Commit 926f75f6 authored by Baolin Wang's avatar Baolin Wang Committed by Jens Axboe
Browse files

blk-iocost: Factor out the base vrate change into a separate function 



Factor out the base vrate change code into a separate function
to fimplify the ioc_timer_fn().

No functional change.

Signed-off-by: default avatarBaolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: default avatarTejun Heo <tj@kernel.org>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 2474787a

block/blk-iocost.c

+54 −45
Original line number Diff line number Diff line
@@ -971,6 +971,58 @@ static void ioc_refresh_vrate(struct ioc *ioc, struct ioc_now *now) 
	ioc->vtime_err = clamp(ioc->vtime_err, -vperiod, vperiod);

}



static void ioc_adjust_base_vrate(struct ioc *ioc, u32 rq_wait_pct,

				  int nr_lagging, int nr_shortages,

				  int prev_busy_level, u32 *missed_ppm)

{

	u64 vrate = ioc->vtime_base_rate;

	u64 vrate_min = ioc->vrate_min, vrate_max = ioc->vrate_max;



	if (!ioc->busy_level || (ioc->busy_level < 0 && nr_lagging)) {

		if (ioc->busy_level != prev_busy_level || nr_lagging)

			trace_iocost_ioc_vrate_adj(ioc, atomic64_read(&ioc->vtime_rate),

						   missed_ppm, rq_wait_pct,

						   nr_lagging, nr_shortages);



		return;

	}



	/* rq_wait signal is always reliable, ignore user vrate_min */

	if (rq_wait_pct > RQ_WAIT_BUSY_PCT)

		vrate_min = VRATE_MIN;



	/*

	 * If vrate is out of bounds, apply clamp gradually as the

	 * bounds can change abruptly.  Otherwise, apply busy_level

	 * based adjustment.

	 */

	if (vrate < vrate_min) {

		vrate = div64_u64(vrate * (100 + VRATE_CLAMP_ADJ_PCT), 100);

		vrate = min(vrate, vrate_min);

	} else if (vrate > vrate_max) {

		vrate = div64_u64(vrate * (100 - VRATE_CLAMP_ADJ_PCT), 100);

		vrate = max(vrate, vrate_max);

	} else {

		int idx = min_t(int, abs(ioc->busy_level),

				ARRAY_SIZE(vrate_adj_pct) - 1);

		u32 adj_pct = vrate_adj_pct[idx];



		if (ioc->busy_level > 0)

			adj_pct = 100 - adj_pct;

		else

			adj_pct = 100 + adj_pct;



		vrate = clamp(DIV64_U64_ROUND_UP(vrate * adj_pct, 100),

			      vrate_min, vrate_max);

	}



	trace_iocost_ioc_vrate_adj(ioc, vrate, missed_ppm, rq_wait_pct,

				   nr_lagging, nr_shortages);



	ioc->vtime_base_rate = vrate;

	ioc_refresh_margins(ioc);

}



/* take a snapshot of the current [v]time and vrate */

static void ioc_now(struct ioc *ioc, struct ioc_now *now)

{
@@ -2323,51 +2375,8 @@ static void ioc_timer_fn(struct timer_list *timer) 


	ioc->busy_level = clamp(ioc->busy_level, -1000, 1000);



	if (ioc->busy_level > 0 || (ioc->busy_level < 0 && !nr_lagging)) {

		u64 vrate = ioc->vtime_base_rate;

		u64 vrate_min = ioc->vrate_min, vrate_max = ioc->vrate_max;



		/* rq_wait signal is always reliable, ignore user vrate_min */

		if (rq_wait_pct > RQ_WAIT_BUSY_PCT)

			vrate_min = VRATE_MIN;



		/*

		 * If vrate is out of bounds, apply clamp gradually as the

		 * bounds can change abruptly.  Otherwise, apply busy_level

		 * based adjustment.

		 */

		if (vrate < vrate_min) {

			vrate = div64_u64(vrate * (100 + VRATE_CLAMP_ADJ_PCT),

					  100);

			vrate = min(vrate, vrate_min);

		} else if (vrate > vrate_max) {

			vrate = div64_u64(vrate * (100 - VRATE_CLAMP_ADJ_PCT),

					  100);

			vrate = max(vrate, vrate_max);

		} else {

			int idx = min_t(int, abs(ioc->busy_level),

					ARRAY_SIZE(vrate_adj_pct) - 1);

			u32 adj_pct = vrate_adj_pct[idx];



			if (ioc->busy_level > 0)

				adj_pct = 100 - adj_pct;

			else

				adj_pct = 100 + adj_pct;



			vrate = clamp(DIV64_U64_ROUND_UP(vrate * adj_pct, 100),

				      vrate_min, vrate_max);

		}



		trace_iocost_ioc_vrate_adj(ioc, vrate, missed_ppm, rq_wait_pct,

					   nr_lagging, nr_shortages);



		ioc->vtime_base_rate = vrate;

		ioc_refresh_margins(ioc);

	} else if (ioc->busy_level != prev_busy_level || nr_lagging) {

		trace_iocost_ioc_vrate_adj(ioc, atomic64_read(&ioc->vtime_rate),

					   missed_ppm, rq_wait_pct, nr_lagging,

					   nr_shortages);

	}

	ioc_adjust_base_vrate(ioc, rq_wait_pct, nr_lagging, nr_shortages,

			      prev_busy_level, missed_ppm);



	ioc_refresh_params(ioc, false);