From: Felix Fietkau Date: Sat, 10 Feb 2018 12:45:47 +0100 Subject: [PATCH] mac80211: minstrel: reduce minstrel_mcs_groups size By storing a shift value for all duration values of a group, we can reduce precision by a neglegible amount to make it fit into a u16 value. This improves cache footprint and reduces size: Before: text data bss dec hex filename 10024 116 0 10140 279c rc80211_minstrel_ht.o After: text data bss dec hex filename 9368 116 0 9484 250c rc80211_minstrel_ht.o Signed-off-by: Felix Fietkau --- --- a/net/mac80211/rc80211_minstrel_ht.c +++ b/net/mac80211/rc80211_minstrel_ht.c @@ -52,22 +52,23 @@ _streams - 1 /* MCS rate information for an MCS group */ -#define MCS_GROUP(_streams, _sgi, _ht40) \ +#define MCS_GROUP(_streams, _sgi, _ht40, _s) \ [GROUP_IDX(_streams, _sgi, _ht40)] = { \ .streams = _streams, \ + .shift = _s, \ .flags = \ IEEE80211_TX_RC_MCS | \ (_sgi ? IEEE80211_TX_RC_SHORT_GI : 0) | \ (_ht40 ? IEEE80211_TX_RC_40_MHZ_WIDTH : 0), \ .duration = { \ - MCS_DURATION(_streams, _sgi, _ht40 ? 54 : 26), \ - MCS_DURATION(_streams, _sgi, _ht40 ? 108 : 52), \ - MCS_DURATION(_streams, _sgi, _ht40 ? 162 : 78), \ - MCS_DURATION(_streams, _sgi, _ht40 ? 216 : 104), \ - MCS_DURATION(_streams, _sgi, _ht40 ? 324 : 156), \ - MCS_DURATION(_streams, _sgi, _ht40 ? 432 : 208), \ - MCS_DURATION(_streams, _sgi, _ht40 ? 486 : 234), \ - MCS_DURATION(_streams, _sgi, _ht40 ? 540 : 260) \ + MCS_DURATION(_streams, _sgi, _ht40 ? 54 : 26) >> _s, \ + MCS_DURATION(_streams, _sgi, _ht40 ? 108 : 52) >> _s, \ + MCS_DURATION(_streams, _sgi, _ht40 ? 162 : 78) >> _s, \ + MCS_DURATION(_streams, _sgi, _ht40 ? 216 : 104) >> _s, \ + MCS_DURATION(_streams, _sgi, _ht40 ? 324 : 156) >> _s, \ + MCS_DURATION(_streams, _sgi, _ht40 ? 432 : 208) >> _s, \ + MCS_DURATION(_streams, _sgi, _ht40 ? 486 : 234) >> _s, \ + MCS_DURATION(_streams, _sgi, _ht40 ? 540 : 260) >> _s \ } \ } @@ -80,9 +81,10 @@ #define BW2VBPS(_bw, r3, r2, r1) \ (_bw == BW_80 ? r3 : _bw == BW_40 ? r2 : r1) -#define VHT_GROUP(_streams, _sgi, _bw) \ +#define VHT_GROUP(_streams, _sgi, _bw, _s) \ [VHT_GROUP_IDX(_streams, _sgi, _bw)] = { \ .streams = _streams, \ + .shift = _s, \ .flags = \ IEEE80211_TX_RC_VHT_MCS | \ (_sgi ? IEEE80211_TX_RC_SHORT_GI : 0) | \ @@ -90,25 +92,25 @@ _bw == BW_40 ? IEEE80211_TX_RC_40_MHZ_WIDTH : 0), \ .duration = { \ MCS_DURATION(_streams, _sgi, \ - BW2VBPS(_bw, 117, 54, 26)), \ + BW2VBPS(_bw, 117, 54, 26)) >> _s, \ MCS_DURATION(_streams, _sgi, \ - BW2VBPS(_bw, 234, 108, 52)), \ + BW2VBPS(_bw, 234, 108, 52)) >> _s, \ MCS_DURATION(_streams, _sgi, \ - BW2VBPS(_bw, 351, 162, 78)), \ + BW2VBPS(_bw, 351, 162, 78)) >> _s, \ MCS_DURATION(_streams, _sgi, \ - BW2VBPS(_bw, 468, 216, 104)), \ + BW2VBPS(_bw, 468, 216, 104)) >> _s, \ MCS_DURATION(_streams, _sgi, \ - BW2VBPS(_bw, 702, 324, 156)), \ + BW2VBPS(_bw, 702, 324, 156)) >> _s, \ MCS_DURATION(_streams, _sgi, \ - BW2VBPS(_bw, 936, 432, 208)), \ + BW2VBPS(_bw, 936, 432, 208)) >> _s, \ MCS_DURATION(_streams, _sgi, \ - BW2VBPS(_bw, 1053, 486, 234)), \ + BW2VBPS(_bw, 1053, 486, 234)) >> _s, \ MCS_DURATION(_streams, _sgi, \ - BW2VBPS(_bw, 1170, 540, 260)), \ + BW2VBPS(_bw, 1170, 540, 260)) >> _s, \ MCS_DURATION(_streams, _sgi, \ - BW2VBPS(_bw, 1404, 648, 312)), \ + BW2VBPS(_bw, 1404, 648, 312)) >> _s, \ MCS_DURATION(_streams, _sgi, \ - BW2VBPS(_bw, 1560, 720, 346)) \ + BW2VBPS(_bw, 1560, 720, 346)) >> _s \ } \ } @@ -121,19 +123,20 @@ (CCK_DURATION((_bitrate > 10 ? 20 : 10), false, 60) + \ CCK_DURATION(_bitrate, _short, AVG_PKT_SIZE)) -#define CCK_DURATION_LIST(_short) \ - CCK_ACK_DURATION(10, _short), \ - CCK_ACK_DURATION(20, _short), \ - CCK_ACK_DURATION(55, _short), \ - CCK_ACK_DURATION(110, _short) +#define CCK_DURATION_LIST(_short, _s) \ + CCK_ACK_DURATION(10, _short) >> _s, \ + CCK_ACK_DURATION(20, _short) >> _s, \ + CCK_ACK_DURATION(55, _short) >> _s, \ + CCK_ACK_DURATION(110, _short) >> _s -#define CCK_GROUP \ +#define CCK_GROUP(_s) \ [MINSTREL_CCK_GROUP] = { \ .streams = 0, \ .flags = 0, \ + .shift = _s, \ .duration = { \ - CCK_DURATION_LIST(false), \ - CCK_DURATION_LIST(true) \ + CCK_DURATION_LIST(false, _s), \ + CCK_DURATION_LIST(true, _s) \ } \ } @@ -151,47 +154,47 @@ MODULE_PARM_DESC(minstrel_vht_only, * BW -> SGI -> #streams */ const struct mcs_group minstrel_mcs_groups[] = { - MCS_GROUP(1, 0, BW_20), - MCS_GROUP(2, 0, BW_20), - MCS_GROUP(3, 0, BW_20), - - MCS_GROUP(1, 1, BW_20), - MCS_GROUP(2, 1, BW_20), - MCS_GROUP(3, 1, BW_20), - - MCS_GROUP(1, 0, BW_40), - MCS_GROUP(2, 0, BW_40), - MCS_GROUP(3, 0, BW_40), - - MCS_GROUP(1, 1, BW_40), - MCS_GROUP(2, 1, BW_40), - MCS_GROUP(3, 1, BW_40), - - CCK_GROUP, - - VHT_GROUP(1, 0, BW_20), - VHT_GROUP(2, 0, BW_20), - VHT_GROUP(3, 0, BW_20), - - VHT_GROUP(1, 1, BW_20), - VHT_GROUP(2, 1, BW_20), - VHT_GROUP(3, 1, BW_20), - - VHT_GROUP(1, 0, BW_40), - VHT_GROUP(2, 0, BW_40), - VHT_GROUP(3, 0, BW_40), - - VHT_GROUP(1, 1, BW_40), - VHT_GROUP(2, 1, BW_40), - VHT_GROUP(3, 1, BW_40), - - VHT_GROUP(1, 0, BW_80), - VHT_GROUP(2, 0, BW_80), - VHT_GROUP(3, 0, BW_80), - - VHT_GROUP(1, 1, BW_80), - VHT_GROUP(2, 1, BW_80), - VHT_GROUP(3, 1, BW_80), + MCS_GROUP(1, 0, BW_20, 5), + MCS_GROUP(2, 0, BW_20, 4), + MCS_GROUP(3, 0, BW_20, 4), + + MCS_GROUP(1, 1, BW_20, 5), + MCS_GROUP(2, 1, BW_20, 4), + MCS_GROUP(3, 1, BW_20, 4), + + MCS_GROUP(1, 0, BW_40, 4), + MCS_GROUP(2, 0, BW_40, 4), + MCS_GROUP(3, 0, BW_40, 4), + + MCS_GROUP(1, 1, BW_40, 4), + MCS_GROUP(2, 1, BW_40, 4), + MCS_GROUP(3, 1, BW_40, 4), + + CCK_GROUP(8), + + VHT_GROUP(1, 0, BW_20, 5), + VHT_GROUP(2, 0, BW_20, 4), + VHT_GROUP(3, 0, BW_20, 4), + + VHT_GROUP(1, 1, BW_20, 5), + VHT_GROUP(2, 1, BW_20, 4), + VHT_GROUP(3, 1, BW_20, 4), + + VHT_GROUP(1, 0, BW_40, 4), + VHT_GROUP(2, 0, BW_40, 4), + VHT_GROUP(3, 0, BW_40, 4), + + VHT_GROUP(1, 1, BW_40, 4), + VHT_GROUP(2, 1, BW_40, 4), + VHT_GROUP(3, 1, BW_40, 4), + + VHT_GROUP(1, 0, BW_80, 4), + VHT_GROUP(2, 0, BW_80, 4), + VHT_GROUP(3, 0, BW_80, 4), + + VHT_GROUP(1, 1, BW_80, 4), + VHT_GROUP(2, 1, BW_80, 4), + VHT_GROUP(3, 1, BW_80, 4), }; static u8 sample_table[SAMPLE_COLUMNS][MCS_GROUP_RATES] __read_mostly; @@ -307,7 +310,8 @@ minstrel_ht_get_tp_avg(struct minstrel_h if (group != MINSTREL_CCK_GROUP) nsecs = 1000 * mi->overhead / MINSTREL_TRUNC(mi->avg_ampdu_len); - nsecs += minstrel_mcs_groups[group].duration[rate]; + nsecs += minstrel_mcs_groups[group].duration[rate] << + minstrel_mcs_groups[group].shift; /* * For the throughput calculation, limit the probability value to 90% to @@ -755,12 +759,19 @@ minstrel_ht_tx_status(void *priv, struct minstrel_ht_update_rates(mp, mi); } +static inline int +minstrel_get_duration(int index) +{ + const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES]; + unsigned int duration = group->duration[index % MCS_GROUP_RATES]; + return duration << group->shift; +} + static void minstrel_calc_retransmit(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, int index) { struct minstrel_rate_stats *mrs; - const struct mcs_group *group; unsigned int tx_time, tx_time_rtscts, tx_time_data; unsigned int cw = mp->cw_min; unsigned int ctime = 0; @@ -779,8 +790,7 @@ minstrel_calc_retransmit(struct minstrel mrs->retry_count_rtscts = 2; mrs->retry_updated = true; - group = &minstrel_mcs_groups[index / MCS_GROUP_RATES]; - tx_time_data = group->duration[index % MCS_GROUP_RATES] * ampdu_len / 1000; + tx_time_data = minstrel_get_duration(index) * ampdu_len / 1000; /* Contention time for first 2 tries */ ctime = (t_slot * cw) >> 1; @@ -874,20 +884,24 @@ minstrel_ht_get_max_amsdu_len(struct min int group = mi->max_prob_rate / MCS_GROUP_RATES; const struct mcs_group *g = &minstrel_mcs_groups[group]; int rate = mi->max_prob_rate % MCS_GROUP_RATES; + unsigned int duration; /* Disable A-MSDU if max_prob_rate is bad */ if (mi->groups[group].rates[rate].prob_ewma < MINSTREL_FRAC(50, 100)) return 1; + duration = g->duration[rate]; + duration <<= g->shift; + /* If the rate is slower than single-stream MCS1, make A-MSDU limit small */ - if (g->duration[rate] > MCS_DURATION(1, 0, 52)) + if (duration > MCS_DURATION(1, 0, 52)) return 500; /* * If the rate is slower than single-stream MCS4, limit A-MSDU to usual * data packet size */ - if (g->duration[rate] > MCS_DURATION(1, 0, 104)) + if (duration > MCS_DURATION(1, 0, 104)) return 1600; /* @@ -895,7 +909,7 @@ minstrel_ht_get_max_amsdu_len(struct min * rate success probability is less than 75%, limit A-MSDU to twice the usual * data packet size */ - if (g->duration[rate] > MCS_DURATION(1, 0, 260) || + if (duration > MCS_DURATION(1, 0, 260) || (minstrel_ht_get_prob_ewma(mi, mi->max_tp_rate[0]) < MINSTREL_FRAC(75, 100))) return 3200; @@ -942,13 +956,6 @@ minstrel_ht_update_rates(struct minstrel rate_control_set_rates(mp->hw, mi->sta, rates); } -static inline int -minstrel_get_duration(int index) -{ - const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES]; - return group->duration[index % MCS_GROUP_RATES]; -} - static int minstrel_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) { --- a/net/mac80211/rc80211_minstrel_ht.h +++ b/net/mac80211/rc80211_minstrel_ht.h @@ -33,9 +33,10 @@ #define MCS_GROUP_RATES 10 struct mcs_group { - u32 flags; - unsigned int streams; - unsigned int duration[MCS_GROUP_RATES]; + u16 flags; + u8 streams; + u8 shift; + u16 duration[MCS_GROUP_RATES]; }; extern const struct mcs_group minstrel_mcs_groups[]; --- a/net/mac80211/rc80211_minstrel_ht_debugfs.c +++ b/net/mac80211/rc80211_minstrel_ht_debugfs.c @@ -58,6 +58,7 @@ minstrel_ht_stats_dump(struct minstrel_h static const int bitrates[4] = { 10, 20, 55, 110 }; int idx = i * MCS_GROUP_RATES + j; unsigned int prob_ewmsd; + unsigned int duration; if (!(mi->supported[i] & BIT(j))) continue; @@ -95,7 +96,9 @@ minstrel_ht_stats_dump(struct minstrel_h p += sprintf(p, " %3u ", idx); /* tx_time[rate(i)] in usec */ - tx_time = DIV_ROUND_CLOSEST(mg->duration[j], 1000); + duration = mg->duration[j]; + duration <<= mg->shift; + tx_time = DIV_ROUND_CLOSEST(duration, 1000); p += sprintf(p, "%6u ", tx_time); tp_max = minstrel_ht_get_tp_avg(mi, i, j, MINSTREL_FRAC(100, 100)); @@ -204,6 +207,7 @@ minstrel_ht_stats_csv_dump(struct minstr static const int bitrates[4] = { 10, 20, 55, 110 }; int idx = i * MCS_GROUP_RATES + j; unsigned int prob_ewmsd; + unsigned int duration; if (!(mi->supported[i] & BIT(j))) continue; @@ -238,7 +242,10 @@ minstrel_ht_stats_csv_dump(struct minstr } p += sprintf(p, "%u,", idx); - tx_time = DIV_ROUND_CLOSEST(mg->duration[j], 1000); + + duration = mg->duration[j]; + duration <<= mg->shift; + tx_time = DIV_ROUND_CLOSEST(duration, 1000); p += sprintf(p, "%u,", tx_time); tp_max = minstrel_ht_get_tp_avg(mi, i, j, MINSTREL_FRAC(100, 100));