/* SPDX-License-Identifier: GPL-2.0-only */#ifndef __NET_SCHED_PIE_H#define __NET_SCHED_PIE_H #include <linux/ktime.h>#include <linux/skbuff.h>#include <linux/types.h>#include <net/inet_ecn.h>#include <net/pkt_sched.h> #define MAX_PROB	(U64_MAX >> BITS_PER_BYTE)#define DTIME_INVALID	U64_MAX#define QUEUE_THRESHOLD	16384#define DQCOUNT_INVALID	-1#define PIE_SCALE	8 /** * struct pie_params - contains pie parameters * @target:		target delay in pschedtime * @tupdate:		interval at which drop probability is calculated * @limit:		total number of packets that can be in the queue * @alpha:		parameter to control drop probability * @beta:		parameter to control drop probability * @ecn:		is ECN marking of packets enabled * @bytemode:		is drop probability scaled based on pkt size * @dq_rate_estimator:	is Little's law used for qdelay calculation */struct pie_params {	psched_time_t target;	u32 tupdate;	u32 limit;	u32 alpha;	u32 beta;	u8 ecn;	u8 bytemode;	u8 dq_rate_estimator;}; /** * struct pie_vars - contains pie variables * @qdelay:		current queue delay * @qdelay_old:		queue delay in previous qdelay calculation * @burst_time:		burst time allowance * @dq_tstamp:		timestamp at which dq rate was last calculated * @prob:		drop probability * @accu_prob:		accumulated drop probability * @dq_count:		number of bytes dequeued in a measurement cycle * @avg_dq_rate:	calculated average dq rate * @backlog_old:	queue backlog during previous qdelay calculation */struct pie_vars {	psched_time_t qdelay;	psched_time_t qdelay_old;	psched_time_t burst_time;	psched_time_t dq_tstamp;	u64 prob;	u64 accu_prob;	u64 dq_count;	u32 avg_dq_rate;	u32 backlog_old;}; /** * struct pie_stats - contains pie stats * @packets_in:	total number of packets enqueued * @dropped:	packets dropped due to pie action * @overlimit:	packets dropped due to lack of space in queue * @ecn_mark:	packets marked with ECN * @maxq:	maximum queue size */struct pie_stats {	u32 packets_in;	u32 dropped;	u32 overlimit;	u32 ecn_mark;	u32 maxq;}; /** * struct pie_skb_cb - contains private skb vars * @enqueue_time:	timestamp when the packet is enqueued * @mem_usage:		size of the skb during enqueue */struct pie_skb_cb {	psched_time_t enqueue_time;	u32 mem_usage;}; static inline void pie_params_init(struct pie_params *params){	params->target = PSCHED_NS2TICKS(15 * NSEC_PER_MSEC);	/* 15 ms */	params->tupdate = usecs_to_jiffies(15 * USEC_PER_MSEC);	/* 15 ms */	params->limit = 1000;	params->alpha = 2;	params->beta = 20;	params->ecn = false;	params->bytemode = false;	params->dq_rate_estimator = false;} static inline void pie_vars_init(struct pie_vars *vars){	vars->burst_time = PSCHED_NS2TICKS(150 * NSEC_PER_MSEC); /* 150 ms */	vars->dq_tstamp = DTIME_INVALID;	vars->accu_prob = 0;	vars->dq_count = DQCOUNT_INVALID;	WRITE_ONCE(vars->avg_dq_rate, 0);} static inline struct pie_skb_cb *get_pie_cb(const struct sk_buff *skb){	qdisc_cb_private_validate(skb, sizeof(struct pie_skb_cb));	return (struct pie_skb_cb *)qdisc_skb_cb(skb)->data;} static inline psched_time_t pie_get_enqueue_time(const struct sk_buff *skb){	return get_pie_cb(skb)->enqueue_time;} static inline void pie_set_enqueue_time(struct sk_buff *skb){	get_pie_cb(skb)->enqueue_time = psched_get_time();} bool pie_drop_early(struct Qdisc *sch, struct pie_params *params,		    struct pie_vars *vars, u32 backlog, u32 packet_size); void pie_process_dequeue(struct sk_buff *skb, struct pie_params *params,			 struct pie_vars *vars, u32 backlog); void pie_calculate_probability(struct pie_params *params, struct pie_vars *vars,			       u32 backlog); #endif