Make sure we have helpers for all relevant module refcount operations on
the elevator_type in elevator.h, and use them. Move the call to the get
helper in blk_mq_elv_switch_none a bit so that it is obvious with a less
verbose comment.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
block/blk-mq.c | 11 ++---------
block/elevator.c | 9 ++-------
block/elevator.h | 15 +++++++++++++++
3 files changed, 19 insertions(+), 16 deletions(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 33292c01875d5..9db8814cdd02b 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -4554,17 +4554,10 @@ static bool blk_mq_elv_switch_none(struct list_head *head,
INIT_LIST_HEAD(&qe->node);
qe->q = q;
+ /* keep a reference to the elevator module as we'll switch back */
+ __elevator_get(qe->type);
qe->type = q->elevator->type;
list_add(&qe->node, head);
-
- /*
- * After elevator_switch, the previous elevator_queue will be
- * released by elevator_release. The reference of the io scheduler
- * module get by elevator_get will also be put. So we need to get
- * a reference of the io scheduler module here to prevent it to be
- * removed.
- */
- __module_get(qe->type->elevator_owner);
elevator_switch(q, NULL);
mutex_unlock(&q->sysfs_lock);
diff --git a/block/elevator.c b/block/elevator.c
index bd71f0fc4e4b6..40ba43aa9ece0 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -132,11 +132,6 @@ static struct elevator_type *elevator_find(const char *name,
return NULL;
}
-static void elevator_put(struct elevator_type *e)
-{
- module_put(e->elevator_owner);
-}
-
static struct elevator_type *elevator_get(struct request_queue *q,
const char *name, bool try_loading)
{
@@ -152,7 +147,7 @@ static struct elevator_type *elevator_get(struct request_queue *q,
e = elevator_find(name, q->required_elevator_features);
}
- if (e && !try_module_get(e->elevator_owner))
+ if (e && !elevator_tryget(e))
e = NULL;
spin_unlock(&elv_list_lock);
@@ -663,7 +658,7 @@ static struct elevator_type *elevator_get_by_features(struct request_queue *q)
}
}
- if (found && !try_module_get(found->elevator_owner))
+ if (found && !elevator_tryget(found))
found = NULL;
spin_unlock(&elv_list_lock);
diff --git a/block/elevator.h b/block/elevator.h
index 3f0593b3bf9d3..44e5f35fa740d 100644
--- a/block/elevator.h
+++ b/block/elevator.h
@@ -84,6 +84,21 @@ struct elevator_type
struct list_head list;
};
+static inline bool elevator_tryget(struct elevator_type *e)
+{
+ return try_module_get(e->elevator_owner);
+}
+
+static inline void __elevator_get(struct elevator_type *e)
+{
+ __module_get(e->elevator_owner);
+}
+
+static inline void elevator_put(struct elevator_type *e)
+{
+ module_put(e->elevator_owner);
+}
+
#define ELV_HASH_BITS 6
void elv_rqhash_del(struct request_queue *q, struct request *rq);
--
2.30.2
