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Diffstat (limited to 'block/elevator.c')
-rw-r--r--block/elevator.c37
1 files changed, 11 insertions, 26 deletions
diff --git a/block/elevator.c b/block/elevator.c
index cb332cb7ac6b..74a277ffed39 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -31,7 +31,6 @@
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/compiler.h>
-#include <linux/delay.h>
#include <linux/blktrace_api.h>
#include <linux/hash.h>
#include <linux/uaccess.h>
@@ -606,43 +605,35 @@ void elv_requeue_request(struct request_queue *q, struct request *rq)
void elv_drain_elevator(struct request_queue *q)
{
static int printed;
+
+ lockdep_assert_held(q->queue_lock);
+
while (q->elevator->ops->elevator_dispatch_fn(q, 1))
;
- if (q->nr_sorted == 0)
- return;
- if (printed++ < 10) {
+ 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);
}
}
-/*
- * Call with queue lock held, interrupts disabled
- */
void elv_quiesce_start(struct request_queue *q)
{
if (!q->elevator)
return;
+ spin_lock_irq(q->queue_lock);
queue_flag_set(QUEUE_FLAG_ELVSWITCH, q);
+ spin_unlock_irq(q->queue_lock);
- /*
- * make sure we don't have any requests in flight
- */
- elv_drain_elevator(q);
- while (q->rq.elvpriv) {
- __blk_run_queue(q);
- spin_unlock_irq(q->queue_lock);
- msleep(10);
- spin_lock_irq(q->queue_lock);
- elv_drain_elevator(q);
- }
+ blk_drain_queue(q);
}
void elv_quiesce_end(struct request_queue *q)
{
+ spin_lock_irq(q->queue_lock);
queue_flag_clear(QUEUE_FLAG_ELVSWITCH, q);
+ spin_unlock_irq(q->queue_lock);
}
void __elv_add_request(struct request_queue *q, struct request *rq, int where)
@@ -972,7 +963,6 @@ static int elevator_switch(struct request_queue *q, struct elevator_type *new_e)
/*
* Turn on BYPASS and drain all requests w/ elevator private data
*/
- spin_lock_irq(q->queue_lock);
elv_quiesce_start(q);
/*
@@ -983,8 +973,8 @@ static int elevator_switch(struct request_queue *q, struct elevator_type *new_e)
/*
* attach and start new elevator
*/
+ spin_lock_irq(q->queue_lock);
elevator_attach(q, e, data);
-
spin_unlock_irq(q->queue_lock);
if (old_elevator->registered) {
@@ -999,9 +989,7 @@ static int elevator_switch(struct request_queue *q, struct elevator_type *new_e)
* finally exit old elevator and turn off BYPASS.
*/
elevator_exit(old_elevator);
- spin_lock_irq(q->queue_lock);
elv_quiesce_end(q);
- spin_unlock_irq(q->queue_lock);
blk_add_trace_msg(q, "elv switch: %s", e->elevator_type->elevator_name);
@@ -1015,10 +1003,7 @@ fail_register:
elevator_exit(e);
q->elevator = old_elevator;
elv_register_queue(q);
-
- spin_lock_irq(q->queue_lock);
- queue_flag_clear(QUEUE_FLAG_ELVSWITCH, q);
- spin_unlock_irq(q->queue_lock);
+ elv_quiesce_end(q);
return err;
}