X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=net%2Fmac80211%2Frc80211_pid_algo.c;h=3b77410588e734258706245c8057d741a7916e8d;hb=d55a4528f7f607ca2872fec18574bc8cec060f05;hp=3e26280d3142044f5d7e37d08caff4a2999a83db;hpb=fa44327c06492c9bd625dbc8dbe35e5d5965fec6;p=linux-2.6 diff --git a/net/mac80211/rc80211_pid_algo.c b/net/mac80211/rc80211_pid_algo.c index 3e26280d31..3b77410588 100644 --- a/net/mac80211/rc80211_pid_algo.c +++ b/net/mac80211/rc80211_pid_algo.c @@ -2,7 +2,7 @@ * Copyright 2002-2005, Instant802 Networks, Inc. * Copyright 2005, Devicescape Software, Inc. * Copyright 2007, Mattias Nissler - * Copyright 2007, Stefano Brivio + * Copyright 2007-2008, Stefano Brivio * * 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 @@ -12,7 +12,7 @@ #include #include #include - +#include #include #include "ieee80211_rate.h" @@ -63,76 +63,66 @@ * RC_PID_ARITH_SHIFT. */ - -/* Shift the adjustment so that we won't switch to a lower rate if it exhibited - * a worse failed frames behaviour and we'll choose the highest rate whose - * failed frames behaviour is not worse than the one of the original rate - * target. While at it, check that the adjustment is within the ranges. Then, - * provide the new rate index. */ -static int rate_control_pid_shift_adjust(struct rc_pid_rateinfo *r, - int adj, int cur, int l) -{ - int i, j, k, tmp; - - j = r[cur].rev_index; - i = j + adj; - - if (i < 0) - return r[0].index; - if (i >= l - 1) - return r[l - 1].index; - - tmp = i; - - if (adj < 0) { - for (k = j; k >= i; k--) - if (r[k].diff <= r[j].diff) - tmp = k; - } else { - for (k = i + 1; k + i < l; k++) - if (r[k].diff <= r[i].diff) - tmp = k; - } - - return r[tmp].index; -} - +/* Adjust the rate while ensuring that we won't switch to a lower rate if it + * exhibited a worse failed frames behaviour and we'll choose the highest rate + * whose failed frames behaviour is not worse than the one of the original rate + * target. While at it, check that the new rate is valid. */ static void rate_control_pid_adjust_rate(struct ieee80211_local *local, struct sta_info *sta, int adj, struct rc_pid_rateinfo *rinfo) { struct ieee80211_sub_if_data *sdata; struct ieee80211_hw_mode *mode; - int newidx; - int maxrate; - int back = (adj > 0) ? 1 : -1; + int cur_sorted, new_sorted, probe, tmp, n_bitrates; + int cur = 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; - } mode = local->oper_hw_mode; - maxrate = sdata->bss ? sdata->bss->max_ratectrl_rateidx : -1; + n_bitrates = mode->num_rates; - newidx = rate_control_pid_shift_adjust(rinfo, adj, sta->txrate, - mode->num_rates); + /* Map passed arguments to sorted values. */ + cur_sorted = rinfo[cur].rev_index; + new_sorted = cur_sorted + adj; - while (newidx != sta->txrate) { - if (rate_supported(sta, mode, newidx) && - (maxrate < 0 || newidx <= maxrate)) { - sta->txrate = newidx; - break; - } + /* Check limits. */ + if (new_sorted < 0) + new_sorted = rinfo[0].rev_index; + else if (new_sorted >= n_bitrates) + new_sorted = rinfo[n_bitrates - 1].rev_index; - newidx += back; + tmp = new_sorted; + + if (adj < 0) { + /* Ensure that the rate decrease isn't disadvantageous. */ + for (probe = cur_sorted; probe >= new_sorted; probe--) + if (rinfo[probe].diff <= rinfo[cur_sorted].diff && + rate_supported(sta, mode, rinfo[probe].index)) + tmp = probe; + } else { + /* Look for rate increase with zero (or below) cost. */ + for (probe = new_sorted + 1; probe < n_bitrates; probe++) + if (rinfo[probe].diff <= rinfo[new_sorted].diff && + rate_supported(sta, mode, rinfo[probe].index)) + tmp = probe; } + /* Fit the rate found to the nearest supported rate. */ + do { + if (rate_supported(sta, mode, rinfo[tmp].index)) { + sta->txrate = rinfo[tmp].index; + break; + } + if (adj < 0) + tmp--; + else + tmp++; + } while (tmp < n_bitrates && tmp >= 0); + #ifdef CONFIG_MAC80211_DEBUGFS rate_control_pid_event_rate_change( &((struct rc_pid_sta_info *)sta->rate_ctrl_priv)->events, - newidx, mode->rates[newidx].rate); + cur, mode->rates[cur].rate); #endif } @@ -241,6 +231,7 @@ static void rate_control_pid_tx_status(void *priv, struct net_device *dev, { struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; + struct ieee80211_sub_if_data *sdata; struct rc_pid_info *pinfo = priv; struct sta_info *sta; struct rc_pid_sta_info *spinfo; @@ -251,10 +242,17 @@ static void rate_control_pid_tx_status(void *priv, struct net_device *dev, if (!sta) return; + /* Don't update the state if we're not controlling the rate. */ + sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev); + if (sdata->bss && sdata->bss->force_unicast_rateidx > -1) { + sta->txrate = sdata->bss->max_ratectrl_rateidx; + return; + } + /* Ignore all frames that were sent with a different rate than the rate * we currently advise mac80211 to use. */ if (status->control.rate != &local->oper_hw_mode->rates[sta->txrate]) - return; + goto ignore; spinfo = sta->rate_ctrl_priv; spinfo->tx_num_xmit++; @@ -295,6 +293,7 @@ static void rate_control_pid_tx_status(void *priv, struct net_device *dev, if (time_after(jiffies, spinfo->last_sample + period)) rate_control_pid_sample(pinfo, local, sta); +ignore: sta_info_put(sta); } @@ -305,22 +304,36 @@ static void rate_control_pid_get_rate(void *priv, struct net_device *dev, { struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; + struct ieee80211_sub_if_data *sdata; struct sta_info *sta; int rateidx; + u16 fc; sta = sta_info_get(local, hdr->addr1); - if (!sta) { - sel->rate = rate_lowest(local, mode, NULL); - sta_info_put(sta); + /* Send management frames and broadcast/multicast data using lowest + * rate. */ + fc = le16_to_cpu(hdr->frame_control); + if ((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA || + is_multicast_ether_addr(hdr->addr1) || !sta) { + sel->rate = rate_lowest(local, mode, sta); + if (sta) + sta_info_put(sta); return; } + /* If a forced rate is in effect, select it. */ + 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 >= mode->num_rates) rateidx = mode->num_rates - 1; + sta->last_txrate = rateidx; + sta_info_put(sta); sel->rate = &mode->rates[rateidx]; @@ -477,6 +490,8 @@ static void *rate_control_pid_alloc_sta(void *priv, gfp_t gfp) if (spinfo == NULL) return NULL; + spinfo->last_sample = jiffies; + #ifdef CONFIG_MAC80211_DEBUGFS spin_lock_init(&spinfo->events.lock); init_waitqueue_head(&spinfo->events.waitqueue); @@ -491,7 +506,7 @@ static void rate_control_pid_free_sta(void *priv, void *priv_sta) kfree(spinfo); } -struct rate_control_ops mac80211_rcpid = { +static struct rate_control_ops mac80211_rcpid = { .name = "pid", .tx_status = rate_control_pid_tx_status, .get_rate = rate_control_pid_get_rate, @@ -506,3 +521,23 @@ struct rate_control_ops mac80211_rcpid = { .remove_sta_debugfs = rate_control_pid_remove_sta_debugfs, #endif }; + +MODULE_DESCRIPTION("PID controller based rate control algorithm"); +MODULE_AUTHOR("Stefano Brivio"); +MODULE_AUTHOR("Mattias Nissler"); +MODULE_LICENSE("GPL"); + +int __init rc80211_pid_init(void) +{ + return ieee80211_rate_control_register(&mac80211_rcpid); +} + +void rc80211_pid_exit(void) +{ + ieee80211_rate_control_unregister(&mac80211_rcpid); +} + +#ifdef CONFIG_MAC80211_RC_PID_MODULE +module_init(rc80211_pid_init); +module_exit(rc80211_pid_exit); +#endif