[linux.git] / include / linux / net_dim.h

/*
 * Copyright (c) 2016, Mellanox Technologies. All rights reserved.
 * Copyright (c) 2017-2018, Broadcom Limited. All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#ifndef NET_DIM_H
#define NET_DIM_H

#include <linux/module.h>

struct net_dim_cq_moder {
	u16 usec;
	u16 pkts;
	u8 cq_period_mode;
};

struct net_dim_sample {
	ktime_t time;
	u32     pkt_ctr;
	u32     byte_ctr;
	u16     event_ctr;
};

struct net_dim_stats {
	int ppms; /* packets per msec */
	int bpms; /* bytes per msec */
	int epms; /* events per msec */
};

struct net_dim { /* Adaptive Moderation */
	u8                                      state;
	struct net_dim_stats                    prev_stats;
	struct net_dim_sample                   start_sample;
	struct work_struct                      work;
	u8                                      profile_ix;
	u8                                      mode;
	u8                                      tune_state;
	u8                                      steps_right;
	u8                                      steps_left;
	u8                                      tired;
};

enum {
	NET_DIM_CQ_PERIOD_MODE_START_FROM_EQE = 0x0,
	NET_DIM_CQ_PERIOD_MODE_START_FROM_CQE = 0x1,
	NET_DIM_CQ_PERIOD_NUM_MODES
};

/* Adaptive moderation logic */
enum {
	NET_DIM_START_MEASURE,
	NET_DIM_MEASURE_IN_PROGRESS,
	NET_DIM_APPLY_NEW_PROFILE,
};

enum {
	NET_DIM_PARKING_ON_TOP,
	NET_DIM_PARKING_TIRED,
	NET_DIM_GOING_RIGHT,
	NET_DIM_GOING_LEFT,
};

enum {
	NET_DIM_STATS_WORSE,
	NET_DIM_STATS_SAME,
	NET_DIM_STATS_BETTER,
};

enum {
	NET_DIM_STEPPED,
	NET_DIM_TOO_TIRED,
	NET_DIM_ON_EDGE,
};

#define NET_DIM_PARAMS_NUM_PROFILES 5
/* Adaptive moderation profiles */
#define NET_DIM_DEFAULT_RX_CQ_MODERATION_PKTS_FROM_EQE 256
#define NET_DIM_DEFAULT_TX_CQ_MODERATION_PKTS_FROM_EQE 128
#define NET_DIM_DEF_PROFILE_CQE 1
#define NET_DIM_DEF_PROFILE_EQE 1

/* All profiles sizes must be NET_PARAMS_DIM_NUM_PROFILES */
#define NET_DIM_RX_EQE_PROFILES { \
	{1,   NET_DIM_DEFAULT_RX_CQ_MODERATION_PKTS_FROM_EQE}, \
	{8,   NET_DIM_DEFAULT_RX_CQ_MODERATION_PKTS_FROM_EQE}, \
	{64,  NET_DIM_DEFAULT_RX_CQ_MODERATION_PKTS_FROM_EQE}, \
	{128, NET_DIM_DEFAULT_RX_CQ_MODERATION_PKTS_FROM_EQE}, \
	{256, NET_DIM_DEFAULT_RX_CQ_MODERATION_PKTS_FROM_EQE}, \
}

#define NET_DIM_RX_CQE_PROFILES { \
	{2,  256},             \
	{8,  128},             \
	{16, 64},              \
	{32, 64},              \
	{64, 64}               \
}

#define NET_DIM_TX_EQE_PROFILES { \
	{1,   NET_DIM_DEFAULT_TX_CQ_MODERATION_PKTS_FROM_EQE},  \
	{8,   NET_DIM_DEFAULT_TX_CQ_MODERATION_PKTS_FROM_EQE},  \
	{32,  NET_DIM_DEFAULT_TX_CQ_MODERATION_PKTS_FROM_EQE},  \
	{64,  NET_DIM_DEFAULT_TX_CQ_MODERATION_PKTS_FROM_EQE},  \
	{128, NET_DIM_DEFAULT_TX_CQ_MODERATION_PKTS_FROM_EQE}   \
}

#define NET_DIM_TX_CQE_PROFILES { \
	{5,  128},  \
	{8,  64},  \
	{16, 32},  \
	{32, 32},  \
	{64, 32}   \
}

static const struct net_dim_cq_moder
rx_profile[NET_DIM_CQ_PERIOD_NUM_MODES][NET_DIM_PARAMS_NUM_PROFILES] = {
	NET_DIM_RX_EQE_PROFILES,
	NET_DIM_RX_CQE_PROFILES,
};

static const struct net_dim_cq_moder
tx_profile[NET_DIM_CQ_PERIOD_NUM_MODES][NET_DIM_PARAMS_NUM_PROFILES] = {
	NET_DIM_TX_EQE_PROFILES,
	NET_DIM_TX_CQE_PROFILES,
};

static inline struct net_dim_cq_moder
net_dim_get_rx_moderation(u8 cq_period_mode, int ix)
{
	struct net_dim_cq_moder cq_moder = rx_profile[cq_period_mode][ix];

	cq_moder.cq_period_mode = cq_period_mode;
	return cq_moder;
}

static inline struct net_dim_cq_moder
net_dim_get_def_rx_moderation(u8 cq_period_mode)
{
	u8 profile_ix = cq_period_mode == NET_DIM_CQ_PERIOD_MODE_START_FROM_CQE ?
			NET_DIM_DEF_PROFILE_CQE : NET_DIM_DEF_PROFILE_EQE;

	return net_dim_get_rx_moderation(cq_period_mode, profile_ix);
}

static inline struct net_dim_cq_moder
net_dim_get_tx_moderation(u8 cq_period_mode, int ix)
{
	struct net_dim_cq_moder cq_moder = tx_profile[cq_period_mode][ix];

	cq_moder.cq_period_mode = cq_period_mode;
	return cq_moder;
}

static inline struct net_dim_cq_moder
net_dim_get_def_tx_moderation(u8 cq_period_mode)
{
	u8 profile_ix = cq_period_mode == NET_DIM_CQ_PERIOD_MODE_START_FROM_CQE ?
			NET_DIM_DEF_PROFILE_CQE : NET_DIM_DEF_PROFILE_EQE;

	return net_dim_get_tx_moderation(cq_period_mode, profile_ix);
}

static inline bool net_dim_on_top(struct net_dim *dim)
{
	switch (dim->tune_state) {
	case NET_DIM_PARKING_ON_TOP:
	case NET_DIM_PARKING_TIRED:
		return true;
	case NET_DIM_GOING_RIGHT:
		return (dim->steps_left > 1) && (dim->steps_right == 1);
	default: /* NET_DIM_GOING_LEFT */
		return (dim->steps_right > 1) && (dim->steps_left == 1);
	}
}

static inline void net_dim_turn(struct net_dim *dim)
{
	switch (dim->tune_state) {
	case NET_DIM_PARKING_ON_TOP:
	case NET_DIM_PARKING_TIRED:
		break;
	case NET_DIM_GOING_RIGHT:
		dim->tune_state = NET_DIM_GOING_LEFT;
		dim->steps_left = 0;
		break;
	case NET_DIM_GOING_LEFT:
		dim->tune_state = NET_DIM_GOING_RIGHT;
		dim->steps_right = 0;
		break;
	}
}

static inline int net_dim_step(struct net_dim *dim)
{
	if (dim->tired == (NET_DIM_PARAMS_NUM_PROFILES * 2))
		return NET_DIM_TOO_TIRED;

	switch (dim->tune_state) {
	case NET_DIM_PARKING_ON_TOP:
	case NET_DIM_PARKING_TIRED:
		break;
	case NET_DIM_GOING_RIGHT:
		if (dim->profile_ix == (NET_DIM_PARAMS_NUM_PROFILES - 1))
			return NET_DIM_ON_EDGE;
		dim->profile_ix++;
		dim->steps_right++;
		break;
	case NET_DIM_GOING_LEFT:
		if (dim->profile_ix == 0)
			return NET_DIM_ON_EDGE;
		dim->profile_ix--;
		dim->steps_left++;
		break;
	}

	dim->tired++;
	return NET_DIM_STEPPED;
}

static inline void net_dim_park_on_top(struct net_dim *dim)
{
	dim->steps_right  = 0;
	dim->steps_left   = 0;
	dim->tired        = 0;
	dim->tune_state   = NET_DIM_PARKING_ON_TOP;
}

static inline void net_dim_park_tired(struct net_dim *dim)
{
	dim->steps_right  = 0;
	dim->steps_left   = 0;
	dim->tune_state   = NET_DIM_PARKING_TIRED;
}

static inline void net_dim_exit_parking(struct net_dim *dim)
{
	dim->tune_state = dim->profile_ix ? NET_DIM_GOING_LEFT :
					  NET_DIM_GOING_RIGHT;
	net_dim_step(dim);
}

#define IS_SIGNIFICANT_DIFF(val, ref) \
	(((100UL * abs((val) - (ref))) / (ref)) > 10) /* more than 10% difference */

static inline int net_dim_stats_compare(struct net_dim_stats *curr,
					struct net_dim_stats *prev)
{
	if (!prev->bpms)
		return curr->bpms ? NET_DIM_STATS_BETTER :
				    NET_DIM_STATS_SAME;

	if (IS_SIGNIFICANT_DIFF(curr->bpms, prev->bpms))
		return (curr->bpms > prev->bpms) ? NET_DIM_STATS_BETTER :
						   NET_DIM_STATS_WORSE;

	if (!prev->ppms)
		return curr->ppms ? NET_DIM_STATS_BETTER :
				    NET_DIM_STATS_SAME;

	if (IS_SIGNIFICANT_DIFF(curr->ppms, prev->ppms))
		return (curr->ppms > prev->ppms) ? NET_DIM_STATS_BETTER :
						   NET_DIM_STATS_WORSE;

	if (!prev->epms)
		return NET_DIM_STATS_SAME;

	if (IS_SIGNIFICANT_DIFF(curr->epms, prev->epms))
		return (curr->epms < prev->epms) ? NET_DIM_STATS_BETTER :
						   NET_DIM_STATS_WORSE;

	return NET_DIM_STATS_SAME;
}

static inline bool net_dim_decision(struct net_dim_stats *curr_stats,
				    struct net_dim *dim)
{
	int prev_state = dim->tune_state;
	int prev_ix = dim->profile_ix;
	int stats_res;
	int step_res;

	switch (dim->tune_state) {
	case NET_DIM_PARKING_ON_TOP:
		stats_res = net_dim_stats_compare(curr_stats, &dim->prev_stats);
		if (stats_res != NET_DIM_STATS_SAME)
			net_dim_exit_parking(dim);
		break;

	case NET_DIM_PARKING_TIRED:
		dim->tired--;
		if (!dim->tired)
			net_dim_exit_parking(dim);
		break;

	case NET_DIM_GOING_RIGHT:
	case NET_DIM_GOING_LEFT:
		stats_res = net_dim_stats_compare(curr_stats, &dim->prev_stats);
		if (stats_res != NET_DIM_STATS_BETTER)
			net_dim_turn(dim);

		if (net_dim_on_top(dim)) {
			net_dim_park_on_top(dim);
			break;
		}

		step_res = net_dim_step(dim);
		switch (step_res) {
		case NET_DIM_ON_EDGE:
			net_dim_park_on_top(dim);
			break;
		case NET_DIM_TOO_TIRED:
			net_dim_park_tired(dim);
			break;
		}

		break;
	}

	if ((prev_state      != NET_DIM_PARKING_ON_TOP) ||
	    (dim->tune_state != NET_DIM_PARKING_ON_TOP))
		dim->prev_stats = *curr_stats;

	return dim->profile_ix != prev_ix;
}

static inline void net_dim_sample(u16 event_ctr,
				  u64 packets,
				  u64 bytes,
				  struct net_dim_sample *s)
{
	s->time	     = ktime_get();
	s->pkt_ctr   = packets;
	s->byte_ctr  = bytes;
	s->event_ctr = event_ctr;
}

#define NET_DIM_NEVENTS 64
#define BIT_GAP(bits, end, start) ((((end) - (start)) + BIT_ULL(bits)) & (BIT_ULL(bits) - 1))

static inline void net_dim_calc_stats(struct net_dim_sample *start,
				      struct net_dim_sample *end,
				      struct net_dim_stats *curr_stats)
{
	/* u32 holds up to 71 minutes, should be enough */
	u32 delta_us = ktime_us_delta(end->time, start->time);
	u32 npkts = BIT_GAP(BITS_PER_TYPE(u32), end->pkt_ctr, start->pkt_ctr);
	u32 nbytes = BIT_GAP(BITS_PER_TYPE(u32), end->byte_ctr,
			     start->byte_ctr);

	if (!delta_us)
		return;

	curr_stats->ppms = DIV_ROUND_UP(npkts * USEC_PER_MSEC, delta_us);
	curr_stats->bpms = DIV_ROUND_UP(nbytes * USEC_PER_MSEC, delta_us);
	curr_stats->epms = DIV_ROUND_UP(NET_DIM_NEVENTS * USEC_PER_MSEC,
					delta_us);
}

static inline void net_dim(struct net_dim *dim,
			   struct net_dim_sample end_sample)
{
	struct net_dim_stats curr_stats;
	u16 nevents;

	switch (dim->state) {
	case NET_DIM_MEASURE_IN_PROGRESS:
		nevents = BIT_GAP(BITS_PER_TYPE(u16),
				  end_sample.event_ctr,
				  dim->start_sample.event_ctr);
		if (nevents < NET_DIM_NEVENTS)
			break;
		net_dim_calc_stats(&dim->start_sample, &end_sample,
				   &curr_stats);
		if (net_dim_decision(&curr_stats, dim)) {
			dim->state = NET_DIM_APPLY_NEW_PROFILE;
			schedule_work(&dim->work);
			break;
		}
		/* fall through */
	case NET_DIM_START_MEASURE:
		net_dim_sample(end_sample.event_ctr, end_sample.pkt_ctr, end_sample.byte_ctr,
			       &dim->start_sample);
		dim->state = NET_DIM_MEASURE_IN_PROGRESS;
		break;
	case NET_DIM_APPLY_NEW_PROFILE:
		break;
	}
}

#endif /* NET_DIM_H */
Commit	Line	Data
cb3c7fd4 GR	1	/*
cb3c7fd4 GR	2	* Copyright (c) 2016, Mellanox Technologies. All rights reserved.
b9c872f2	3	* Copyright (c) 2017-2018, Broadcom Limited. All rights reserved.
cb3c7fd4 GR	4	*
	5	* This software is available to you under a choice of one of two
	6	* licenses. You may choose to be licensed under the terms of the GNU
	7	* General Public License (GPL) Version 2, available from the file
	8	* COPYING in the main directory of this source tree, or the
	9	* OpenIB.org BSD license below:
	10	*
	11	* Redistribution and use in source and binary forms, with or
	12	* without modification, are permitted provided that the following
	13	* conditions are met:
	14	*
	15	* - Redistributions of source code must retain the above
	16	* copyright notice, this list of conditions and the following
	17	* disclaimer.
	18	*
	19	* - Redistributions in binary form must reproduce the above
	20	* copyright notice, this list of conditions and the following
	21	* disclaimer in the documentation and/or other materials
	22	* provided with the distribution.
	23	*
	24	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	25	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	26	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	27	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	28	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	29	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	30	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	31	* SOFTWARE.
	32	*/
	33
4c4dbb4a AG	34	#ifndef NET_DIM_H
	35	#define NET_DIM_H
	36
	37	#include <linux/module.h>
	38
	39	struct net_dim_cq_moder {
	40	u16 usec;
	41	u16 pkts;
	42	u8 cq_period_mode;
	43	};
	44
	45	struct net_dim_sample {
	46	ktime_t time;
	47	u32 pkt_ctr;
	48	u32 byte_ctr;
	49	u16 event_ctr;
	50	};
	51
	52	struct net_dim_stats {
	53	int ppms; /* packets per msec */
	54	int bpms; /* bytes per msec */
	55	int epms; /* events per msec */
	56	};
	57
	58	struct net_dim { /* Adaptive Moderation */
	59	u8 state;
	60	struct net_dim_stats prev_stats;
	61	struct net_dim_sample start_sample;
	62	struct work_struct work;
	63	u8 profile_ix;
	64	u8 mode;
	65	u8 tune_state;
	66	u8 steps_right;
	67	u8 steps_left;
	68	u8 tired;
	69	};
	70
	71	enum {
	72	NET_DIM_CQ_PERIOD_MODE_START_FROM_EQE = 0x0,
	73	NET_DIM_CQ_PERIOD_MODE_START_FROM_CQE = 0x1,
	74	NET_DIM_CQ_PERIOD_NUM_MODES
	75	};
	76
	77	/* Adaptive moderation logic */
	78	enum {
	79	NET_DIM_START_MEASURE,
	80	NET_DIM_MEASURE_IN_PROGRESS,
	81	NET_DIM_APPLY_NEW_PROFILE,
	82	};
	83
	84	enum {
	85	NET_DIM_PARKING_ON_TOP,
	86	NET_DIM_PARKING_TIRED,
	87	NET_DIM_GOING_RIGHT,
	88	NET_DIM_GOING_LEFT,
	89	};
	90
	91	enum {
	92	NET_DIM_STATS_WORSE,
	93	NET_DIM_STATS_SAME,
	94	NET_DIM_STATS_BETTER,
	95	};
	96
	97	enum {
98	NET_DIM_STEPPED,
99	NET_DIM_TOO_TIRED,
100	NET_DIM_ON_EDGE,
101	};
cb3c7fd4	102
9a317425	103	#define NET_DIM_PARAMS_NUM_PROFILES 5
cb3c7fd4	104	/* Adaptive moderation profiles */
9a317425	105	#define NET_DIM_DEFAULT_RX_CQ_MODERATION_PKTS_FROM_EQE 256
623ad755	106	#define NET_DIM_DEFAULT_TX_CQ_MODERATION_PKTS_FROM_EQE 128
9a317425 AG	107	#define NET_DIM_DEF_PROFILE_CQE 1
	108	#define NET_DIM_DEF_PROFILE_EQE 1
	109
	110	/* All profiles sizes must be NET_PARAMS_DIM_NUM_PROFILES */
623ad755	111	#define NET_DIM_RX_EQE_PROFILES { \
9a317425 AG	112	{1, NET_DIM_DEFAULT_RX_CQ_MODERATION_PKTS_FROM_EQE}, \
	113	{8, NET_DIM_DEFAULT_RX_CQ_MODERATION_PKTS_FROM_EQE}, \
	114	{64, NET_DIM_DEFAULT_RX_CQ_MODERATION_PKTS_FROM_EQE}, \
	115	{128, NET_DIM_DEFAULT_RX_CQ_MODERATION_PKTS_FROM_EQE}, \
	116	{256, NET_DIM_DEFAULT_RX_CQ_MODERATION_PKTS_FROM_EQE}, \
cb3c7fd4 GR	117	}
cb3c7fd4 GR	118
623ad755	119	#define NET_DIM_RX_CQE_PROFILES { \
cb3c7fd4 GR	120	{2, 256}, \
	121	{8, 128}, \
	122	{16, 64}, \
	123	{32, 64}, \
	124	{64, 64} \
	125	}
	126
623ad755 TG	127	#define NET_DIM_TX_EQE_PROFILES { \
	128	{1, NET_DIM_DEFAULT_TX_CQ_MODERATION_PKTS_FROM_EQE}, \
	129	{8, NET_DIM_DEFAULT_TX_CQ_MODERATION_PKTS_FROM_EQE}, \
	130	{32, NET_DIM_DEFAULT_TX_CQ_MODERATION_PKTS_FROM_EQE}, \
	131	{64, NET_DIM_DEFAULT_TX_CQ_MODERATION_PKTS_FROM_EQE}, \
	132	{128, NET_DIM_DEFAULT_TX_CQ_MODERATION_PKTS_FROM_EQE} \
	133	}
	134
	135	#define NET_DIM_TX_CQE_PROFILES { \
	136	{5, 128}, \
	137	{8, 64}, \
	138	{16, 32}, \
	139	{32, 32}, \
	140	{64, 32} \
	141	}
	142
9a317425	143	static const struct net_dim_cq_moder
623ad755 TG	144	rx_profile[NET_DIM_CQ_PERIOD_NUM_MODES][NET_DIM_PARAMS_NUM_PROFILES] = {
	145	NET_DIM_RX_EQE_PROFILES,
	146	NET_DIM_RX_CQE_PROFILES,
	147	};
	148
	149	static const struct net_dim_cq_moder
	150	tx_profile[NET_DIM_CQ_PERIOD_NUM_MODES][NET_DIM_PARAMS_NUM_PROFILES] = {
	151	NET_DIM_TX_EQE_PROFILES,
	152	NET_DIM_TX_CQE_PROFILES,
cb3c7fd4 GR	153	};
cb3c7fd4 GR	154
026a807c TG	155	static inline struct net_dim_cq_moder
026a807c TG	156	net_dim_get_rx_moderation(u8 cq_period_mode, int ix)
cb3c7fd4	157	{
623ad755	158	struct net_dim_cq_moder cq_moder = rx_profile[cq_period_mode][ix];
0088cbbc	159
0088cbbc TG	160	cq_moder.cq_period_mode = cq_period_mode;
0088cbbc TG	161	return cq_moder;
cb3c7fd4 GR	162	}
cb3c7fd4 GR	163
026a807c	164	static inline struct net_dim_cq_moder
623ad755 TG	165	net_dim_get_def_rx_moderation(u8 cq_period_mode)
	166	{
	167	u8 profile_ix = cq_period_mode == NET_DIM_CQ_PERIOD_MODE_START_FROM_CQE ?
	168	NET_DIM_DEF_PROFILE_CQE : NET_DIM_DEF_PROFILE_EQE;
	169
	170	return net_dim_get_rx_moderation(cq_period_mode, profile_ix);
	171	}
	172
	173	static inline struct net_dim_cq_moder
	174	net_dim_get_tx_moderation(u8 cq_period_mode, int ix)
cb3c7fd4	175	{
623ad755	176	struct net_dim_cq_moder cq_moder = tx_profile[cq_period_mode][ix];
cb3c7fd4	177
623ad755 TG	178	cq_moder.cq_period_mode = cq_period_mode;
	179	return cq_moder;
	180	}
	181
	182	static inline struct net_dim_cq_moder
	183	net_dim_get_def_tx_moderation(u8 cq_period_mode)
	184	{
	185	u8 profile_ix = cq_period_mode == NET_DIM_CQ_PERIOD_MODE_START_FROM_CQE ?
	186	NET_DIM_DEF_PROFILE_CQE : NET_DIM_DEF_PROFILE_EQE;
cb3c7fd4	187
623ad755	188	return net_dim_get_tx_moderation(cq_period_mode, profile_ix);
cb3c7fd4 GR	189	}
cb3c7fd4 GR	190
4c4dbb4a	191	static inline bool net_dim_on_top(struct net_dim *dim)
cb3c7fd4	192	{
9a317425 AG	193	switch (dim->tune_state) {
	194	case NET_DIM_PARKING_ON_TOP:
	195	case NET_DIM_PARKING_TIRED:
cb3c7fd4	196	return true;
9a317425 AG	197	case NET_DIM_GOING_RIGHT:
	198	return (dim->steps_left > 1) && (dim->steps_right == 1);
	199	default: /* NET_DIM_GOING_LEFT */
	200	return (dim->steps_right > 1) && (dim->steps_left == 1);
cb3c7fd4 GR	201	}
	202	}
	203
4c4dbb4a	204	static inline void net_dim_turn(struct net_dim *dim)
cb3c7fd4	205	{
9a317425 AG	206	switch (dim->tune_state) {
	207	case NET_DIM_PARKING_ON_TOP:
	208	case NET_DIM_PARKING_TIRED:
cb3c7fd4	209	break;
9a317425 AG	210	case NET_DIM_GOING_RIGHT:
	211	dim->tune_state = NET_DIM_GOING_LEFT;
	212	dim->steps_left = 0;
cb3c7fd4	213	break;
9a317425 AG	214	case NET_DIM_GOING_LEFT:
	215	dim->tune_state = NET_DIM_GOING_RIGHT;
	216	dim->steps_right = 0;
cb3c7fd4 GR	217	break;
	218	}
	219	}
	220
4c4dbb4a	221	static inline int net_dim_step(struct net_dim *dim)
cb3c7fd4	222	{
9a317425 AG	223	if (dim->tired == (NET_DIM_PARAMS_NUM_PROFILES * 2))
9a317425 AG	224	return NET_DIM_TOO_TIRED;
cb3c7fd4	225
9a317425 AG	226	switch (dim->tune_state) {
	227	case NET_DIM_PARKING_ON_TOP:
	228	case NET_DIM_PARKING_TIRED:
cb3c7fd4	229	break;
9a317425 AG	230	case NET_DIM_GOING_RIGHT:
	231	if (dim->profile_ix == (NET_DIM_PARAMS_NUM_PROFILES - 1))
	232	return NET_DIM_ON_EDGE;
	233	dim->profile_ix++;
	234	dim->steps_right++;
cb3c7fd4	235	break;
9a317425 AG	236	case NET_DIM_GOING_LEFT:
	237	if (dim->profile_ix == 0)
	238	return NET_DIM_ON_EDGE;
	239	dim->profile_ix--;
	240	dim->steps_left++;
cb3c7fd4 GR	241	break;
	242	}
	243
9a317425 AG	244	dim->tired++;
9a317425 AG	245	return NET_DIM_STEPPED;
cb3c7fd4 GR	246	}
cb3c7fd4 GR	247
4c4dbb4a	248	static inline void net_dim_park_on_top(struct net_dim *dim)
cb3c7fd4	249	{
9a317425 AG	250	dim->steps_right = 0;
	251	dim->steps_left = 0;
	252	dim->tired = 0;
	253	dim->tune_state = NET_DIM_PARKING_ON_TOP;
cb3c7fd4 GR	254	}
cb3c7fd4 GR	255
4c4dbb4a	256	static inline void net_dim_park_tired(struct net_dim *dim)
cb3c7fd4	257	{
9a317425 AG	258	dim->steps_right = 0;
	259	dim->steps_left = 0;
	260	dim->tune_state = NET_DIM_PARKING_TIRED;
cb3c7fd4 GR	261	}
cb3c7fd4 GR	262
4c4dbb4a	263	static inline void net_dim_exit_parking(struct net_dim *dim)
cb3c7fd4	264	{
9a317425 AG	265	dim->tune_state = dim->profile_ix ? NET_DIM_GOING_LEFT :
	266	NET_DIM_GOING_RIGHT;
	267	net_dim_step(dim);
cb3c7fd4 GR	268	}
cb3c7fd4 GR	269
c3164d2f	270	#define IS_SIGNIFICANT_DIFF(val, ref) \
f97c3dc3	271	(((100UL * abs((val) - (ref))) / (ref)) > 10) /* more than 10% difference */
c3164d2f	272
4c4dbb4a AG	273	static inline int net_dim_stats_compare(struct net_dim_stats *curr,
4c4dbb4a AG	274	struct net_dim_stats *prev)
cb3c7fd4	275	{
c3164d2f	276	if (!prev->bpms)
9a317425 AG	277	return curr->bpms ? NET_DIM_STATS_BETTER :
9a317425 AG	278	NET_DIM_STATS_SAME;
cb3c7fd4	279
c3164d2f	280	if (IS_SIGNIFICANT_DIFF(curr->bpms, prev->bpms))
9a317425 AG	281	return (curr->bpms > prev->bpms) ? NET_DIM_STATS_BETTER :
9a317425 AG	282	NET_DIM_STATS_WORSE;
cb3c7fd4	283
5165674f TB	284	if (!prev->ppms)
	285	return curr->ppms ? NET_DIM_STATS_BETTER :
	286	NET_DIM_STATS_SAME;
	287
c3164d2f	288	if (IS_SIGNIFICANT_DIFF(curr->ppms, prev->ppms))
9a317425 AG	289	return (curr->ppms > prev->ppms) ? NET_DIM_STATS_BETTER :
9a317425 AG	290	NET_DIM_STATS_WORSE;
cb3c7fd4	291
5165674f TB	292	if (!prev->epms)
	293	return NET_DIM_STATS_SAME;
	294
c3164d2f	295	if (IS_SIGNIFICANT_DIFF(curr->epms, prev->epms))
9a317425 AG	296	return (curr->epms < prev->epms) ? NET_DIM_STATS_BETTER :
9a317425 AG	297	NET_DIM_STATS_WORSE;
cb3c7fd4	298
9a317425	299	return NET_DIM_STATS_SAME;
cb3c7fd4 GR	300	}
cb3c7fd4 GR	301
4c4dbb4a AG	302	static inline bool net_dim_decision(struct net_dim_stats *curr_stats,
4c4dbb4a AG	303	struct net_dim *dim)
cb3c7fd4	304	{
9a317425 AG	305	int prev_state = dim->tune_state;
9a317425 AG	306	int prev_ix = dim->profile_ix;
cb3c7fd4 GR	307	int stats_res;
	308	int step_res;
	309
9a317425 AG	310	switch (dim->tune_state) {
	311	case NET_DIM_PARKING_ON_TOP:
	312	stats_res = net_dim_stats_compare(curr_stats, &dim->prev_stats);
	313	if (stats_res != NET_DIM_STATS_SAME)
	314	net_dim_exit_parking(dim);
cb3c7fd4 GR	315	break;
cb3c7fd4 GR	316
9a317425 AG	317	case NET_DIM_PARKING_TIRED:
	318	dim->tired--;
	319	if (!dim->tired)
	320	net_dim_exit_parking(dim);
cb3c7fd4 GR	321	break;
cb3c7fd4 GR	322
9a317425 AG	323	case NET_DIM_GOING_RIGHT:
	324	case NET_DIM_GOING_LEFT:
	325	stats_res = net_dim_stats_compare(curr_stats, &dim->prev_stats);
	326	if (stats_res != NET_DIM_STATS_BETTER)
	327	net_dim_turn(dim);
cb3c7fd4	328
9a317425 AG	329	if (net_dim_on_top(dim)) {
9a317425 AG	330	net_dim_park_on_top(dim);
cb3c7fd4 GR	331	break;
	332	}
	333
9a317425	334	step_res = net_dim_step(dim);
cb3c7fd4	335	switch (step_res) {
9a317425 AG	336	case NET_DIM_ON_EDGE:
9a317425 AG	337	net_dim_park_on_top(dim);
cb3c7fd4	338	break;
9a317425 AG	339	case NET_DIM_TOO_TIRED:
9a317425 AG	340	net_dim_park_tired(dim);
cb3c7fd4 GR	341	break;
	342	}
	343
	344	break;
	345	}
	346
9a317425 AG	347	if ((prev_state != NET_DIM_PARKING_ON_TOP) \|\|
	348	(dim->tune_state != NET_DIM_PARKING_ON_TOP))
	349	dim->prev_stats = *curr_stats;
cb3c7fd4	350
9a317425	351	return dim->profile_ix != prev_ix;
cb3c7fd4 GR	352	}
cb3c7fd4 GR	353
4c4dbb4a AG	354	static inline void net_dim_sample(u16 event_ctr,
	355	u64 packets,
	356	u64 bytes,
	357	struct net_dim_sample *s)
cb3c7fd4 GR	358	{
cb3c7fd4 GR	359	s->time = ktime_get();
138968e9 AG	360	s->pkt_ctr = packets;
	361	s->byte_ctr = bytes;
	362	s->event_ctr = event_ctr;
cb3c7fd4 GR	363	}
cb3c7fd4 GR	364
9a317425	365	#define NET_DIM_NEVENTS 64
53acd76c	366	#define BIT_GAP(bits, end, start) ((((end) - (start)) + BIT_ULL(bits)) & (BIT_ULL(bits) - 1))
cb3c7fd4	367
4c4dbb4a AG	368	static inline void net_dim_calc_stats(struct net_dim_sample *start,
	369	struct net_dim_sample *end,
	370	struct net_dim_stats *curr_stats)
cb3c7fd4 GR	371	{
	372	/* u32 holds up to 71 minutes, should be enough */
	373	u32 delta_us = ktime_us_delta(end->time, start->time);
53acd76c TG	374	u32 npkts = BIT_GAP(BITS_PER_TYPE(u32), end->pkt_ctr, start->pkt_ctr);
	375	u32 nbytes = BIT_GAP(BITS_PER_TYPE(u32), end->byte_ctr,
	376	start->byte_ctr);
cb3c7fd4	377
0bbcc0a8	378	if (!delta_us)
cb3c7fd4	379	return;
cb3c7fd4	380
c3164d2f TG	381	curr_stats->ppms = DIV_ROUND_UP(npkts * USEC_PER_MSEC, delta_us);
c3164d2f TG	382	curr_stats->bpms = DIV_ROUND_UP(nbytes * USEC_PER_MSEC, delta_us);
9a317425	383	curr_stats->epms = DIV_ROUND_UP(NET_DIM_NEVENTS * USEC_PER_MSEC,
c3164d2f	384	delta_us);
cb3c7fd4 GR	385	}
cb3c7fd4 GR	386
4c4dbb4a	387	static inline void net_dim(struct net_dim *dim,
8115b750	388	struct net_dim_sample end_sample)
cb3c7fd4	389	{
9a317425	390	struct net_dim_stats curr_stats;
cb3c7fd4 GR	391	u16 nevents;
cb3c7fd4 GR	392
9a317425 AG	393	switch (dim->state) {
9a317425 AG	394	case NET_DIM_MEASURE_IN_PROGRESS:
8115b750 AG	395	nevents = BIT_GAP(BITS_PER_TYPE(u16),
8115b750 AG	396	end_sample.event_ctr,
9a317425 AG	397	dim->start_sample.event_ctr);
9a317425 AG	398	if (nevents < NET_DIM_NEVENTS)
cb3c7fd4	399	break;
9a317425 AG	400	net_dim_calc_stats(&dim->start_sample, &end_sample,
	401	&curr_stats);
	402	if (net_dim_decision(&curr_stats, dim)) {
	403	dim->state = NET_DIM_APPLY_NEW_PROFILE;
	404	schedule_work(&dim->work);
cb3c7fd4 GR	405	break;
	406	}
	407	/* fall through */
9a317425	408	case NET_DIM_START_MEASURE:
0211dda6 TG	409	net_dim_sample(end_sample.event_ctr, end_sample.pkt_ctr, end_sample.byte_ctr,
0211dda6 TG	410	&dim->start_sample);
9a317425	411	dim->state = NET_DIM_MEASURE_IN_PROGRESS;
cb3c7fd4	412	break;
9a317425	413	case NET_DIM_APPLY_NEW_PROFILE:
cb3c7fd4 GR	414	break;
	415	}
	416	}
4c4dbb4a AG	417
4c4dbb4a AG	418	#endif /* NET_DIM_H */