block: move elevator queue allocation logic into blk_mq_init_sched

In preparation for allocating sched_tags before freezing the request
queue and acquiring ->elevator_lock, move the elevator queue allocation
logic from the elevator ops ->init_sched callback into blk_mq_init_sched.
As elevator_alloc is now only invoked from block layer core, we don't
need to export it, so unexport elevator_alloc function.

This refactoring provides a centralized location for elevator queue
initialization, which makes it easier to store pre-allocated sched_tags
in the struct elevator_queue during later changes.

Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Link: https://lore.kernel.org/r/20250730074614.2537382-2-nilay@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c
index f71ec0887733ca16d316763ddd92ab66b09126fc..aca9886c9ee3863810597ac8080d79da5b67d0d9 100644 (file)
--- a/block/bfq-iosched.c
+++ b/block/bfq-iosched.c
@@ -7218,22 +7218,16 @@ static void bfq_init_root_group(struct bfq_group *root_group,
        root_group->sched_data.bfq_class_idle_last_service = jiffies;
 }
 
-static int bfq_init_queue(struct request_queue *q, struct elevator_type *e)
+static int bfq_init_queue(struct request_queue *q, struct elevator_queue *eq)
 {
        struct bfq_data *bfqd;
-       struct elevator_queue *eq;
        unsigned int i;
        struct blk_independent_access_ranges *ia_ranges = q->disk->ia_ranges;
 
-       eq = elevator_alloc(q, e);
-       if (!eq)
-               return -ENOMEM;
-
        bfqd = kzalloc_node(sizeof(*bfqd), GFP_KERNEL, q->node);
-       if (!bfqd) {
-               kobject_put(&eq->kobj);
+       if (!bfqd)
                return -ENOMEM;
-       }
+
        eq->elevator_data = bfqd;
 
        spin_lock_irq(&q->queue_lock);
@@ -7391,7 +7385,6 @@ static int bfq_init_queue(struct request_queue *q, struct elevator_type *e)
 
 out_free:
        kfree(bfqd);
-       kobject_put(&eq->kobj);
        return -ENOMEM;
 }
 

diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c
index 55a0fd10514796e18d115af364e1d9aaf6de05a3..359e0704e09be5a002291dad51f459750efee3a0 100644 (file)
--- a/block/blk-mq-sched.c
+++ b/block/blk-mq-sched.c
@@ -475,10 +475,14 @@ int blk_mq_init_sched(struct request_queue *q, struct elevator_type *e)
        q->nr_requests = 2 * min_t(unsigned int, q->tag_set->queue_depth,
                                   BLKDEV_DEFAULT_RQ);
 
+       eq = elevator_alloc(q, e);
+       if (!eq)
+               return -ENOMEM;
+
        if (blk_mq_is_shared_tags(flags)) {
                ret = blk_mq_init_sched_shared_tags(q);
                if (ret)
-                       return ret;
+                       goto err_put_elevator;
        }
 
        queue_for_each_hw_ctx(q, hctx, i) {
@@ -487,7 +491,7 @@ int blk_mq_init_sched(struct request_queue *q, struct elevator_type *e)
                        goto err_free_map_and_rqs;
        }
 
-       ret = e->ops.init_sched(q, e);
+       ret = e->ops.init_sched(q, eq);
        if (ret)
                goto err_free_map_and_rqs;
 
@@ -508,7 +512,8 @@ int blk_mq_init_sched(struct request_queue *q, struct elevator_type *e)
 err_free_map_and_rqs:
        blk_mq_sched_free_rqs(q);
        blk_mq_sched_tags_teardown(q, flags);
-
+err_put_elevator:
+       kobject_put(&eq->kobj);
        q->elevator = NULL;
        return ret;
 }

diff --git a/block/elevator.c b/block/elevator.c
index 88f8f36bed98186687f906482f75b24097d460ae..939b0c590fbe954ad62230b17122e7011a19f25d 100644 (file)
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -148,7 +148,6 @@ struct elevator_queue *elevator_alloc(struct request_queue *q,
 
        return eq;
 }
-EXPORT_SYMBOL(elevator_alloc);
 
 static void elevator_release(struct kobject *kobj)
 {

diff --git a/block/elevator.h b/block/elevator.h
index a07ce773a38f799cf9c9b8e56c0599a0fa4c9cb6..a4de5f9ad7907700de4474176c20b73976f25844 100644 (file)
--- a/block/elevator.h
+++ b/block/elevator.h
@@ -24,7 +24,7 @@ struct blk_mq_alloc_data;
 struct blk_mq_hw_ctx;
 
 struct elevator_mq_ops {
-       int (*init_sched)(struct request_queue *, struct elevator_type *);
+       int (*init_sched)(struct request_queue *, struct elevator_queue *);
        void (*exit_sched)(struct elevator_queue *);
        int (*init_hctx)(struct blk_mq_hw_ctx *, unsigned int);
        void (*exit_hctx)(struct blk_mq_hw_ctx *, unsigned int);

diff --git a/block/kyber-iosched.c b/block/kyber-iosched.c
index 4dba8405bd015d18baf77ea37ef06d9a0ce9fd59..7b6832cb3a8d5e48cbd4f65d873474cd3fcd9f0d 100644 (file)
--- a/block/kyber-iosched.c
+++ b/block/kyber-iosched.c
@@ -402,20 +402,13 @@ err:
        return ERR_PTR(ret);
 }
 
-static int kyber_init_sched(struct request_queue *q, struct elevator_type *e)
+static int kyber_init_sched(struct request_queue *q, struct elevator_queue *eq)
 {
        struct kyber_queue_data *kqd;
-       struct elevator_queue *eq;
-
-       eq = elevator_alloc(q, e);
-       if (!eq)
-               return -ENOMEM;
 
        kqd = kyber_queue_data_alloc(q);
-       if (IS_ERR(kqd)) {
-               kobject_put(&eq->kobj);
+       if (IS_ERR(kqd))
                return PTR_ERR(kqd);
-       }
 
        blk_stat_enable_accounting(q);
 

diff --git a/block/mq-deadline.c b/block/mq-deadline.c
index 2edf1cac06d5b800ea543941b50c1bc617996203..7b6caf30e00aee2f87f467f7fb3c84451bf8dd11 100644 (file)
--- a/block/mq-deadline.c
+++ b/block/mq-deadline.c
@@ -568,20 +568,14 @@ static void dd_exit_sched(struct elevator_queue *e)
 /*
  * initialize elevator private data (deadline_data).
  */
-static int dd_init_sched(struct request_queue *q, struct elevator_type *e)
+static int dd_init_sched(struct request_queue *q, struct elevator_queue *eq)
 {
        struct deadline_data *dd;
-       struct elevator_queue *eq;
        enum dd_prio prio;
-       int ret = -ENOMEM;
-
-       eq = elevator_alloc(q, e);
-       if (!eq)
-               return ret;
 
        dd = kzalloc_node(sizeof(*dd), GFP_KERNEL, q->node);
        if (!dd)
-               goto put_eq;
+               return -ENOMEM;
 
        eq->elevator_data = dd;
 
@@ -608,10 +602,6 @@ static int dd_init_sched(struct request_queue *q, struct elevator_type *e)
 
        q->elevator = eq;
        return 0;
-
-put_eq:
-       kobject_put(&eq->kobj);
-       return ret;
 }
 
 /*