block: remove elevator_queue->ops

elevator_queue->ops points to the same ops struct ->elevator_type.ops
is pointing to.  The only effect of caching it in elevator_queue is
shorter notation - it doesn't save any indirect derefence.

Relocate elevator_type->list which used only during module init/exit
to the end of the structure, rename elevator_queue->elevator_type to
->type, and replace elevator_queue->ops with elevator_queue->type.ops.

This doesn't introduce any functional difference.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/blk.h b/block/blk.h
index 5bca266..4943770 100644 (file)
--- a/block/blk.h
+++ b/block/blk.h
@@ -94,7 +94,7 @@ static inline struct request *__elv_next_request(struct request_queue *q)
                        return NULL;
                }
                if (unlikely(blk_queue_dead(q)) ||
-                   !q->elevator->ops->elevator_dispatch_fn(q, 0))
+                   !q->elevator->type->ops.elevator_dispatch_fn(q, 0))
                        return NULL;
        }
 }
@@ -103,16 +103,16 @@ static inline void elv_activate_rq(struct request_queue *q, struct request *rq)
 {
        struct elevator_queue *e = q->elevator;
 
-       if (e->ops->elevator_activate_req_fn)
-               e->ops->elevator_activate_req_fn(q, rq);
+       if (e->type->ops.elevator_activate_req_fn)
+               e->type->ops.elevator_activate_req_fn(q, rq);
 }
 
 static inline void elv_deactivate_rq(struct request_queue *q, struct request *rq)
 {
        struct elevator_queue *e = q->elevator;
 
-       if (e->ops->elevator_deactivate_req_fn)
-               e->ops->elevator_deactivate_req_fn(q, rq);
+       if (e->type->ops.elevator_deactivate_req_fn)
+               e->type->ops.elevator_deactivate_req_fn(q, rq);
 }
 
 #ifdef CONFIG_FAIL_IO_TIMEOUT

diff --git a/block/elevator.c b/block/elevator.c
index a16c2d1..31ffe76 100644 (file)
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -61,8 +61,8 @@ static int elv_iosched_allow_merge(struct request *rq, struct bio *bio)
        struct request_queue *q = rq->q;
        struct elevator_queue *e = q->elevator;
 
-       if (e->ops->elevator_allow_merge_fn)
-               return e->ops->elevator_allow_merge_fn(q, rq, bio);
+       if (e->type->ops.elevator_allow_merge_fn)
+               return e->type->ops.elevator_allow_merge_fn(q, rq, bio);
 
        return 1;
 }
@@ -171,7 +171,7 @@ static struct elevator_type *elevator_get(const char *name)
 static int elevator_init_queue(struct request_queue *q,
                               struct elevator_queue *eq)
 {
-       eq->elevator_data = eq->ops->elevator_init_fn(q);
+       eq->elevator_data = eq->type->ops.elevator_init_fn(q);
        if (eq->elevator_data)
                return 0;
        return -ENOMEM;
@@ -203,8 +203,7 @@ static struct elevator_queue *elevator_alloc(struct request_queue *q,
        if (unlikely(!eq))
                goto err;
 
-       eq->ops = &e->ops;
-       eq->elevator_type = e;
+       eq->type = e;
        kobject_init(&eq->kobj, &elv_ktype);
        mutex_init(&eq->sysfs_lock);
 
@@ -228,7 +227,7 @@ static void elevator_release(struct kobject *kobj)
        struct elevator_queue *e;
 
        e = container_of(kobj, struct elevator_queue, kobj);
-       elevator_put(e->elevator_type);
+       elevator_put(e->type);
        kfree(e->hash);
        kfree(e);
 }
@@ -288,9 +287,8 @@ EXPORT_SYMBOL(elevator_init);
 void elevator_exit(struct elevator_queue *e)
 {
        mutex_lock(&e->sysfs_lock);
-       if (e->ops->elevator_exit_fn)
-               e->ops->elevator_exit_fn(e);
-       e->ops = NULL;
+       if (e->type->ops.elevator_exit_fn)
+               e->type->ops.elevator_exit_fn(e);
        mutex_unlock(&e->sysfs_lock);
 
        kobject_put(&e->kobj);
@@ -500,8 +498,8 @@ int elv_merge(struct request_queue *q, struct request **req, struct bio *bio)
                return ELEVATOR_BACK_MERGE;
        }
 
-       if (e->ops->elevator_merge_fn)
-               return e->ops->elevator_merge_fn(q, req, bio);
+       if (e->type->ops.elevator_merge_fn)
+               return e->type->ops.elevator_merge_fn(q, req, bio);
 
        return ELEVATOR_NO_MERGE;
 }
@@ -544,8 +542,8 @@ void elv_merged_request(struct request_queue *q, struct request *rq, int type)
 {
        struct elevator_queue *e = q->elevator;
 
-       if (e->ops->elevator_merged_fn)
-               e->ops->elevator_merged_fn(q, rq, type);
+       if (e->type->ops.elevator_merged_fn)
+               e->type->ops.elevator_merged_fn(q, rq, type);
 
        if (type == ELEVATOR_BACK_MERGE)
                elv_rqhash_reposition(q, rq);
@@ -559,8 +557,8 @@ void elv_merge_requests(struct request_queue *q, struct request *rq,
        struct elevator_queue *e = q->elevator;
        const int next_sorted = next->cmd_flags & REQ_SORTED;
 
-       if (next_sorted && e->ops->elevator_merge_req_fn)
-               e->ops->elevator_merge_req_fn(q, rq, next);
+       if (next_sorted && e->type->ops.elevator_merge_req_fn)
+               e->type->ops.elevator_merge_req_fn(q, rq, next);
 
        elv_rqhash_reposition(q, rq);
 
@@ -577,8 +575,8 @@ void elv_bio_merged(struct request_queue *q, struct request *rq,
 {
        struct elevator_queue *e = q->elevator;
 
-       if (e->ops->elevator_bio_merged_fn)
-               e->ops->elevator_bio_merged_fn(q, rq, bio);
+       if (e->type->ops.elevator_bio_merged_fn)
+               e->type->ops.elevator_bio_merged_fn(q, rq, bio);
 }
 
 void elv_requeue_request(struct request_queue *q, struct request *rq)
@@ -604,12 +602,12 @@ void elv_drain_elevator(struct request_queue *q)
 
        lockdep_assert_held(q->queue_lock);
 
-       while (q->elevator->ops->elevator_dispatch_fn(q, 1))
+       while (q->elevator->type->ops.elevator_dispatch_fn(q, 1))
                ;
        if (q->nr_sorted && printed++ < 10) {
                printk(KERN_ERR "%s: forced dispatching is broken "
                       "(nr_sorted=%u), please report this\n",
-                      q->elevator->elevator_type->elevator_name, q->nr_sorted);
+                      q->elevator->type->elevator_name, q->nr_sorted);
        }
 }
 
@@ -698,7 +696,7 @@ void __elv_add_request(struct request_queue *q, struct request *rq, int where)
                 * rq cannot be accessed after calling
                 * elevator_add_req_fn.
                 */
-               q->elevator->ops->elevator_add_req_fn(q, rq);
+               q->elevator->type->ops.elevator_add_req_fn(q, rq);
                break;
 
        case ELEVATOR_INSERT_FLUSH:
@@ -727,8 +725,8 @@ struct request *elv_latter_request(struct request_queue *q, struct request *rq)
 {
        struct elevator_queue *e = q->elevator;
 
-       if (e->ops->elevator_latter_req_fn)
-               return e->ops->elevator_latter_req_fn(q, rq);
+       if (e->type->ops.elevator_latter_req_fn)
+               return e->type->ops.elevator_latter_req_fn(q, rq);
        return NULL;
 }
 
@@ -736,8 +734,8 @@ struct request *elv_former_request(struct request_queue *q, struct request *rq)
 {
        struct elevator_queue *e = q->elevator;
 
-       if (e->ops->elevator_former_req_fn)
-               return e->ops->elevator_former_req_fn(q, rq);
+       if (e->type->ops.elevator_former_req_fn)
+               return e->type->ops.elevator_former_req_fn(q, rq);
        return NULL;
 }
 
@@ -745,8 +743,8 @@ int elv_set_request(struct request_queue *q, struct request *rq, gfp_t gfp_mask)
 {
        struct elevator_queue *e = q->elevator;
 
-       if (e->ops->elevator_set_req_fn)
-               return e->ops->elevator_set_req_fn(q, rq, gfp_mask);
+       if (e->type->ops.elevator_set_req_fn)
+               return e->type->ops.elevator_set_req_fn(q, rq, gfp_mask);
 
        rq->elevator_private[0] = NULL;
        return 0;
@@ -756,16 +754,16 @@ void elv_put_request(struct request_queue *q, struct request *rq)
 {
        struct elevator_queue *e = q->elevator;
 
-       if (e->ops->elevator_put_req_fn)
-               e->ops->elevator_put_req_fn(rq);
+       if (e->type->ops.elevator_put_req_fn)
+               e->type->ops.elevator_put_req_fn(rq);
 }
 
 int elv_may_queue(struct request_queue *q, int rw)
 {
        struct elevator_queue *e = q->elevator;
 
-       if (e->ops->elevator_may_queue_fn)
-               return e->ops->elevator_may_queue_fn(q, rw);
+       if (e->type->ops.elevator_may_queue_fn)
+               return e->type->ops.elevator_may_queue_fn(q, rw);
 
        return ELV_MQUEUE_MAY;
 }
@@ -800,8 +798,8 @@ void elv_completed_request(struct request_queue *q, struct request *rq)
        if (blk_account_rq(rq)) {
                q->in_flight[rq_is_sync(rq)]--;
                if ((rq->cmd_flags & REQ_SORTED) &&
-                   e->ops->elevator_completed_req_fn)
-                       e->ops->elevator_completed_req_fn(q, rq);
+                   e->type->ops.elevator_completed_req_fn)
+                       e->type->ops.elevator_completed_req_fn(q, rq);
        }
 }
 
@@ -819,7 +817,7 @@ elv_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
 
        e = container_of(kobj, struct elevator_queue, kobj);
        mutex_lock(&e->sysfs_lock);
-       error = e->ops ? entry->show(e, page) : -ENOENT;
+       error = e->type ? entry->show(e, page) : -ENOENT;
        mutex_unlock(&e->sysfs_lock);
        return error;
 }
@@ -837,7 +835,7 @@ elv_attr_store(struct kobject *kobj, struct attribute *attr,
 
        e = container_of(kobj, struct elevator_queue, kobj);
        mutex_lock(&e->sysfs_lock);
-       error = e->ops ? entry->store(e, page, length) : -ENOENT;
+       error = e->type ? entry->store(e, page, length) : -ENOENT;
        mutex_unlock(&e->sysfs_lock);
        return error;
 }
@@ -858,7 +856,7 @@ int __elv_register_queue(struct request_queue *q, struct elevator_queue *e)
 
        error = kobject_add(&e->kobj, &q->kobj, "%s", "iosched");
        if (!error) {
-               struct elv_fs_entry *attr = e->elevator_type->elevator_attrs;
+               struct elv_fs_entry *attr = e->type->elevator_attrs;
                if (attr) {
                        while (attr->attr.name) {
                                if (sysfs_create_file(&e->kobj, &attr->attr))
@@ -959,7 +957,7 @@ static int elevator_switch(struct request_queue *q, struct elevator_type *new_e)
        elevator_exit(old_elevator);
        elv_quiesce_end(q);
 
-       blk_add_trace_msg(q, "elv switch: %s", e->elevator_type->elevator_name);
+       blk_add_trace_msg(q, "elv switch: %s", e->type->elevator_name);
 
        return 0;
 
@@ -993,7 +991,7 @@ int elevator_change(struct request_queue *q, const char *name)
                return -EINVAL;
        }
 
-       if (!strcmp(elevator_name, q->elevator->elevator_type->elevator_name)) {
+       if (!strcmp(elevator_name, q->elevator->type->elevator_name)) {
                elevator_put(e);
                return 0;
        }
@@ -1028,7 +1026,7 @@ ssize_t elv_iosched_show(struct request_queue *q, char *name)
        if (!q->elevator || !blk_queue_stackable(q))
                return sprintf(name, "none\n");
 
-       elv = e->elevator_type;
+       elv = e->type;
 
        spin_lock(&elv_list_lock);
        list_for_each_entry(__e, &elv_list, list) {

diff --git a/include/linux/elevator.h b/include/linux/elevator.h
index 02604c8..04958ef 100644 (file)
--- a/include/linux/elevator.h
+++ b/include/linux/elevator.h
@@ -78,11 +78,11 @@ struct elv_fs_entry {
  */
 struct elevator_type
 {
-       struct list_head list;
        struct elevator_ops ops;
        struct elv_fs_entry *elevator_attrs;
        char elevator_name[ELV_NAME_MAX];
        struct module *elevator_owner;
+       struct list_head list;
 };
 
 /*
@@ -90,10 +90,9 @@ struct elevator_type
  */
 struct elevator_queue
 {
-       struct elevator_ops *ops;
+       struct elevator_type *type;
        void *elevator_data;
        struct kobject kobj;
-       struct elevator_type *elevator_type;
        struct mutex sysfs_lock;
        struct hlist_head *hash;
        unsigned int registered:1;