swh:1:snp:c3bf2749e3476071fa748f67b0ffa2fdc5fe49d9
Tip revision: b90cb1053190353cc30f0fef0ef1f378ccc063c5 authored by Linus Torvalds on 28 August 2022, 22:05:29 UTC
Linux 6.0-rc3
Linux 6.0-rc3
Tip revision: b90cb10
net_dim.c
// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
/*
* Copyright (c) 2018, Mellanox Technologies inc. All rights reserved.
*/
#include <linux/dim.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_PARAMS_NUM_PROFILES 5
#define NET_DIM_DEFAULT_RX_CQ_PKTS_FROM_EQE 256
#define NET_DIM_DEFAULT_TX_CQ_PKTS_FROM_EQE 128
#define NET_DIM_DEF_PROFILE_CQE 1
#define NET_DIM_DEF_PROFILE_EQE 1
#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);
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;
dim_calc_stats(&dim->start_sample, &end_sample, &curr_stats);
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);