From d732580b4eb31553c63744a47d590f770cafb8f0 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 5 Mar 2012 13:14:58 -0800 Subject: block: implement blk_queue_bypass_start/end() Rename and extend elv_queisce_start/end() to blk_queue_bypass_start/end() which are exported and supports nesting via @q->bypass_depth. Also add blk_queue_bypass() to test bypass state. This will be further extended and used for blkio_group management. Signed-off-by: Tejun Heo Cc: Vivek Goyal Signed-off-by: Jens Axboe --- block/elevator.c | 25 +++---------------------- 1 file changed, 3 insertions(+), 22 deletions(-) (limited to 'block/elevator.c') diff --git a/block/elevator.c b/block/elevator.c index f81c061dad15..0bdea0ed03a3 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -553,25 +553,6 @@ void elv_drain_elevator(struct request_queue *q) } } -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); - - blk_drain_queue(q, false); -} - -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) { trace_block_rq_insert(q, rq); @@ -903,7 +884,7 @@ static int elevator_switch(struct request_queue *q, struct elevator_type *new_e) * using INSERT_BACK. All requests have SOFTBARRIER set and no * merge happens either. */ - elv_quiesce_start(q); + blk_queue_bypass_start(q); /* unregister and clear all auxiliary data of the old elevator */ if (registered) @@ -933,7 +914,7 @@ static int elevator_switch(struct request_queue *q, struct elevator_type *new_e) /* done, kill the old one and finish */ elevator_exit(old); - elv_quiesce_end(q); + blk_queue_bypass_end(q); blk_add_trace_msg(q, "elv switch: %s", new_e->elevator_name); @@ -945,7 +926,7 @@ fail_init: /* switch failed, restore and re-register old elevator */ q->elevator = old; elv_register_queue(q); - elv_quiesce_end(q); + blk_queue_bypass_end(q); return err; } -- cgit