q3k/linux
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity
linux/drivers/net/wireless/iwlwifi/iwl-3945-rs.c
Johannes Berg 4b7679a561 mac80211: clean up rate control API 
Long awaited, hard work. This patch totally cleans up the rate control
API to remove the requirement to include internal headers outside of
net/mac80211/.

There's one internal use in the PID algorithm left for mesh networking,
we'll have to figure out a way to clean that one up and decide how to
do the peer link evaluation, possibly independent of the rate control
algorithm or via new API.

Additionally, ath9k is left using the cross-inclusion hack for now, we
will add new API where necessary to make this work properly, but right
now I'm not expert enough to do it. It's still off better than before.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-09-24 16:18:03 -04:00

886 lines
22 KiB
C
Raw Blame History

/******************************************************************************
*
* Copyright(c) 2005 - 2008 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
*
* The full GNU General Public License is included in this distribution in the
* file called LICENSE.
*
* Contact Information:
* James P. Ketrenos <ipw2100-admin@linux.intel.com>
* Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
*
*****************************************************************************/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/skbuff.h>
#include <linux/wireless.h>
#include <net/mac80211.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/delay.h>
#include <linux/workqueue.h>
#include "iwl-3945.h"
#define RS_NAME "iwl-3945-rs"
struct iwl3945_rate_scale_data {
u64 data;
s32 success_counter;
s32 success_ratio;
s32 counter;
s32 average_tpt;
unsigned long stamp;
};
struct iwl3945_rs_sta {
spinlock_t lock;
s32 *expected_tpt;
unsigned long last_partial_flush;
unsigned long last_flush;
u32 flush_time;
u32 last_tx_packets;
u32 tx_packets;
u8 tgg;
u8 flush_pending;
u8 start_rate;
u8 ibss_sta_added;
struct timer_list rate_scale_flush;
struct iwl3945_rate_scale_data win[IWL_RATE_COUNT];
/* used to be in sta_info */
int last_txrate_idx;
};
static s32 iwl3945_expected_tpt_g[IWL_RATE_COUNT] = {
7, 13, 35, 58, 0, 0, 76, 104, 130, 168, 191, 202
};
static s32 iwl3945_expected_tpt_g_prot[IWL_RATE_COUNT] = {
7, 13, 35, 58, 0, 0, 0, 80, 93, 113, 123, 125
};
static s32 iwl3945_expected_tpt_a[IWL_RATE_COUNT] = {
0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186
};
static s32 iwl3945_expected_tpt_b[IWL_RATE_COUNT] = {
7, 13, 35, 58, 0, 0, 0, 0, 0, 0, 0, 0
};
struct iwl3945_tpt_entry {
s8 min_rssi;
u8 index;
};
static struct iwl3945_tpt_entry iwl3945_tpt_table_a[] = {
{-60, IWL_RATE_54M_INDEX},
{-64, IWL_RATE_48M_INDEX},
{-72, IWL_RATE_36M_INDEX},
{-80, IWL_RATE_24M_INDEX},
{-84, IWL_RATE_18M_INDEX},
{-85, IWL_RATE_12M_INDEX},
{-87, IWL_RATE_9M_INDEX},
{-89, IWL_RATE_6M_INDEX}
};
static struct iwl3945_tpt_entry iwl3945_tpt_table_g[] = {
{-60, IWL_RATE_54M_INDEX},
{-64, IWL_RATE_48M_INDEX},
{-68, IWL_RATE_36M_INDEX},
{-80, IWL_RATE_24M_INDEX},
{-84, IWL_RATE_18M_INDEX},
{-85, IWL_RATE_12M_INDEX},
{-86, IWL_RATE_11M_INDEX},
{-88, IWL_RATE_5M_INDEX},
{-90, IWL_RATE_2M_INDEX},
{-92, IWL_RATE_1M_INDEX}
};
#define IWL_RATE_MAX_WINDOW 62
#define IWL_RATE_FLUSH (3*HZ/10)
#define IWL_RATE_WIN_FLUSH (HZ/2)
#define IWL_RATE_HIGH_TH 11520
#define IWL_RATE_MIN_FAILURE_TH 8
#define IWL_RATE_MIN_SUCCESS_TH 8
#define IWL_RATE_DECREASE_TH 1920
static u8 iwl3945_get_rate_index_by_rssi(s32 rssi, enum ieee80211_band band)
{
u32 index = 0;
u32 table_size = 0;
struct iwl3945_tpt_entry *tpt_table = NULL;
if ((rssi < IWL_MIN_RSSI_VAL) || (rssi > IWL_MAX_RSSI_VAL))
rssi = IWL_MIN_RSSI_VAL;
switch (band) {
case IEEE80211_BAND_2GHZ:
tpt_table = iwl3945_tpt_table_g;
table_size = ARRAY_SIZE(iwl3945_tpt_table_g);
break;
case IEEE80211_BAND_5GHZ:
tpt_table = iwl3945_tpt_table_a;
table_size = ARRAY_SIZE(iwl3945_tpt_table_a);
break;
default:
BUG();
break;
}
while ((index < table_size) && (rssi < tpt_table[index].min_rssi))
index++;
index = min(index, (table_size - 1));
return tpt_table[index].index;
}
static void iwl3945_clear_window(struct iwl3945_rate_scale_data *window)
{
window->data = 0;
window->success_counter = 0;
window->success_ratio = -1;
window->counter = 0;
window->average_tpt = IWL_INV_TPT;
window->stamp = 0;
}
/**
* iwl3945_rate_scale_flush_windows - flush out the rate scale windows
*
* Returns the number of windows that have gathered data but were
* not flushed. If there were any that were not flushed, then
* reschedule the rate flushing routine.
*/
static int iwl3945_rate_scale_flush_windows(struct iwl3945_rs_sta *rs_sta)
{
int unflushed = 0;
int i;
unsigned long flags;
/*
* For each rate, if we have collected data on that rate
* and it has been more than IWL_RATE_WIN_FLUSH
* since we flushed, clear out the gathered statistics
*/
for (i = 0; i < IWL_RATE_COUNT; i++) {
if (!rs_sta->win[i].counter)
continue;
spin_lock_irqsave(&rs_sta->lock, flags);
if (time_after(jiffies, rs_sta->win[i].stamp +
IWL_RATE_WIN_FLUSH)) {
IWL_DEBUG_RATE("flushing %d samples of rate "
"index %d\n",
rs_sta->win[i].counter, i);
iwl3945_clear_window(&rs_sta->win[i]);
} else
unflushed++;
spin_unlock_irqrestore(&rs_sta->lock, flags);
}
return unflushed;
}
#define IWL_RATE_FLUSH_MAX 5000 /* msec */
#define IWL_RATE_FLUSH_MIN 50 /* msec */
static void iwl3945_bg_rate_scale_flush(unsigned long data)
{
struct iwl3945_rs_sta *rs_sta = (void *)data;
int unflushed = 0;
unsigned long flags;
u32 packet_count, duration, pps;
IWL_DEBUG_RATE("enter\n");
unflushed = iwl3945_rate_scale_flush_windows(rs_sta);
spin_lock_irqsave(&rs_sta->lock, flags);
rs_sta->flush_pending = 0;
/* Number of packets Rx'd since last time this timer ran */
packet_count = (rs_sta->tx_packets - rs_sta->last_tx_packets) + 1;
rs_sta->last_tx_packets = rs_sta->tx_packets + 1;
if (unflushed) {
duration =
jiffies_to_msecs(jiffies - rs_sta->last_partial_flush);
/* duration = jiffies_to_msecs(rs_sta->flush_time); */
IWL_DEBUG_RATE("Tx'd %d packets in %dms\n",
packet_count, duration);
/* Determine packets per second */
if (duration)
pps = (packet_count * 1000) / duration;
else
pps = 0;
if (pps) {
duration = IWL_RATE_FLUSH_MAX / pps;
if (duration < IWL_RATE_FLUSH_MIN)
duration = IWL_RATE_FLUSH_MIN;
} else
duration = IWL_RATE_FLUSH_MAX;
rs_sta->flush_time = msecs_to_jiffies(duration);
IWL_DEBUG_RATE("new flush period: %d msec ave %d\n",
duration, packet_count);
mod_timer(&rs_sta->rate_scale_flush, jiffies +
rs_sta->flush_time);
rs_sta->last_partial_flush = jiffies;
}
/* If there weren't any unflushed entries, we don't schedule the timer
* to run again */
rs_sta->last_flush = jiffies;
spin_unlock_irqrestore(&rs_sta->lock, flags);
IWL_DEBUG_RATE("leave\n");
}
/**
* iwl3945_collect_tx_data - Update the success/failure sliding window
*
* We keep a sliding window of the last 64 packets transmitted
* at this rate. window->data contains the bitmask of successful
* packets.
*/
static void iwl3945_collect_tx_data(struct iwl3945_rs_sta *rs_sta,
struct iwl3945_rate_scale_data *window,
int success, int retries)
{
unsigned long flags;
if (!retries) {
IWL_DEBUG_RATE("leave: retries == 0 -- should be at least 1\n");
return;
}
while (retries--) {
spin_lock_irqsave(&rs_sta->lock, flags);
/* If we have filled up the window then subtract one from the
* success counter if the high-bit is counting toward
* success */
if (window->counter == IWL_RATE_MAX_WINDOW) {
if (window->data & (1ULL << (IWL_RATE_MAX_WINDOW - 1)))
window->success_counter--;
} else
window->counter++;
/* Slide the window to the left one bit */
window->data = (window->data << 1);
/* If this packet was a success then set the low bit high */
if (success) {
window->success_counter++;
window->data |= 1;
}
/* window->counter can't be 0 -- it is either >0 or
* IWL_RATE_MAX_WINDOW */
window->success_ratio = 12800 * window->success_counter /
window->counter;
/* Tag this window as having been updated */
window->stamp = jiffies;
spin_unlock_irqrestore(&rs_sta->lock, flags);
}
}
static void rs_rate_init(void *priv, struct ieee80211_supported_band *sband,
struct ieee80211_sta *sta, void *priv_sta)
{
struct iwl3945_rs_sta *rs_sta = priv_sta;
int i;
IWL_DEBUG_RATE("enter\n");
/* 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 = IWL_RATE_COUNT - 1; i >= 0; i--) {
if (sta->supp_rates[sband->band] & (1 << i)) {
rs_sta->last_txrate_idx = i;
break;
}
}
/* For 5 GHz band it start at IWL_FIRST_OFDM_RATE */
if (sband->band == IEEE80211_BAND_5GHZ)
rs_sta->last_txrate_idx += IWL_FIRST_OFDM_RATE;
IWL_DEBUG_RATE("leave\n");
}
static void *rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
{
return hw->priv;
}
/* rate scale requires free function to be implemented */
static void rs_free(void *priv)
{
return;
}
static void rs_clear(void *priv)
{
return;
}
static void *rs_alloc_sta(void *priv, struct ieee80211_sta *sta, gfp_t gfp)
{
struct iwl3945_rs_sta *rs_sta;
struct iwl3945_sta_priv *psta = (void *) sta->drv_priv;
int i;
/*
* XXX: If it's using sta->drv_priv anyway, it might
* as well just put all the information there.
*/
IWL_DEBUG_RATE("enter\n");
rs_sta = kzalloc(sizeof(struct iwl3945_rs_sta), gfp);
if (!rs_sta) {
IWL_DEBUG_RATE("leave: ENOMEM\n");
return NULL;
}
psta->rs_sta = rs_sta;
spin_lock_init(&rs_sta->lock);
rs_sta->start_rate = IWL_RATE_INVALID;
/* default to just 802.11b */
rs_sta->expected_tpt = iwl3945_expected_tpt_b;
rs_sta->last_partial_flush = jiffies;
rs_sta->last_flush = jiffies;
rs_sta->flush_time = IWL_RATE_FLUSH;
rs_sta->last_tx_packets = 0;
rs_sta->ibss_sta_added = 0;
init_timer(&rs_sta->rate_scale_flush);
rs_sta->rate_scale_flush.data = (unsigned long)rs_sta;
rs_sta->rate_scale_flush.function = &iwl3945_bg_rate_scale_flush;
for (i = 0; i < IWL_RATE_COUNT; i++)
iwl3945_clear_window(&rs_sta->win[i]);
IWL_DEBUG_RATE("leave\n");
return rs_sta;
}
static void rs_free_sta(void *priv, struct ieee80211_sta *sta,
void *priv_sta)
{
struct iwl3945_sta_priv *psta = (void *) sta->drv_priv;
struct iwl3945_rs_sta *rs_sta = priv_sta;
psta->rs_sta = NULL;
IWL_DEBUG_RATE("enter\n");
del_timer_sync(&rs_sta->rate_scale_flush);
kfree(rs_sta);
IWL_DEBUG_RATE("leave\n");
}
/*
* get ieee prev rate from rate scale table.
* for A and B mode we need to overright prev
* value
*/
static int rs_adjust_next_rate(struct iwl3945_priv *priv, int rate)
{
int next_rate = iwl3945_get_prev_ieee_rate(rate);
switch (priv->band) {
case IEEE80211_BAND_5GHZ:
if (rate == IWL_RATE_12M_INDEX)
next_rate = IWL_RATE_9M_INDEX;
else if (rate == IWL_RATE_6M_INDEX)
next_rate = IWL_RATE_6M_INDEX;
break;
/* XXX cannot be invoked in current mac80211 so not a regression
case MODE_IEEE80211B:
if (rate == IWL_RATE_11M_INDEX_TABLE)
next_rate = IWL_RATE_5M_INDEX_TABLE;
break;
*/
default:
break;
}
return next_rate;
}
/**
* rs_tx_status - Update rate control values based on Tx results
*
* NOTE: Uses iwl3945_priv->retry_rate for the # of retries attempted by
* the hardware for each rate.
*/
static void rs_tx_status(void *priv_rate, struct ieee80211_supported_band *sband,
struct ieee80211_sta *sta, void *priv_sta,
struct sk_buff *skb)
{
u8 retries, current_count;
int scale_rate_index, first_index, last_index;
unsigned long flags;
struct iwl3945_priv *priv = (struct iwl3945_priv *)priv_rate;
struct iwl3945_rs_sta *rs_sta = priv_sta;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
IWL_DEBUG_RATE("enter\n");
retries = info->status.retry_count;
first_index = sband->bitrates[info->tx_rate_idx].hw_value;
if ((first_index < 0) || (first_index >= IWL_RATE_COUNT)) {
IWL_DEBUG_RATE("leave: Rate out of bounds: %d\n", first_index);
return;
}
if (!priv_sta) {
IWL_DEBUG_RATE("leave: No STA priv data to update!\n");
return;
}
rs_sta->tx_packets++;
scale_rate_index = first_index;
last_index = first_index;
/*
* Update the window for each rate. We determine which rates
* were Tx'd based on the total number of retries vs. the number
* of retries configured for each rate -- currently set to the
* priv value 'retry_rate' vs. rate specific
*
* On exit from this while loop last_index indicates the rate
* at which the frame was finally transmitted (or failed if no
* ACK)
*/
while (retries > 0) {
if (retries < priv->retry_rate) {
current_count = retries;
last_index = scale_rate_index;
} else {
current_count = priv->retry_rate;
last_index = rs_adjust_next_rate(priv,
scale_rate_index);
}
/* Update this rate accounting for as many retries
* as was used for it (per current_count) */
iwl3945_collect_tx_data(rs_sta,
&rs_sta->win[scale_rate_index],
0, current_count);
IWL_DEBUG_RATE("Update rate %d for %d retries.\n",
scale_rate_index, current_count);
retries -= current_count;
if (retries)
scale_rate_index =
rs_adjust_next_rate(priv, scale_rate_index);
}
/* Update the last index window with success/failure based on ACK */
IWL_DEBUG_RATE("Update rate %d with %s.\n",
last_index,
(info->flags & IEEE80211_TX_STAT_ACK) ?
"success" : "failure");
iwl3945_collect_tx_data(rs_sta,
&rs_sta->win[last_index],
info->flags & IEEE80211_TX_STAT_ACK, 1);
/* We updated the rate scale window -- if its been more than
* flush_time since the last run, schedule the flush
* again */
spin_lock_irqsave(&rs_sta->lock, flags);
if (!rs_sta->flush_pending &&
time_after(jiffies, rs_sta->last_partial_flush +
rs_sta->flush_time)) {
rs_sta->flush_pending = 1;
mod_timer(&rs_sta->rate_scale_flush,
jiffies + rs_sta->flush_time);
}
spin_unlock_irqrestore(&rs_sta->lock, flags);
IWL_DEBUG_RATE("leave\n");
return;
}
static u16 iwl3945_get_adjacent_rate(struct iwl3945_rs_sta *rs_sta,
u8 index, u16 rate_mask, enum ieee80211_band band)
{
u8 high = IWL_RATE_INVALID;
u8 low = IWL_RATE_INVALID;
/* 802.11A walks to the next literal adjacent rate in
* the rate table */
if (unlikely(band == IEEE80211_BAND_5GHZ)) {
int i;
u32 mask;
/* Find the previous rate that is in the rate mask */
i = index - 1;
for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
if (rate_mask & mask) {
low = i;
break;
}
}
/* Find the next rate that is in the rate mask */
i = index + 1;
for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
if (rate_mask & mask) {
high = i;
break;
}
}
return (high << 8) | low;
}
low = index;
while (low != IWL_RATE_INVALID) {
if (rs_sta->tgg)
low = iwl3945_rates[low].prev_rs_tgg;
else
low = iwl3945_rates[low].prev_rs;
if (low == IWL_RATE_INVALID)
break;
if (rate_mask & (1 << low))
break;
IWL_DEBUG_RATE("Skipping masked lower rate: %d\n", low);
}
high = index;
while (high != IWL_RATE_INVALID) {
if (rs_sta->tgg)
high = iwl3945_rates[high].next_rs_tgg;
else
high = iwl3945_rates[high].next_rs;
if (high == IWL_RATE_INVALID)
break;
if (rate_mask & (1 << high))
break;
IWL_DEBUG_RATE("Skipping masked higher rate: %d\n", high);
}
return (high << 8) | low;
}
/**
* rs_get_rate - find the rate for the requested packet
*
* Returns the ieee80211_rate structure allocated by the driver.
*
* The rate control algorithm has no internal mapping between hw_mode's
* rate ordering and the rate ordering used by the rate control algorithm.
*
* The rate control algorithm uses a single table of rates that goes across
* the entire A/B/G spectrum vs. being limited to just one particular
* hw_mode.
*
* As such, we can't convert the index obtained below into the hw_mode's
* rate table and must reference the driver allocated rate table
*
*/
static void rs_get_rate(void *priv_r, struct ieee80211_supported_band *sband,
struct ieee80211_sta *sta, void *priv_sta,
struct sk_buff *skb, struct rate_selection *sel)
{
u8 low = IWL_RATE_INVALID;
u8 high = IWL_RATE_INVALID;
u16 high_low;
int index;
struct iwl3945_rs_sta *rs_sta = priv_sta;
struct iwl3945_rate_scale_data *window = NULL;
int current_tpt = IWL_INV_TPT;
int low_tpt = IWL_INV_TPT;
int high_tpt = IWL_INV_TPT;
u32 fail_count;
s8 scale_action = 0;
unsigned long flags;
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
u16 fc, rate_mask;
struct iwl3945_priv *priv = (struct iwl3945_priv *)priv_r;
DECLARE_MAC_BUF(mac);
IWL_DEBUG_RATE("enter\n");
/* 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 || !priv_sta) {
IWL_DEBUG_RATE("leave: No STA priv data to update!\n");
sel->rate_idx = rate_lowest_index(sband, sta);
return;
}
rate_mask = sta->supp_rates[sband->band];
index = min(rs_sta->last_txrate_idx & 0xffff, IWL_RATE_COUNT - 1);
if (sband->band == IEEE80211_BAND_5GHZ)
rate_mask = rate_mask << IWL_FIRST_OFDM_RATE;
if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
!rs_sta->ibss_sta_added) {
u8 sta_id = iwl3945_hw_find_station(priv, hdr->addr1);
if (sta_id == IWL_INVALID_STATION) {
IWL_DEBUG_RATE("LQ: ADD station %s\n",
print_mac(mac, hdr->addr1));
sta_id = iwl3945_add_station(priv,
hdr->addr1, 0, CMD_ASYNC);
}
if (sta_id != IWL_INVALID_STATION)
rs_sta->ibss_sta_added = 1;
}
spin_lock_irqsave(&rs_sta->lock, flags);
if (rs_sta->start_rate != IWL_RATE_INVALID) {
index = rs_sta->start_rate;
rs_sta->start_rate = IWL_RATE_INVALID;
}
window = &(rs_sta->win[index]);
fail_count = window->counter - window->success_counter;
if (((fail_count <= IWL_RATE_MIN_FAILURE_TH) &&
(window->success_counter < IWL_RATE_MIN_SUCCESS_TH))) {
window->average_tpt = IWL_INV_TPT;
spin_unlock_irqrestore(&rs_sta->lock, flags);
IWL_DEBUG_RATE("Invalid average_tpt on rate %d: "
"counter: %d, success_counter: %d, "
"expected_tpt is %sNULL\n",
index,
window->counter,
window->success_counter,
rs_sta->expected_tpt ? "not " : "");
goto out;
}
window->average_tpt = ((window->success_ratio *
rs_sta->expected_tpt[index] + 64) / 128);
current_tpt = window->average_tpt;
high_low = iwl3945_get_adjacent_rate(rs_sta, index, rate_mask,
sband->band);
low = high_low & 0xff;
high = (high_low >> 8) & 0xff;
if (low != IWL_RATE_INVALID)
low_tpt = rs_sta->win[low].average_tpt;
if (high != IWL_RATE_INVALID)
high_tpt = rs_sta->win[high].average_tpt;
spin_unlock_irqrestore(&rs_sta->lock, flags);
scale_action = 1;
if ((window->success_ratio < IWL_RATE_DECREASE_TH) || !current_tpt) {
IWL_DEBUG_RATE("decrease rate because of low success_ratio\n");
scale_action = -1;
} else if ((low_tpt == IWL_INV_TPT) && (high_tpt == IWL_INV_TPT))
scale_action = 1;
else if ((low_tpt != IWL_INV_TPT) && (high_tpt != IWL_INV_TPT) &&
(low_tpt < current_tpt) && (high_tpt < current_tpt)) {
IWL_DEBUG_RATE("No action -- low [%d] & high [%d] < "
"current_tpt [%d]\n",
low_tpt, high_tpt, current_tpt);
scale_action = 0;
} else {
if (high_tpt != IWL_INV_TPT) {
if (high_tpt > current_tpt)
scale_action = 1;
else {
IWL_DEBUG_RATE
("decrease rate because of high tpt\n");
scale_action = -1;
}
} else if (low_tpt != IWL_INV_TPT) {
if (low_tpt > current_tpt) {
IWL_DEBUG_RATE
("decrease rate because of low tpt\n");
scale_action = -1;
} else
scale_action = 1;
}
}
if ((window->success_ratio > IWL_RATE_HIGH_TH) ||
(current_tpt > window->average_tpt)) {
IWL_DEBUG_RATE("No action -- success_ratio [%d] > HIGH_TH or "
"current_tpt [%d] > average_tpt [%d]\n",
window->success_ratio,
current_tpt, window->average_tpt);
scale_action = 0;
}
switch (scale_action) {
case -1:
if (low != IWL_RATE_INVALID)
index = low;
break;
case 1:
if (high != IWL_RATE_INVALID)
index = high;
break;
case 0:
default:
break;
}
IWL_DEBUG_RATE("Selected %d (action %d) - low %d high %d\n",
index, scale_action, low, high);
out:
rs_sta->last_txrate_idx = index;
if (sband->band == IEEE80211_BAND_5GHZ)
sel->rate_idx = rs_sta->last_txrate_idx - IWL_FIRST_OFDM_RATE;
else
sel->rate_idx = rs_sta->last_txrate_idx;
IWL_DEBUG_RATE("leave: %d\n", index);
}
static struct rate_control_ops rs_ops = {
.module = NULL,
.name = RS_NAME,
.tx_status = rs_tx_status,
.get_rate = rs_get_rate,
.rate_init = rs_rate_init,
.clear = rs_clear,
.alloc = rs_alloc,
.free = rs_free,
.alloc_sta = rs_alloc_sta,
.free_sta = rs_free_sta,
};
void iwl3945_rate_scale_init(struct ieee80211_hw *hw, s32 sta_id)
{
struct iwl3945_priv *priv = hw->priv;
s32 rssi = 0;
unsigned long flags;
struct iwl3945_rs_sta *rs_sta;
struct ieee80211_sta *sta;
struct iwl3945_sta_priv *psta;
IWL_DEBUG_RATE("enter\n");
rcu_read_lock();
sta = ieee80211_find_sta(hw, priv->stations[sta_id].sta.sta.addr);
psta = (void *) sta->drv_priv;
if (!sta || !psta) {
IWL_DEBUG_RATE("leave - no private rate data!\n");
rcu_read_unlock();
return;
}
rs_sta = psta->rs_sta;
spin_lock_irqsave(&rs_sta->lock, flags);
rs_sta->tgg = 0;
switch (priv->band) {
case IEEE80211_BAND_2GHZ:
/* TODO: this always does G, not a regression */
if (priv->active_rxon.flags & RXON_FLG_TGG_PROTECT_MSK) {
rs_sta->tgg = 1;
rs_sta->expected_tpt = iwl3945_expected_tpt_g_prot;
} else
rs_sta->expected_tpt = iwl3945_expected_tpt_g;
break;
case IEEE80211_BAND_5GHZ:
rs_sta->expected_tpt = iwl3945_expected_tpt_a;
break;
case IEEE80211_NUM_BANDS:
BUG();
break;
}
rcu_read_unlock();
spin_unlock_irqrestore(&rs_sta->lock, flags);
rssi = priv->last_rx_rssi;
if (rssi == 0)
rssi = IWL_MIN_RSSI_VAL;
IWL_DEBUG(IWL_DL_INFO | IWL_DL_RATE, "Network RSSI: %d\n", rssi);
rs_sta->start_rate = iwl3945_get_rate_index_by_rssi(rssi, priv->band);
IWL_DEBUG_RATE("leave: rssi %d assign rate index: "
"%d (plcp 0x%x)\n", rssi, rs_sta->start_rate,
iwl3945_rates[rs_sta->start_rate].plcp);
}
int iwl3945_rate_control_register(void)
{
return ieee80211_rate_control_register(&rs_ops);
}
void iwl3945_rate_control_unregister(void)
{
ieee80211_rate_control_unregister(&rs_ops);
}
Reference in a new issue View git blame Copy permalink