/* $NetBSD: ieee80211_amrr.c,v 1.2 2007/12/11 12:40:10 lukem Exp $ */
/* $OpenBSD: ieee80211_amrr.c,v 1.1 2006/06/17 19:07:19 damien Exp $ */
/*
* Copyright 2016 Hans Rosenfeld <rosenfeld@grumpf.hope-2000.org>
*/
/*
* Copyright (c) 2006
* Damien Bergamini <damien.bergamini@free.fr>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/sdt.h>
#include <net/if.h>
#include <sys/net80211.h>
#include <sys/net80211_amrr.h>
#include "net80211_impl.h"
#define is_success(amn) \
((amn)->amn_retrycnt < (amn)->amn_txcnt / 10)
#define is_failure(amn) \
((amn)->amn_retrycnt > (amn)->amn_txcnt / 3)
#define is_enough(amn) \
((amn)->amn_txcnt > 10)
#define is_min_rate(ni) \
((ni)->in_txrate == 0)
#define is_max_rate(ni) \
((ni)->in_txrate == (ni)->in_rates.ir_nrates - 1)
#define increase_rate(ni) \
((ni)->in_txrate++)
#define decrease_rate(ni) \
((ni)->in_txrate--)
#define reset_cnt(amn) \
do { (amn)->amn_txcnt = (amn)->amn_retrycnt = 0; \
_NOTE(CONSTCOND) } while (0)
void
ieee80211_amrr_node_init(struct ieee80211_amrr *amrr,
struct ieee80211_amrr_node *amn)
{
amn->amn_success = 0;
amn->amn_recovery = 0;
amn->amn_txcnt = amn->amn_retrycnt = 0;
amn->amn_success_threshold = amrr->amrr_min_success_threshold;
}
/*
* Update ni->in_txrate.
*/
void
ieee80211_amrr_choose(struct ieee80211_amrr *amrr, struct ieee80211_node *ni,
struct ieee80211_amrr_node *amn)
{
int need_change = 0;
uint8_t rate;
if (is_success(amn) && is_enough(amn)) {
amn->amn_success++;
if (amn->amn_success >= amn->amn_success_threshold &&
!is_max_rate(ni)) {
amn->amn_recovery = 1;
amn->amn_success = 0;
increase_rate(ni);
rate = ni->in_rates.ir_rates[ni->in_txrate] &
IEEE80211_RATE_VAL;
ieee80211_dbg(IEEE80211_MSG_XRATE,
"AMRR increasing rate %d (txcnt=%d retrycnt=%d)",
rate, amn->amn_txcnt, amn->amn_retrycnt);
DTRACE_PROBE4(amrr__increase__rate,
struct ieee80211_node *, ni,
uint8_t, rate,
uint_t, amn->amn_txcnt,
uint_t, amn->amn_retrycnt);
need_change = 1;
} else {
amn->amn_recovery = 0;
}
} else if (is_failure(amn)) {
amn->amn_success = 0;
if (!is_min_rate(ni)) {
if (amn->amn_recovery) {
amn->amn_success_threshold *= 2;
if (amn->amn_success_threshold >
amrr->amrr_max_success_threshold)
amn->amn_success_threshold =
amrr->amrr_max_success_threshold;
} else {
amn->amn_success_threshold =
amrr->amrr_min_success_threshold;
}
decrease_rate(ni);
rate = ni->in_rates.ir_rates[ni->in_txrate] &
IEEE80211_RATE_VAL;
ieee80211_dbg(IEEE80211_MSG_XRATE,
"AMRR decreasing rate %d (txcnt=%d retrycnt=%d)",
rate, amn->amn_txcnt, amn->amn_retrycnt);
DTRACE_PROBE4(amrr__decrease__rate,
struct ieee80211_node *, ni,
uint8_t, rate,
uint_t, amn->amn_txcnt,
uint_t, amn->amn_retrycnt);
need_change = 1;
}
amn->amn_recovery = 0;
}
if (is_enough(amn) || need_change)
reset_cnt(amn);
}