_ctx && data->ctx)
- blk_mq_put_ctx(data->ctx);
-
sbitmap_finish_wait(bt, ws, &wait);
found_tag:
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 2f0b14d2ecdc..4d661545ad1d 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -359,13 +359,13 @@ static struct request *blk_mq_get_request(struct request_queue *q,
struct elevator_queue *e = q->elevator;
struct request *rq;
unsigned int tag;
- bool put_ctx_on_error = false;
+ bool clear_ctx_on_error = false;
blk_queue_enter_live(q);
data->q = q;
if (likely(!data->ctx)) {
data->ctx = blk_mq_get_ctx(q);
- put_ctx_on_error = true;
+ clear_ctx_on_error = true;
}
if (likely(!data->hctx))
data->hctx = blk_mq_map_queue(q, data->cmd_flags,
@@ -391,10 +391,8 @@ static struct request *blk_mq_get_request(struct request_queue *q,
tag = blk_mq_get_tag(data);
if (tag == BLK_MQ_TAG_FAIL) {
- if (put_ctx_on_error) {
- blk_mq_put_ctx(data->ctx);
+ if (clear_ctx_on_error)
data->ctx = NULL;
- }
blk_queue_exit(q);
return NULL;
}
@@ -431,8 +429,6 @@ struct request *blk_mq_alloc_request(struct request_queue *q, unsigned int op,
if (!rq)
return ERR_PTR(-EWOULDBLOCK);
- blk_mq_put_ctx(alloc_data.ctx);
-
rq->__data_len = 0;
rq->__sector = (sector_t) -1;
rq->bio = rq->biotail = NULL;
@@ -1981,7 +1977,6 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
plug = current->plug;
if (unlikely(is_flush_fua)) {
- blk_mq_put_ctx(data.ctx);
blk_mq_bio_to_request(rq, bio, nr_segs);
/* bypass scheduler for flush rq */
@@ -1995,7 +1990,6 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
unsigned int request_count = plug->rq_count;
struct request *last = NULL;
- blk_mq_put_ctx(data.ctx);
blk_mq_bio_to_request(rq, bio, nr_segs);
if (!request_count)
@@ -2029,8 +2023,6 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
blk_add_rq_to_plug(plug, rq);
trace_block_plug(q);
- blk_mq_put_ctx(data.ctx);
-
if (same_queue_rq) {
data.hctx = same_queue_rq->mq_hctx;
trace_block_unplug(q, 1, true);
@@ -2039,11 +2031,9 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
}
} else if ((q->nr_hw_queues > 1 && is_sync) || (!q->elevator &&
!data.hctx->dispatch_busy)) {
- blk_mq_put_ctx(data.ctx);
blk_mq_bio_to_request(rq, bio, nr_segs);
blk_mq_try_issue_directly(data.hctx, rq, &cookie);
} else {
- blk_mq_put_ctx(data.ctx);
blk_mq_bio_to_request(rq, bio, nr_segs);
blk_mq_sched_insert_request(rq, false, true, true);
}
diff --git a/block/blk-mq.h b/block/blk-mq.h
index 633a5a77ee8b..f4bf5161333e 100644
--- a/block/blk-mq.h
+++ b/block/blk-mq.h
@@ -151,12 +151,7 @@ static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q,
*/
static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
{
- return __blk_mq_get_ctx(q, get_cpu());
-}
-
-static inline void blk_mq_put_ctx(struct blk_mq_ctx *ctx)
-{
- put_cpu();
+ return __blk_mq_get_ctx(q, raw_smp_processor_id());
}
struct blk_mq_alloc_data {
diff --git a/block/kyber-iosched.c b/block/kyber-iosched.c
index 3c2602601741..34dcea0ef637 100644
--- a/block/kyber-iosched.c
+++ b/block/kyber-iosched.c
@@ -575,7 +575,6 @@ static bool kyber_bio_merge(struct blk_mq_hw_ctx *hctx, struct bio *bio,
spin_lock(&kcq->lock);
merged = blk_mq_bio_list_merge(hctx->queue, rq_list, bio, nr_segs);
spin_unlock(&kcq->lock);
- blk_mq_put_ctx(ctx);
return merged;
}
--
2.22.0.410.gd8fdbe21b5-goog
^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH 2/2] blk-mq: Simplify blk_mq_make_request()
2019-07-01 15:47 [PATCH, RESEND 0/2] Simplify blk-mq implementation Bart Van Assche
2019-07-01 15:47 ` [PATCH 1/2] blk-mq: Remove blk_mq_put_ctx() Bart Van Assche
@ 2019-07-01 15:47 ` Bart Van Assche
2019-07-02 13:26 ` Christoph Hellwig
` (2 more replies)
2019-07-03 2:34 ` [PATCH, RESEND 0/2] Simplify blk-mq implementation Jens Axboe
2 siblings, 3 replies; 11+ messages in thread
From: Bart Van Assche @ 2019-07-01 15:47 UTC (permalink / raw)
To: Jens Axboe
Cc: linux-block, Christoph Hellwig, Bart Van Assche,
Christoph Hellwig, Ming Lei, Hannes Reinecke, Omar Sandoval
Move the blk_mq_bio_to_request() call in front of the if-statement.
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
---
block/blk-mq.c | 10 ++--------
1 file changed, 2 insertions(+), 8 deletions(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 4d661545ad1d..0fa03f524541 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1975,10 +1975,10 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
cookie = request_to_qc_t(data.hctx, rq);
+ blk_mq_bio_to_request(rq, bio, nr_segs);
+
plug = current->plug;
if (unlikely(is_flush_fua)) {
- blk_mq_bio_to_request(rq, bio, nr_segs);
-
/* bypass scheduler for flush rq */
blk_insert_flush(rq);
blk_mq_run_hw_queue(data.hctx, true);
@@ -1990,8 +1990,6 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
unsigned int request_count = plug->rq_count;
struct request *last = NULL;
- blk_mq_bio_to_request(rq, bio, nr_segs);
-
if (!request_count)
trace_block_plug(q);
else
@@ -2005,8 +2003,6 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
blk_add_rq_to_plug(plug, rq);
} else if (plug && !blk_queue_nomerges(q)) {
- blk_mq_bio_to_request(rq, bio, nr_segs);
-
/*
* We do limited plugging. If the bio can be merged, do that.
* Otherwise the existing request in the plug list will be
@@ -2031,10 +2027,8 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
}
} else if ((q->nr_hw_queues > 1 && is_sync) || (!q->elevator &&
!data.hctx->dispatch_busy)) {
- blk_mq_bio_to_request(rq, bio, nr_segs);
blk_mq_try_issue_directly(data.hctx, rq, &cookie);
} else {
- blk_mq_bio_to_request(rq, bio, nr_segs);
blk_mq_sched_insert_request(rq, false, true, true);
}
--
2.22.0.410.gd8fdbe21b5-goog
^ permalink raw reply related [flat|nested] 11+ messages in thread
* Re: [PATCH 1/2] blk-mq: Remove blk_mq_put_ctx()
2019-07-01 15:47 ` [PATCH 1/2] blk-mq: Remove blk_mq_put_ctx() Bart Van Assche
@ 2019-07-02 13:25 ` Christoph Hellwig
2019-07-02 13:25 ` Christoph Hellwig
2019-07-03 2:45 ` Ming Lei
1 sibling, 1 reply; 11+ messages in thread
From: Christoph Hellwig @ 2019-07-02 13:25 UTC (permalink / raw)
To: Bart Van Assche
Cc: Jens Axboe, linux-block, Christoph Hellwig, Christoph Hellwig,
Ming Lei, Hannes Reinecke, Omar Sandoval
On Mon, Jul 01, 2019 at 08:47:29AM -0700, Bart Van Assche wrote:
> No code that occurs between blk_mq_get_ctx() and blk_mq_put_ctx() depends
> on preemption being disabled for its correctness. Since removing the CPU
> preemption calls does not measurably affect performance, simplify the
> blk-mq code by removing the blk_mq_put_ctx() function and also by not
> disabling preemption in blk_mq_get_ctx().
Looks good,
Reviewed-by: Christoph Hellwig <hch@lst.de>
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH 1/2] blk-mq: Remove blk_mq_put_ctx()
2019-07-02 13:25 ` Christoph Hellwig
@ 2019-07-02 13:25 ` Christoph Hellwig
0 siblings, 0 replies; 11+ messages in thread
From: Christoph Hellwig @ 2019-07-02 13:25 UTC (permalink / raw)
To: Bart Van Assche
Cc: Jens Axboe, linux-block, Christoph Hellwig, Christoph Hellwig,
Ming Lei, Hannes Reinecke, Omar Sandoval
On Tue, Jul 02, 2019 at 03:25:44PM +0200, Christoph Hellwig wrote:
> On Mon, Jul 01, 2019 at 08:47:29AM -0700, Bart Van Assche wrote:
> > No code that occurs between blk_mq_get_ctx() and blk_mq_put_ctx() depends
> > on preemption being disabled for its correctness. Since removing the CPU
> > preemption calls does not measurably affect performance, simplify the
> > blk-mq code by removing the blk_mq_put_ctx() function and also by not
> > disabling preemption in blk_mq_get_ctx().
>
> Looks good,
>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
Looks good,
Reviewed-by: Christoph Hellwig <hch@lst.de>
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH 2/2] blk-mq: Simplify blk_mq_make_request()
2019-07-01 15:47 ` [PATCH 2/2] blk-mq: Simplify blk_mq_make_request() Bart Van Assche
@ 2019-07-02 13:26 ` Christoph Hellwig
2019-07-02 23:42 ` Minwoo Im
2019-07-03 2:46 ` Ming Lei
2 siblings, 0 replies; 11+ messages in thread
From: Christoph Hellwig @ 2019-07-02 13:26 UTC (permalink / raw)
To: Bart Van Assche
Cc: Jens Axboe, linux-block, Christoph Hellwig, Christoph Hellwig,
Ming Lei, Hannes Reinecke, Omar Sandoval
On Mon, Jul 01, 2019 at 08:47:30AM -0700, Bart Van Assche wrote:
> Move the blk_mq_bio_to_request() call in front of the if-statement.
Looks good:
Reviewed-by: Christoph Hellwig <hch@lst.de>
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH 2/2] blk-mq: Simplify blk_mq_make_request()
2019-07-01 15:47 ` [PATCH 2/2] blk-mq: Simplify blk_mq_make_request() Bart Van Assche
2019-07-02 13:26 ` Christoph Hellwig
@ 2019-07-02 23:42 ` Minwoo Im
2019-07-03 2:46 ` Ming Lei
2 siblings, 0 replies; 11+ messages in thread
From: Minwoo Im @ 2019-07-02 23:42 UTC (permalink / raw)
To: Bart Van Assche
Cc: Jens Axboe, linux-block, Christoph Hellwig, Christoph Hellwig,
Ming Lei, Hannes Reinecke, Omar Sandoval, Minwoo Im
On 19-07-01 08:47:30, Bart Van Assche wrote:
> Move the blk_mq_bio_to_request() call in front of the if-statement.
This looks good to me based on the first patch.
Reviewed-by: Minwoo Im <minwoo.im.dev@gmail.com>
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH, RESEND 0/2] Simplify blk-mq implementation
2019-07-01 15:47 [PATCH, RESEND 0/2] Simplify blk-mq implementation Bart Van Assche
2019-07-01 15:47 ` [PATCH 1/2] blk-mq: Remove blk_mq_put_ctx() Bart Van Assche
2019-07-01 15:47 ` [PATCH 2/2] blk-mq: Simplify blk_mq_make_request() Bart Van Assche
@ 2019-07-03 2:34 ` Jens Axboe
2 siblings, 0 replies; 11+ messages in thread
From: Jens Axboe @ 2019-07-03 2:34 UTC (permalink / raw)
To: Bart Van Assche; +Cc: linux-block, Christoph Hellwig
On 7/1/19 9:47 AM, Bart Van Assche wrote:
> Hi Jens,
>
> While reviewing the blk_mq_make_request() code I noticed that it is possible
> to simplify the implementation of that function. Please consider these patches
> for kernel v5.3.
Applied, thanks Bart.
--
Jens Axboe
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH 1/2] blk-mq: Remove blk_mq_put_ctx()
2019-07-01 15:47 ` [PATCH 1/2] blk-mq: Remove blk_mq_put_ctx() Bart Van Assche
2019-07-02 13:25 ` Christoph Hellwig
@ 2019-07-03 2:45 ` Ming Lei
2019-07-03 15:06 ` Bart Van Assche
1 sibling, 1 reply; 11+ messages in thread
From: Ming Lei @ 2019-07-03 2:45 UTC (permalink / raw)
To: Bart Van Assche
Cc: Jens Axboe, linux-block, Christoph Hellwig, Christoph Hellwig,
Hannes Reinecke, Omar Sandoval
On Mon, Jul 01, 2019 at 08:47:29AM -0700, Bart Van Assche wrote:
> No code that occurs between blk_mq_get_ctx() and blk_mq_put_ctx() depends
> on preemption being disabled for its correctness. Since removing the CPU
> preemption calls does not measurably affect performance, simplify the
> blk-mq code by removing the blk_mq_put_ctx() function and also by not
> disabling preemption in blk_mq_get_ctx().
>
> Cc: Christoph Hellwig <hch@infradead.org>
> Cc: Ming Lei <ming.lei@redhat.com>
> Cc: Hannes Reinecke <hare@suse.com>
> Cc: Omar Sandoval <osandov@fb.com>
> Signed-off-by: Bart Van Assche <bvanassche@acm.org>
> ---
> block/blk-mq-sched.c | 5 +----
> block/blk-mq-tag.c | 8 --------
> block/blk-mq.c | 16 +++-------------
> block/blk-mq.h | 7 +------
> block/kyber-iosched.c | 1 -
> 5 files changed, 5 insertions(+), 32 deletions(-)
>
> diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c
> index 956a7aa9a637..c9d183d6c499 100644
> --- a/block/blk-mq-sched.c
> +++ b/block/blk-mq-sched.c
> @@ -330,10 +330,8 @@ bool __blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio,
> bool ret = false;
> enum hctx_type type;
>
> - if (e && e->type->ops.bio_merge) {
> - blk_mq_put_ctx(ctx);
> + if (e && e->type->ops.bio_merge)
> return e->type->ops.bio_merge(hctx, bio, nr_segs);
> - }
>
> type = hctx->type;
> if ((hctx->flags & BLK_MQ_F_SHOULD_MERGE) &&
> @@ -344,7 +342,6 @@ bool __blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio,
> spin_unlock(&ctx->lock);
> }
>
> - blk_mq_put_ctx(ctx);
> return ret;
> }
>
> diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
> index 7513c8eaabee..da19f0bc8876 100644
> --- a/block/blk-mq-tag.c
> +++ b/block/blk-mq-tag.c
> @@ -113,7 +113,6 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
> struct sbq_wait_state *ws;
> DEFINE_SBQ_WAIT(wait);
> unsigned int tag_offset;
> - bool drop_ctx;
> int tag;
>
> if (data->flags & BLK_MQ_REQ_RESERVED) {
> @@ -136,7 +135,6 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
> return BLK_MQ_TAG_FAIL;
>
> ws = bt_wait_ptr(bt, data->hctx);
> - drop_ctx = data->ctx == NULL;
> do {
> struct sbitmap_queue *bt_prev;
>
> @@ -161,9 +159,6 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
> if (tag != -1)
> break;
>
> - if (data->ctx)
> - blk_mq_put_ctx(data->ctx);
> -
> bt_prev = bt;
> io_schedule();
>
> @@ -189,9 +184,6 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
> ws = bt_wait_ptr(bt, data->hctx);
> } while (1);
>
> - if (drop_ctx && data->ctx)
> - blk_mq_put_ctx(data->ctx);
> -
> sbitmap_finish_wait(bt, ws, &wait);
>
> found_tag:
> diff --git a/block/blk-mq.c b/block/blk-mq.c
> index 2f0b14d2ecdc..4d661545ad1d 100644
> --- a/block/blk-mq.c
> +++ b/block/blk-mq.c
> @@ -359,13 +359,13 @@ static struct request *blk_mq_get_request(struct request_queue *q,
> struct elevator_queue *e = q->elevator;
> struct request *rq;
> unsigned int tag;
> - bool put_ctx_on_error = false;
> + bool clear_ctx_on_error = false;
>
> blk_queue_enter_live(q);
> data->q = q;
> if (likely(!data->ctx)) {
> data->ctx = blk_mq_get_ctx(q);
> - put_ctx_on_error = true;
> + clear_ctx_on_error = true;
> }
> if (likely(!data->hctx))
> data->hctx = blk_mq_map_queue(q, data->cmd_flags,
> @@ -391,10 +391,8 @@ static struct request *blk_mq_get_request(struct request_queue *q,
>
> tag = blk_mq_get_tag(data);
> if (tag == BLK_MQ_TAG_FAIL) {
> - if (put_ctx_on_error) {
> - blk_mq_put_ctx(data->ctx);
> + if (clear_ctx_on_error)
> data->ctx = NULL;
> - }
> blk_queue_exit(q);
> return NULL;
> }
> @@ -431,8 +429,6 @@ struct request *blk_mq_alloc_request(struct request_queue *q, unsigned int op,
> if (!rq)
> return ERR_PTR(-EWOULDBLOCK);
>
> - blk_mq_put_ctx(alloc_data.ctx);
> -
> rq->__data_len = 0;
> rq->__sector = (sector_t) -1;
> rq->bio = rq->biotail = NULL;
> @@ -1981,7 +1977,6 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
>
> plug = current->plug;
> if (unlikely(is_flush_fua)) {
> - blk_mq_put_ctx(data.ctx);
> blk_mq_bio_to_request(rq, bio, nr_segs);
>
> /* bypass scheduler for flush rq */
> @@ -1995,7 +1990,6 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
> unsigned int request_count = plug->rq_count;
> struct request *last = NULL;
>
> - blk_mq_put_ctx(data.ctx);
> blk_mq_bio_to_request(rq, bio, nr_segs);
>
> if (!request_count)
> @@ -2029,8 +2023,6 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
> blk_add_rq_to_plug(plug, rq);
> trace_block_plug(q);
>
> - blk_mq_put_ctx(data.ctx);
> -
> if (same_queue_rq) {
> data.hctx = same_queue_rq->mq_hctx;
> trace_block_unplug(q, 1, true);
> @@ -2039,11 +2031,9 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
> }
> } else if ((q->nr_hw_queues > 1 && is_sync) || (!q->elevator &&
> !data.hctx->dispatch_busy)) {
> - blk_mq_put_ctx(data.ctx);
> blk_mq_bio_to_request(rq, bio, nr_segs);
> blk_mq_try_issue_directly(data.hctx, rq, &cookie);
> } else {
> - blk_mq_put_ctx(data.ctx);
> blk_mq_bio_to_request(rq, bio, nr_segs);
> blk_mq_sched_insert_request(rq, false, true, true);
> }
> diff --git a/block/blk-mq.h b/block/blk-mq.h
> index 633a5a77ee8b..f4bf5161333e 100644
> --- a/block/blk-mq.h
> +++ b/block/blk-mq.h
> @@ -151,12 +151,7 @@ static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q,
> */
> static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
> {
> - return __blk_mq_get_ctx(q, get_cpu());
> -}
> -
> -static inline void blk_mq_put_ctx(struct blk_mq_ctx *ctx)
> -{
> - put_cpu();
> + return __blk_mq_get_ctx(q, raw_smp_processor_id());
> }
Then there isn't any difference between __blk_mq_get_ctx() and blk_mq_get_ctx(),
so could you kill __blk_mq_get_ctx()?
Otherwise, looks fine:
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Thanks,
Ming
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH 2/2] blk-mq: Simplify blk_mq_make_request()
2019-07-01 15:47 ` [PATCH 2/2] blk-mq: Simplify blk_mq_make_request() Bart Van Assche
2019-07-02 13:26 ` Christoph Hellwig
2019-07-02 23:42 ` Minwoo Im
@ 2019-07-03 2:46 ` Ming Lei
2 siblings, 0 replies; 11+ messages in thread
From: Ming Lei @ 2019-07-03 2:46 UTC (permalink / raw)
To: Bart Van Assche
Cc: Jens Axboe, linux-block, Christoph Hellwig, Christoph Hellwig,
Hannes Reinecke, Omar Sandoval
On Mon, Jul 01, 2019 at 08:47:30AM -0700, Bart Van Assche wrote:
> Move the blk_mq_bio_to_request() call in front of the if-statement.
>
> Cc: Christoph Hellwig <hch@infradead.org>
> Cc: Ming Lei <ming.lei@redhat.com>
> Cc: Hannes Reinecke <hare@suse.com>
> Cc: Omar Sandoval <osandov@fb.com>
> Signed-off-by: Bart Van Assche <bvanassche@acm.org>
> ---
> block/blk-mq.c | 10 ++--------
> 1 file changed, 2 insertions(+), 8 deletions(-)
>
> diff --git a/block/blk-mq.c b/block/blk-mq.c
> index 4d661545ad1d..0fa03f524541 100644
> --- a/block/blk-mq.c
> +++ b/block/blk-mq.c
> @@ -1975,10 +1975,10 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
>
> cookie = request_to_qc_t(data.hctx, rq);
>
> + blk_mq_bio_to_request(rq, bio, nr_segs);
> +
> plug = current->plug;
> if (unlikely(is_flush_fua)) {
> - blk_mq_bio_to_request(rq, bio, nr_segs);
> -
> /* bypass scheduler for flush rq */
> blk_insert_flush(rq);
> blk_mq_run_hw_queue(data.hctx, true);
> @@ -1990,8 +1990,6 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
> unsigned int request_count = plug->rq_count;
> struct request *last = NULL;
>
> - blk_mq_bio_to_request(rq, bio, nr_segs);
> -
> if (!request_count)
> trace_block_plug(q);
> else
> @@ -2005,8 +2003,6 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
>
> blk_add_rq_to_plug(plug, rq);
> } else if (plug && !blk_queue_nomerges(q)) {
> - blk_mq_bio_to_request(rq, bio, nr_segs);
> -
> /*
> * We do limited plugging. If the bio can be merged, do that.
> * Otherwise the existing request in the plug list will be
> @@ -2031,10 +2027,8 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
> }
> } else if ((q->nr_hw_queues > 1 && is_sync) || (!q->elevator &&
> !data.hctx->dispatch_busy)) {
> - blk_mq_bio_to_request(rq, bio, nr_segs);
> blk_mq_try_issue_directly(data.hctx, rq, &cookie);
> } else {
> - blk_mq_bio_to_request(rq, bio, nr_segs);
> blk_mq_sched_insert_request(rq, false, true, true);
> }
>
> --
> 2.22.0.410.gd8fdbe21b5-goog
>
Looks fine:
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Thanks,
Ming
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH 1/2] blk-mq: Remove blk_mq_put_ctx()
2019-07-03 2:45 ` Ming Lei
@ 2019-07-03 15:06 ` Bart Van Assche
0 siblings, 0 replies; 11+ messages in thread
From: Bart Van Assche @ 2019-07-03 15:06 UTC (permalink / raw)
To: Ming Lei
Cc: Jens Axboe, linux-block, Christoph Hellwig, Christoph Hellwig,
Hannes Reinecke, Omar Sandoval
On 7/2/19 7:45 PM, Ming Lei wrote:
> Then there isn't any difference between __blk_mq_get_ctx() and blk_mq_get_ctx(),
> so could you kill __blk_mq_get_ctx()?
I will post a patch that does this unless someone else does this before me.
Bart.
^ permalink raw reply [flat|nested] 11+ messages in thread
end of thread, other threads:[~2019-07-03 15:06 UTC | newest]
Thread overview: 11+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-07-01 15:47 [PATCH, RESEND 0/2] Simplify blk-mq implementation Bart Van Assche
2019-07-01 15:47 ` [PATCH 1/2] blk-mq: Remove blk_mq_put_ctx() Bart Van Assche
2019-07-02 13:25 ` Christoph Hellwig
2019-07-02 13:25 ` Christoph Hellwig
2019-07-03 2:45 ` Ming Lei
2019-07-03 15:06 ` Bart Van Assche
2019-07-01 15:47 ` [PATCH 2/2] blk-mq: Simplify blk_mq_make_request() Bart Van Assche
2019-07-02 13:26 ` Christoph Hellwig
2019-07-02 23:42 ` Minwoo Im
2019-07-03 2:46 ` Ming Lei
2019-07-03 2:34 ` [PATCH, RESEND 0/2] Simplify blk-mq implementation Jens Axboe
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).