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/*-
* Copyright (c) 2004 INRIA
* Copyright (c) 2002-2005 Sam Leffler, Errno Consulting
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer,
* without modification.
* 2. Redistributions in binary form must reproduce at minimum a disclaimer
* similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
* redistribution must be conditioned upon including a substantially
* similar Disclaimer requirement for further binary redistribution.
* 3. Neither the names of the above-listed copyright holders nor the names
* of any contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* NO WARRANTY
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
* OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
* IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGES.
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* AMRR rate control. See:
* http://www-sop.inria.fr/rapports/sophia/RR-5208.html
* "IEEE 802.11 Rate Adaptation: A Practical Approach" by
* Mathieu Lacage, Hossein Manshaei, Thierry Turletti
*/
#include "opt_inet.h"
#include "opt_wlan.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/sysctl.h>
#include <sys/module.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/errno.h>
#include <machine/bus.h>
#include <machine/resource.h>
#include <sys/bus.h>
#include <sys/socket.h>
#include <net/if.h>
#include <net/if_media.h>
#include <net/if_arp.h>
#include <net80211/ieee80211_var.h>
#include <net/bpf.h>
#ifdef INET
#include <netinet/in.h>
#include <netinet/if_ether.h>
#endif
#include <dev/ath/if_athvar.h>
#include <dev/ath/ath_rate/amrr/amrr.h>
#include <contrib/dev/ath/ah_desc.h>
static int ath_rateinterval = 1000; /* rate ctl interval (ms) */
static int ath_rate_max_success_threshold = 10;
static int ath_rate_min_success_threshold = 1;
static void ath_rate_update(struct ath_softc *, struct ieee80211_node *,
int rate);
static void ath_rate_ctl_start(struct ath_softc *, struct ieee80211_node *);
static void ath_rate_ctl(void *, struct ieee80211_node *);
void
ath_rate_node_init(struct ath_softc *sc, struct ath_node *an)
{
/* NB: assumed to be zero'd by caller */
}
void
ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an)
{
}
void
ath_rate_findrate(struct ath_softc *sc, struct ath_node *an,
int shortPreamble, size_t frameLen,
u_int8_t *rix, int *try0, u_int8_t *txrate)
{
struct amrr_node *amn = ATH_NODE_AMRR(an);
*rix = amn->amn_tx_rix0;
*try0 = amn->amn_tx_try0;
if (shortPreamble)
*txrate = amn->amn_tx_rate0sp;
else
*txrate = amn->amn_tx_rate0;
}
void
ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an,
struct ath_desc *ds, int shortPreamble, u_int8_t rix)
{
struct amrr_node *amn = ATH_NODE_AMRR(an);
ath_hal_setupxtxdesc(sc->sc_ah, ds
, amn->amn_tx_rate1sp, amn->amn_tx_try1 /* series 1 */
, amn->amn_tx_rate2sp, amn->amn_tx_try2 /* series 2 */
, amn->amn_tx_rate3sp, amn->amn_tx_try3 /* series 3 */
);
}
void
ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an,
const struct ath_buf *bf)
{
struct amrr_node *amn = ATH_NODE_AMRR(an);
const struct ath_tx_status *ts = &bf->bf_status.ds_txstat;
int sr = ts->ts_shortretry;
int lr = ts->ts_longretry;
int retry_count = sr + lr;
amn->amn_tx_try0_cnt++;
if (retry_count == 1) {
amn->amn_tx_try1_cnt++;
} else if (retry_count == 2) {
amn->amn_tx_try1_cnt++;
amn->amn_tx_try2_cnt++;
} else if (retry_count == 3) {
amn->amn_tx_try1_cnt++;
amn->amn_tx_try2_cnt++;
amn->amn_tx_try3_cnt++;
} else if (retry_count > 3) {
amn->amn_tx_try1_cnt++;
amn->amn_tx_try2_cnt++;
amn->amn_tx_try3_cnt++;
amn->amn_tx_failure_cnt++;
}
if (amn->amn_interval != 0 &&
ticks - amn->amn_ticks > amn->amn_interval) {
ath_rate_ctl(sc, &an->an_node);
amn->amn_ticks = ticks;
}
}
void
ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew)
{
if (isnew)
ath_rate_ctl_start(sc, &an->an_node);
}
static void
node_reset(struct amrr_node *amn)
{
amn->amn_tx_try0_cnt = 0;
amn->amn_tx_try1_cnt = 0;
amn->amn_tx_try2_cnt = 0;
amn->amn_tx_try3_cnt = 0;
amn->amn_tx_failure_cnt = 0;
amn->amn_success = 0;
amn->amn_recovery = 0;
amn->amn_success_threshold = ath_rate_min_success_threshold;
}
/**
* The code below assumes that we are dealing with hardware multi rate retry
* I have no idea what will happen if you try to use this module with another
* type of hardware. Your machine might catch fire or it might work with
* horrible performance...
*/
static void
ath_rate_update(struct ath_softc *sc, struct ieee80211_node *ni, int rate)
{
struct ath_node *an = ATH_NODE(ni);
struct amrr_node *amn = ATH_NODE_AMRR(an);
struct ieee80211vap *vap = ni->ni_vap;
const HAL_RATE_TABLE *rt = sc->sc_currates;
u_int8_t rix;
KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));
IEEE80211_NOTE(vap, IEEE80211_MSG_RATECTL, ni,
"%s: set xmit rate to %dM", __func__,
ni->ni_rates.rs_nrates > 0 ?
(ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL) / 2 : 0);
amn->amn_rix = rate;
/*
* Before associating a node has no rate set setup
* so we can't calculate any transmit codes to use.
* This is ok since we should never be sending anything
* but management frames and those always go at the
* lowest hardware rate.
*/
if (ni->ni_rates.rs_nrates > 0) {
ni->ni_txrate = ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL;
amn->amn_tx_rix0 = sc->sc_rixmap[ni->ni_txrate];
amn->amn_tx_rate0 = rt->info[amn->amn_tx_rix0].rateCode;
amn->amn_tx_rate0sp = amn->amn_tx_rate0 |
rt->info[amn->amn_tx_rix0].shortPreamble;
if (sc->sc_mrretry) {
amn->amn_tx_try0 = 1;
amn->amn_tx_try1 = 1;
amn->amn_tx_try2 = 1;
amn->amn_tx_try3 = 1;
if (--rate >= 0) {
rix = sc->sc_rixmap[
ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL];
amn->amn_tx_rate1 = rt->info[rix].rateCode;
amn->amn_tx_rate1sp = amn->amn_tx_rate1 |
rt->info[rix].shortPreamble;
} else {
amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0;
}
if (--rate >= 0) {
rix = sc->sc_rixmap[
ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL];
amn->amn_tx_rate2 = rt->info[rix].rateCode;
amn->amn_tx_rate2sp = amn->amn_tx_rate2 |
rt->info[rix].shortPreamble;
} else {
amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0;
}
if (rate > 0) {
/* NB: only do this if we didn't already do it above */
amn->amn_tx_rate3 = rt->info[0].rateCode;
amn->amn_tx_rate3sp =
amn->amn_tx_rate3 | rt->info[0].shortPreamble;
} else {
amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0;
}
} else {
amn->amn_tx_try0 = ATH_TXMAXTRY;
/* theorically, these statements are useless because
* the code which uses them tests for an_tx_try0 == ATH_TXMAXTRY
*/
amn->amn_tx_try1 = 0;
amn->amn_tx_try2 = 0;
amn->amn_tx_try3 = 0;
amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0;
amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0;
amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0;
}
}
node_reset(amn);
amn->amn_interval = ath_rateinterval;
if (vap->iv_opmode == IEEE80211_M_STA)
amn->amn_interval /= 2;
amn->amn_interval = (amn->amn_interval * hz) / 1000;
}
/*
* Set the starting transmit rate for a node.
*/
static void
ath_rate_ctl_start(struct ath_softc *sc, struct ieee80211_node *ni)
{
#define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL)
const struct ieee80211_txparam *tp = ni->ni_txparms;
int srate;
KASSERT(ni->ni_rates.rs_nrates > 0, ("no rates"));
if (tp == NULL || tp->ucastrate == IEEE80211_FIXED_RATE_NONE) {
/*
* No fixed rate is requested. For 11b start with
* the highest negotiated rate; otherwise, for 11g
* and 11a, we start "in the middle" at 24Mb or 36Mb.
*/
srate = ni->ni_rates.rs_nrates - 1;
if (sc->sc_curmode != IEEE80211_MODE_11B) {
/*
* Scan the negotiated rate set to find the
* closest rate.
*/
/* NB: the rate set is assumed sorted */
for (; srate >= 0 && RATE(srate) > 72; srate--)
;
}
} else {
/*
* A fixed rate is to be used; ic_fixed_rate is the
* IEEE code for this rate (sans basic bit). Convert this
* to the index into the negotiated rate set for
* the node. We know the rate is there because the
* rate set is checked when the station associates.
*/
/* NB: the rate set is assumed sorted */
srate = ni->ni_rates.rs_nrates - 1;
for (; srate >= 0 && RATE(srate) != tp->ucastrate; srate--)
;
}
/*
* The selected rate may not be available due to races
* and mode settings. Also orphaned nodes created in
* adhoc mode may not have any rate set so this lookup
* can fail. This is not fatal.
*/
ath_rate_update(sc, ni, srate < 0 ? 0 : srate);
#undef RATE
}
/*
* Examine and potentially adjust the transmit rate.
*/
static void
ath_rate_ctl(void *arg, struct ieee80211_node *ni)
{
struct ath_softc *sc = arg;
struct amrr_node *amn = ATH_NODE_AMRR(ATH_NODE (ni));
int rix;
#define is_success(amn) \
(amn->amn_tx_try1_cnt < (amn->amn_tx_try0_cnt/10))
#define is_enough(amn) \
(amn->amn_tx_try0_cnt > 10)
#define is_failure(amn) \
(amn->amn_tx_try1_cnt > (amn->amn_tx_try0_cnt/3))
rix = amn->amn_rix;
IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni,
"cnt0: %d cnt1: %d cnt2: %d cnt3: %d -- threshold: %d",
amn->amn_tx_try0_cnt, amn->amn_tx_try1_cnt, amn->amn_tx_try2_cnt,
amn->amn_tx_try3_cnt, amn->amn_success_threshold);
if (is_success (amn) && is_enough (amn)) {
amn->amn_success++;
if (amn->amn_success == amn->amn_success_threshold &&
rix + 1 < ni->ni_rates.rs_nrates) {
amn->amn_recovery = 1;
amn->amn_success = 0;
rix++;
IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni,
"increase rate to %d", rix);
} else {
amn->amn_recovery = 0;
}
} else if (is_failure (amn)) {
amn->amn_success = 0;
if (rix > 0) {
if (amn->amn_recovery) {
/* recovery failure. */
amn->amn_success_threshold *= 2;
amn->amn_success_threshold = min (amn->amn_success_threshold,
(u_int)ath_rate_max_success_threshold);
IEEE80211_NOTE(ni->ni_vap,
IEEE80211_MSG_RATECTL, ni,
"decrease rate recovery thr: %d",
amn->amn_success_threshold);
} else {
/* simple failure. */
amn->amn_success_threshold = ath_rate_min_success_threshold;
IEEE80211_NOTE(ni->ni_vap,
IEEE80211_MSG_RATECTL, ni,
"decrease rate normal thr: %d",
amn->amn_success_threshold);
}
amn->amn_recovery = 0;
rix--;
} else {
amn->amn_recovery = 0;
}
}
if (is_enough (amn) || rix != amn->amn_rix) {
/* reset counters. */
amn->amn_tx_try0_cnt = 0;
amn->amn_tx_try1_cnt = 0;
amn->amn_tx_try2_cnt = 0;
amn->amn_tx_try3_cnt = 0;
amn->amn_tx_failure_cnt = 0;
}
if (rix != amn->amn_rix) {
ath_rate_update(sc, ni, rix);
}
}
static void
ath_rate_sysctlattach(struct ath_softc *sc)
{
struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev);
struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev);
SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
"rate_interval", CTLFLAG_RW, &ath_rateinterval, 0,
"rate control: operation interval (ms)");
/* XXX bounds check values */
SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
"max_sucess_threshold", CTLFLAG_RW,
&ath_rate_max_success_threshold, 0, "");
SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
"min_sucess_threshold", CTLFLAG_RW,
&ath_rate_min_success_threshold, 0, "");
}
struct ath_ratectrl *
ath_rate_attach(struct ath_softc *sc)
{
struct amrr_softc *asc;
asc = malloc(sizeof(struct amrr_softc), M_DEVBUF, M_NOWAIT|M_ZERO);
if (asc == NULL)
return NULL;
asc->arc.arc_space = sizeof(struct amrr_node);
ath_rate_sysctlattach(sc);
return &asc->arc;
}
void
ath_rate_detach(struct ath_ratectrl *arc)
{
struct amrr_softc *asc = (struct amrr_softc *) arc;
free(asc, M_DEVBUF);
}
/*
* Module glue.
*/
static int
amrr_modevent(module_t mod, int type, void *unused)
{
switch (type) {
case MOD_LOAD:
if (bootverbose)
printf("ath_rate: <AMRR rate control algorithm> version 0.1\n");
return 0;
case MOD_UNLOAD:
return 0;
}
return EINVAL;
}
static moduledata_t amrr_mod = {
"ath_rate",
amrr_modevent,
0
};
DECLARE_MODULE(ath_rate, amrr_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
MODULE_VERSION(ath_rate, 1);
MODULE_DEPEND(ath_rate, wlan, 1, 1, 1);
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