/*
* Try to increase robustness of max_prob rate by decrease number of
* streams if possible.
*/
static inline void
minstrel_ht_prob_rate_reduce_streams(struct minstrel_ht_sta *mi)
{
struct minstrel_mcs_group_data *mg;
int tmp_max_streams, group, tmp_idx, tmp_prob;
int tmp_tp = 0;
tmp_max_streams = minstrel_mcs_groups[mi->max_tp_rate[0] /
MCS_GROUP_RATES].streams;
for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
mg = &mi->groups[group];
if (!mg->supported || group == MINSTREL_CCK_GROUP)
continue;
tmp_idx = mg->max_group_prob_rate % MCS_GROUP_RATES;
tmp_prob = mi->groups[group].rates[tmp_idx].prob_ewma;
if (tmp_tp < minstrel_ht_get_tp_avg(mi, group, tmp_idx, tmp_prob) &&
(minstrel_mcs_groups[group].streams < tmp_max_streams)) {
mi->max_prob_rate = mg->max_group_prob_rate;
tmp_tp = minstrel_ht_get_tp_avg(mi, group,
tmp_idx,
tmp_prob);
}
}
}
/*
* Assign new rate set per sta and use CCK rates only if the fastest
* rate (max_tp_rate[0]) is from CCK group. This prohibits such sorted
* rate sets where MCS and CCK rates are mixed, because CCK rates can
* not use aggregation.
*/
static void
minstrel_ht_assign_best_tp_rates(struct minstrel_ht_sta *mi,
u16 tmp_mcs_tp_rate[MAX_THR_RATES],
u16 tmp_cck_tp_rate[MAX_THR_RATES])
{
unsigned int tmp_group, tmp_idx, tmp_cck_tp, tmp_mcs_tp, tmp_prob;
int i;
tmp_group = tmp_cck_tp_rate[0] / MCS_GROUP_RATES;
tmp_idx = tmp_cck_tp_rate[0] % MCS_GROUP_RATES;
tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma;
tmp_cck_tp = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob);
tmp_group = tmp_mcs_tp_rate[0] / MCS_GROUP_RATES;
tmp_idx = tmp_mcs_tp_rate[0] % MCS_GROUP_RATES;
tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma;
tmp_mcs_tp = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob);
if (tmp_cck_tp > tmp_mcs_tp) {
for(i = 0; i < MAX_THR_RATES; i++) {
minstrel_ht_sort_best_tp_rates(mi, tmp_cck_tp_rate[i],
tmp_mcs_tp_rate);
}
}
}
/*
* Find & sort topmost throughput rates
*
* If multiple rates provide equal throughput the sorting is based on their
* current success probability. Higher success probability is preferred among
* MCS groups, CCK rates do not provide aggregation and are therefore at last.
*/
static void
minstrel_ht_sort_best_tp_rates(struct minstrel_ht_sta *mi, u16 index,
u16 *tp_list)
{
int cur_group, cur_idx, cur_tp_avg, cur_prob;
int tmp_group, tmp_idx, tmp_tp_avg, tmp_prob;
int j = MAX_THR_RATES;
cur_group = index / MCS_GROUP_RATES;
cur_idx = index % MCS_GROUP_RATES;
cur_prob = mi->groups[cur_group].rates[cur_idx].prob_ewma;
cur_tp_avg = minstrel_ht_get_tp_avg(mi, cur_group, cur_idx, cur_prob);
do {
tmp_group = tp_list[j - 1] / MCS_GROUP_RATES;
tmp_idx = tp_list[j - 1] % MCS_GROUP_RATES;
tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma;
tmp_tp_avg = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx,
tmp_prob);
if (cur_tp_avg < tmp_tp_avg ||
(cur_tp_avg == tmp_tp_avg && cur_prob <= tmp_prob))
break;
j--;
} while (j > 0);
if (j < MAX_THR_RATES - 1) {
memmove(&tp_list[j + 1], &tp_list[j], (sizeof(*tp_list) *
(MAX_THR_RATES - (j + 1))));
}
if (j < MAX_THR_RATES)
tp_list[j] = index;
}
/*
* Find and set the topmost probability rate per sta and per group
*/
static void
minstrel_ht_set_best_prob_rate(struct minstrel_ht_sta *mi, u16 index)
{
struct minstrel_mcs_group_data *mg;
struct minstrel_rate_stats *mrs;
int tmp_group, tmp_idx, tmp_tp_avg, tmp_prob;
int max_tp_group, cur_tp_avg, cur_group, cur_idx;
int max_gpr_group, max_gpr_idx;
int max_gpr_tp_avg, max_gpr_prob;
cur_group = index / MCS_GROUP_RATES;
cur_idx = index % MCS_GROUP_RATES;
mg = &mi->groups[index / MCS_GROUP_RATES];
mrs = &mg->rates[index % MCS_GROUP_RATES];
tmp_group = mi->max_prob_rate / MCS_GROUP_RATES;
tmp_idx = mi->max_prob_rate % MCS_GROUP_RATES;
tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma;
tmp_tp_avg = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob);
/* if max_tp_rate[0] is from MCS_GROUP max_prob_rate get selected from
* MCS_GROUP as well as CCK_GROUP rates do not allow aggregation */
max_tp_group = mi->max_tp_rate[0] / MCS_GROUP_RATES;
if((index / MCS_GROUP_RATES == MINSTREL_CCK_GROUP) &&
(max_tp_group != MINSTREL_CCK_GROUP))
return;
max_gpr_group = mg->max_group_prob_rate / MCS_GROUP_RATES;
max_gpr_idx = mg->max_group_prob_rate % MCS_GROUP_RATES;
max_gpr_prob = mi->groups[max_gpr_group].rates[max_gpr_idx].prob_ewma;
if (mrs->prob_ewma > MINSTREL_FRAC(75, 100)) {
cur_tp_avg = minstrel_ht_get_tp_avg(mi, cur_group, cur_idx,
mrs->prob_ewma);
if (cur_tp_avg > tmp_tp_avg)
mi->max_prob_rate = index;
max_gpr_tp_avg = minstrel_ht_get_tp_avg(mi, max_gpr_group,
max_gpr_idx,
max_gpr_prob);
if (cur_tp_avg > max_gpr_tp_avg)
mg->max_group_prob_rate = index;
} else {
if (mrs->prob_ewma > tmp_prob)
mi->max_prob_rate = index;
if (mrs->prob_ewma > max_gpr_prob)
mg->max_group_prob_rate = index;
}
}
/*
* Update rate statistics and select new primary rates
*
* Rules for rate selection:
* - max_prob_rate must use only one stream, as a tradeoff between delivery
* probability and throughput during strong fluctuations
* - as long as the max prob rate has a probability of more than 75%, pick
* higher throughput rates, even if the probablity is a bit lower
*/
static void
minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
{
struct minstrel_mcs_group_data *mg;
struct minstrel_rate_stats *mrs;
int group, i, j, cur_prob;
u16 tmp_mcs_tp_rate[MAX_THR_RATES], tmp_group_tp_rate[MAX_THR_RATES];
u16 tmp_cck_tp_rate[MAX_THR_RATES], index;
if (mi->ampdu_packets > 0) {
mi->avg_ampdu_len = minstrel_ewma(mi->avg_ampdu_len,
MINSTREL_FRAC(mi->ampdu_len, mi->ampdu_packets), EWMA_LEVEL);
mi->ampdu_len = 0;
mi->ampdu_packets = 0;
}
mi->sample_slow = 0;
mi->sample_count = 0;
/* Initialize global rate indexes */
for(j = 0; j < MAX_THR_RATES; j++){
tmp_mcs_tp_rate[j] = 0;
tmp_cck_tp_rate[j] = 0;
}
/* Find best rate sets within all MCS groups*/
for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
mg = &mi->groups[group];
if (!mg->supported)
continue;
mi->sample_count++;
/* (re)Initialize group rate indexes */
for(j = 0; j < MAX_THR_RATES; j++)
tmp_group_tp_rate[j] = group;
for (i = 0; i < MCS_GROUP_RATES; i++) {
if (!(mg->supported & BIT(i)))
continue;
index = MCS_GROUP_RATES * group + i;
mrs = &mg->rates[i];
mrs->retry_updated = false;
minstrel_calc_rate_stats(mrs);
cur_prob = mrs->prob_ewma;
if (minstrel_ht_get_tp_avg(mi, group, i, cur_prob) == 0)
continue;
/* Find max throughput rate set */
if (group != MINSTREL_CCK_GROUP) {
minstrel_ht_sort_best_tp_rates(mi, index,
tmp_mcs_tp_rate);
} else if (group == MINSTREL_CCK_GROUP) {
minstrel_ht_sort_best_tp_rates(mi, index,
tmp_cck_tp_rate);
}
/* Find max throughput rate set within a group */
minstrel_ht_sort_best_tp_rates(mi, index,
tmp_group_tp_rate);
/* Find max probability rate per group and global */
minstrel_ht_set_best_prob_rate(mi, index);
}
memcpy(mg->max_group_tp_rate, tmp_group_tp_rate,
sizeof(mg->max_group_tp_rate));
}
/* Assign new rate set per sta */
minstrel_ht_assign_best_tp_rates(mi, tmp_mcs_tp_rate, tmp_cck_tp_rate);
memcpy(mi->max_tp_rate, tmp_mcs_tp_rate, sizeof(mi->max_tp_rate));
/* Try to increase robustness of max_prob_rate*/
minstrel_ht_prob_rate_reduce_streams(mi);
/* try to sample all available rates during each interval */
mi->sample_count *= 8;
#ifdef CONFIG_MAC80211_DEBUGFS
/* use fixed index if set */
if (mp->fixed_rate_idx != -1) {
for (i = 0; i < 4; i++)
mi->max_tp_rate[i] = mp->fixed_rate_idx;
mi->max_prob_rate = mp->fixed_rate_idx;
}
#endif
/* Reset update timer */
mi->last_stats_update = jiffies;
}
static char *
minstrel_ht_stats_dump(struct minstrel_ht_sta *mi, int i, char *p)
{
const struct mcs_group *mg;
unsigned int j, tp_max, tp_avg, eprob, tx_time;
char htmode = '2';
char gimode = 'L';
u32 gflags;
if (!mi->supported[i])
return p;
mg = &minstrel_mcs_groups[i];
gflags = mg->flags;
if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH)
htmode = '4';
else if (gflags & IEEE80211_TX_RC_80_MHZ_WIDTH)
htmode = '8';
if (gflags & IEEE80211_TX_RC_SHORT_GI)
gimode = 'S';
for (j = 0; j < MCS_GROUP_RATES; j++) {
struct minstrel_rate_stats *mrs = &mi->groups[i].rates[j];
static const int bitrates[4] = { 10, 20, 55, 110 };
int idx = i * MCS_GROUP_RATES + j;
unsigned int prob_ewmsd;
if (!(mi->supported[i] & BIT(j)))
continue;
if (gflags & IEEE80211_TX_RC_MCS) {
p += sprintf(p, "HT%c0 ", htmode);
p += sprintf(p, "%cGI ", gimode);
p += sprintf(p, "%d ", mg->streams);
} else if (gflags & IEEE80211_TX_RC_VHT_MCS) {
p += sprintf(p, "VHT%c0 ", htmode);
p += sprintf(p, "%cGI ", gimode);
p += sprintf(p, "%d ", mg->streams);
} else {
p += sprintf(p, "CCK ");
p += sprintf(p, "%cP ", j < 4 ? 'L' : 'S');
p += sprintf(p, "1 ");
}
*(p++) = (idx == mi->max_tp_rate[0]) ? 'A' : ' ';
*(p++) = (idx == mi->max_tp_rate[1]) ? 'B' : ' ';
*(p++) = (idx == mi->max_tp_rate[2]) ? 'C' : ' ';
*(p++) = (idx == mi->max_tp_rate[3]) ? 'D' : ' ';
*(p++) = (idx == mi->max_prob_rate) ? 'P' : ' ';
if (gflags & IEEE80211_TX_RC_MCS) {
p += sprintf(p, " MCS%-2u", (mg->streams - 1) * 8 + j);
} else if (gflags & IEEE80211_TX_RC_VHT_MCS) {
p += sprintf(p, " MCS%-1u/%1u", j, mg->streams);
} else {
int r = bitrates[j % 4];
p += sprintf(p, " %2u.%1uM", r / 10, r % 10);
}
p += sprintf(p, " %3u ", idx);
/* tx_time[rate(i)] in usec */
tx_time = DIV_ROUND_CLOSEST(mg->duration[j], 1000);
p += sprintf(p, "%6u ", tx_time);
tp_max = minstrel_ht_get_tp_avg(mi, i, j, MINSTREL_FRAC(100, 100));
tp_avg = minstrel_ht_get_tp_avg(mi, i, j, mrs->prob_ewma);
eprob = MINSTREL_TRUNC(mrs->prob_ewma * 1000);
prob_ewmsd = minstrel_get_ewmsd10(mrs);
p += sprintf(p, "%4u.%1u %4u.%1u %3u.%1u %3u.%1u"
" %3u %3u %-3u "
"%9llu %-9llu\n",
tp_max / 10, tp_max % 10,
tp_avg / 10, tp_avg % 10,
eprob / 10, eprob % 10,
prob_ewmsd / 10, prob_ewmsd % 10,
mrs->retry_count,
mrs->last_success,
mrs->last_attempts,
(unsigned long long)mrs->succ_hist,
(unsigned long long)mrs->att_hist);
}
return p;
}
static char *
minstrel_ht_stats_csv_dump(struct minstrel_ht_sta *mi, int i, char *p)
{
const struct mcs_group *mg;
unsigned int j, tp_max, tp_avg, eprob, tx_time;
char htmode = '2';
char gimode = 'L';
u32 gflags;
if (!mi->supported[i])
return p;
mg = &minstrel_mcs_groups[i];
gflags = mg->flags;
if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH)
htmode = '4';
else if (gflags & IEEE80211_TX_RC_80_MHZ_WIDTH)
htmode = '8';
if (gflags & IEEE80211_TX_RC_SHORT_GI)
gimode = 'S';
for (j = 0; j < MCS_GROUP_RATES; j++) {
struct minstrel_rate_stats *mrs = &mi->groups[i].rates[j];
static const int bitrates[4] = { 10, 20, 55, 110 };
int idx = i * MCS_GROUP_RATES + j;
unsigned int prob_ewmsd;
if (!(mi->supported[i] & BIT(j)))
continue;
if (gflags & IEEE80211_TX_RC_MCS) {
p += sprintf(p, "HT%c0,", htmode);
p += sprintf(p, "%cGI,", gimode);
p += sprintf(p, "%d,", mg->streams);
} else if (gflags & IEEE80211_TX_RC_VHT_MCS) {
p += sprintf(p, "VHT%c0,", htmode);
p += sprintf(p, "%cGI,", gimode);
p += sprintf(p, "%d,", mg->streams);
} else {
p += sprintf(p, "CCK,");
p += sprintf(p, "%cP,", j < 4 ? 'L' : 'S');
p += sprintf(p, "1,");
}
p += sprintf(p, "%s" ,((idx == mi->max_tp_rate[0]) ? "A" : ""));
p += sprintf(p, "%s" ,((idx == mi->max_tp_rate[1]) ? "B" : ""));
p += sprintf(p, "%s" ,((idx == mi->max_tp_rate[2]) ? "C" : ""));
p += sprintf(p, "%s" ,((idx == mi->max_tp_rate[3]) ? "D" : ""));
p += sprintf(p, "%s" ,((idx == mi->max_prob_rate) ? "P" : ""));
if (gflags & IEEE80211_TX_RC_MCS) {
p += sprintf(p, ",MCS%-2u,", (mg->streams - 1) * 8 + j);
} else if (gflags & IEEE80211_TX_RC_VHT_MCS) {
p += sprintf(p, ",MCS%-1u/%1u,", j, mg->streams);
} else {
int r = bitrates[j % 4];
p += sprintf(p, ",%2u.%1uM,", r / 10, r % 10);
}
p += sprintf(p, "%u,", idx);
tx_time = DIV_ROUND_CLOSEST(mg->duration[j], 1000);
p += sprintf(p, "%u,", tx_time);
tp_max = minstrel_ht_get_tp_avg(mi, i, j, MINSTREL_FRAC(100, 100));
tp_avg = minstrel_ht_get_tp_avg(mi, i, j, mrs->prob_ewma);
eprob = MINSTREL_TRUNC(mrs->prob_ewma * 1000);
prob_ewmsd = minstrel_get_ewmsd10(mrs);
p += sprintf(p, "%u.%u,%u.%u,%u.%u,%u.%u,%u,%u,"
"%u,%llu,%llu,",
tp_max / 10, tp_max % 10,
tp_avg / 10, tp_avg % 10,
eprob / 10, eprob % 10,
prob_ewmsd / 10, prob_ewmsd % 10,
mrs->retry_count,
mrs->last_success,
mrs->last_attempts,
(unsigned long long)mrs->succ_hist,
(unsigned long long)mrs->att_hist);
p += sprintf(p, "%d,%d,%d.%d\n",
max(0, (int) mi->total_packets -
(int) mi->sample_packets),
mi->sample_packets,
MINSTREL_TRUNC(mi->avg_ampdu_len),
MINSTREL_TRUNC(mi->avg_ampdu_len * 10) % 10);
}
return p;
}