diff options
Diffstat (limited to 'target/linux/package/ieee80211-dscape/src/rate_control.c')
-rw-r--r-- | target/linux/package/ieee80211-dscape/src/rate_control.c | 381 |
1 files changed, 381 insertions, 0 deletions
diff --git a/target/linux/package/ieee80211-dscape/src/rate_control.c b/target/linux/package/ieee80211-dscape/src/rate_control.c new file mode 100644 index 0000000000..8782a756da --- /dev/null +++ b/target/linux/package/ieee80211-dscape/src/rate_control.c @@ -0,0 +1,381 @@ +/* + * Copyright 2002-2005, Instant802 Networks, Inc. + * Copyright 2005, Devicescape Software, Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/config.h> +#include <linux/version.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/netdevice.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/skbuff.h> +#include <linux/compiler.h> + +#include <net/ieee80211.h> +#include "ieee80211_i.h" +#include "rate_control.h" + + +/* This is a minimal implementation of TX rate controlling that can be used + * as the default when no improved mechanisms are available. */ + + +#define RATE_CONTROL_EMERG_DEC 2 +#define RATE_CONTROL_INTERVAL (HZ / 20) +#define RATE_CONTROL_MIN_TX 10 + + +static void rate_control_rate_inc(struct ieee80211_local *local, + struct sta_info *sta) +{ + struct ieee80211_sub_if_data *sdata; + int i = sta->txrate; + int maxrate; + + sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev); + if (sdata->bss && sdata->bss->force_unicast_rateidx > -1) { + /* forced unicast rate - do not change STA rate */ + return; + } + + maxrate = sdata->bss ? sdata->bss->max_ratectrl_rateidx : -1; + + if (i > local->num_curr_rates) + i = local->num_curr_rates - 2; + + while (i + 1 < local->num_curr_rates) { + i++; + if (sta->supp_rates & BIT(i) && + local->curr_rates[i].flags & IEEE80211_RATE_SUPPORTED && + (maxrate < 0 || i <= maxrate)) { + sta->txrate = i; + break; + } + } +} + + +static void rate_control_rate_dec(struct ieee80211_local *local, + struct sta_info *sta) +{ + struct ieee80211_sub_if_data *sdata; + int i = sta->txrate; + + sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev); + if (sdata->bss && sdata->bss->force_unicast_rateidx > -1) { + /* forced unicast rate - do not change STA rate */ + return; + } + + if (i > local->num_curr_rates) + i = local->num_curr_rates; + + while (i > 0) { + i--; + if (sta->supp_rates & BIT(i) && + local->curr_rates[i].flags & IEEE80211_RATE_SUPPORTED) { + sta->txrate = i; + break; + } + } +} + + +static struct ieee80211_rate * +rate_control_lowest_rate(struct ieee80211_local *local) +{ + int i; + + for (i = 0; i < local->num_curr_rates; i++) { + struct ieee80211_rate *rate = &local->curr_rates[i]; + + if (rate->flags & IEEE80211_RATE_SUPPORTED + ) + return rate; + } + + printk(KERN_DEBUG "rate_control_lowest_rate - no supported rates " + "found\n"); + return &local->curr_rates[0]; +} + + +struct global_rate_control { + int dummy; +}; + +struct sta_rate_control { + unsigned long last_rate_change; + u32 tx_num_failures; + u32 tx_num_xmit; + + unsigned long avg_rate_update; + u32 tx_avg_rate_sum; + u32 tx_avg_rate_num; +}; + + +static void rate_control_simple_tx_status(struct net_device *dev, + struct sk_buff *skb, + struct ieee80211_tx_status *status) +{ + struct ieee80211_local *local = dev->priv; + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; + struct sta_info *sta; + struct sta_rate_control *srctrl; + + sta = sta_info_get(local, hdr->addr1); + + if (!sta) + return; + + srctrl = sta->rate_ctrl_priv; + srctrl->tx_num_xmit++; + if (status->excessive_retries) { + sta->antenna_sel = sta->antenna_sel == 1 ? 2 : 1; + if (local->sta_antenna_sel == STA_ANTENNA_SEL_SW_CTRL_DEBUG) { + printk(KERN_DEBUG "%s: " MACSTR " TX antenna --> %d " + "(@%lu)\n", + dev->name, MAC2STR(hdr->addr1), + sta->antenna_sel, jiffies); + } + srctrl->tx_num_failures++; + sta->tx_retry_failed++; + sta->tx_num_consecutive_failures++; + sta->tx_num_mpdu_fail++; + } else { + sta->last_ack_rssi[0] = sta->last_ack_rssi[1]; + sta->last_ack_rssi[1] = sta->last_ack_rssi[2]; + sta->last_ack_rssi[2] = status->ack_signal; + sta->tx_num_consecutive_failures = 0; + sta->tx_num_mpdu_ok++; + } + sta->tx_retry_count += status->retry_count; + sta->tx_num_mpdu_fail += status->retry_count; + + if (time_after(jiffies, + srctrl->last_rate_change + RATE_CONTROL_INTERVAL) && + srctrl->tx_num_xmit > RATE_CONTROL_MIN_TX) { + u32 per_failed; + srctrl->last_rate_change = jiffies; + + per_failed = (100 * sta->tx_num_mpdu_fail) / + (sta->tx_num_mpdu_fail + sta->tx_num_mpdu_ok); + /* TODO: calculate average per_failed to make adjusting + * parameters easier */ +#if 0 + if (net_ratelimit()) { + printk(KERN_DEBUG "MPDU fail=%d ok=%d per_failed=%d\n", + sta->tx_num_mpdu_fail, sta->tx_num_mpdu_ok, + per_failed); + } +#endif + + if (per_failed > local->rate_ctrl_num_down) { + rate_control_rate_dec(local, sta); + } else if (per_failed < local->rate_ctrl_num_up) { + rate_control_rate_inc(local, sta); + } + srctrl->tx_avg_rate_sum += local->curr_rates[sta->txrate].rate; + srctrl->tx_avg_rate_num++; + srctrl->tx_num_failures = 0; + srctrl->tx_num_xmit = 0; + } else if (sta->tx_num_consecutive_failures >= + RATE_CONTROL_EMERG_DEC) { + rate_control_rate_dec(local, sta); + } + + if (srctrl->avg_rate_update + 60 * HZ < jiffies) { + srctrl->avg_rate_update = jiffies; + if (srctrl->tx_avg_rate_num > 0) { +#ifdef CONFIG_IEEE80211_VERBOSE_DEBUG + printk(KERN_DEBUG "%s: STA " MACSTR " Average rate: " + "%d (%d/%d)\n", + dev->name, MAC2STR(sta->addr), + srctrl->tx_avg_rate_sum / + srctrl->tx_avg_rate_num, + srctrl->tx_avg_rate_sum, + srctrl->tx_avg_rate_num); +#endif /* CONFIG_IEEE80211_VERBOSE_DEBUG */ + srctrl->tx_avg_rate_sum = 0; + srctrl->tx_avg_rate_num = 0; + } + } + + sta_info_release(local, sta); +} + + +static struct ieee80211_rate * +rate_control_simple_get_rate(struct net_device *dev, struct sk_buff *skb, + struct rate_control_extra *extra) +{ + struct ieee80211_local *local = dev->priv; + struct ieee80211_sub_if_data *sdata; + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; + struct sta_info *sta; + int rateidx, nonerp_idx; + u16 fc; + + memset(extra, 0, sizeof(*extra)); + + fc = le16_to_cpu(hdr->frame_control); + if (WLAN_FC_GET_TYPE(fc) != WLAN_FC_TYPE_DATA || + (hdr->addr1[0] & 0x01)) { + /* Send management frames and broadcast/multicast data using + * lowest rate. */ + /* TODO: this could probably be improved.. */ + return rate_control_lowest_rate(local); + } + + sta = sta_info_get(local, hdr->addr1); + + if (!sta) + return rate_control_lowest_rate(local); + + sdata = IEEE80211_DEV_TO_SUB_IF(dev); + if (sdata->bss && sdata->bss->force_unicast_rateidx > -1) + sta->txrate = sdata->bss->force_unicast_rateidx; + + rateidx = sta->txrate; + + if (rateidx >= local->num_curr_rates) + rateidx = local->num_curr_rates - 1; + + sta->last_txrate = rateidx; + nonerp_idx = rateidx; + while (nonerp_idx > 0 && + ((local->curr_rates[nonerp_idx].flags & IEEE80211_RATE_ERP) || + !(local->curr_rates[nonerp_idx].flags & + IEEE80211_RATE_SUPPORTED) || + !(sta->supp_rates & BIT(nonerp_idx)))) + nonerp_idx--; + extra->nonerp_idx = nonerp_idx; + extra->nonerp = &local->curr_rates[extra->nonerp_idx]; + + sta_info_release(local, sta); + + return &local->curr_rates[rateidx]; +} + + +static void rate_control_simple_rate_init(struct ieee80211_local *local, + struct sta_info *sta) +{ + int i; + sta->txrate = 0; + /* TODO: what is a good starting rate for STA? About middle? Maybe not + * the lowest or the highest rate.. Could consider using RSSI from + * previous packets? Need to have IEEE 802.1X auth succeed immediately + * after assoc.. */ + for (i = 0; i < local->num_curr_rates; i++) { + if ((sta->supp_rates & BIT(i)) && + (local->curr_rates[i].flags & IEEE80211_RATE_SUPPORTED)) + sta->txrate = i; + } +} + + +static void * rate_control_simple_alloc(struct ieee80211_local *local) +{ + struct global_rate_control *rctrl; + + rctrl = kmalloc(sizeof(*rctrl), GFP_ATOMIC); + if (rctrl == NULL) { + return NULL; + } + memset(rctrl, 0, sizeof(*rctrl)); + return rctrl; +} + + +static void rate_control_simple_free(void *priv) +{ + struct global_rate_control *rctrl = priv; + kfree(rctrl); +} + + +static void rate_control_simple_clear(void *priv) +{ +} + + +static void * rate_control_simple_alloc_sta(void) +{ + struct sta_rate_control *rctrl; + + rctrl = kmalloc(sizeof(*rctrl), GFP_ATOMIC); + if (rctrl == NULL) { + return NULL; + } + memset(rctrl, 0, sizeof(*rctrl)); + return rctrl; +} + + +static void rate_control_simple_free_sta(void *priv) +{ + struct sta_rate_control *rctrl = priv; + kfree(rctrl); +} + + +static int rate_control_simple_status_sta(struct ieee80211_local *local, + struct sta_info *sta, char *buf) +{ + char *p = buf; + struct sta_rate_control *srctrl = sta->rate_ctrl_priv; + + p += sprintf(p, "tx_avg_rate_sum=%d\n", srctrl->tx_avg_rate_sum); + p += sprintf(p, "tx_avg_rate_num=%d\n", srctrl->tx_avg_rate_num); + if (srctrl->tx_avg_rate_num) + p += sprintf(p, "tx_avg_rate_avg=%d\n", + srctrl->tx_avg_rate_sum / + srctrl->tx_avg_rate_num); + return p - buf; +} + + +static int rate_control_simple_status_global(struct ieee80211_local *local, + char *buf) +{ + return 0; +} + + +static struct rate_control_ops rate_control_simple = { + .name = "simple", + .tx_status = rate_control_simple_tx_status, + .get_rate = rate_control_simple_get_rate, + .rate_init = rate_control_simple_rate_init, + .clear = rate_control_simple_clear, + .status_sta = rate_control_simple_status_sta, + .status_global = rate_control_simple_status_global, + .alloc = rate_control_simple_alloc, + .free = rate_control_simple_free, + .alloc_sta = rate_control_simple_alloc_sta, + .free_sta = rate_control_simple_free_sta, +}; + + +int __init rate_control_simple_init(void) +{ + return ieee80211_rate_control_register(&rate_control_simple); +} + + +static void __exit rate_control_simple_exit(void) +{ + ieee80211_rate_control_unregister(&rate_control_simple); +} + + +module_init(rate_control_simple_init); +module_exit(rate_control_simple_exit); |