diff mbox series

[RESEND,v3,01/13] blk-mq: Change rqs check in blk_mq_free_rqs()

Message ID 1631545950-56586-2-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 Sept. 13, 2021, 3:12 p.m. UTC
The original code in commit 24d2f90309b23 ("blk-mq: split out tag
initialization, support shared tags") would check tags->rqs is non-NULL and
then dereference tags->rqs[].

Then in commit 2af8cbe30531 ("blk-mq: split tag ->rqs[] into two"), we
started to dereference tags->static_rqs[], but continued to check non-NULL
tags->rqs.

Check tags->static_rqs as non-NULL instead, which is more logical.

Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
---
 block/blk-mq.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Hannes Reinecke Sept. 14, 2021, 5:35 a.m. UTC | #1
On 9/13/21 5:12 PM, John Garry wrote:
> The original code in commit 24d2f90309b23 ("blk-mq: split out tag
> initialization, support shared tags") would check tags->rqs is non-NULL and
> then dereference tags->rqs[].
> 
> Then in commit 2af8cbe30531 ("blk-mq: split tag ->rqs[] into two"), we
> started to dereference tags->static_rqs[], but continued to check non-NULL
> tags->rqs.
> 
> Check tags->static_rqs as non-NULL instead, which is more logical.
> 
> Signed-off-by: John Garry <john.garry@huawei.com>
> Reviewed-by: Ming Lei <ming.lei@redhat.com>
> ---
>   block/blk-mq.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/block/blk-mq.c b/block/blk-mq.c
> index 108a352051be..2316ff27c1f5 100644
> --- a/block/blk-mq.c
> +++ b/block/blk-mq.c
> @@ -2340,7 +2340,7 @@ void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
>   {
>   	struct page *page;
>   
> -	if (tags->rqs && set->ops->exit_request) {
> +	if (tags->static_rqs && set->ops->exit_request) {
>   		int i;
>   
>   		for (i = 0; i < tags->nr_tags; i++) {
> 
Reviewed-by: Hannes Reinecke <hare@suse.de>

Cheers,

Hannes
diff mbox series

Patch

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 108a352051be..2316ff27c1f5 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -2340,7 +2340,7 @@  void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
 {
 	struct page *page;
 
-	if (tags->rqs && set->ops->exit_request) {
+	if (tags->static_rqs && set->ops->exit_request) {
 		int i;
 
 		for (i = 0; i < tags->nr_tags; i++) {