Differential D25065 Diff 72442 sys/netinet/cc/cc_cubic.c

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sys/netinet/cc/cc_cubic.c

Show First 20 Lines • Show All 88 Lines • ▼ Show 20 Lines	struct cubic {
/* cwnd at the most recent congestion event. */		/* cwnd at the most recent congestion event. */
unsigned long max_cwnd;		unsigned long max_cwnd;
/* cwnd at the previous congestion event. */		/* cwnd at the previous congestion event. */
unsigned long prev_max_cwnd;		unsigned long prev_max_cwnd;
/* various flags */		/* various flags */
uint32_t flags;		uint32_t flags;
#define CUBICFLAG_cong_event 0x01 /* congestion expirienced */		#define CUBICFLAG_cong_event 0x01 /* congestion expirienced */
#define CUBICFLAG_in_slowstart 0x02 /* in slow start */		#define CUBICFLAG_in_slowstart 0x02 /* in slow start */
		#define CUBICFLAG_in_applimit 0x04 /* application limited */
/* Minimum observed rtt in ticks. */		/* Minimum observed rtt in ticks. */
int min_rtt_ticks;		int min_rtt_ticks;
/* Mean observed rtt between congestion epochs. */		/* Mean observed rtt between congestion epochs. */
int mean_rtt_ticks;		int mean_rtt_ticks;
/* ACKs since last congestion event. */		/* ACKs since last congestion event. */
int epoch_ack_count;		int epoch_ack_count;
/* Time of last congestion event in ticks. */		/* Time of last congestion event in ticks. */
int t_last_cong;		int t_last_cong;
▲ Show 20 Lines • Show All 44 Lines • ▼ Show 20 Lines	if (CCV(ccv, snd_cwnd) <= CCV(ccv, snd_ssthresh) \|\|
ticks - cubic_data->t_last_cong) < 0) {		ticks - cubic_data->t_last_cong) < 0) {
/*		/*
* dragging t_last_cong along		* dragging t_last_cong along
*/		*/
ticks_since_cong = INT_MAX;		ticks_since_cong = INT_MAX;
cubic_data->t_last_cong = ticks - INT_MAX;		cubic_data->t_last_cong = ticks - INT_MAX;
}		}

if (cubic_data->flags & CUBICFLAG_in_slowstart) {		if (cubic_data->flags & (CUBICFLAG_in_slowstart \|
cubic_data->flags &= ~CUBICFLAG_in_slowstart;		CUBICFLAG_in_applimit)) {
		cubic_data->flags &= ~(CUBICFLAG_in_slowstart \|
		CUBICFLAG_in_applimit);
cubic_data->t_last_cong = ticks;		cubic_data->t_last_cong = ticks;
cubic_data->K = 0;		cubic_data->K = 0;
}		}
/*		/*
* The mean RTT is used to best reflect the equations in		* The mean RTT is used to best reflect the equations in
* the I-D. Using min_rtt in the tf_cwnd calculation		* the I-D. Using min_rtt in the tf_cwnd calculation
* causes w_tf to grow much faster than it should if the		* causes w_tf to grow much faster than it should if the
* RTT is dominated by network buffering rather than		* RTT is dominated by network buffering rather than
▲ Show 20 Lines • Show All 43 Lines • ▼ Show 20 Lines	if (CCV(ccv, snd_cwnd) <= CCV(ccv, snd_ssthresh) \|\|
*/		*/
if (((cubic_data->flags & CUBICFLAG_cong_event) == 0) &&		if (((cubic_data->flags & CUBICFLAG_cong_event) == 0) &&
cubic_data->max_cwnd < CCV(ccv, snd_cwnd)) {		cubic_data->max_cwnd < CCV(ccv, snd_cwnd)) {
cubic_data->max_cwnd = CCV(ccv, snd_cwnd);		cubic_data->max_cwnd = CCV(ccv, snd_cwnd);
cubic_data->K = cubic_k(cubic_data->max_cwnd /		cubic_data->K = cubic_k(cubic_data->max_cwnd /
CCV(ccv, t_maxseg));		CCV(ccv, t_maxseg));
}		}
}		}
		} else if (type == CC_ACK && !IN_RECOVERY(CCV(ccv, t_flags)) &&
		!(ccv->flags & CCF_CWND_LIMITED)) {
		if (!(cubic_data->flags & CUBICFLAG_in_applimit))
		cubic_data->flags \|= CUBICFLAG_in_applimit;
}		}
}		}

/*		/*
* This is a Cubic specific implementation of after_idle.		* This is a Cubic specific implementation of after_idle.
* - Reset cwnd by calling New Reno implementation of after_idle.		* - Reset cwnd by calling New Reno implementation of after_idle.
* - Reset t_last_cong.		* - Reset t_last_cong.
*/		*/
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