// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
/*
* Copyright (c) 2018, Mellanox Technologies inc. All rights reserved.
*/
#include <linux/dim.h>
#include <linux/rtnetlink.h>
/*
* Net DIM profiles:
* There are different set of profiles for each CQ period mode.
* There are different set of profiles for RX/TX CQs.
* Each profile size must be of NET_DIM_PARAMS_NUM_PROFILES
*/
#define NET_DIM_RX_EQE_PROFILES { \
{.usec = 1, .pkts = NET_DIM_DEFAULT_RX_CQ_PKTS_FROM_EQE,}, \
{.usec = 8, .pkts = NET_DIM_DEFAULT_RX_CQ_PKTS_FROM_EQE,}, \
{.usec = 64, .pkts = NET_DIM_DEFAULT_RX_CQ_PKTS_FROM_EQE,}, \
{.usec = 128, .pkts = NET_DIM_DEFAULT_RX_CQ_PKTS_FROM_EQE,}, \
{.usec = 256, .pkts = NET_DIM_DEFAULT_RX_CQ_PKTS_FROM_EQE,} \
}
#define NET_DIM_RX_CQE_PROFILES { \
{.usec = 2, .pkts = 256,}, \
{.usec = 8, .pkts = 128,}, \
{.usec = 16, .pkts = 64,}, \
{.usec = 32, .pkts = 64,}, \
{.usec = 64, .pkts = 64,} \
}
#define NET_DIM_TX_EQE_PROFILES { \
{.usec = 1, .pkts = NET_DIM_DEFAULT_TX_CQ_PKTS_FROM_EQE,}, \
{.usec = 8, .pkts = NET_DIM_DEFAULT_TX_CQ_PKTS_FROM_EQE,}, \
{.usec = 32, .pkts = NET_DIM_DEFAULT_TX_CQ_PKTS_FROM_EQE,}, \
{.usec = 64, .pkts = NET_DIM_DEFAULT_TX_CQ_PKTS_FROM_EQE,}, \
{.usec = 128, .pkts = NET_DIM_DEFAULT_TX_CQ_PKTS_FROM_EQE,} \
}
#define NET_DIM_TX_CQE_PROFILES { \
{.usec = 5, .pkts = 128,}, \
{.usec = 8, .pkts = 64,}, \
{.usec = 16, .pkts = 32,}, \
{.usec = 32, .pkts = 32,}, \
{.usec = 64, .pkts = 32,} \
}
static const struct dim_cq_moder
rx_profile[DIM_CQ_PERIOD_NUM_MODES][NET_DIM_PARAMS_NUM_PROFILES] = {
NET_DIM_RX_EQE_PROFILES,
NET_DIM_RX_CQE_PROFILES,
};
static const struct dim_cq_moder
tx_profile[DIM_CQ_PERIOD_NUM_MODES][NET_DIM_PARAMS_NUM_PROFILES] = {
NET_DIM_TX_EQE_PROFILES,
NET_DIM_TX_CQE_PROFILES,
};
struct dim_cq_moder
net_dim_get_rx_moderation(u8 cq_period_mode, int ix)
{
struct dim_cq_moder cq_moder = rx_profile[cq_period_mode][ix];
cq_moder.cq_period_mode = cq_period_mode;
return cq_moder;
}
EXPORT_SYMBOL(net_dim_get_rx_moderation);
struct dim_cq_moder
net_dim_get_def_rx_moderation(u8 cq_period_mode)
{
u8 profile_ix = cq_period_mode == 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);
}
EXPORT_SYMBOL(net_dim_get_def_rx_moderation);
struct dim_cq_moder
net_dim_get_tx_moderation(u8 cq_period_mode, int ix)
{
struct dim_cq_moder cq_moder = tx_profile[cq_period_mode][ix];
cq_moder.cq_period_mode = cq_period_mode;
return cq_moder;
}
EXPORT_SYMBOL(net_dim_get_tx_moderation);
struct dim_cq_moder
net_dim_get_def_tx_moderation(u8 cq_period_mode)
{
u8 profile_ix = cq_period_mode == 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);
}
EXPORT_SYMBOL(net_dim_get_def_tx_moderation);
int net_dim_init_irq_moder(struct net_device *dev, u8 profile_flags,
u8 coal_flags, u8 rx_mode, u8 tx_mode,
void (*rx_dim_work)(struct work_struct *work),
void (*tx_dim_work)(struct work_struct *work))
{
struct dim_cq_moder *rxp = NULL, *txp;
struct dim_irq_moder *moder;
int len;
dev->irq_moder = kzalloc(sizeof(*dev->irq_moder), GFP_KERNEL);
if (!dev->irq_moder)
return -ENOMEM;
moder = dev->irq_moder;
len = NET_DIM_PARAMS_NUM_PROFILES * sizeof(*moder->rx_profile);
moder->coal_flags = coal_flags;
moder->profile_flags = profile_flags;
if (profile_flags & DIM_PROFILE_RX) {
moder->rx_dim_work = rx_dim_work;
moder->dim_rx_mode = rx_mode;
rxp = kmemdup(rx_profile[rx_mode], len, GFP_KERNEL);
if (!rxp)
goto free_moder;
rcu_assign_pointer(moder->rx_profile, rxp);
}
if (profile_flags & DIM_PROFILE_TX) {
moder->tx_dim_work = tx_dim_work;
moder->dim_tx_mode = tx_mode;
txp = kmemdup(tx_profile[tx_mode], len, GFP_KERNEL);
if (!txp)
goto free_rxp;
rcu_assign_pointer(moder->tx_profile, txp);
}
return 0;
free_rxp:
kfree(rxp);
free_moder:
kfree(moder);
return -ENOMEM;
}
EXPORT_SYMBOL(net_dim_init_irq_moder);
/* RTNL lock is held. */
void net_dim_free_irq_moder(struct net_device *dev)
{
struct dim_cq_moder *rxp, *txp;
if (!dev->irq_moder)
return;
rxp = rtnl_dereference(dev->irq_moder->rx_profile);
txp = rtnl_dereference(dev->irq_moder->tx_profile);
rcu_assign_pointer(dev->irq_moder->rx_profile, NULL);
rcu_assign_pointer(dev->irq_moder->tx_profile, NULL);
kfree_rcu(rxp, rcu);
kfree_rcu(txp, rcu);
kfree(dev->irq_moder);
}
EXPORT_SYMBOL(net_dim_free_irq_moder);
void net_dim_setting(struct net_device *dev, struct dim *dim, bool is_tx)
{
struct dim_irq_moder *irq_moder = dev->irq_moder;
if (!irq_moder)
return;
if (is_tx) {
INIT_WORK(&dim->work, irq_moder->tx_dim_work);
dim->mode = READ_ONCE(irq_moder->dim_tx_mode);
return;
}
INIT_WORK(&dim->work, irq_moder->rx_dim_work);
dim->mode = READ_ONCE(irq_moder->dim_rx_mode);
}
EXPORT_SYMBOL(net_dim_setting);
void net_dim_work_cancel(struct dim *dim)
{
cancel_work_sync(&dim->work);
}
EXPORT_SYMBOL(net_dim_work_cancel);
struct dim_cq_moder net_dim_get_rx_irq_moder(struct net_device *dev,
struct dim *dim)
{
struct dim_cq_moder res, *profile;
rcu_read_lock();
profile = rcu_dereference(dev->irq_moder->rx_profile);
res = profile[dim->profile_ix];
rcu_read_unlock();
res.cq_period_mode = dim->mode;
return res;
}
EXPORT_SYMBOL(net_dim_get_rx_irq_moder);
struct dim_cq_moder net_dim_get_tx_irq_moder(struct net_device *dev,
struct dim *dim)
{
struct dim_cq_moder res, *profile;
rcu_read_lock();
profile = rcu_dereference(dev->irq_moder->tx_profile);
res = profile[dim->profile_ix];
rcu_read_unlock();
res.cq_period_mode = dim->mode;
return res;
}
EXPORT_SYMBOL(net_dim_get_tx_irq_moder);
void net_dim_set_rx_mode(struct net_device *dev, u8 rx_mode)
{
WRITE_ONCE(dev->irq_moder->dim_rx_mode, rx_mode);
}
EXPORT_SYMBOL(net_dim_set_rx_mode);
void net_dim_set_tx_mode(struct net_device *dev, u8 tx_mode)
{
WRITE_ONCE(dev->irq_moder->dim_tx_mode, tx_mode);
}
EXPORT_SYMBOL(net_dim_set_tx_mode);
static int net_dim_step(struct dim *dim)
{
if (dim->tired == (NET_DIM_PARAMS_NUM_PROFILES * 2))
return DIM_TOO_TIRED;
switch (dim->tune_state) {
case DIM_PARKING_ON_TOP:
case DIM_PARKING_TIRED:
break;
case DIM_GOING_RIGHT:
if (dim->profile_ix == (NET_DIM_PARAMS_NUM_PROFILES - 1))
return DIM_ON_EDGE;
dim->profile_ix++;
dim->steps_right++;
break;
case DIM_GOING_LEFT:
if (dim->profile_ix == 0)
return DIM_ON_EDGE;
dim->profile_ix--;
dim->steps_left++;
break;
}
dim->tired++;
return DIM_STEPPED;
}
static void net_dim_exit_parking(struct dim *dim)
{
dim->tune_state = dim->profile_ix ? DIM_GOING_LEFT : DIM_GOING_RIGHT;
net_dim_step(dim);
}
static int net_dim_stats_compare(struct dim_stats *curr,
struct dim_stats *prev)
{
if (!prev->bpms)
return curr->bpms ? DIM_STATS_BETTER : DIM_STATS_SAME;
if (IS_SIGNIFICANT_DIFF(curr->bpms, prev->bpms))
return (curr->bpms > prev->bpms) ? DIM_STATS_BETTER :
DIM_STATS_WORSE;
if (!prev->ppms)
return curr->ppms ? DIM_STATS_BETTER :
DIM_STATS_SAME;
if (IS_SIGNIFICANT_DIFF(curr->ppms, prev->ppms))
return (curr->ppms > prev->ppms) ? DIM_STATS_BETTER :
DIM_STATS_WORSE;
if (!prev->epms)
return DIM_STATS_SAME;
if (IS_SIGNIFICANT_DIFF(curr->epms, prev->epms))
return (curr->epms < prev->epms) ? DIM_STATS_BETTER :
DIM_STATS_WORSE;
return DIM_STATS_SAME;
}
static bool net_dim_decision(struct dim_stats *curr_stats, struct 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 DIM_PARKING_ON_TOP:
stats_res = net_dim_stats_compare(curr_stats,
&dim->prev_stats);
if (stats_res != DIM_STATS_SAME)
net_dim_exit_parking(dim);
break;
case DIM_PARKING_TIRED:
dim->tired--;
if (!dim->tired)
net_dim_exit_parking(dim);
break;
case DIM_GOING_RIGHT:
case DIM_GOING_LEFT:
stats_res = net_dim_stats_compare(curr_stats,
&dim->prev_stats);
if (stats_res != DIM_STATS_BETTER)
dim_turn(dim);
if (dim_on_top(dim)) {
dim_park_on_top(dim);
break;
}
step_res = net_dim_step(dim);
switch (step_res) {
case DIM_ON_EDGE:
dim_park_on_top(dim);
break;
case DIM_TOO_TIRED:
dim_park_tired(dim);
break;
}
break;
}
if (prev_state != DIM_PARKING_ON_TOP ||
dim->tune_state != DIM_PARKING_ON_TOP)
dim->prev_stats = *curr_stats;
return dim->profile_ix != prev_ix;
}
void net_dim(struct dim *dim, struct dim_sample end_sample)
{
struct dim_stats curr_stats;
u16 nevents;
switch (dim->state) {
case DIM_MEASURE_IN_PROGRESS:
nevents = BIT_GAP(BITS_PER_TYPE(u16),
end_sample.event_ctr,
dim->start_sample.event_ctr);
if (nevents < DIM_NEVENTS)
break;
if (!dim_calc_stats(&dim->start_sample, &end_sample, &curr_stats))
break;
if (net_dim_decision(&curr_stats, dim)) {
dim->state = DIM_APPLY_NEW_PROFILE;
schedule_work(&dim->work);
break;
}
fallthrough;
case DIM_START_MEASURE:
dim_update_sample(end_sample.event_ctr, end_sample.pkt_ctr,
end_sample.byte_ctr, &dim->start_sample);
dim->state = DIM_MEASURE_IN_PROGRESS;
break;
case DIM_APPLY_NEW_PROFILE:
break;
}
}
EXPORT_SYMBOL(net_dim);