2021-11-02 11:35:08

by John Garry

Subject: [PATCH RFT 1/3] blk-mq: Drop busy_iter_fn blk_mq_hw_ctx argument

The only user of blk_mq_hw_ctx blk_mq_hw_ctx argument is
blk_mq_rq_inflight().

Function blk_mq_rq_inflight() uses the hctx to find the associated request
queue to match against the request. However this same check is already
done in caller bt_iter(), so drop this check.

With that change there are no more users of busy_iter_fn blk_mq_hw_ctx
argument, so drop the argument.

Signed-off-by: John Garry <[email protected]>
---
block/blk-mq-tag.c | 2 +-
block/blk-mq.c | 17 ++++++++---------
include/linux/blk-mq.h | 3 +--
3 files changed, 10 insertions(+), 12 deletions(-)

diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
index 995336abee33..0d773c44a7ec 100644
--- a/block/blk-mq-tag.c
+++ b/block/blk-mq-tag.c
@@ -254,7 +254,7 @@ static bool bt_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data)
return true;

if (rq->q == hctx->queue && rq->mq_hctx == hctx)
- ret = iter_data->fn(hctx, rq, iter_data->data, reserved);
+ ret = iter_data->fn(rq, iter_data->data, reserved);
blk_mq_put_rq_ref(rq);
return ret;
}
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 07eb1412760b..c26e6c9301dd 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -126,8 +126,7 @@ struct mq_inflight {
unsigned int inflight[2];
};

-static bool blk_mq_check_inflight(struct blk_mq_hw_ctx *hctx,
- struct request *rq, void *priv,
+static bool blk_mq_check_inflight(struct request *rq, void *priv,
bool reserved)
{
struct mq_inflight *mi = priv;
@@ -1136,14 +1135,15 @@ void blk_mq_delay_kick_requeue_list(struct request_queue *q,
}
EXPORT_SYMBOL(blk_mq_delay_kick_requeue_list);

-static bool blk_mq_rq_inflight(struct blk_mq_hw_ctx *hctx, struct request *rq,
- void *priv, bool reserved)
+static bool blk_mq_rq_inflight(struct request *rq, void *priv,
+ bool reserved)
{
/*
- * If we find a request that isn't idle and the queue matches,
- * we know the queue is busy. Return false to stop the iteration.
+ * If we find a request that isn't idle we know the queue is busy
+ * as it's checked in the iter.
+ * Return false to stop the iteration.
*/
- if (blk_mq_request_started(rq) && rq->q == hctx->queue) {
+ if (blk_mq_request_started(rq)) {
bool *busy = priv;

*busy = true;
@@ -1205,8 +1205,7 @@ void blk_mq_put_rq_ref(struct request *rq)
__blk_mq_free_request(rq);
}

-static bool blk_mq_check_expired(struct blk_mq_hw_ctx *hctx,
- struct request *rq, void *priv, bool reserved)
+static bool blk_mq_check_expired(struct request *rq, void *priv, bool reserved)
{
unsigned long *next = priv;

diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index 8682663e7368..da8de0d6f99b 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -479,8 +479,7 @@ struct blk_mq_queue_data {
bool last;
};

-typedef bool (busy_iter_fn)(struct blk_mq_hw_ctx *, struct request *, void *,
- bool);
+typedef bool (busy_iter_fn)(struct request *, void *, bool);
typedef bool (busy_tag_iter_fn)(struct request *, void *, bool);

/**
--
2.17.1

2021-11-09 12:48:07

by Ming Lei

Subject: Re: [PATCH RFT 1/3] blk-mq: Drop busy_iter_fn blk_mq_hw_ctx argument

On Tue, Nov 02, 2021 at 07:27:33PM +0800, John Garry wrote:
> The only user of blk_mq_hw_ctx blk_mq_hw_ctx argument is
> blk_mq_rq_inflight().
>
> Function blk_mq_rq_inflight() uses the hctx to find the associated request
> queue to match against the request. However this same check is already
> done in caller bt_iter(), so drop this check.
>
> With that change there are no more users of busy_iter_fn blk_mq_hw_ctx
> argument, so drop the argument.
>
> Signed-off-by: John Garry <[email protected]>
> ---

Reviewed-by: Ming Lei <[email protected]>

--
Ming

2021-11-28 10:42:06

by Hannes Reinecke

Subject: Re: [PATCH RFT 1/3] blk-mq: Drop busy_iter_fn blk_mq_hw_ctx argument

On 11/2/21 12:27 PM, John Garry wrote:
> The only user of blk_mq_hw_ctx blk_mq_hw_ctx argument is
> blk_mq_rq_inflight().
>
> Function blk_mq_rq_inflight() uses the hctx to find the associated request
> queue to match against the request. However this same check is already
> done in caller bt_iter(), so drop this check.
>
> With that change there are no more users of busy_iter_fn blk_mq_hw_ctx
> argument, so drop the argument.
>
> Signed-off-by: John Garry <[email protected]>
> ---
> block/blk-mq-tag.c | 2 +-
> block/blk-mq.c | 17 ++++++++---------
> include/linux/blk-mq.h | 3 +--
> 3 files changed, 10 insertions(+), 12 deletions(-)
>
Reviewed-by Hannes Reinecke <[email protected]>

Cheers,

Hannes
--
Dr. Hannes Reinecke Kernel Storage Architect
[email protected] +49 911 74053 688
SUSE Software Solutions GmbH, Maxfeldstr. 5, 90409 Nürnberg
HRB 36809 (AG Nürnberg), Geschäftsführer: Felix Imendörffer