On 1/08/23 11:13, Yunlong Xing wrote:
> From: Yibin Ding <yibin.ding@xxxxxxxxxx>
>
> For a completed request, after the mmc_blk_mq_complete_rq(mq, req)
> function is executed, the bitmap_tags corresponding to the
> request will be cleared, that is, the request will be regarded as
> idle. If the request is acquired by a different type of process at
> this time, the issue_type of the request may change. It further
> caused the value of mq->in_flight[issue_type] to be abnormal,
> and a large number of requests could not be sent.
>
> p1: p2:
> mmc_blk_mq_complete_rq
> blk_mq_free_request
> blk_mq_get_request
> blk_mq_rq_ctx_init
> mmc_blk_mq_dec_in_flight
> mmc_issue_type(mq, req)
>
> This strategy can ensure the consistency of issue_type
> before and after executing mmc_blk_mq_complete_rq.
>
> Signed-off-by: Yibin Ding <yibin.ding@xxxxxxxxxx>
One cosmetic comment below, otherwise:
Fixes: 81196976ed94 ("mmc: block: Add blk-mq support")
Cc: stable@xxxxxxxxxxxxxxx
Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Thank you!
> ---
> drivers/mmc/core/block.c | 7 ++++---
> 1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
> index f701efb1fa78..5b750311f638 100644
> --- a/drivers/mmc/core/block.c
> +++ b/drivers/mmc/core/block.c
> @@ -2097,14 +2097,14 @@ static void mmc_blk_mq_poll_completion(struct mmc_queue *mq,
> mmc_blk_urgent_bkops(mq, mqrq);
> }
>
> -static void mmc_blk_mq_dec_in_flight(struct mmc_queue *mq, struct request *req)
> +static void mmc_blk_mq_dec_in_flight(struct mmc_queue *mq, enum mmc_issue_type issue_type)
> {
> unsigned long flags;
> bool put_card;
>
> spin_lock_irqsave(&mq->lock, flags);
>
> - mq->in_flight[mmc_issue_type(mq, req)] -= 1;
> + mq->in_flight[issue_type] -= 1;
>
> put_card = (mmc_tot_in_flight(mq) == 0);
>
> @@ -2120,6 +2120,7 @@ static void mmc_blk_mq_post_req(struct mmc_queue *mq, struct request *req,
> struct mmc_queue_req *mqrq = req_to_mmc_queue_req(req);
> struct mmc_request *mrq = &mqrq->brq.mrq;
> struct mmc_host *host = mq->card->host;
> + enum mmc_issue_type issue_type = mmc_issue_type(mq, req);
It looks slightly neater to put the local declarations in
descending order of line length if possible e.g.
+ enum mmc_issue_type issue_type = mmc_issue_type(mq, req);
struct mmc_queue_req *mqrq = req_to_mmc_queue_req(req);
struct mmc_request *mrq = &mqrq->brq.mrq;
struct mmc_host *host = mq->card->host;
>
> mmc_post_req(host, mrq, 0);
>
> @@ -2136,7 +2137,7 @@ static void mmc_blk_mq_post_req(struct mmc_queue *mq, struct request *req,
> blk_mq_complete_request(req);
> }
>
> - mmc_blk_mq_dec_in_flight(mq, req);
> + mmc_blk_mq_dec_in_flight(mq, issue_type);
> }
>
> void mmc_blk_mq_recovery(struct mmc_queue *mq)
