Commit b6c7b58f authored by Josef Bacik's avatar Josef Bacik Committed by Jens Axboe
Browse files

block: convert wbt_wait() to use rq_qos_wait() 



Now that we have rq_qos_wait() in place, convert wbt_wait() over to
using it with it's specific callbacks.

Signed-off-by: default avatarJosef Bacik <josef@toxicpanda.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 84f60324

block/blk-wbt.c

+11 −54
Original line number Diff line number Diff line
@@ -489,31 +489,21 @@ static inline unsigned int get_limit(struct rq_wb *rwb, unsigned long rw) 
}



struct wbt_wait_data {

	struct wait_queue_entry wq;

	struct task_struct *task;

	struct rq_wb *rwb;

	struct rq_wait *rqw;

	enum wbt_flags wb_acct;

	unsigned long rw;

	bool got_token;

};



static int wbt_wake_function(struct wait_queue_entry *curr, unsigned int mode,

			     int wake_flags, void *key)

static bool wbt_inflight_cb(struct rq_wait *rqw, void *private_data)

{

	struct wbt_wait_data *data = container_of(curr, struct wbt_wait_data,

							wq);



	/*

	 * If we fail to get a budget, return -1 to interrupt the wake up

	 * loop in __wake_up_common.

	 */

	if (!rq_wait_inc_below(data->rqw, get_limit(data->rwb, data->rw)))

		return -1;

	struct wbt_wait_data *data = private_data;

	return rq_wait_inc_below(rqw, get_limit(data->rwb, data->rw));

}



	data->got_token = true;

	list_del_init(&curr->entry);

	wake_up_process(data->task);

	return 1;

static void wbt_cleanup_cb(struct rq_wait *rqw, void *private_data)

{

	struct wbt_wait_data *data = private_data;

	wbt_rqw_done(data->rwb, rqw, data->wb_acct);

}



/*
@@ -525,45 +515,12 @@ static void __wbt_wait(struct rq_wb *rwb, enum wbt_flags wb_acct, 
{

	struct rq_wait *rqw = get_rq_wait(rwb, wb_acct);

	struct wbt_wait_data data = {

		.wq = {

			.func	= wbt_wake_function,

			.entry	= LIST_HEAD_INIT(data.wq.entry),

		},

		.task = current,

		.rwb = rwb,

		.rqw = rqw,

		.wb_acct = wb_acct,

		.rw = rw,

	};

	bool has_sleeper;



	has_sleeper = wq_has_sleeper(&rqw->wait);

	if (!has_sleeper && rq_wait_inc_below(rqw, get_limit(rwb, rw)))

		return;



	prepare_to_wait_exclusive(&rqw->wait, &data.wq, TASK_UNINTERRUPTIBLE);

	do {

		if (data.got_token)

			break;



		if (!has_sleeper &&

		    rq_wait_inc_below(rqw, get_limit(rwb, rw))) {

			finish_wait(&rqw->wait, &data.wq);



			/*

			 * We raced with wbt_wake_function() getting a token,

			 * which means we now have two. Put our local token

			 * and wake anyone else potentially waiting for one.

			 */

			if (data.got_token)

				wbt_rqw_done(rwb, rqw, wb_acct);

			break;

		}



		io_schedule();

		has_sleeper = false;

	} while (1);



	finish_wait(&rqw->wait, &data.wq);

	rq_qos_wait(rqw, &data, wbt_inflight_cb, wbt_cleanup_cb);

}



static inline bool wbt_should_throttle(struct rq_wb *rwb, struct bio *bio)