Commit 4cff729f authored by Shaohua Li's avatar Shaohua Li Committed by Jens Axboe
Browse files

blk-throttle: output some debug info in trace 



These info are important to understand what's happening and help debug.

Signed-off-by: default avatarShaohua Li <shli@fb.com>
Acked-by: default avatarTejun Heo <tj@kernel.org>
Signed-off-by: default avatarJens Axboe <axboe@fb.com>
parent 5b81fc3c

block/blk-throttle.c

+14 −1
Original line number Diff line number Diff line
@@ -1748,12 +1748,18 @@ static bool throtl_tg_is_idle(struct throtl_grp *tg) 
	 * - IO latency is largely below threshold

	 */

	unsigned long time = jiffies_to_usecs(4 * tg->td->throtl_slice);

	bool ret;



	time = min_t(unsigned long, MAX_IDLE_TIME, time);

	return (ktime_get_ns() >> 10) - tg->last_finish_time > time ||

	ret = (ktime_get_ns() >> 10) - tg->last_finish_time > time ||

	       tg->avg_idletime > tg->idletime_threshold ||

	       (tg->latency_target && tg->bio_cnt &&

		tg->bad_bio_cnt * 5 < tg->bio_cnt);

	throtl_log(&tg->service_queue,

		"avg_idle=%ld, idle_threshold=%ld, bad_bio=%d, total_bio=%d, is_idle=%d, scale=%d",

		tg->avg_idletime, tg->idletime_threshold, tg->bad_bio_cnt,

		tg->bio_cnt, ret, tg->td->scale);

	return ret;

}



static bool throtl_tg_can_upgrade(struct throtl_grp *tg)
@@ -1849,6 +1855,7 @@ static void throtl_upgrade_state(struct throtl_data *td) 
	struct cgroup_subsys_state *pos_css;

	struct blkcg_gq *blkg;



	throtl_log(&td->service_queue, "upgrade to max");

	td->limit_index = LIMIT_MAX;

	td->low_upgrade_time = jiffies;

	td->scale = 0;
@@ -1871,6 +1878,7 @@ static void throtl_downgrade_state(struct throtl_data *td, int new) 
{

	td->scale /= 2;



	throtl_log(&td->service_queue, "downgrade, scale %d", td->scale);

	if (td->scale) {

		td->low_upgrade_time = jiffies - td->scale * td->throtl_slice;

		return;
@@ -2044,6 +2052,11 @@ static void throtl_update_latency_buckets(struct throtl_data *td) 
		td->avg_buckets[i].valid = true;

		last_latency = td->avg_buckets[i].latency;

	}



	for (i = 0; i < LATENCY_BUCKET_SIZE; i++)

		throtl_log(&td->service_queue,

			"Latency bucket %d: latency=%ld, valid=%d", i,

			td->avg_buckets[i].latency, td->avg_buckets[i].valid);

}

#else

static inline void throtl_update_latency_buckets(struct throtl_data *td)