131 	struct dirty_throttle_control *gdtc;	/* only set in memcg dtc's */
168 static bool mdtc_valid(struct dirty_throttle_control *dtc)  in mdtc_valid()  argument
170 	return dtc->dom;  in mdtc_valid()
173 static struct wb_domain *dtc_dom(struct dirty_throttle_control *dtc)  in dtc_dom()  argument
175 	return dtc->dom;  in dtc_dom()
222 static bool mdtc_valid(struct dirty_throttle_control *dtc)  in mdtc_valid()  argument
227 static struct wb_domain *dtc_dom(struct dirty_throttle_control *dtc)  in dtc_dom()  argument
384  * @dtc: dirty_throttle_control of interest
386  * Calculate @dtc->thresh and ->bg_thresh considering
388  * must ensure that @dtc->avail is set before calling this function.  The
392 static void domain_dirty_limits(struct dirty_throttle_control *dtc)  in domain_dirty_limits()  argument
394 	const unsigned long available_memory = dtc->avail;  in domain_dirty_limits()
395 	struct dirty_throttle_control *gdtc = mdtc_gdtc(dtc);  in domain_dirty_limits()
405 	/* gdtc is !NULL iff @dtc is for memcg domain */  in domain_dirty_limits()
442 	dtc->thresh = thresh;  in domain_dirty_limits()
443 	dtc->bg_thresh = bg_thresh;  in domain_dirty_limits()
744  * @dtc: dirty_throttle_context of interest
763 static unsigned long __wb_calc_thresh(struct dirty_throttle_control *dtc)  in __wb_calc_thresh()  argument
765 	struct wb_domain *dom = dtc_dom(dtc);  in __wb_calc_thresh()
766 	unsigned long thresh = dtc->thresh;  in __wb_calc_thresh()
774 	fprop_fraction_percpu(&dom->completions, dtc->wb_completions,  in __wb_calc_thresh()
781 	wb_min_max_ratio(dtc->wb, &wb_min_ratio, &wb_max_ratio);  in __wb_calc_thresh()
903 static void wb_position_ratio(struct dirty_throttle_control *dtc)  in wb_position_ratio()  argument
905 	struct bdi_writeback *wb = dtc->wb;  in wb_position_ratio()
907 	unsigned long freerun = dirty_freerun_ceiling(dtc->thresh, dtc->bg_thresh);  in wb_position_ratio()
908 	unsigned long limit = hard_dirty_limit(dtc_dom(dtc), dtc->thresh);  in wb_position_ratio()
909 	unsigned long wb_thresh = dtc->wb_thresh;  in wb_position_ratio()
917 	dtc->pos_ratio = 0;  in wb_position_ratio()
919 	if (unlikely(dtc->dirty >= limit))  in wb_position_ratio()
928 	pos_ratio = pos_ratio_polynom(setpoint, dtc->dirty, limit);  in wb_position_ratio()
958 		if (dtc->wb_dirty < 8) {  in wb_position_ratio()
959 			dtc->pos_ratio = min_t(long long, pos_ratio * 2,  in wb_position_ratio()
964 		if (dtc->wb_dirty >= wb_thresh)  in wb_position_ratio()
968 						    dtc->wb_bg_thresh);  in wb_position_ratio()
973 		wb_pos_ratio = pos_ratio_polynom(wb_setpoint, dtc->wb_dirty,  in wb_position_ratio()
997 		dtc->pos_ratio = min(pos_ratio, wb_pos_ratio);  in wb_position_ratio()
1032 	if (unlikely(wb_thresh > dtc->thresh))  in wb_position_ratio()
1033 		wb_thresh = dtc->thresh;  in wb_position_ratio()
1041 	wb_thresh = max(wb_thresh, (limit - dtc->dirty) / 8);  in wb_position_ratio()
1046 	x = div_u64((u64)wb_thresh << 16, dtc->thresh | 1);  in wb_position_ratio()
1056 	span = (dtc->thresh - wb_thresh + 8 * write_bw) * (u64)x >> 16;  in wb_position_ratio()
1059 	if (dtc->wb_dirty < x_intercept - span / 4) {  in wb_position_ratio()
1060 		pos_ratio = div64_u64(pos_ratio * (x_intercept - dtc->wb_dirty),  in wb_position_ratio()
1071 	if (dtc->wb_dirty < x_intercept) {  in wb_position_ratio()
1072 		if (dtc->wb_dirty > x_intercept / 8)  in wb_position_ratio()
1074 					    dtc->wb_dirty);  in wb_position_ratio()
1079 	dtc->pos_ratio = pos_ratio;  in wb_position_ratio()
1132 static void update_dirty_limit(struct dirty_throttle_control *dtc)  in update_dirty_limit()  argument
1134 	struct wb_domain *dom = dtc_dom(dtc);  in update_dirty_limit()
1135 	unsigned long thresh = dtc->thresh;  in update_dirty_limit()
1151 	thresh = max(thresh, dtc->dirty);  in update_dirty_limit()
1161 static void domain_update_bandwidth(struct dirty_throttle_control *dtc,  in domain_update_bandwidth()  argument
1164 	struct wb_domain *dom = dtc_dom(dtc);  in domain_update_bandwidth()
1174 		update_dirty_limit(dtc);  in domain_update_bandwidth()
1186 static void wb_update_dirty_ratelimit(struct dirty_throttle_control *dtc,  in wb_update_dirty_ratelimit()  argument
1190 	struct bdi_writeback *wb = dtc->wb;  in wb_update_dirty_ratelimit()
1191 	unsigned long dirty = dtc->dirty;  in wb_update_dirty_ratelimit()
1192 	unsigned long freerun = dirty_freerun_ceiling(dtc->thresh, dtc->bg_thresh);  in wb_update_dirty_ratelimit()
1193 	unsigned long limit = hard_dirty_limit(dtc_dom(dtc), dtc->thresh);  in wb_update_dirty_ratelimit()
1214 					dtc->pos_ratio >> RATELIMIT_CALC_SHIFT;  in wb_update_dirty_ratelimit()
1303 		dirty = dtc->wb_dirty;  in wb_update_dirty_ratelimit()
1304 		if (dtc->wb_dirty < 8)  in wb_update_dirty_ratelimit()
1305 			setpoint = dtc->wb_dirty + 1;  in wb_update_dirty_ratelimit()
1307 			setpoint = (dtc->wb_thresh + dtc->wb_bg_thresh) / 2;  in wb_update_dirty_ratelimit()
1512 static inline void wb_dirty_limits(struct dirty_throttle_control *dtc)  in wb_dirty_limits()  argument
1514 	struct bdi_writeback *wb = dtc->wb;  in wb_dirty_limits()
1530 	dtc->wb_thresh = __wb_calc_thresh(dtc);  in wb_dirty_limits()
1531 	dtc->wb_bg_thresh = dtc->thresh ?  in wb_dirty_limits()
1532 		div_u64((u64)dtc->wb_thresh * dtc->bg_thresh, dtc->thresh) : 0;  in wb_dirty_limits()
1544 	if (dtc->wb_thresh < 2 * wb_stat_error()) {  in wb_dirty_limits()
1546 		dtc->wb_dirty = wb_reclaimable + wb_stat_sum(wb, WB_WRITEBACK);  in wb_dirty_limits()
1549 		dtc->wb_dirty = wb_reclaimable + wb_stat(wb, WB_WRITEBACK);  in wb_dirty_limits()
1671 		 * global dtc by default.  in balance_dirty_pages()
1710 		/* throttle according to the chosen dtc */  in balance_dirty_pages()