Commit e7602bb4 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

block: remove BLK_MQ_F_NO_SCHED 



The only queues that really can't support a scheduler are those that
do not have a gendisk associated with them, and thus can't be used for
non-passthrough commands.  In addition to those null_blk can optionally
set the flag, which is a bad odd.  Replace the null_blk usage with
BLK_MQ_F_NO_SCHED_BY_DEFAULT to keep the expected semantics and then
remove BLK_MQ_F_NO_SCHED as the non-disk queues never call into
elevator_init_mq or blk_register_queue which adds the sysfs attributes.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250106083531.799976-4-hch@lst.de


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 68ed4512

block/blk-mq-debugfs.c

+0 −1
Original line number Diff line number Diff line
@@ -185,7 +185,6 @@ static const char *const hctx_flag_name[] = { 
	HCTX_FLAG_NAME(STACKING),

	HCTX_FLAG_NAME(TAG_HCTX_SHARED),

	HCTX_FLAG_NAME(BLOCKING),

	HCTX_FLAG_NAME(NO_SCHED),

	HCTX_FLAG_NAME(NO_SCHED_BY_DEFAULT),

};

#undef HCTX_FLAG_NAME

block/bsg-lib.c

+1 −1
Original line number Diff line number Diff line
@@ -381,7 +381,7 @@ struct request_queue *bsg_setup_queue(struct device *dev, const char *name, 
	set->queue_depth = 128;

	set->numa_node = NUMA_NO_NODE;

	set->cmd_size = sizeof(struct bsg_job) + dd_job_size;

	set->flags = BLK_MQ_F_NO_SCHED | BLK_MQ_F_BLOCKING;

	set->flags = BLK_MQ_F_BLOCKING;

	if (blk_mq_alloc_tag_set(set))

		goto out_tag_set;

block/elevator.c

+0 −20
Original line number Diff line number Diff line
@@ -547,14 +547,6 @@ void elv_unregister(struct elevator_type *e) 
}

EXPORT_SYMBOL_GPL(elv_unregister);



static inline bool elv_support_iosched(struct request_queue *q)

{

	if (!queue_is_mq(q) ||

	    (q->tag_set->flags & BLK_MQ_F_NO_SCHED))

		return false;

	return true;

}



/*

 * For single queue devices, default to using mq-deadline. If we have multiple

 * queues or mq-deadline is not available, default to "none".
@@ -580,9 +572,6 @@ void elevator_init_mq(struct request_queue *q) 
	struct elevator_type *e;

	int err;



	if (!elv_support_iosched(q))

		return;



	WARN_ON_ONCE(blk_queue_registered(q));



	if (unlikely(q->elevator))
@@ -714,9 +703,6 @@ void elv_iosched_load_module(struct gendisk *disk, const char *buf, 
	struct elevator_type *found;

	const char *name;



	if (!elv_support_iosched(disk->queue))

		return;



	strscpy(elevator_name, buf, sizeof(elevator_name));

	name = strstrip(elevator_name);
@@ -734,9 +720,6 @@ ssize_t elv_iosched_store(struct gendisk *disk, const char *buf, 
	char elevator_name[ELV_NAME_MAX];

	int ret;



	if (!elv_support_iosched(disk->queue))

		return count;



	strscpy(elevator_name, buf, sizeof(elevator_name));

	ret = elevator_change(disk->queue, strstrip(elevator_name));

	if (!ret)
@@ -751,9 +734,6 @@ ssize_t elv_iosched_show(struct gendisk *disk, char *name) 
	struct elevator_type *cur = NULL, *e;

	int len = 0;



	if (!elv_support_iosched(q))

		return sprintf(name, "none\n");



	if (!q->elevator) {

		len += sprintf(name+len, "[none] ");

	} else {

drivers/block/null_blk/main.c

+2 −2
Original line number Diff line number Diff line
@@ -1792,7 +1792,7 @@ static int null_init_global_tag_set(void) 
	tag_set.queue_depth = g_hw_queue_depth;

	tag_set.numa_node = g_home_node;

	if (g_no_sched)

		tag_set.flags |= BLK_MQ_F_NO_SCHED;

		tag_set.flags |= BLK_MQ_F_NO_SCHED_BY_DEFAULT;

	if (g_shared_tag_bitmap)

		tag_set.flags |= BLK_MQ_F_TAG_HCTX_SHARED;

	if (g_blocking)
@@ -1817,7 +1817,7 @@ static int null_setup_tagset(struct nullb *nullb) 
	nullb->tag_set->queue_depth = nullb->dev->hw_queue_depth;

	nullb->tag_set->numa_node = nullb->dev->home_node;

	if (nullb->dev->no_sched)

		nullb->tag_set->flags |= BLK_MQ_F_NO_SCHED;

		nullb->tag_set->flags |= BLK_MQ_F_NO_SCHED_BY_DEFAULT;

	if (nullb->dev->shared_tag_bitmap)

		nullb->tag_set->flags |= BLK_MQ_F_TAG_HCTX_SHARED;

	if (nullb->dev->blocking)

drivers/nvme/host/apple.c

+0 −1
Original line number Diff line number Diff line
@@ -1251,7 +1251,6 @@ static int apple_nvme_alloc_tagsets(struct apple_nvme *anv) 
	anv->admin_tagset.timeout = NVME_ADMIN_TIMEOUT;

	anv->admin_tagset.numa_node = NUMA_NO_NODE;

	anv->admin_tagset.cmd_size = sizeof(struct apple_nvme_iod);

	anv->admin_tagset.flags = BLK_MQ_F_NO_SCHED;

	anv->admin_tagset.driver_data = &anv->adminq;



	ret = blk_mq_alloc_tag_set(&anv->admin_tagset);