diff mbox series

[4/9] blk-mq: Add blk_mq_tag_resize_sched_shared_sbitmap()

Message ID 1626275195-215652-5-git-send-email-john.garry@huawei.com (mailing list archive)
State New, archived
Headers show
Series blk-mq: Reduce static requests memory footprint for shared sbitmap | expand

Commit Message

John Garry July 14, 2021, 3:06 p.m. UTC
Put the functionality to resize the sched shared sbitmap in a common
function.

Since the same formula is always used to resize, and it can be got from
the request queue argument, so just pass the request queue pointer.

Signed-off-by: John Garry <john.garry@huawei.com>
---
 block/blk-mq-sched.c |  3 +--
 block/blk-mq-tag.c   | 10 ++++++++++
 block/blk-mq-tag.h   |  1 +
 block/blk-mq.c       |  3 +--
 4 files changed, 13 insertions(+), 4 deletions(-)

Comments

Ming Lei July 20, 2021, 7:57 a.m. UTC | #1
On Wed, Jul 14, 2021 at 11:06:30PM +0800, John Garry wrote:
> Put the functionality to resize the sched shared sbitmap in a common
> function.
> 
> Since the same formula is always used to resize, and it can be got from
> the request queue argument, so just pass the request queue pointer.
> 
> Signed-off-by: John Garry <john.garry@huawei.com>
> ---
>  block/blk-mq-sched.c |  3 +--
>  block/blk-mq-tag.c   | 10 ++++++++++
>  block/blk-mq-tag.h   |  1 +
>  block/blk-mq.c       |  3 +--
>  4 files changed, 13 insertions(+), 4 deletions(-)
> 
> diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c
> index f5cb2931c20d..1e028183557d 100644
> --- a/block/blk-mq-sched.c
> +++ b/block/blk-mq-sched.c
> @@ -584,8 +584,7 @@ static int blk_mq_init_sched_shared_sbitmap(struct request_queue *queue)
>  					&queue->sched_breserved_tags;
>  	}
>  
> -	sbitmap_queue_resize(&queue->sched_bitmap_tags,
> -			     queue->nr_requests - set->reserved_tags);
> +	blk_mq_tag_resize_sched_shared_sbitmap(queue);
>  
>  	return 0;
>  }
> diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
> index 86f87346232a..55c7f1bf41c7 100644
> --- a/block/blk-mq-tag.c
> +++ b/block/blk-mq-tag.c
> @@ -634,6 +634,16 @@ void blk_mq_tag_resize_shared_sbitmap(struct blk_mq_tag_set *set, unsigned int s
>  	sbitmap_queue_resize(&set->__bitmap_tags, size - set->reserved_tags);
>  }
>  
> +/*
> + * We always resize with q->nr_requests - q->tag_set->reserved_tags, so
> + * don't bother passing a size.
> + */
> +void blk_mq_tag_resize_sched_shared_sbitmap(struct request_queue *q)
> +{
> +	sbitmap_queue_resize(&q->sched_bitmap_tags,
> +			     q->nr_requests - q->tag_set->reserved_tags);
> +}

It is a bit hard to follow the resize part of the name, since no size
parameter passed in. Maybe update is better?
John Garry July 20, 2021, 8:08 a.m. UTC | #2
On 20/07/2021 08:57, Ming Lei wrote:
>> diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c
>> index f5cb2931c20d..1e028183557d 100644
>> --- a/block/blk-mq-sched.c
>> +++ b/block/blk-mq-sched.c
>> @@ -584,8 +584,7 @@ static int blk_mq_init_sched_shared_sbitmap(struct request_queue *queue)
>>   					&queue->sched_breserved_tags;
>>   	}
>>   
>> -	sbitmap_queue_resize(&queue->sched_bitmap_tags,
>> -			     queue->nr_requests - set->reserved_tags);
>> +	blk_mq_tag_resize_sched_shared_sbitmap(queue);
>>   
>>   	return 0;
>>   }
>> diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
>> index 86f87346232a..55c7f1bf41c7 100644
>> --- a/block/blk-mq-tag.c
>> +++ b/block/blk-mq-tag.c
>> @@ -634,6 +634,16 @@ void blk_mq_tag_resize_shared_sbitmap(struct blk_mq_tag_set *set, unsigned int s
>>   	sbitmap_queue_resize(&set->__bitmap_tags, size - set->reserved_tags);
>>   }
>>   
>> +/*
>> + * We always resize with q->nr_requests - q->tag_set->reserved_tags, so
>> + * don't bother passing a size.
>> + */
>> +void blk_mq_tag_resize_sched_shared_sbitmap(struct request_queue *q)
>> +{
>> +	sbitmap_queue_resize(&q->sched_bitmap_tags,
>> +			     q->nr_requests - q->tag_set->reserved_tags);
>> +}
> It is a bit hard to follow the resize part of the name, since no size
> parameter passed in. Maybe update is better?

Right, this function is a bit odd. Maybe I can just have a size argument 
for consistency with blk_mq_tag_resize_shared_sbitmap().

Thanks,
John
diff mbox series

Patch

diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c
index f5cb2931c20d..1e028183557d 100644
--- a/block/blk-mq-sched.c
+++ b/block/blk-mq-sched.c
@@ -584,8 +584,7 @@  static int blk_mq_init_sched_shared_sbitmap(struct request_queue *queue)
 					&queue->sched_breserved_tags;
 	}
 
-	sbitmap_queue_resize(&queue->sched_bitmap_tags,
-			     queue->nr_requests - set->reserved_tags);
+	blk_mq_tag_resize_sched_shared_sbitmap(queue);
 
 	return 0;
 }
diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
index 86f87346232a..55c7f1bf41c7 100644
--- a/block/blk-mq-tag.c
+++ b/block/blk-mq-tag.c
@@ -634,6 +634,16 @@  void blk_mq_tag_resize_shared_sbitmap(struct blk_mq_tag_set *set, unsigned int s
 	sbitmap_queue_resize(&set->__bitmap_tags, size - set->reserved_tags);
 }
 
+/*
+ * We always resize with q->nr_requests - q->tag_set->reserved_tags, so
+ * don't bother passing a size.
+ */
+void blk_mq_tag_resize_sched_shared_sbitmap(struct request_queue *q)
+{
+	sbitmap_queue_resize(&q->sched_bitmap_tags,
+			     q->nr_requests - q->tag_set->reserved_tags);
+}
+
 /**
  * blk_mq_unique_tag() - return a tag that is unique queue-wide
  * @rq: request for which to compute a unique tag
diff --git a/block/blk-mq-tag.h b/block/blk-mq-tag.h
index 8ed55af08427..3a7495e47fb4 100644
--- a/block/blk-mq-tag.h
+++ b/block/blk-mq-tag.h
@@ -48,6 +48,7 @@  extern int blk_mq_tag_update_depth(struct blk_mq_hw_ctx *hctx,
 					unsigned int depth, bool can_grow);
 extern void blk_mq_tag_resize_shared_sbitmap(struct blk_mq_tag_set *set,
 					     unsigned int size);
+extern void blk_mq_tag_resize_sched_shared_sbitmap(struct request_queue *q);
 
 extern void blk_mq_tag_wakeup_all(struct blk_mq_tags *tags, bool);
 void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn,
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 56e3c6fdba60..b0d4197d36c7 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -3643,8 +3643,7 @@  int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr)
 		q->nr_requests = nr;
 		if (blk_mq_is_sbitmap_shared(set->flags)) {
 			if (q->elevator) {
-				sbitmap_queue_resize(&q->sched_bitmap_tags,
-						     nr - set->reserved_tags);
+				blk_mq_tag_resize_sched_shared_sbitmap(q);
 			} else {
 				blk_mq_tag_resize_shared_sbitmap(set, nr);
 			}