diff mbox series

[RESEND,v3,08/13] blk-mq: Don't clear driver tags own mapping

Message ID 1631545950-56586-9-git-send-email-john.garry@huawei.com
State New
Headers show
Series blk-mq: Reduce static requests memory footprint for shared sbitmap | expand

Commit Message

John Garry Sept. 13, 2021, 3:12 p.m. UTC
Function blk_mq_clear_rq_mapping() is required to clear the sched tags
mappings in driver tags rqs[].

But there is no need for a driver tags to clear its own mapping, so skip
clearing the mapping in this scenario.

Signed-off-by: John Garry <john.garry@huawei.com>

---
 block/blk-mq.c | 4 ++++
 1 file changed, 4 insertions(+)

-- 
2.26.2

Comments

Hannes Reinecke Sept. 14, 2021, 5:45 a.m. UTC | #1
On 9/13/21 5:12 PM, John Garry wrote:
> Function blk_mq_clear_rq_mapping() is required to clear the sched tags

> mappings in driver tags rqs[].

> 

> But there is no need for a driver tags to clear its own mapping, so skip

> clearing the mapping in this scenario.

> 

> Signed-off-by: John Garry <john.garry@huawei.com>

> ---

>   block/blk-mq.c | 4 ++++

>   1 file changed, 4 insertions(+)

> 

> diff --git a/block/blk-mq.c b/block/blk-mq.c

> index 4bae8afdfbe1..5229c5420b85 100644

> --- a/block/blk-mq.c

> +++ b/block/blk-mq.c

> @@ -2308,6 +2308,10 @@ static void blk_mq_clear_rq_mapping(struct blk_mq_tags *drv_tags,

>   	struct page *page;

>   	unsigned long flags;

>   

> +	/* There is no need to clear a driver tags own mapping */

> +	if (drv_tags == tags)

> +		return;

> +

>   	list_for_each_entry(page, &tags->page_list, lru) {

>   		unsigned long start = (unsigned long)page_address(page);

>   		unsigned long end = start + order_to_size(page->private);

> 

Reviewed-by: Hannes Reinecke <hare@suse.de>


Cheers,

Hannes
-- 
Dr. Hannes Reinecke                Kernel Storage Architect
hare@suse.de                              +49 911 74053 688
SUSE Software Solutions GmbH, Maxfeldstr. 5, 90409 Nürnberg
HRB 36809 (AG Nürnberg), Geschäftsführer: Felix Imendörffer
diff mbox series

Patch

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 4bae8afdfbe1..5229c5420b85 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -2308,6 +2308,10 @@  static void blk_mq_clear_rq_mapping(struct blk_mq_tags *drv_tags,
 	struct page *page;
 	unsigned long flags;
 
+	/* There is no need to clear a driver tags own mapping */
+	if (drv_tags == tags)
+		return;
+
 	list_for_each_entry(page, &tags->page_list, lru) {
 		unsigned long start = (unsigned long)page_address(page);
 		unsigned long end = start + order_to_size(page->private);