2 * Copyright 2002-2005, Instant802 Networks, Inc.
3 * Copyright 2005, Devicescape Software, Inc.
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
10 #include <linux/init.h>
11 #include <linux/netdevice.h>
12 #include <linux/types.h>
13 #include <linux/slab.h>
14 #include <linux/skbuff.h>
15 #include <linux/compiler.h>
16 #include <linux/module.h>
18 #include <net/mac80211.h>
19 #include "ieee80211_i.h"
20 #include "ieee80211_rate.h"
24 /* This is a minimal implementation of TX rate controlling that can be used
25 * as the default when no improved mechanisms are available. */
27 #define RATE_CONTROL_NUM_DOWN 20
28 #define RATE_CONTROL_NUM_UP 15
30 #define RATE_CONTROL_EMERG_DEC 2
31 #define RATE_CONTROL_INTERVAL (HZ / 20)
32 #define RATE_CONTROL_MIN_TX 10
34 static void rate_control_rate_inc(struct ieee80211_local
*local
,
37 struct ieee80211_sub_if_data
*sdata
;
38 struct ieee80211_hw_mode
*mode
;
42 sdata
= IEEE80211_DEV_TO_SUB_IF(sta
->dev
);
43 if (sdata
->bss
&& sdata
->bss
->force_unicast_rateidx
> -1) {
44 /* forced unicast rate - do not change STA rate */
48 mode
= local
->oper_hw_mode
;
49 maxrate
= sdata
->bss
? sdata
->bss
->max_ratectrl_rateidx
: -1;
51 if (i
> mode
->num_rates
)
52 i
= mode
->num_rates
- 2;
54 while (i
+ 1 < mode
->num_rates
) {
56 if (sta
->supp_rates
& BIT(i
) &&
57 mode
->rates
[i
].flags
& IEEE80211_RATE_SUPPORTED
&&
58 (maxrate
< 0 || i
<= maxrate
)) {
66 static void rate_control_rate_dec(struct ieee80211_local
*local
,
69 struct ieee80211_sub_if_data
*sdata
;
70 struct ieee80211_hw_mode
*mode
;
73 sdata
= IEEE80211_DEV_TO_SUB_IF(sta
->dev
);
74 if (sdata
->bss
&& sdata
->bss
->force_unicast_rateidx
> -1) {
75 /* forced unicast rate - do not change STA rate */
79 mode
= local
->oper_hw_mode
;
80 if (i
> mode
->num_rates
)
85 if (sta
->supp_rates
& BIT(i
) &&
86 mode
->rates
[i
].flags
& IEEE80211_RATE_SUPPORTED
) {
93 struct global_rate_control
{
97 struct sta_rate_control
{
98 unsigned long last_rate_change
;
102 unsigned long avg_rate_update
;
106 #ifdef CONFIG_MAC80211_DEBUGFS
107 struct dentry
*tx_avg_rate_sum_dentry
;
108 struct dentry
*tx_avg_rate_num_dentry
;
113 static void rate_control_simple_tx_status(void *priv
, struct net_device
*dev
,
115 struct ieee80211_tx_status
*status
)
117 struct ieee80211_local
*local
= wdev_priv(dev
->ieee80211_ptr
);
118 struct ieee80211_hdr
*hdr
= (struct ieee80211_hdr
*) skb
->data
;
119 struct sta_info
*sta
;
120 struct sta_rate_control
*srctrl
;
122 sta
= sta_info_get(local
, hdr
->addr1
);
127 srctrl
= sta
->rate_ctrl_priv
;
128 srctrl
->tx_num_xmit
++;
129 if (status
->excessive_retries
) {
130 srctrl
->tx_num_failures
++;
131 sta
->tx_retry_failed
++;
132 sta
->tx_num_consecutive_failures
++;
133 sta
->tx_num_mpdu_fail
++;
135 sta
->last_ack_rssi
[0] = sta
->last_ack_rssi
[1];
136 sta
->last_ack_rssi
[1] = sta
->last_ack_rssi
[2];
137 sta
->last_ack_rssi
[2] = status
->ack_signal
;
138 sta
->tx_num_consecutive_failures
= 0;
139 sta
->tx_num_mpdu_ok
++;
141 sta
->tx_retry_count
+= status
->retry_count
;
142 sta
->tx_num_mpdu_fail
+= status
->retry_count
;
144 if (time_after(jiffies
,
145 srctrl
->last_rate_change
+ RATE_CONTROL_INTERVAL
) &&
146 srctrl
->tx_num_xmit
> RATE_CONTROL_MIN_TX
) {
148 srctrl
->last_rate_change
= jiffies
;
150 per_failed
= (100 * sta
->tx_num_mpdu_fail
) /
151 (sta
->tx_num_mpdu_fail
+ sta
->tx_num_mpdu_ok
);
152 /* TODO: calculate average per_failed to make adjusting
153 * parameters easier */
155 if (net_ratelimit()) {
156 printk(KERN_DEBUG
"MPDU fail=%d ok=%d per_failed=%d\n",
157 sta
->tx_num_mpdu_fail
, sta
->tx_num_mpdu_ok
,
163 * XXX: Make these configurable once we have an
164 * interface to the rate control algorithms
166 if (per_failed
> RATE_CONTROL_NUM_DOWN
) {
167 rate_control_rate_dec(local
, sta
);
168 } else if (per_failed
< RATE_CONTROL_NUM_UP
) {
169 rate_control_rate_inc(local
, sta
);
171 srctrl
->tx_avg_rate_sum
+= status
->control
.rate
->rate
;
172 srctrl
->tx_avg_rate_num
++;
173 srctrl
->tx_num_failures
= 0;
174 srctrl
->tx_num_xmit
= 0;
175 } else if (sta
->tx_num_consecutive_failures
>=
176 RATE_CONTROL_EMERG_DEC
) {
177 rate_control_rate_dec(local
, sta
);
180 if (srctrl
->avg_rate_update
+ 60 * HZ
< jiffies
) {
181 srctrl
->avg_rate_update
= jiffies
;
182 if (srctrl
->tx_avg_rate_num
> 0) {
183 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
184 DECLARE_MAC_BUF(mac
);
185 printk(KERN_DEBUG
"%s: STA %s Average rate: "
187 dev
->name
, print_mac(mac
, sta
->addr
),
188 srctrl
->tx_avg_rate_sum
/
189 srctrl
->tx_avg_rate_num
,
190 srctrl
->tx_avg_rate_sum
,
191 srctrl
->tx_avg_rate_num
);
192 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
193 srctrl
->tx_avg_rate_sum
= 0;
194 srctrl
->tx_avg_rate_num
= 0;
203 rate_control_simple_get_rate(void *priv
, struct net_device
*dev
,
204 struct ieee80211_hw_mode
*mode
,
206 struct rate_selection
*sel
)
208 struct ieee80211_local
*local
= wdev_priv(dev
->ieee80211_ptr
);
209 struct ieee80211_hdr
*hdr
= (struct ieee80211_hdr
*) skb
->data
;
210 struct sta_info
*sta
;
213 sta
= sta_info_get(local
, hdr
->addr1
);
216 sel
->rate
= rate_lowest(local
, mode
, NULL
);
220 rateidx
= sta
->txrate
;
222 if (rateidx
>= mode
->num_rates
)
223 rateidx
= mode
->num_rates
- 1;
227 sel
->rate
= &mode
->rates
[rateidx
];
231 static void rate_control_simple_rate_init(void *priv
, void *priv_sta
,
232 struct ieee80211_local
*local
,
233 struct sta_info
*sta
)
235 struct ieee80211_hw_mode
*mode
;
238 mode
= local
->oper_hw_mode
;
239 /* TODO: This routine should consider using RSSI from previous packets
240 * as we need to have IEEE 802.1X auth succeed immediately after assoc..
241 * Until that method is implemented, we will use the lowest supported rate
242 * as a workaround, */
243 for (i
= 0; i
< mode
->num_rates
; i
++) {
244 if ((sta
->supp_rates
& BIT(i
)) &&
245 (mode
->rates
[i
].flags
& IEEE80211_RATE_SUPPORTED
)) {
253 static void * rate_control_simple_alloc(struct ieee80211_local
*local
)
255 struct global_rate_control
*rctrl
;
257 rctrl
= kzalloc(sizeof(*rctrl
), GFP_ATOMIC
);
263 static void rate_control_simple_free(void *priv
)
265 struct global_rate_control
*rctrl
= priv
;
270 static void rate_control_simple_clear(void *priv
)
275 static void * rate_control_simple_alloc_sta(void *priv
, gfp_t gfp
)
277 struct sta_rate_control
*rctrl
;
279 rctrl
= kzalloc(sizeof(*rctrl
), gfp
);
285 static void rate_control_simple_free_sta(void *priv
, void *priv_sta
)
287 struct sta_rate_control
*rctrl
= priv_sta
;
291 #ifdef CONFIG_MAC80211_DEBUGFS
293 static int open_file_generic(struct inode
*inode
, struct file
*file
)
295 file
->private_data
= inode
->i_private
;
299 static ssize_t
sta_tx_avg_rate_sum_read(struct file
*file
,
300 char __user
*userbuf
,
301 size_t count
, loff_t
*ppos
)
303 struct sta_rate_control
*srctrl
= file
->private_data
;
306 sprintf(buf
, "%d\n", srctrl
->tx_avg_rate_sum
);
307 return simple_read_from_buffer(userbuf
, count
, ppos
, buf
, strlen(buf
));
310 static const struct file_operations sta_tx_avg_rate_sum_ops
= {
311 .read
= sta_tx_avg_rate_sum_read
,
312 .open
= open_file_generic
,
315 static ssize_t
sta_tx_avg_rate_num_read(struct file
*file
,
316 char __user
*userbuf
,
317 size_t count
, loff_t
*ppos
)
319 struct sta_rate_control
*srctrl
= file
->private_data
;
322 sprintf(buf
, "%d\n", srctrl
->tx_avg_rate_num
);
323 return simple_read_from_buffer(userbuf
, count
, ppos
, buf
, strlen(buf
));
326 static const struct file_operations sta_tx_avg_rate_num_ops
= {
327 .read
= sta_tx_avg_rate_num_read
,
328 .open
= open_file_generic
,
331 static void rate_control_simple_add_sta_debugfs(void *priv
, void *priv_sta
,
334 struct sta_rate_control
*srctrl
= priv_sta
;
336 srctrl
->tx_avg_rate_num_dentry
=
337 debugfs_create_file("rc_simple_sta_tx_avg_rate_num", 0400,
338 dir
, srctrl
, &sta_tx_avg_rate_num_ops
);
339 srctrl
->tx_avg_rate_sum_dentry
=
340 debugfs_create_file("rc_simple_sta_tx_avg_rate_sum", 0400,
341 dir
, srctrl
, &sta_tx_avg_rate_sum_ops
);
344 static void rate_control_simple_remove_sta_debugfs(void *priv
, void *priv_sta
)
346 struct sta_rate_control
*srctrl
= priv_sta
;
348 debugfs_remove(srctrl
->tx_avg_rate_sum_dentry
);
349 debugfs_remove(srctrl
->tx_avg_rate_num_dentry
);
353 static struct rate_control_ops mac80211_rcsimple
= {
355 .tx_status
= rate_control_simple_tx_status
,
356 .get_rate
= rate_control_simple_get_rate
,
357 .rate_init
= rate_control_simple_rate_init
,
358 .clear
= rate_control_simple_clear
,
359 .alloc
= rate_control_simple_alloc
,
360 .free
= rate_control_simple_free
,
361 .alloc_sta
= rate_control_simple_alloc_sta
,
362 .free_sta
= rate_control_simple_free_sta
,
363 #ifdef CONFIG_MAC80211_DEBUGFS
364 .add_sta_debugfs
= rate_control_simple_add_sta_debugfs
,
365 .remove_sta_debugfs
= rate_control_simple_remove_sta_debugfs
,
369 MODULE_LICENSE("GPL");
370 MODULE_DESCRIPTION("Simple rate control algorithm");
372 int __init
rc80211_simple_init(void)
374 return ieee80211_rate_control_register(&mac80211_rcsimple
);
377 void __exit
rc80211_simple_exit(void)
379 ieee80211_rate_control_unregister(&mac80211_rcsimple
);
382 #ifdef CONFIG_MAC80211_RC_SIMPLE_MODULE
383 module_init(rc80211_simple_init
);
384 module_exit(rc80211_simple_exit
);