389 static void cobalt_newton_step(struct cobalt_vars *vars)  in cobalt_newton_step()  argument
394 	invsqrt = vars->rec_inv_sqrt;  in cobalt_newton_step()
396 	val = (3LL << 32) - ((u64)vars->count * invsqrt2);  in cobalt_newton_step()
401 	vars->rec_inv_sqrt = val;  in cobalt_newton_step()
404 static void cobalt_invsqrt(struct cobalt_vars *vars)  in cobalt_invsqrt()  argument
406 	if (vars->count < REC_INV_SQRT_CACHE)  in cobalt_invsqrt()
407 		vars->rec_inv_sqrt = inv_sqrt_cache[vars->count];  in cobalt_invsqrt()
409 		cobalt_newton_step(vars);  in cobalt_invsqrt()
412 static void cobalt_vars_init(struct cobalt_vars *vars)  in cobalt_vars_init()  argument
414 	memset(vars, 0, sizeof(*vars));  in cobalt_vars_init()
432 static bool cobalt_queue_full(struct cobalt_vars *vars,  in cobalt_queue_full()  argument
438 	if (ktime_to_ns(ktime_sub(now, vars->blue_timer)) > p->target) {  in cobalt_queue_full()
439 		up = !vars->p_drop;  in cobalt_queue_full()
440 		vars->p_drop += p->p_inc;  in cobalt_queue_full()
441 		if (vars->p_drop < p->p_inc)  in cobalt_queue_full()
442 			vars->p_drop = ~0;  in cobalt_queue_full()
443 		vars->blue_timer = now;  in cobalt_queue_full()
445 	vars->dropping = true;  in cobalt_queue_full()
446 	vars->drop_next = now;  in cobalt_queue_full()
447 	if (!vars->count)  in cobalt_queue_full()
448 		vars->count = 1;  in cobalt_queue_full()
456 static bool cobalt_queue_empty(struct cobalt_vars *vars,  in cobalt_queue_empty()  argument
462 	if (vars->p_drop &&  in cobalt_queue_empty()
463 	    ktime_to_ns(ktime_sub(now, vars->blue_timer)) > p->target) {  in cobalt_queue_empty()
464 		if (vars->p_drop < p->p_dec)  in cobalt_queue_empty()
465 			vars->p_drop = 0;  in cobalt_queue_empty()
467 			vars->p_drop -= p->p_dec;  in cobalt_queue_empty()
468 		vars->blue_timer = now;  in cobalt_queue_empty()
469 		down = !vars->p_drop;  in cobalt_queue_empty()
471 	vars->dropping = false;  in cobalt_queue_empty()
473 	if (vars->count && ktime_to_ns(ktime_sub(now, vars->drop_next)) >= 0) {  in cobalt_queue_empty()
474 		vars->count--;  in cobalt_queue_empty()
475 		cobalt_invsqrt(vars);  in cobalt_queue_empty()
476 		vars->drop_next = cobalt_control(vars->drop_next,  in cobalt_queue_empty()
478 						 vars->rec_inv_sqrt);  in cobalt_queue_empty()
487 static enum skb_drop_reason cobalt_should_drop(struct cobalt_vars *vars,  in cobalt_should_drop()  argument
514 	schedule = ktime_sub(now, vars->drop_next);  in cobalt_should_drop()
518 	next_due = vars->count && ktime_to_ns(schedule) >= 0;  in cobalt_should_drop()
520 	vars->ecn_marked = false;  in cobalt_should_drop()
523 		if (!vars->dropping) {  in cobalt_should_drop()
524 			vars->dropping = true;  in cobalt_should_drop()
525 			vars->drop_next = cobalt_control(now,  in cobalt_should_drop()
527 							 vars->rec_inv_sqrt);  in cobalt_should_drop()
529 		if (!vars->count)  in cobalt_should_drop()
530 			vars->count = 1;  in cobalt_should_drop()
531 	} else if (vars->dropping) {  in cobalt_should_drop()
532 		vars->dropping = false;  in cobalt_should_drop()
535 	if (next_due && vars->dropping) {  in cobalt_should_drop()
537 		if (!(vars->ecn_marked = INET_ECN_set_ce(skb)))  in cobalt_should_drop()
540 		vars->count++;  in cobalt_should_drop()
541 		if (!vars->count)  in cobalt_should_drop()
542 			vars->count--;  in cobalt_should_drop()
543 		cobalt_invsqrt(vars);  in cobalt_should_drop()
544 		vars->drop_next = cobalt_control(vars->drop_next,  in cobalt_should_drop()
546 						 vars->rec_inv_sqrt);  in cobalt_should_drop()
547 		schedule = ktime_sub(now, vars->drop_next);  in cobalt_should_drop()
550 			vars->count--;  in cobalt_should_drop()
551 			cobalt_invsqrt(vars);  in cobalt_should_drop()
552 			vars->drop_next = cobalt_control(vars->drop_next,  in cobalt_should_drop()
554 							 vars->rec_inv_sqrt);  in cobalt_should_drop()
555 			schedule = ktime_sub(now, vars->drop_next);  in cobalt_should_drop()
556 			next_due = vars->count && ktime_to_ns(schedule) >= 0;  in cobalt_should_drop()
561 	if (vars->p_drop && reason == SKB_NOT_DROPPED_YET &&  in cobalt_should_drop()
562 	    get_random_u32() < vars->p_drop)  in cobalt_should_drop()
566 	if (!vars->count)  in cobalt_should_drop()
567 		vars->drop_next = ktime_add_ns(now, p->interval);  in cobalt_should_drop()
569 		vars->drop_next = now;  in cobalt_should_drop()