Ticket #1222: minstrel.patch

File minstrel.patch, 71.1 kB (added by mrenzmann, 5 years ago)
Patch for minstrel, originally added to #989

net80211/ieee80211_rate.c

old	new
46	46	#include <net80211/ieee80211_rate.h>
47	47
48	48	static const char *module_names[] = {
49		[IEEE80211_RATE_AMRR] = "ath_rate_amrr",
50		[IEEE80211_RATE_ONOE] = "ath_rate_onoe",
51		[IEEE80211_RATE_SAMPLE] = "ath_rate_sample"
	49	[IEEE80211_RATE_AMRR] = "ath_rate_amrr",
	50	[IEEE80211_RATE_MINSTREL] = "ath_rate_minstrel",
	51	[IEEE80211_RATE_ONOE] = "ath_rate_onoe",
	52	[IEEE80211_RATE_SAMPLE] = "ath_rate_sample"
52	53	};
53	54
54	55	/*

net80211/ieee80211_rate.h

old	new
69	69
70	70	enum {
71	71	IEEE80211_RATE_AMRR,
	72	IEEE80211_RATE_MINSTREL,
72	73	IEEE80211_RATE_ONOE,
73	74	IEEE80211_RATE_SAMPLE,
74	75	IEEE80211_RATE_MAX

ath_rate/Makefile

old new
4 4
5 5 TOP = $(obj)/..
6 6
7 obj-y := amrr/ onoe/ sample/
7 obj-y := amrr/ minstrel/ onoe/ sample/
8 8
9 9 include $(TOP)/Makefile.inc
10 10

ath_rate/minstrel/minstrel.h

old	new
	1	/*-
	2	* And then Indranet Technologies Ltd sponsored Derek Smithies to work
	3	* on this code. Derek Smithies (derek@indranet.co.nz) took parts of the
	4	* adm module and pasted it into this code base.
	5	*
	6	* This version of John Bicket's code takes the experimental approach one
	7	* step further.
	8	* When in auto rate mode, packets are sent at the selected rate.
	9	* The Hal asks for what alternative rate to use if the selected rate fails.
	10	* We provide the alternative rate from a random selection of 1.. max rate.
	11	* Given the probability of success, multiplied with the transmission time,
	12	* we can determine the rate which maximises packet throughput.
	13	*
	14	* Different rates are used for every remote node - some nodes will work
	15	* better on different rates.
	16	* Every second, a timer fires, to assess the throughput at each rate with
	17	* each remote node.
	18	* This timer will then determine the optimum rate for each remote node, based
	19	* on the performance figures.
	20	*
	21	* This code is called minstrel, because we have taken a wandering minstrel
	22	* apporoch. Wander aimlessly around the different rates, singing wherever
	23	* you can. And then, look at the performacnce, and make a choice.
	24	*
	25	* Enjoy. Derek Smithies.
	26	*
	27	***********************************************************************
	28	* Copyright (c) 2005 John Bicket
	29	* All rights reserved.
	30	*
	31	* Redistribution and use in source and binary forms, with or without
	32	* modification, are permitted provided that the following conditions
	33	* are met:
	34	* 1. Redistributions of source code must retain the above copyright
	35	* notice, this list of conditions and the following disclaimer,
	36	* without modification.
	37	* 2. Redistributions in binary form must reproduce at minimum a disclaimer
	38	* similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
	39	* redistribution must be conditioned upon including a substantially
	40	* similar Disclaimer requirement for further binary redistribution.
	41	* 3. Neither the names of the above-listed copyright holders nor the names
	42	* of any contributors may be used to endorse or promote products derived
	43	* from this software without specific prior written permission.
	44	*
	45	* Alternatively, this software may be distributed under the terms of the
	46	* GNU General Public License ("GPL") version 2 as published by the Free
	47	* Software Foundation.
	48	*
	49	* NO WARRANTY
	50	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	51	* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	52	* LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
	53	* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
	54	* THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
	55	* OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	56	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	57	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
	58	* IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	59	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
	60	* THE POSSIBILITY OF SUCH DAMAGES.
	61	*
	62	* $Id: minstrel.h 1441 2006-02-06 16:03:21Z mrenzmann $
	63	*/
	64
	65	/*
	66	* Defintions for the Atheros Wireless LAN controller driver.
	67	*/
	68	#ifndef _DEV_ATH_RATE_MINSTREL_H
	69	#define _DEV_ATH_RATE_MINSTREL_H
	70	#define MINSTREL_COLUMNS 10
	71
	72	/* per-device state */
	73	struct minstrel_softc {
	74	struct ath_ratectrl arc; /* base state */
	75
	76	#ifdef CONFIG_SYSCTL
	77	struct ctl_table_header *sysctl_header;
	78	struct ctl_table *sysctls;
	79	#endif
	80	struct ath_softc *sc;
	81	struct net_device *sc_dev;
	82
	83
	84	struct timer_list timer; /* periodic timer */
	85	int close_timer_now;
	86	};
	87
	88
	89	#define ATH_SOFTC_MINSTREL(sc) ((struct minstrel_softc *)sc->sc_rc)
	90
	91	struct rate_info {
	92	int rate;
	93	int rix;
	94	int rateCode;
	95	int shortPreambleRateCode;
	96	};
	97
	98
	99
	100	/* per-node state */
	101	struct minstrel_node {
	102	int static_rate_ndx; /User has bypassed dynamic selection. Fix on one rate /
	103	int num_rates;
	104	struct rate_info rates[IEEE80211_RATE_MAXSIZE];
	105
	106	unsigned perfect_tx_time[IEEE80211_RATE_MAXSIZE]; /* transmit time for 0 retries */
	107	unsigned retry_count[IEEE80211_RATE_MAXSIZE]; /The number of retrys permitted for this particular rate /
	108	unsigned retry_adjusted_count[IEEE80211_RATE_MAXSIZE]; /retry_count, but altered, depending on if this is a very poor (or very good) link /
	109	int current_rate;
	110
	111	u_int32_t rs_rateattempts[IEEE80211_RATE_MAXSIZE];
	112	u_int32_t rs_thisprob [IEEE80211_RATE_MAXSIZE];
	113	u_int32_t rs_ratesuccess [IEEE80211_RATE_MAXSIZE];
	114	u_int32_t rs_lastrateattempts[IEEE80211_RATE_MAXSIZE];
	115	u_int32_t rs_lastratesuccess [IEEE80211_RATE_MAXSIZE];
	116	u_int32_t rs_probability [IEEE80211_RATE_MAXSIZE]; /* units of parts per thousand */
	117	u_int64_t rs_succ_hist [IEEE80211_RATE_MAXSIZE];
	118	u_int64_t rs_att_hist [IEEE80211_RATE_MAXSIZE];
	119
	120	u_int32_t rs_this_tp [IEEE80211_RATE_MAXSIZE]; /Throughput, each rate /
	121
	122	int is_sampling;
	123
	124	/** These four parameters are indexes into the current rate
	125	table, and are calculated in ath_rate_statistics(), which
	126	happens every time the timer for rate adjustment fires */
	127	int max_tp_rate; /* Has the current highest recorded throughput */
	128	int max_tp_rate2; /* Has the second highest recorded throughput */
	129	int max_prob_rate; /* This rate has the highest chance of success. */
	130
	131	/**These two variables are used to keep track of what
	132	percentage of packets have been used to do sample on.
	133	Thus,if ath_lookaround_rate is set to 10%, we can expect that
	134	sample_count
	135	------------ = 0.1
	136	sample_count + packet_count */
	137	int packet_count; /* The number of times we have
	138	sent a packet to this node. */
	139	int sample_count; /* The number of times we have
	140	sent a sample packet to this node */
	141
	142	/**The table that holds the sequence of rates that we use. In
	143	each column in the table, the rates we sample are provided
	144	in some "random" order. Each rate we sample occurs once in
	145	each column. There are several columns, so we sample the
	146	different rates in a different order each time. */
	147	u_int8_t rs_sampleTable[IEEE80211_RATE_MAXSIZE][MINSTREL_COLUMNS];
	148	int rs_sampleColumn;
	149	int rs_sampleIndex;
	150
	151	/**Random number generator is
	152	Rn+1 = (A*Rn) + B.
	153
	154	This Random number generator determines when we send a minstrel
	155	packet, or a packet at an optimal rate.*/
	156	int random_n;
	157	int a, b; /*Coefficients of the random thing /
	158	};
	159
	160
	161	#define ATH_NODE_MINSTREL(an) ((struct minstrel_node *)&an[1])
	162
	163
	164	#ifndef MIN
	165	#define MIN(a,b) ((a) < (b) ? (a) : (b))
	166	#endif
	167	#ifndef MAX
	168	#define MAX(a,b) ((a) > (b) ? (a) : (b))
	169	#endif
	170
	171	#if 0
	172	#define WIFI_CW_MIN 31
	173	#define WIFI_CW_MAX 1023
	174	#else
	175	#define WIFI_CW_MIN 3
	176	#define WIFI_CW_MAX 10
	177	#endif
	178
	179	struct ar5212_desc {
	180	/*
	181	* tx_control_0
	182	*/
	183	u_int32_t frame_len:12;
	184	u_int32_t reserved_12_15:4;
	185	u_int32_t xmit_power:6;
	186	u_int32_t rts_cts_enable:1;
	187	u_int32_t veol:1;
	188	u_int32_t clear_dest_mask:1;
	189	u_int32_t ant_mode_xmit:4;
	190	u_int32_t inter_req:1;
	191	u_int32_t encrypt_key_valid:1;
	192	u_int32_t cts_enable:1;
	193
	194	/*
	195	* tx_control_1
	196	*/
	197	u_int32_t buf_len:12;
	198	u_int32_t more:1;
	199	u_int32_t encrypt_key_index:7;
	200	u_int32_t frame_type:4;
	201	u_int32_t no_ack:1;
	202	u_int32_t comp_proc:2;
	203	u_int32_t comp_iv_len:2;
	204	u_int32_t comp_icv_len:2;
	205	u_int32_t reserved_31:1;
	206
	207	/*
	208	* tx_control_2
	209	*/
	210	u_int32_t rts_duration:15;
	211	u_int32_t duration_update_enable:1;
	212	u_int32_t xmit_tries0:4;
	213	u_int32_t xmit_tries1:4;
	214	u_int32_t xmit_tries2:4;
	215	u_int32_t xmit_tries3:4;
	216
	217	/*
	218	* tx_control_3
	219	*/
	220	u_int32_t xmit_rate0:5;
	221	u_int32_t xmit_rate1:5;
	222	u_int32_t xmit_rate2:5;
	223	u_int32_t xmit_rate3:5;
	224	u_int32_t rts_cts_rate:5;
	225	u_int32_t reserved_25_31:7;
	226
	227	/*
	228	* tx_status_0
	229	*/
	230	u_int32_t frame_xmit_ok:1;
	231	u_int32_t excessive_retries:1;
	232	u_int32_t fifo_underrun:1;
	233	u_int32_t filtered:1;
	234	u_int32_t rts_fail_count:4;
	235	u_int32_t data_fail_count:4;
	236	u_int32_t virt_coll_count:4;
	237	u_int32_t send_timestamp:16;
	238
	239	/*
	240	* tx_status_1
	241	*/
	242	u_int32_t done:1;
	243	u_int32_t seq_num:12;
	244	u_int32_t ack_sig_strength:8;
	245	u_int32_t final_ts_index:2;
	246	u_int32_t comp_success:1;
	247	u_int32_t xmit_antenna:1;
	248	u_int32_t reserved_25_31_x:7;
	249	} __packed;
	250
	251	#endif /* _DEV_ATH_RATE_MINSTEL_H */
	252
	253	/* The comment below is magic for those who use emacs to edit this file. */
	254	/* With the comment below, the tab key does auto indent to 8 spaces. */
	255
	256	/*
	257	* Local Variables:
	258	* mode:c
	259	* c-file-style:"linux"
	260	* c-basic-offset:8
	261	* End:
	262	*/

ath_rate/minstrel/minstrel.txt

old	new
	1
	2	Minstrel
	3
	4	Introduction
	5	==================================================================
	6	This code is called minstrel, because we have taken a wandering minstrel
	7	apporoch. Wander around the different rates, singing wherever you
	8	can. And then, look at the performacnce, and make a choice. Note that the
	9	wandering minstrel will always wander in directions where he/she feels he/she
	10	will get paid the best for his/her work.
	11
	12	The Minstrel autorate selection algorithm is an EWMA based algorithm and is
	13	derived from
	14	1)An initial rate module we released in 2005,
	15	http://sourceforge.net/mailarchive/forum.php?forum_id=33966&max_rows=25&style=flat&viewmonth=200501&viewday=5
	16
	17	2)the "sample" module in the madwifi-ng source tree.
	18
	19	The code released in 2005 had some algorithmic and implementation
	20	flaws (one of which was that it was based on the old madwifi codebase)
	21	and was shown to be unstable. Performance of the sample module is poor
	22	(http://www.madwifi.org/ticket/989), and we have observed similar
	23	issues.
	24
	25	We noted:
	26	1)The rate chosen by sample did not alter to match changes in the radio
	27	environment.
	28	2)Higher throughput (between two nodes) could often be achieved by fixing the
	29	bitrate of both nodes to some value.
	30	3)After a long period of operation, "sample" appeared to be stuck in a low
	31	data rate, and would not move to a higher data rate.
	32
	33	We examined the code in sample, and decided the best approach was a
	34	rewrite based on sample and the module we released in January 2005.
	35
	36	Theory of operation
	37	==================================================================
	38
	39	We defined the measure of successfulnes (of packet transmission) as
	40
	41	mega-bits-transmitted
	42	Prob_success_transmission * ----------------------
	43	elapsed time
	44
	45	This measure of successfulness will therefore adjust the transmission speed to
	46	get the maximum number of data bits through the radio interface. Further, it
	47	means that the 1mb/sec rate (which has a very high probability of successful
	48	transmission) will not be used in preference to the 11mb/sec rate.
	49
	50	We decided that the module should record the successfulness of all packets
	51	that are transmitted. From this data, the module has sufficient information to
	52	decide which packets are more successful than others. However, a variability
	53	element was required. We had to force the module to examine bit rates other
	54	than optimal. Consquently, some percent of the packets have to be sent at
	55	rates regarded as non optimal.
	56
	57	10 times a second (this frequency is alterable by changing the driver code)
	58	a timer fires, which evaluates the statistics table. EWMA calculations
	59	(described below) are used to process the success history of each rate. On
	60	completion of the calculation, a decision is made as to the rate which has the
	61	best throughput, second best throughput, and highest probability of success.
	62	This data is used for populating the retry chain during the next 100 ms.
	63
	64	As stated above, the minstrel algorithm collects statistics from all packet
	65	attempts. Minstrel spends a particular percentage of frames, doing "look
	66	arounds" i.e. randomly trying other rates, to gather statistics. The
	67	percentage of "look around" frames, is set at boot time via the module
	68	parameter "ath_lookaround_rate" and defaults to 10%. The distribution of
	69	lookaround frames is also randomised somewhat to avoid any potential
	70	"strobing" of lookarounds between similar nodes.
	71
	72	TCP theory tells us that each packet sent must be delivered in under 26ms. Any
	73	longer duration, and the TCP network layers will start to back off. A delay of
	74	26ms implies that there is congestion in the network, and that fewer packets
	75	should be injected to the device. Our conclusion was to adjust the retry chain
	76	of each packet so the retry chain was guaranteed to be finished in under 26ms.
	77
	78
	79	Retry Chain
	80	==================================================================
	81	The HAL provides a multirate retry chain - which consists of four
	82	segments. Each segment is an advisement to the HAL to try to send the current
	83	packet at some rate, with a fixed number of retry attempts. Once the packet is
	84	successfully transmitted, the remainder of the retry chain is
	85	ignored. Selection of the number of retry attempts was based on the desire to
	86	get the packet out in under 26ms, or fail. We provided a module parameter,
	87	ath_segment_size, which has units of micoseconds, and specifies the maximum
	88	duration one segment in the retry chain can last. This module parameter has a
	89	default of 6000. Our view is that a segment size of between 4000 and 6000
	90	seems to fit most situations.
	91
	92	There is some room for movement here - if the traffic is UDP then the limit of
	93	26ms for the retry chain length is "meaningless". However, one may argue that
	94	if the packet was not transmitted after some time period, it should
	95	fail. Further, one does expect UDP packets to fail in transmission. We leave
	96	it as an area for future improvement.
	97
	98
	99	The (re)try segment chain is calculated in two possible manners. If this
	100	packet is a normal trnamission packet (90% of packets are this) then the retry
	101	count is best throughput, next best throughput, best probability, lowest
	102	baserate. If it is a sample packet (10% of packets are this), then the retry
	103	chain is random lookaround, best throughput, best probability, lowest base
	104	rate. In tabular format:
	105
	106	Try \| lookaround rate \| Normal rate
	107	------------------------------------------------
	108	1 \| Random lookaround \| Best throughput
	109	2 \| Best throughput \| Next best throughput
	110	3 \| Best probability \| Best probability
	111	4 \| Lowest Baserate \| Lowest Baserate
	112
	113	The retry count is adjusted so that the transmission time for that section of
	114	the retry chain is less than 26 ms.
	115
	116	After some discussion, we have adjusted the code so that the lowest rate is
	117	never used for the lookaround packet. Our view is that since this rate is used
	118	for management packets, this rate must be working. - Alternatively, the link
	119	is set up with management packets, data packets are acknowledged with
	120	management packets. Should the lowest rate stop working, the link is going to
	121	die reasonably soon.
	122
	123	Analysis of information in the /proc/net/madwifi/athX/rate_info file
	124	showed that the system was sampling too hard at some rates. For those
	125	rates that never work (54mb, 500m range) there is no point in sending
	126	10 sample packets (<6ms time). Consequently, for the very very low
	127	probability rates, we sample at most twice.
	128
	129
	130	EWMA
	131	==================================================================
	132
	133	The EWMA calculation is carried out 10 times a second, and is run for each
	134	rate. This calculation has a smoothing effect, so that new results have
	135	a reasonable (but not large) influence on the selected rate. However, with
	136	time, a series of new results in some particular direction will predominate.
	137	Given this smoothing, we can use words like inertia to describe the EWMA.
	138
	139	By "new results", we mean the results collected in the just completed 100ms
	140	interval. Old results are the EWMA scaling values from before the just
	141	completed 100ms interval.
	142
	143	EWMA scaling is set by the module parameter ath_ewma_level, and defaults to
	144	75%. A value of 0% means use only the new results, ignore the old results.
	145	A value of 99% means use the old results, with a tiny influence from the new
	146	results.
	147
	148
	149
	150	The calculation (performed for each rate, at each timer interrupt) of the
	151	probability of success is:
	152
	153	Psucces_this_time_interval * (100 - ath_ewma_level) + (Pold * ath_ewma_level)
	154	Pnew = ------------------------------------------------------------------------------
	155	100
	156
	157	number_packets_sent_successfully_this_rate_time_interval
	158	Psuccess_this_time_interval=--------------------------------------------------------
	159	number_packets_sent_this_rate_time_interval
	160
	161
	162	If no packets have been sent for a particular rate in a time interval, no
	163	calculation is carried out. The Psuccess value for this rate is not changed.
	164
	165	If the new time interval is the first time interval (the module has just been
	166	inserted), then Pnew is calculated from above with Pold set to 0.
	167
	168	The appropriate update interval was selected on the basis of choosing a comprimise
	169	between
	170	*collecting enough success/failure information to be meaningful
	171	*minimising the amount of cpu time spent do the updates
	172	*providing a means to recover quickly enough from a bad rate selection.
	173	The first two points are self explanatory. When there is a sudden change in the radio
	174	environment, an update interval of 100ms will mean that the rates marked as optimal are
	175	very quickly marked as poor. Consequently, the sudden change in radio environment will
	176	mean that minstrel will very quickly switch to a better rate.
	177
	178	A sudden change in the transmission probabilities will happen when the
	179	node has not transmitted any data for a while, and during that time
	180	the environment has changed. On starting to transmit, the probability
	181	of success at each rate will be quite different. The driver must adapt
	182	as quickly as possible, so as to not upset the higher TCP network
	183	layers.
	184
	185
	186
	187	Module Parameters
	188	====================================================
	189	The module has three parameters:
	190
	191	name default value purpose
	192	ath_ewma_level 75% rate of response to new data. A value of 100 is VERY responsive.
	193	ath_lookaround_rate 10% percent of packets sent at non optimal speed.
	194	ath_segment_size 6000 maximum duration of a retry segment (microseconds)
	195
	196
	197
	198
	199
	200	Test Network
	201	====================================================
	202	We used three computers in our test network. The first two, equipped with
	203	atheros cards running in adhoc mode. We used a program that sends a fixed
	204	number of TCP packets between computers, and reports on the data rate. The
	205	application reports on the data rate - at an application layer level, which is
	206	considerably lower than the level used in transmitting the packets.
	207
	208	The third computer had an atheros card also, but was running network monitor
	209	mode with ethereal. The monitor computer was used to see what data rates were
	210	used on the air. This computer was a form of "logging of the connection"
	211	without introducing any additional load on the first two computers.
	212
	213	It was from monitoring the results on the third computer that we started to
	214	get some confidence in the correctness of the code. We observed TCP
	215	backoffs (described above) on this box. There was much celebration when the
	216	throughput increased simply because the retry chain was finished in under 26
	217	ms.
	218
	219	Our view was that throughput between the two computers should be as
	220	close as possible (or better than) what can be achieved by setting
	221	both ends to fixed rates. Thus, if setting the both ends to fixed
	222	rates significantly increases the throughput, a reasonable conclusion
	223	is that a fault exists in the adaptive rate rate.
	224
	225	We recorded throughputs (with minstrel) that are within 10% of what is
	226	achieved with the experimentally determined optimum fixed rate.
	227
	228
	229	Notes on Timing
	230	====================================================
	231
	232	As noted above, Minstrel calculates the throughput for each rate. This
	233	calculation (using a packet of size 1200 bytes) determines the
	234	transmission time on the radio medium. In these calculations, we assume a
	235	contention window min and max value of 4 and 10 microseconds respectively.
	236
	237	Further, calculation of the transmission time is required so that we can
	238	guarantee a packet is transmitted (or dropped) in a minimum time period.
	239	The transmission time is used in determining how many times a packet
	240	is transmitted in each segment of the retry chain.
	241
	242	Indeed, the card will supply the cwmin/cwmax values directly
	243	iwpriv if_name get_cwmin <0\|1\|2\|3> <0\|1>
	244
	245	We have not made direct calls to determine cwmin/cwmax - this is an area
	246	for future work. Indeed, the cwmin/cwmax determination code could check to
	247	see if the user has altered these values with the appropriate iwpriv.
	248
	249	The contention window size does vary with traffic class. For example,
	250	video and voice have a contention window min of 3 and 2 microseconds
	251	respectively. Currently, minstrel does not check traffic class.
	252
	253	Calculating the throughputs based on traffic class and bit rate and
	254	variable packet size will significantly complicate the code and require
	255	many more sample packets. More sample packets will lower the throughput
	256	achieved. Thus, our view is that for this release, we should take a simple
	257	(but reasonable) approach that works stably and gives good throughputs.
	258
	259
	260	Values of cwin/cwmax of 4 and 10 microseconds are from
	261	IEEE Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer
	262	(PHY) specifications, Amendment : Medium Access Control (MAC) Enhancements for
	263	Quality of Service (QoS) P802.11e/D12.0, November 2004.
	264
	265
	266	Internal variable reporting
	267	====================================================
	268	The minstrel algorithm reports to the proc file system its internal
	269	statistics, which can be viewed as text. A sample output is below:
	270
	271	cat /proc/net/madwifi/ath0/rate_info
	272
	273
	274	rate data for node:: 00:02:6f:43:8c:7a
	275	rate throughput ewma prob this prob this succ/attempt success attempts
	276	1 0.0 0.0 0.0 0( 0) 0 0
	277	2 1.6 92.4 100.0 0( 0) 11 11
	278	5.5 3.9 89.9 100.0 0( 0) 11 11
	279	11 6.5 86.6 100.0 0( 0) 10 11
	280	6 4.8 92.4 100.0 0( 0) 11 11
	281	9 6.9 92.4 100.0 0( 0) 11 11
	282	12 9.0 92.4 100.0 0( 0) 11 11
	283	18 12.1 89.9 100.0 0( 0) 11 11
	284	24 15.5 92.4 100.0 0( 0) 11 11
	285	36 20.6 92.4 100.0 0( 0) 11 11
	286	t 48 23.6 89.9 100.0 0( 0) 12 12
	287	T P 54 27.1 96.2 96.2 0( 0) 996 1029
	288
	289
	290	Total packet count:: ideal 2344 lookaround 261
	291
	292	There is a separate table for each node in the neighbor table, which will
	293	appear similar to above.
	294
	295	The possible datarates for this node are listed in the column at the left. The
	296	calculated throughput and "ewma prob" are listed next, from which the rates
	297	used in retry chain are selected. The rates with the maximum throughput,
	298	second meximum throughput and maximum probability are indicated by the letters
	299	T, t, and P respectively.
	300
	301	The statistics gathered in the last 100ms time period are displayed in the
	302	"this prob" and "this succ/attempt" columns.
	303
	304	Finally, the number of packets transmitted at each rate, since module loading
	305	are listed in the last two columns. When interpreting the last four columns,
	306	note that we use the words "succ" or "success" to mean packets successfully
	307	sent from this node to the remote node. The driver determines success by
	308	analysing reports from the hal. The word "attempt" or "attempts" means the
	309	count of packets that we transmitted. Thus, the number in the success column
	310	will always be lower than the number in the attempts column.
	311
	312
	313	When the two nodes are brought closer together, the statistics start changing,
	314	and you see more successful attempts at the higher rates. The ewma prob at the
	315	higher rates increases and then most packets are conveyed at the higher rates.
	316
	317	When the rate is not on auto, but fixed, this table is still
	318	available, and will report the throughput etc for the current bit
	319	rate. Changing the rate from auto to fixed to auto will completely
	320	reset this table, and the operation of the minstrel module.
	321
	322
	323
	324
	325
	326
	327
	328
	329

ath_rate/minstrel/Makefile.kernel

old	new
	1	#
	2	# Makefile for the Minstrel rate control algorithm.
	3	#
	4	# $Id: //depot/sw/linuxsrc/src/802_11/madwifi/madwifi/ath_rate/minstrel/Makefile.kernel#1 $
	5	#
	6
	7	src ?= .
	8	srctree ?= .
	9
	10	TOP = $(srctree)/$(src)/../..
	11
	12	include $(TOP)/BuildCaps.inc
	13
	14	ATH= $(TOP)/ath
	15	ATH_HAL=$(TOP)/ath_hal
	16	COMPAT= $(TOP)/include
	17	HAL= $(TOP)/hal
	18
	19	INCS = -include $(COMPAT)/compat.h -I$(COMPAT)
	20	INCS += -I$(TOP) -I$(ATH) -I$(ATH_HAL) -I$(HAL)
	21	EXTRA_CFLAGS += $(INCS) $(COPTS)
	22
	23	ifneq ($(VERSION).$(PATCHLEVEL),2.4)
	24	obj-$(CONFIG_ATHEROS) += ath_rate_minstrel.o
	25	ath_rate_minstrel-objs := minstrel.o
	26	endif
	27
	28	ifeq ($(VERSION).$(PATCHLEVEL),2.4)
	29	obj-$(CONFIG_ATHEROS) := minstrel.o
	30
	31	export-objs := minstrel.o
	32	list-multi := ath_rate_minstrel.o
	33
	34	O_TARGET := ath_rate.o
	35	include $(TOPDIR)/Rules.make
	36	endif

ath_rate/minstrel/Makefile

old	new
	1	#
	2	# Copyright (c) 2004 Sam Leffler, Errno Consulting
	3	# Copyright (c) 2004 Video54 Technologies, Inc.
	4	# All rights reserved.
	5	#
	6	# Redistribution and use in source and binary forms, with or without
	7	# modification, are permitted provided that the following conditions
	8	# are met:
	9	# 1. Redistributions of source code must retain the above copyright
	10	# notice, this list of conditions and the following disclaimer,
	11	# without modification.
	12	# 2. Redistributions in binary form must reproduce at minimum a disclaimer
	13	# similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
	14	# redistribution must be conditioned upon including a substantially
	15	# similar Disclaimer requirement for further binary redistribution.
	16	# 3. Neither the names of the above-listed copyright holders nor the names
	17	# of any contributors may be used to endorse or promote products derived
	18	# from this software without specific prior written permission.
	19	#
	20	# Alternatively, this software may be distributed under the terms of the
	21	# GNU General Public License ("GPL") version 2 as published by the Free
	22	# Software Foundation.
	23	#
	24	# NO WARRANTY
	25	# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	26	# ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	27	# LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
	28	# AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
	29	# THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
	30	# OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	31	# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	32	# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
	33	# IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	34	# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
	35	# THE POSSIBILITY OF SUCH DAMAGES.
	36	#
	37
	38	#
	39	# Makefile for the Atheros Rate Control Support.
	40	#
	41	ifeq ($(obj),)
	42	obj= .
	43	endif
	44
	45	TOP = $(obj)/../..
	46
	47	obj-m += ath_rate_minstrel.o
	48	ath_rate_minstrel-objs := minstrel.o
	49
	50	include $(TOP)/Makefile.inc
	51
	52	INCS += -I$(TOP) -I$(ATH) -I$(ATH_HAL) -I$(HAL)
	53
	54	EXTRA_CFLAGS+= $(INCS) $(COPTS)
	55
	56	-include $(TOPDIR)/Rules.make
	57
	58	all:
	59	$(MAKE) -C $(KERNELPATH) SUBDIRS=$(shell pwd) modules
	60
	61	install:
	62	test -d $(DESTDIR)/$(KMODPATH) \|\| mkdir -p $(DESTDIR)/$(KMODPATH)
	63	cp ath_rate_minstrel.$(KMODSUF) $(DESTDIR)/$(KMODPATH)
	64
	65	clean:
	66	-rm -f ~ .o .ko .mod.c
	67	-rm -f .depend .version ..o.flags ..o.d ..o.cmd ..ko.cmd
	68	-rm -rf .tmp_versions
	69
	70	ath_rate_minstrel.o: $(ath_rate_minstrel-objs)
	71	$(LD) $(LDOPTS) -o ath_rate_minstrel.$(KMODSUF) -r $(ath_rate_minstrel-objs)

ath_rate/minstrel/minstrel.c

old	new
	1	/*-
	2	* And then Indranet Technologies Ltd sponsored Derek Smithies to work
	3	* on this code. Derek Smithies (derek@indranet.co.nz) took parts of the
	4	* adm module and pasted it into this code base.
	5	*
	6	* This version of John Bicket's code takes the experimental approach one
	7	* step further.
	8	* When in auto rate mode, packets are sent at the selected rate.
	9	* The Hal asks for what alternative rate to use if the selected rate fails.
	10	* We provide the alternative rate from a random selection of 1.. max rate.
	11	* Given the probability of success, multiplied with the transmission time,
	12	* we can determine the rate which maximises packet throughput.
	13	*
	14	* Different rates are used for every remote node - some nodes will work
	15	* better on different rates.
	16	* Every second, a timer fires, to assess the throughput at each rate with
	17	* each remote node.
	18	* This timer will then determine the optimum rate for each remote node, based
	19	* on the performance figures.
	20	*
	21	* This code is called minstrel, because we have taken a wandering minstrel
	22	* apporoch. Wander around the different rates, singing wherever
	23	* you can. And then, look at the performacnce, and make a choice.
	24	*
	25	* It is not an aimless search, there is some direction to the search
	26	* pattern. But then, the minstels of old only sung where they thought
	27	* they would get an income. Similarily, we direct thesearch a little.
	28	*
	29	* Enjoy. Derek Smithies.
	30	*
	31	***********************************************************************
	32	* Copyright (c) 2005 John Bicket
	33	* All rights reserved.
	34	*
	35	* Redistribution and use in source and binary forms, with or without
	36	* modification, are permitted provided that the following conditions
	37	* are met:
	38	* 1. Redistributions of source code must retain the above copyright
	39	* notice, this list of conditions and the following disclaimer,
	40	* without modification.
	41	* 2. Redistributions in binary form must reproduce at minimum a disclaimer
	42	* similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
	43	* redistribution must be conditioned upon including a substantially
	44	* similar Disclaimer requirement for further binary redistribution.
	45	* 3. Neither the names of the above-listed copyright holders nor the names
	46	* of any contributors may be used to endorse or promote products derived
	47	* from this software without specific prior written permission.
	48	*
	49	* Alternatively, this software may be distributed under the terms of the
	50	* GNU General Public License ("GPL") version 2 as published by the Free
	51	* Software Foundation.
	52	*
	53	* NO WARRANTY
	54	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	55	* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	56	* LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
	57	* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
	58	* THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
	59	* OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	60	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	61	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
	62	* IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	63	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
	64	* THE POSSIBILITY OF SUCH DAMAGES.
	65	*
	66	*
	67	* $Id: minstrel.c 1525 2006-04-23 21:05:57Z dyqith $
	68	*/
	69
	70
	71
	72	#ifndef AUTOCONF_INCLUDED
	73	#include <linux/config.h>
	74	#endif
	75
	76	#include <linux/version.h>
	77	#include <linux/module.h>
	78	#include <linux/init.h>
	79	#include <linux/skbuff.h>
	80	#include <linux/netdevice.h>
	81	#include <linux/random.h>
	82	#include <linux/delay.h>
	83	#include <linux/cache.h>
	84	#include <linux/sysctl.h>
	85	#include <linux/proc_fs.h>
	86	#include <linux/if_arp.h>
	87	#include <linux/net.h> // for net_random
	88	#include <linux/vmalloc.h>
	89
	90	#include <asm/uaccess.h>
	91
	92	#include <net80211/if_media.h>
	93	#include <net80211/ieee80211_var.h>
	94	#include <net80211/ieee80211_rate.h>
	95
	96	#include "if_athvar.h"
	97	#include "ah_desc.h"
	98
	99	#include "minstrel.h"
	100
	101	#define MINSTREL_DEBUG 10
	102	#ifdef MINSTREL_DEBUG
	103	enum {
	104	ATH_DEBUG_RATE = 0x00000010 /* rate control */
	105	};
	106	#define DPRINTF(sc, _fmt, ...) do { \
	107	/* printk(_fmt, __VA_ARGS__); */ \
	108	} while (0)
	109	#else
	110	#define DPRINTF(sc, _fmt, ...)
	111	#endif
	112
	113	#define ONE_SECOND (1000 * 1000) /* 1 second, or 1000 milliseconds, eternity in other words */
	114	/*
	115	* This file is an implementation of the SampleRate algorithm
	116	* in "Bit-rate Selection in Wireless Networks"
	117	* (http://www.pdos.lcs.mit.edu/papers/jbicket-ms.ps)
	118	*
	119	* SampleRate chooses the bit-rate it predicts will provide the most
	120	* throughput based on estimates of the expected per-packet
	121	* transmission time for each bit-rate. SampleRate periodically sends
	122	* packets at bit-rates other than the current one to estimate when
	123	* another bit-rate will provide better performance. SampleRate
	124	* switches to another bit-rate when its estimated per-packet
	125	* transmission time becomes smaller than the current bit-rate's.
	126	* SampleRate reduces the number of bit-rates it must sample by
	127	* eliminating those that could not perform better than the one
	128	* currently being used. SampleRate also stops probing at a bit-rate
	129	* if it experiences several successive losses.
	130	*
	131	* The difference between the algorithm in the thesis and the one in this
	132	* file is that the one in this file uses a ewma instead of a window.
	133	*
	134	* Also, this implementation tracks the average transmission time for
	135	* a few different packet sizes independently for each link.
	136	*
	137	*/
	138
	139	#include "release.h"
	140	static char *version = "1.2 (" RELEASE_VERSION ")";
	141	static char *dev_info = "ath_rate_minstrel";
	142
	143
	144	#define STALE_FAILURE_TIMEOUT_MS 10000
	145
	146	#define ENABLE_MRR 1
	147
	148	static int ath_timer_interval = (1000/10); /** every 1/10 second, timer runs */
	149
	150	/**10% of the time, send a packet at something other than the optimal rate, which fills
	151	the statistics tables nicely. This percentage is applied to the first packet of the
	152	multi rate retry chain. */
	153	static int ath_lookaround_rate = 10;
	154	static int ath_ewma_level = 75;
	155	static int ath_segment_size = 6000;
	156	static void ath_rate_ctl_reset(struct ath_softc , struct ieee80211_node );
	157
	158	/**Calculate the throughput and probability of success for each node
	159	we are talking on, based on the statistics collected during the
	160	last timer period. */
	161	static void ath_rate_statistics(void arg, struct ieee80211_node ni);
	162
	163
	164	#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,52))
	165	MODULE_PARM(ath_lookaround_rate, "i");
	166	MODULE_PARM(ath_ewma_level, "i");
	167	MODULE_PARM(ath_segment_size, "i");
	168	#else
	169	#include <linux/moduleparam.h>
	170	module_param(ath_lookaround_rate, int, 10);
	171	module_param(ath_ewma_level, int, 75);
	172	module_param(ath_segment_size, int, 6000);
	173	#endif
	174	MODULE_PARM_DESC(ath_lookaround_rate, " % of packets sent to fill statistics table (10) ");
	175	MODULE_PARM_DESC(ath_ewma_level, " scaling % used in ewma rolloff calculations (75) ");
	176	MODULE_PARM_DESC(ath_segment_size, " max duration of time to spend in either of the first two mrr segments (6000)");
	177
	178
	179
	180	static void
	181	ath_timer_function(unsigned long data);
	182
	183
	184	static __inline int
	185	rate_to_ndx(struct minstrel_node *sn, int rate)
	186	{
	187	int x = 0;
	188	for (x = 0; x < sn->num_rates; x++)
	189	if (sn->rates[x].rate == rate)
	190	return x;
	191	return -1;
	192	}
	193
	194	/*
	195	* Calculate the transmit duration of a frame.
	196	*/
	197	static unsigned
	198	calc_usecs_unicast_packet(struct ath_softc *sc, int length,
	199	int rix, int short_retries, int long_retries)
	200	{
	201	const HAL_RATE_TABLE *rt = sc->sc_currates;
	202	int rts, cts;
	203
	204	unsigned t_slot = 20;
	205	unsigned t_difs = 50;
	206	unsigned t_sifs = 10;
	207	struct ieee80211com *ic = &sc->sc_ic;
	208	int tt = 0;
	209	int x = 0;
	210	int cw = WIFI_CW_MIN;
	211	int cix = rt->info[rix].controlRate;
	212	KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));
	213
	214	if (!rt->info[rix].rateKbps) {
	215	printk(KERN_WARNING "rix %d (%d) bad ratekbps %d mode %u\n",
	216	rix, rt->info[rix].dot11Rate,
	217	rt->info[rix].rateKbps,
	218	sc->sc_curmode);
	219	return 0;
	220	}
	221	/*
	222	* XXX getting mac/phy level timings should be fixed for turbo
	223	* rates, and there is probably a way to get this from the
	224	* hal...
	225	*/
	226	switch (rt->info[rix].phy) {
	227	case IEEE80211_T_OFDM:
	228	t_slot = 9;
	229	t_sifs = 16;
	230	t_difs = 28;
	231	/* fall through */
	232	case IEEE80211_T_TURBO:
	233	t_slot = 9;
	234	t_sifs = 8;
	235	t_difs = 28;
	236	break;
	237	case IEEE80211_T_DS:
	238	/* fall through to default */
	239	default:
	240	/* pg 205 ieee.802.11.pdf */
	241	t_slot = 20;
	242	t_difs = 50;
	243	t_sifs = 10;
	244	}
	245
	246	rts = cts = 0;
	247
	248	if ((ic->ic_flags & IEEE80211_F_USEPROT) &&
	249	rt->info[rix].phy == IEEE80211_T_OFDM) {
	250	if (ic->ic_protmode == IEEE80211_PROT_RTSCTS)
	251	rts = 1;
	252	else if (ic->ic_protmode == IEEE80211_PROT_CTSONLY)
	253	cts = 1;
	254
	255	cix = rt->info[sc->sc_protrix].controlRate;
	256	}
	257
	258	if (0 /length > ic->ic_rtsthreshold /)
	259	rts = 1;
	260
	261	if (rts \|\| cts) {
	262	int ctsrate = rt->info[cix].rateCode;
	263	int ctsduration = 0;
	264
	265	if (!rt->info[cix].rateKbps) {
	266	#if 0
	267	printk(KERN_WARNING "cix %d (%d) bad ratekbps %d mode %u\n",
	268	cix, rt->info[cix].dot11Rate,
	269	rt->info[cix].rateKbps,
	270	sc->sc_curmode);
	271	#endif
	272	return 0;
	273	}
	274
	275
	276	ctsrate \|= rt->info[cix].shortPreamble;
	277	if (rts) /* SIFS + CTS */
	278	ctsduration += rt->info[cix].spAckDuration;
	279
	280	ctsduration += ath_hal_computetxtime(sc->sc_ah,
	281	rt, length, rix, AH_TRUE);
	282
	283	if (cts) /* SIFS + ACK */
	284	ctsduration += rt->info[cix].spAckDuration;
	285
	286	tt += (short_retries + 1) * ctsduration;
	287	}
	288	tt += t_difs;
	289	tt += (long_retries+1)*(t_sifs + rt->info[rix].spAckDuration);
	290	tt += (long_retries+1)*ath_hal_computetxtime(sc->sc_ah, rt, length,
	291	rix, AH_TRUE);
	292	for (x = 0; x <= short_retries + long_retries; x++) {
	293	cw = MIN(WIFI_CW_MAX, (cw + 1) * 2);
	294	tt += (t_slot * cw / 2);
	295	}
	296	return tt;
	297	}
	298
	299	static void
	300	ath_rate_node_init(struct ath_softc sc, struct ath_node an)
	301	{
	302	/* NB: assumed to be zero'd by caller */
	303	ath_rate_ctl_reset(sc, &an->an_node);
	304	}
	305
	306
	307	static void
	308	ath_rate_node_cleanup(struct ath_softc sc, struct ath_node an)
	309	{
	310	}
	311
	312	#if 0
	313	static void
	314	ath_rate_node_copy(struct ath_softc *sc,
	315	struct ath_node dst, const struct ath_node src)
	316	{
	317	struct minstrel_node *odst = ATH_NODE_MINSTREL(dst);
	318	const struct minstrel_node osrc = (const struct minstrel_node )&src[1];
	319	memcpy(odst, osrc, sizeof(struct minstrel_node));
	320	}
	321	#endif
	322
	323
	324	static void
	325	ath_rate_findrate(struct ath_softc sc, struct ath_node an,
	326	int shortPreamble, size_t frameLen,
	327	u_int8_t rix, int try0, u_int8_t *txrate)
	328	{
	329	struct minstrel_node *sn = ATH_NODE_MINSTREL(an);
	330	struct ieee80211com *ic = &sc->sc_ic;
	331	int ndx, mrr;
	332	int offset;
	333	if (sn->num_rates <= 0) {
	334	printk(KERN_WARNING "%s: no rates for %s?\n",
	335	dev_info,
	336	ether_sprintf(an->an_node.ni_macaddr));
	337	return;
	338	}
	339
	340	mrr = sc->sc_mrretry && !(ic->ic_flags & IEEE80211_F_USEPROT) && ENABLE_MRR;
	341
	342	if (sn->static_rate_ndx != -1) {
	343	ndx = sn->static_rate_ndx;
	344	} else {
	345	sn->packet_count++;
	346	sn->random_n = (sn->a*sn->random_n) + sn->b;
	347	offset = sn->random_n & 0xf;
	348	if ((((100 * sn->sample_count)/(sn->sample_count + sn->packet_count)) < ath_lookaround_rate) && (offset < 2)) {
	349	sn->sample_count++;
	350	sn->is_sampling = 1;
	351	if (sn->packet_count >= (10000)) {
	352	sn->sample_count = 0;
	353	sn->packet_count = 0;
	354	}
	355
	356	/* Don't look for slowest rate (i.e. slowest
	357	base rate) We must presume that the slowest
	358	rate works fine, or else other management
	359	frames will also be failing - therefore the
	360	link will soon be broken anyway. Indeed,
	361	the slowest rate was used to establish the
	362	link in the first place. */
	363	ndx = sn->rs_sampleTable[sn->rs_sampleIndex][sn->rs_sampleColumn];
	364	if (ndx >= sn->num_rates)
	365	ndx = 1;
	366	sn->rs_sampleIndex++;
	367	if (sn->rs_sampleIndex > (sn->num_rates - 2)) {
	368	sn->rs_sampleIndex = 0;
	369	sn->rs_sampleColumn++;
	370	if (sn->rs_sampleColumn == MINSTREL_COLUMNS)
	371	sn->rs_sampleColumn = 0;
	372	}
	373	} else
	374	ndx = sn->max_tp_rate;
	375
	376	}
	377
	378	if (sn->static_rate_ndx != -1)
	379	*try0 = ATH_TXMAXTRY;
	380	else
	381	*try0 = mrr ? sn->retry_adjusted_count[ndx] : ATH_TXMAXTRY;
	382
	383
	384
	385	KASSERT(ndx >= 0 && ndx < sn->num_rates,
	386	("%s: bad ndx (%d/%d) for %s?\n",
	387	dev_info, ndx, sn->num_rates,
	388	ether_sprintf(an->an_node.ni_macaddr)));
	389
	390	*rix = sn->rates[ndx].rix;
	391	if (shortPreamble)
	392	*txrate = sn->rates[ndx].shortPreambleRateCode;
	393	else
	394	*txrate = sn->rates[ndx].rateCode;
	395	}
	396
	397
	398	static void
	399	ath_rate_setupxtxdesc(struct ath_softc sc, struct ath_node an,
	400	struct ath_desc *ds, int shortPreamble, size_t frame_size, u_int8_t rix)
	401	{
	402	struct minstrel_node *sn = ATH_NODE_MINSTREL(an);
	403	int rc1, rc2, rc3; /* Index into the rate table, so for example, it is 0..11 */
	404	int rixc1, rixc2, rixc3; /* The actual bit rate used */
	405
	406	if (sn->is_sampling) {
	407	rc1 = sn->max_tp_rate;
	408	sn->is_sampling = 0;
	409	} else {
	410	rc1 = sn->max_tp_rate2;
	411	}
	412
	413	rc2 = sn->max_prob_rate;
	414	rc3 = 0;
	415
	416	KASSERT(rc1 >= 0 && rc1 < sn->num_rates,
	417	("%s: bad rc1 (%d/%d) for %s?\n",
	418	dev_info, rc1, sn->num_rates,
	419	ether_sprintf(an->an_node.ni_macaddr)));
	420
	421	KASSERT(rc2 >= 0 && rc2 < sn->num_rates,
	422	("%s: bad rc2 (%d/%d) for %s?\n",
	423	dev_info, rc2, sn->num_rates,
	424	ether_sprintf(an->an_node.ni_macaddr)));
	425
	426	KASSERT(rc3 >= 0 && rc3 < sn->num_rates,
	427	("%s: bad rc3 (%d/%d) for %s?\n",
	428	dev_info, rc3, sn->num_rates,
	429	ether_sprintf(an->an_node.ni_macaddr)));
	430
	431
	432	if (shortPreamble) {
	433	rixc1 = sn->rates[rc1].shortPreambleRateCode;
	434	rixc2 = sn->rates[rc2].shortPreambleRateCode;
	435	rixc3 = sn->rates[rc3].shortPreambleRateCode;
	436	} else {
	437	rixc1 = sn->rates[rc1].rateCode;
	438	rixc2 = sn->rates[rc2].rateCode;
	439	rixc3 = sn->rates[rc3].rateCode;
	440	}
	441
	442	ath_hal_setupxtxdesc(sc->sc_ah, ds,
	443	rixc1, sn->retry_adjusted_count[rc1], /* series 1 */
	444	rixc2, sn->retry_adjusted_count[rc2], /* series 2 */
	445	rixc3, sn->retry_adjusted_count[rc3] /* series 3 */
	446	);
	447	}
	448
	449
	450
	451
	452	static void
	453	ath_rate_tx_complete(struct ath_softc *sc,
	454	struct ath_node an, const struct ath_desc ds)
	455	{
	456	struct minstrel_node *sn = ATH_NODE_MINSTREL(an);
	457	struct ieee80211com *ic = &sc->sc_ic;
	458	const struct ar5212_desc ads = (const struct ar5212_desc )&ds->ds_ctl0;
	459	int final_rate = 0;
	460	int tries = 0;
	461	int ndx = -1;
	462	int mrr;
	463	int final_ndx;
	464	int rate0, tries0, ndx0;
	465	int rate1, tries1, ndx1;
	466	int rate2, tries2, ndx2;
	467	int rate3, tries3, ndx3;
	468	/* This is the index in the retry chain we finish at.
	469	With no retransmits, it is always 0.
	470	int finalTSIdx = ads->final_ts_index;
	471	*/
	472	final_rate = sc->sc_hwmap[ds->ds_txstat.ts_rate &~ HAL_TXSTAT_ALTRATE].ieeerate;
	473	final_ndx = rate_to_ndx(sn, final_rate);
	474	if (final_ndx >= sn->num_rates) {
	475	printk(KERN_ERR "final ndx too high\n");
	476	final_ndx = 0;
	477	}
	478	if (final_ndx < 0) {
	479	printk(KERN_ERR "final ndx too low\n");
	480	final_ndx = 0;
	481	}
	482
	483	/* tries is the total number of times we have endeavoured to
	484	send this packet, and is a sum of the #attempts at each
	485	level in the multi rate retry chain */
	486	tries = ds->ds_txstat.ts_shortretry + ds->ds_txstat.ts_longretry + 1;
	487
	488	if (sn->num_rates <= 0) {
	489	DPRINTF(sc, "%s: %s %s no rates yet\n", dev_info,
	490	ether_sprintf(an->an_node.ni_macaddr), __func__);
	491	return;
	492	}
	493
	494	if (!ds->ds_txstat.ts_status) /Success when sending a packet/
	495	sn->rs_ratesuccess[final_ndx]++;
	496
	497	mrr = sc->sc_mrretry && !(ic->ic_flags & IEEE80211_F_USEPROT) && ENABLE_MRR;
	498
	499	if (!mrr) {
	500	if (ndx >= 0 && ndx < sn->num_rates) {
	501	sn->rs_rateattempts[ndx]++;/* only one rate was used */
	502	}
	503	return;
	504	}
	505
	506
	507
	508
	509
	510	/**Now, query the hal/hardware to find out the contents of the multirate retry chain.
	511	If we have it set to 6,3,2,2, this call will always return 6,3,2,2. For some packets, we can
	512	get a mrr of 0, -1, -1, -1, which indicates there is no chain installed for that packet */
	513	rate0 = sc->sc_hwmap[ads->xmit_rate0].ieeerate;
	514	tries0 = ads->xmit_tries0;
	515	ndx0 = rate_to_ndx(sn, rate0);
	516
	517	rate1 = sc->sc_hwmap[ads->xmit_rate1].ieeerate;
	518	tries1 = ads->xmit_tries1;
	519	ndx1 = rate_to_ndx(sn, rate1);
	520
	521	rate2 = sc->sc_hwmap[ads->xmit_rate2].ieeerate;
	522	tries2 = ads->xmit_tries2;
	523	ndx2 = rate_to_ndx(sn, rate2);
	524
	525	rate3 = sc->sc_hwmap[ads->xmit_rate3].ieeerate;
	526	tries3 = ads->xmit_tries3;
	527	ndx3 = rate_to_ndx(sn, rate3);
	528
	529	sn->rs_rateattempts[ndx0] += MIN(tries, tries0);
	530	if (tries <= tries0)
	531	return;
	532
	533	if (tries1 < 0)
	534	return;
	535	tries = tries - tries0;
	536	sn->rs_rateattempts[ndx1] += MIN(tries, tries1);
	537	if (tries <= tries1)
	538	return;
	539
	540	if (tries2 < 0)
	541	return;
	542	tries = tries - tries1;
	543	sn->rs_rateattempts[ndx2] += MIN(tries, tries2);
	544	if (tries <= tries2)
	545	return;
	546
	547	if (tries3 < 0)
	548	return;
	549	tries = tries - tries2;
	550	sn->rs_rateattempts[ndx3] += MIN(tries, tries3);
	551	}
	552
	553
	554	static void
	555	ath_rate_newassoc(struct ath_softc sc, struct ath_node an, int isnew)
	556	{
	557	DPRINTF(sc, "%s: %s %s\n", dev_info,
	558	ether_sprintf(an->an_node.ni_macaddr), __func__);
	559	if (isnew)
	560	ath_rate_ctl_reset(sc, &an->an_node);
	561	}
	562
	563	static void
	564	ath_fill_sample_table(struct minstrel_node *sn)
	565	{
	566	int num_sample_rates = sn->num_rates - 1;
	567	int i, column_index;
	568	int newIndex;
	569	u_int8_t random_bytes[12];
	570
	571	for(column_index = 0; column_index < MINSTREL_COLUMNS; column_index++) {
	572	for (i = 0; i <= IEEE80211_RATE_MAXSIZE; i++)
	573	sn->rs_sampleTable[i][column_index] = 0;
	574
	575	for (i = 0; i < num_sample_rates; i++) {
	576	get_random_bytes(random_bytes, 8);
	577	newIndex = (i + (int)(random_bytes[i & 7])) % num_sample_rates;
	578	if (newIndex < 0)
	579	newIndex = 2;
	580
	581	while (sn->rs_sampleTable[newIndex][column_index] != 0) {
	582	newIndex = ((int)(newIndex + 1)) % num_sample_rates;
	583	if (newIndex < 0)
	584	newIndex = 2;
	585	}
	586
	587	sn->rs_sampleTable[newIndex][column_index] = i + 1;
	588	}
	589	}
	590
	591	sn->rs_sampleColumn = 0;
	592	sn->rs_sampleIndex = 0;
	593
	594	/**Seed value to random number geenrator, which determines when we
	595	send a sample packet at some non optimal rate */
	596	sn->random_n = 1;
	597	sn->a = 1664525;
	598	sn->b = 1013904223;
	599	#if 0
	600	char rates[200];
	601	char *p;
	602	for(column_index = 0; column_index < MINSTREL_COLUMNS; column_index++) {
	603	p = rates + sprintf(rates, "rates :: %d ", column_index);
	604	for (i = 0; i < num_sample_rates; i++)
	605	p += sprintf(p, "%2d ", (int)sn->rs_sampleTable[i][column_index])
	606	;
	607	printk("%s\n", rates);
	608	};
	609	#endif
	610	}
	611
	612
	613
	614
	615	/*
	616	* Initialize the tables for a node.
	617	*/
	618	static void
	619	ath_rate_ctl_reset(struct ath_softc sc, struct ieee80211_node ni)
	620	{
	621	struct ath_node *an = ATH_NODE(ni);
	622	struct minstrel_node *sn = ATH_NODE_MINSTREL(an);
	623	struct ieee80211vap *vap = ni->ni_vap;
	624	const HAL_RATE_TABLE *rt = sc->sc_currates;
	625	int x;
	626	int retry_index, tx_time;
	627	int srate;
	628	sn->num_rates = 0;
	629	sn->max_tp_rate = 0;
	630	sn->max_tp_rate2 = 0;
	631	sn->max_prob_rate = 0;
	632	sn->packet_count = 0;
	633	sn->sample_count = 0;
	634	sn->is_sampling = 0;
	635
	636	if (rt == NULL) {
	637	printk(KERN_WARNING "no rates yet! mode %u\n", sc->sc_curmode);
	638	return;
	639	}
	640	sn->static_rate_ndx = -1;
	641
	642	sn->num_rates = ni->ni_rates.rs_nrates;
	643	for (x = 0; x < ni->ni_rates.rs_nrates; x++) {
	644
	645	sn->rs_rateattempts[x] = 0;
	646	sn->rs_thisprob [x] = 0;
	647	sn->rs_ratesuccess [x] = 0;
	648	sn->rs_lastrateattempts[x] = 0;
	649	sn->rs_lastratesuccess [x] = 0;
	650	sn->rs_probability [x] = 0;
	651	sn->rs_succ_hist [x] = 0;
	652	sn->rs_att_hist [x] = 0;
	653	sn->rs_this_tp [x] = 0;
	654
	655	sn->rates[x].rate = ni->ni_rates.rs_rates[x] & IEEE80211_RATE_VAL;
	656	sn->rates[x].rix = sc->sc_rixmap[sn->rates[x].rate];
	657	if (sn->rates[x].rix == 0xff) {
	658	DPRINTF(sc, "%s: %s ignore bogus rix at %d\n",
	659	dev_info, __func__, x);
	660	continue;
	661	}
	662	sn->rates[x].rateCode = rt->info[sn->rates[x].rix].rateCode;
	663	sn->rates[x].shortPreambleRateCode =
	664	rt->info[sn->rates[x].rix].rateCode \|
	665	rt->info[sn->rates[x].rix].shortPreamble;
	666	}
	667
	668	ath_fill_sample_table(sn);
	669
	670	ni->ni_txrate = 0;
	671	sn->num_rates = ni->ni_rates.rs_nrates;
	672
	673	if (sn->num_rates <= 0) {
	674	DPRINTF(sc, "%s: %s %s no rates (fixed %d) \n",
	675	dev_info, __func__, ether_sprintf(ni->ni_macaddr),
	676	vap->iv_fixed_rate);
	677	/* there are no rates yet we're done */
	678	return;
	679	}
	680
	681	if (vap->iv_fixed_rate != -1) {
	682	srate = sn->num_rates - 1;
	683
	684	/*
	685	* A fixed rate is to be used; ic_fixed_rate is an
	686	* index into the supported rate set. Convert this
	687	* to the index into the negotiated rate set for
	688	* the node. We know the rate is there because the
	689	* rate set is checked when the station associates.
	690	*/
	691	/* NB: the rate set is assumed sorted */
	692	for (; srate >= 0 && (ni->ni_rates.rs_rates[srate] & IEEE80211_RATE_VAL) != vap->iv_fixed_rate; srate--);
	693
	694	KASSERT(srate >= 0,
	695	("fixed rate %d not in rate set", vap->iv_fixed_rate));
	696
	697	sn->static_rate_ndx = srate;
	698	ni->ni_txrate = srate;
	699	DPRINTF(sc, "%s: %s %s fixed rate %d%sMbps\n",
	700	dev_info, __func__, ether_sprintf(ni->ni_macaddr),
	701	sn->rates[srate].rate / 2,
	702	(sn->rates[srate].rate % 0x1) ? ".5" : " ");
	703	return;
	704	}
	705
	706
	707	int ndx = 0;
	708
	709	for (x = 0; x < ni->ni_rates.rs_nrates; x++) {
	710	sn->rs_rateattempts [x] = 0;
	711	sn->rs_thisprob [x] = 0;
	712	sn->rs_ratesuccess [x] = 0;
	713	sn->rs_probability [x] = 0;
	714	sn->rs_lastrateattempts[x] = 0;
	715	sn->rs_lastratesuccess [x] = 0;
	716	sn->rs_succ_hist [x] = 0;
	717	sn->rs_att_hist [x] = 0;
	718	sn->perfect_tx_time [x] =
	719	calc_usecs_unicast_packet(sc, 1200,
	720	sn->rates[x].rix,
	721	0, 0);
	722
	723	sn->retry_count [x] = 1;
	724	sn->retry_adjusted_count[x] = 1;
	725	for (retry_index = 2; retry_index < 11; retry_index++) {
	726	tx_time = calc_usecs_unicast_packet(sc, 1200, sn->rates[x].rix, 0, retry_index);
	727	if (tx_time > ath_segment_size)
	728	break;
	729	sn->retry_count[x] = retry_index;
	730	sn->retry_adjusted_count[x] = retry_index;
	731	}
	732	}
	733
	734	// printk(KERN_ERR "Retry table for this node\n");
	735	// for (x = 0; x < ni->ni_rates.rs_nrates; x++)
	736	// printk(KERN_ERR "%2d %2d %6d \n",x, sn->retry_count[x], sn->perfect_tx_time[x]);
	737
	738	/* set the initial rate */
	739	for (ndx = sn->num_rates-1; ndx > 0; ndx--)
	740	if (sn->rates[ndx].rate <= 72)
	741	break;
	742	sn->current_rate = ndx;
	743
	744	ni->ni_txrate = sn->current_rate;
	745	}
	746
	747	static void
	748	ath_rate_cb(void arg, struct ieee80211_node ni)
	749	{
	750	ath_rate_ctl_reset(ni->ni_ic->ic_dev->priv, ni);
	751	}
	752
	753	/*
	754	* Reset the rate control state for each 802.11 state transition.
	755	*/
	756	static void
	757	ath_rate_newstate(struct ieee80211vap *vap, enum ieee80211_state newstate)
	758	{
	759	struct ieee80211com *ic = vap->iv_ic;
	760
	761	if (newstate == IEEE80211_S_RUN) {
	762	if (ic->ic_opmode != IEEE80211_M_STA) {
	763	/*
	764	* Sync rates for associated stations and neighbors.
	765	*/
	766	ieee80211_iterate_nodes(&ic->ic_sta, ath_rate_cb, NULL);
	767	}
	768	ath_rate_newassoc(ic->ic_dev->priv, ATH_NODE(vap->iv_bss), 1);
	769	}
	770	}
	771
	772
	773	static void
	774	ath_timer_function(unsigned long data)
	775	{
	776	struct minstrel_softc ssc = (struct minstrel_softc ) data;
	777	struct ath_softc *sc = ssc->sc;
	778	int interval;
	779	struct ieee80211com *ic;
	780
	781	struct net_device *dev = ssc->sc_dev;
	782	struct timer_list *timer;
	783	interval = ath_timer_interval;
	784
	785
	786	if (dev == NULL)
	787	printk(KERN_INFO "Dev is null in this timer \n");
	788
	789	if (sc == NULL)
	790	printk(KERN_INFO "sc is null in this timer\n");
	791
	792
	793	ic = &sc->sc_ic;
	794
	795	if (ssc->close_timer_now)
	796	return;
	797
	798	if (dev->flags & IFF_RUNNING) {
	799	sc->sc_stats.ast_rate_calls++;
	800
	801	if (ic->ic_opmode == IEEE80211_M_STA) {
	802	struct ieee80211vap *tmpvap;
	803	TAILQ_FOREACH(tmpvap, &ic->ic_vaps, iv_next) {
	804	ath_rate_statistics(sc, tmpvap->iv_bss);/* NB: no reference */
	805	}
	806	} else
	807	ieee80211_iterate_nodes(&ic->ic_sta, ath_rate_statistics, sc);
	808
	809	}
	810	if (ic->ic_opmode == IEEE80211_M_STA)
	811	interval = ath_timer_interval >> 1;
	812	else
	813	interval = ath_timer_interval;
	814
	815	timer = &(ssc->timer);
	816	if (timer == NULL)
	817	printk(KERN_INFO "timer is null - leave it\n");
	818
	819	timer->expires = jiffies + ((HZ * interval) / 1000);
	820	add_timer(timer);
	821	}
	822
	823	static void
	824	ath_rate_statistics(void arg, struct ieee80211_node ni)
	825	{
	826	struct ath_node *an;
	827	struct minstrel_node *rn;
	828	struct ieee80211_rateset *rs;
	829	int i, rate, old_rate;
	830	u_int32_t p;
	831	u_int32_t micro_secs;
	832	u_int32_t max_prob, index_max_prob;
	833	u_int32_t max_tp, index_max_tp, index_max_tp2;
	834	/* Rate control
	835	*/
	836
	837
	838	an = (struct ath_node *)ni;
	839	rn = ATH_NODE_MINSTREL(an);
	840	rs = &ni->ni_rates;
	841	old_rate = ni->ni_txrate;
	842	rate = old_rate;
	843
	844	/Calculate statistics for each date rate in the table /
	845	/micro_secs is the time to transmit 1200 bytes, or 9600 bits./
	846	for (i = 0; i < rs->rs_nrates; i++) {
	847	micro_secs = rn->perfect_tx_time[i];
	848	if (micro_secs == 0)
	849	micro_secs = ONE_SECOND;
	850
	851	if (rn->rs_rateattempts[i] != 0) {
	852	p = (rn->rs_ratesuccess[i]*18000)/rn->rs_rateattempts[i];
	853	rn->rs_succ_hist[i] += rn->rs_ratesuccess[i];
	854	rn->rs_att_hist[i] += rn->rs_rateattempts[i];
	855	rn->rs_thisprob[i] = p;
	856	p = ((p * (100 - ath_ewma_level)) + (rn->rs_probability[i] * ath_ewma_level))/100;
	857	rn->rs_probability[i] = p;
	858	rn->rs_this_tp[i] = p * (ONE_SECOND/micro_secs);
	859	rn->rs_lastratesuccess[i] = rn->rs_ratesuccess[i];
	860	rn->rs_lastrateattempts[i] = rn->rs_rateattempts[i];
	861	rn->rs_ratesuccess[i] = 0;
	862	rn->rs_rateattempts[i] = 0;
	863	} else {
	864	rn->rs_lastratesuccess[i] = 0;
	865	rn->rs_lastrateattempts[i] = 0;
	866	}
	867
	868	/* Sample less often below the 10% chance of success.
	869	Sample less often above the 95% chance of success.
	870	rn->rs_probability is in units of 0..18000(100%), which avoids rounding issues.*/
	871	if ((rn->rs_probability[i] > 17100) \|\| ( rn->rs_probability[i] < 1800)) {
	872	rn->retry_adjusted_count[i] = rn->retry_count[i]>> 1;
	873	if (rn->retry_adjusted_count[i] > 2)
	874	rn->retry_adjusted_count[i] = 2;
	875	} else
	876	rn->retry_adjusted_count[i] = rn->retry_count[i];
	877	if (rn->retry_adjusted_count[i] == 0)
	878	rn->retry_adjusted_count[i] = 1;
	879
	880	}
	881
	882	/*The High speed rates (e.g 54mbps) is checked last. If
	883	throughput is the same for two rates, we prefer the
	884	lower rate, as this has a better chance of success.*/
	885	max_prob = 0;
	886	index_max_prob = 0;
	887	max_tp = 0;
	888	index_max_tp = 0;
	889	index_max_tp2 = 0;
	890
	891	/**This code could have been moved up into the previous
	892	loop. More readable to have it here */
	893	for (i = 0; i < rs->rs_nrates; i++) {
	894
	895	if (max_tp <= rn->rs_this_tp[i]) {
	896	index_max_tp = i;
	897	max_tp = rn->rs_this_tp[i];
	898	}
	899
	900	if (max_prob <= rn->rs_probability[i]) {
	901	index_max_prob = i;
	902	max_prob = rn->rs_probability[i];
	903	}
	904	}
	905
	906	max_tp = 0;
	907	for (i = 0; i < rs->rs_nrates; i++) {
	908	if ((i != index_max_tp) && (max_tp <= rn->rs_this_tp[i])) {
	909	index_max_tp2 = i;
	910	max_tp = rn->rs_this_tp[i];
	911	}
	912	}
	913
	914	rn->max_tp_rate = index_max_tp;
	915	rn->max_tp_rate2 = index_max_tp2;
	916	rn->max_prob_rate = index_max_prob;
	917	rn->current_rate = index_max_tp;
	918	}
	919
	920
	921
	922	static struct ath_ratectrl *
	923	ath_rate_attach(struct ath_softc *sc)
	924	{
	925	struct minstrel_softc *osc;
	926	DPRINTF(sc, "%s: %s\n", dev_info, __func__);
	927
	928	_MOD_INC_USE(THIS_MODULE, return NULL);
	929	osc = kmalloc(sizeof(struct minstrel_softc), GFP_ATOMIC);
	930	if (osc == NULL) {
	931	_MOD_DEC_USE(THIS_MODULE);
	932	return NULL;
	933	}
	934
	935	osc->arc.arc_space = sizeof(struct minstrel_node);
	936	osc->arc.arc_vap_space = 0;
	937
	938	osc->close_timer_now = 0;
	939	init_timer(&osc->timer);
	940	osc->sc = sc;
	941	osc->sc_dev = sc->sc_dev;
	942	osc->timer.function = ath_timer_function;
	943	osc->timer.data = (unsigned long)osc;
	944
	945	osc->timer.expires = jiffies + HZ;
	946	add_timer(&osc->timer);
	947
	948	return &osc->arc;
	949	}
	950
	951
	952	static void
	953	ath_rate_detach(struct ath_ratectrl *arc)
	954	{
	955	struct minstrel_softc osc = (struct minstrel_softc ) arc;
	956	osc->close_timer_now = 1;
	957	del_timer(&osc->timer);
	958	kfree(osc);
	959	_MOD_DEC_USE(THIS_MODULE);
	960	}
	961
	962
	963	#ifdef CONFIG_SYSCTL
	964	static int
	965	ath_proc_read_nodes(struct ieee80211vap vap, char buf, int space)
	966	{
	967	char *p = buf;
	968	struct ieee80211_node *ni;
	969	struct ath_node *an;
	970	struct minstrel_node *odst;
	971	struct ieee80211_node_table *nt =
	972	(struct ieee80211_node_table *) &vap->iv_ic->ic_sta;
	973	int x = 0;
	974	int this_tp, this_prob, this_eprob;
	975
	976	TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
	977	/* Assume each node needs 1500 bytes */
	978	if ((buf + space) < (p + 1500)) {
	979	if ((buf + space) > (p + 100)) {
	980	p += sprintf(p, "out of room for node %s\n\n", ether_sprintf(ni->ni_macaddr));
	981	break;
	982	}
	983	printk("out of memeory to write tall of the nodes\n");
	984	break;
	985	}
	986	an = ATH_NODE(ni);
	987	odst = ATH_NODE_MINSTREL(an);
	988	/* Skip ourself */
	989	if (memcmp(vap->iv_myaddr, ni->ni_macaddr,
	990	IEEE80211_ADDR_LEN)==0) {
	991	continue;
	992	}
	993
	994	p += sprintf(p, "rate data for node:: %s\n", ether_sprintf(ni->ni_macaddr));
	995	p += sprintf(p, "rate throughput ewma prob this prob this succ/attempt success attempts\n");
	996	for (x = 0; x < odst->num_rates; x++) {
	997	p += sprintf(p, "%s",
	998	(x == odst->current_rate) ? "T" : " ");
	999
	1000	p += sprintf(p, "%s",
	1001	(x == odst->max_tp_rate2) ? "t" : " ");
	1002
	1003	p += sprintf(p, "%s",
	1004	(x == odst->max_prob_rate) ? "P" : " ");
	1005
	1006	p += sprintf(p, "%3d%s",
	1007	odst->rates[x].rate/2,
	1008	(odst->rates[x].rate & 0x1) != 0 ? ".5" : " ");
	1009
	1010	this_tp = ((odst->rs_this_tp[x] / 18000) * 96) >> 10;
	1011	this_prob = odst->rs_thisprob[x] / 18;
	1012	this_eprob = odst->rs_probability[x] / 18;
	1013	p += sprintf(p, " %6u.%1u %6u.%1u %6u.%1u %3u(%3u) %8llu %8llu\n",
	1014	this_tp/10, this_tp%10,
	1015	this_eprob/10, this_eprob%10,
	1016	this_prob/10, this_prob%10,
	1017	odst->rs_lastratesuccess[x],
	1018	odst->rs_lastrateattempts[x],
	1019	odst->rs_succ_hist[x],
	1020	odst->rs_att_hist[x]);
	1021	}
	1022	p += sprintf(p, "\n");
	1023
	1024	p += sprintf(p, "Total packet count:: ideal %d lookaround %d\n\n", odst->packet_count, odst->sample_count);
	1025	}
	1026
	1027	return (p - buf);
	1028	}
	1029
	1030	int
	1031	ath_proc_ratesample_open(struct inode inode, struct file file)
	1032	{
	1033	struct proc_ieee80211_priv *pv = NULL;
	1034	struct proc_dir_entry *dp = PDE(inode);
	1035	struct ieee80211vap *vap = dp->data;
	1036
	1037	if (!(file->private_data = kmalloc(sizeof(struct proc_ieee80211_priv),
	1038	GFP_KERNEL)))
	1039	return -ENOMEM;
	1040
	1041	/* intially allocate both read and write buffers */
	1042	pv = (struct proc_ieee80211_priv *) file->private_data;
	1043	memset(pv, 0, sizeof(struct proc_ieee80211_priv));
	1044	pv->rbuf = vmalloc(MAX_PROC_IEEE80211_SIZE);
	1045	if (!pv->rbuf) {
	1046	kfree(pv);
	1047	return -ENOMEM;
	1048	}
	1049	pv->wbuf = vmalloc(MAX_PROC_IEEE80211_SIZE);
	1050	if (!pv->wbuf) {
	1051	vfree(pv->rbuf);
	1052	kfree(pv);
	1053	return -ENOMEM;
	1054	}
	1055
	1056	memset(pv->wbuf, 0, MAX_PROC_IEEE80211_SIZE);
	1057	memset(pv->rbuf, 0, MAX_PROC_IEEE80211_SIZE);
	1058	pv->max_wlen = MAX_PROC_IEEE80211_SIZE;
	1059	pv->max_rlen = MAX_PROC_IEEE80211_SIZE;
	1060
	1061	/* now read the data into the buffer */
	1062	pv->rlen = ath_proc_read_nodes(vap, pv->rbuf, MAX_PROC_IEEE80211_SIZE);
	1063	return 0;
	1064	}
	1065
	1066	static struct file_operations ath_proc_ratesample_ops = {
	1067	.read = NULL,
	1068	.write = NULL,
	1069	.open = ath_proc_ratesample_open,
	1070	.release = NULL,
	1071	};
	1072
	1073	static void
	1074	ath_rate_dynamic_proc_register(struct ieee80211vap *vap)
	1075	{
	1076	/* Create proc entries for the rate control algorithm */
	1077	ieee80211_proc_vcreate(vap, &ath_proc_ratesample_ops, "rate_info");
	1078	}
	1079
	1080	#endif /* CONFIG_SYSCTL */
	1081
	1082
	1083
	1084	static struct ieee80211_rate_ops ath_rate_ops = {
	1085	.ratectl_id = IEEE80211_RATE_MINSTREL,
	1086	.node_init = ath_rate_node_init,
	1087	.node_cleanup = ath_rate_node_cleanup,
	1088	.findrate = ath_rate_findrate,
	1089	.setupxtxdesc = ath_rate_setupxtxdesc,
	1090	.tx_complete = ath_rate_tx_complete,
	1091	.newassoc = ath_rate_newassoc,
	1092	.newstate = ath_rate_newstate,
	1093	.attach = ath_rate_attach,
	1094	.detach = ath_rate_detach,
	1095	.dynamic_proc_register = ath_rate_dynamic_proc_register,
	1096	};
	1097
	1098
	1099	MODULE_AUTHOR("John Bicket/Derek Smithies");
	1100	MODULE_DESCRIPTION("Minstrel Rate bit-rate selection algorithm for Atheros devices");
	1101	#ifdef MODULE_VERSION
	1102	MODULE_VERSION(RELEASE_VERSION);
	1103	#endif
	1104	#ifdef MODULE_LICENSE
	1105	MODULE_LICENSE("Dual BSD/GPL");
	1106	#endif
	1107
	1108	static int __init ath_rate_minstrel_init(void)
	1109	{
	1110	printk(KERN_INFO "%s: %s\n", dev_info, version);
	1111	printk(KERN_ERR "\n");
	1112	printk(KERN_ERR "Minstrel automatic rate control algorithm.\n");
	1113	printk(KERN_ERR "\n");
	1114
	1115	printk(KERN_ERR "Look around rate set to %d%%\n", ath_lookaround_rate);
	1116	printk(KERN_ERR "EWMA rolloff level set to %d%%\n", ath_ewma_level);
	1117	printk(KERN_ERR "Max Segment size in the mrr set to %d us\n", ath_segment_size);
	1118
	1119	printk(KERN_ERR "\n");
	1120	return ieee80211_rate_register(&ath_rate_ops);
	1121	}
	1122	module_init(ath_rate_minstrel_init);
	1123
	1124	static void __exit ath_rate_minstrel_exit(void)
	1125	{
	1126	ieee80211_rate_unregister(&ath_rate_ops);
	1127	printk(KERN_INFO "%s: unloaded\n", dev_info);
	1128	}
	1129	module_exit(ath_rate_minstrel_exit);
	1130
	1131	/* The comment below is magic for those who use emacs to edit this file. */
	1132	/* With the comment below, the tab key does auto indent to 8 spaces. */
	1133
	1134	/*
	1135	* Local Variables:
	1136	* mode:c
	1137	* c-file-style:linux
	1138	* c-basic-offset:8
	1139	* End:
	1140	*/
	1141
	1142

patches/2.4/Config.in

old	new
2	2	if [ "$CONFIG_ATHEROS" = "y" ]; then
3	3
4	4	choice ' Atheros: Default Transmission Rate Control Algorithm' \
5		"Sample CONFIG_ATHEROS_RATE_DEFAULT_SAMPLE \
	5	"Minstrel CONFIG_ATHEROS_RATE_DEFAULT_MINSTREL \
	6	Sample CONFIG_ATHEROS_RATE_DEFAULT_SAMPLE \
6	7	Onoe CONFIG_ATHEROS_RATE_DEFAULT_ONOE \
7		AMRR CONFIG_ATHEROS_RATE_DEFAULT_AMRR" ~~Sample~~
	8	AMRR CONFIG_ATHEROS_RATE_DEFAULT_AMRR" Minstrel
8	9
9	10	if [ "$CONFIG_ATHEROS_RATE_DEFAULT_AMRR" = "y" ]; then
10	11	define_bool CONFIG_ATHEROS_RATE_AMRR y
…	…
30	31	CONFIG_ATHEROS_RATE_SAMPLE $CONFIG_ATHEROS
31	32	fi
32	33
	34	if [ "$CONFIG_ATHEROS_RATE_DEFAULT_MINSTREL" = "y" ]; then
	35	define_bool CONFIG_ATHEROS_RATE_MINSTREL y
	36	define_string CONFIG_ATHEROS_RATE_DEFAULT "minstrel"
	37	else
	38	dep_bool ' Minstrel Rate control algorithm' \
	39	CONFIG_ATHEROS_RATE_MINSTREL $CONFIG_ATHEROS
	40	fi
	41
33	42	fi

patches/2.6/Kconfig

old	new
19	19	choice
20	20	prompt "Atheros: Default Transmission Rate Control Algorithm"
21	21	depends on ATHEROS
22		default ATHEROS_RATE_DEFAULT_~~SAMPLE~~
	22	default ATHEROS_RATE_DEFAULT_MINSTREL
23	23	help
24	24	Select the rate control algorithm to be used by default. You
25	25	can select additional algorithms below.
…	…
36	36	bool "Sample"
37	37	select ATHEROS_RATE_SAMPLE
38	38
	39	config ATHEROS_RATE_DEFAULT_MINSTREL
	40	bool "Minstrel"
	41	select ATHEROS_RATE_MINSTREL
	42
39	43	endchoice
40	44
41	45	config ATHEROS_RATE_DEFAULT
…	…
43	47	default "amrr" if ATHEROS_RATE_DEFAULT_AMRR
44	48	default "onoe" if ATHEROS_RATE_DEFAULT_ONOE
45	49	default "sample" if ATHEROS_RATE_DEFAULT_SAMPLE
	50	default "minstrel" if ATHEROS_RATE_DEFAULT_MINSTREL
46	51
47	52	config ATHEROS_RATE_AMRR
48	53	bool "Adaptive Multi-Rate Retry control algorithm"
…	…
75	80	the one currently being used. SampleRate also stops probing at
76	81	a bitrate if it experiences several successive losses.
77	82
	83
	84	config ATHEROS_RATE_MINSTREL
	85	bool "A wandering minstrel rate control algorithm"
	86	depends on ATHEROS
	87	default y
	88	help
	89	Similar to the SampleRate code base, except that it is
	90	a)more carefully written
	91	b)shown to give a throughput similar to what can be obtained by
	92	manually fixing either end to fixed rates
	93	c)verified by monitoring the network traffic with an ieee80211
	94	enabled ethereal
	95	d)responds to network changes and does modify the rate accordingly.
	96	Thus, on moving the two nodes together/apart, the ideal rate will
	97	be changed as appropriate.
	98

patches/2.6/Makefile

old	new
	1	obj-$(CONFIG_ATHEROS_RATE_AMRR) += ath_rate/amrr/
	2	obj-$(CONFIG_ATHEROS_RATE_MINSTREL) += ath_rate/minstrel/
	3	obj-$(CONFIG_ATHEROS_RATE_ONOE) += ath_rate/onoe/
1	4	obj-$(CONFIG_ATHEROS_RATE_SAMPLE) += ath_rate/sample/
2		~~obj-$(CONFIG_ATHEROS_RATE_ONOE) += ath_rate/onoe/~~
3		~~obj-$(CONFIG_ATHEROS_RATE_AMRR) += ath_rate/amrr/~~
4	5	obj-$(CONFIG_ATHEROS) += ath/ ath_hal/ net80211/

INSTALL

old	new
83	83	point to the output directory where .config is located, not to the
84	84	sources.
85	85
86		MadWifi currently provides three different rate control algorithms,
87		ONOE, AMRR and SAMPLE. SAMPLE is the most advanced one and is used by
	86	MadWifi currently provides four different rate control algorithms,
	87	ONOE, AMRR, SAMPLE and MINSTREL. SAMPLE and MINSTREL are both very
	88	advanced, but MINSTREL is quite new. Consequently, SAMPLE is used by
88	89	default. In order to make MadWifi use e.g. AMRR instead, you have to
89	90	specify that as the module parameter e.g.
90	91

ath/if_ath.c

old	new
106	106	#ifdef CONFIG_ATHEROS_RATE_DEFAULT
107	107	#define DEF_RATE_CTL CONFIG_ATHEROS_RATE_DEFAULT
108	108	#else
109		#define DEF_RATE_CTL "~~sample~~"
	109	#define DEF_RATE_CTL "minstrel"
110	110	#endif
111	111
112	112	enum {
…	…
308	308	MODULE_PARM_DESC(xchanmode, "Enable/disable extended channel mode");
309	309	MODULE_PARM_DESC(rfkill, "Enable/disable RFKILL capability");
310	310	MODULE_PARM_DESC(autocreate, "Create ath device in [sta\|ap\|wds\|adhoc\|ahdemo\|monitor] mode. defaults to sta, use 'none' to disable");
311		MODULE_PARM_DESC(ratectl, "Rate control algorithm [amrr\|onoe\|sample], defaults to '" DEF_RATE_CTL "'");
	311	MODULE_PARM_DESC(ratectl, "Rate control algorithm [amrr\|minstrel\|onoe\|sample], defaults to '" DEF_RATE_CTL "'");
312	312
313	313	static int ath_debug = 0;
314	314	#ifdef AR_DEBUG
…	…
4409	4409	* handling, programs the sleep registers so the hardware
4410	4410	* will wake up in time to receive beacons, and configures
4411	4411	* the beacon miss handling so we'll receive a BMISS
4412		* interrupt when we stop seeing beacons from the AP
	4412	* interrupt when we stop seeing beacons from the AP
4413	4413	* we've associated with.
4414	4414	*/
4415	4415	static void
…	…
9039	9039	struct ath_softc *sc = dev->priv;
9040	9040	struct net_device_stats *stats = &sc->sc_devstats;
9041	9041
9042		/* update according to private statistics */
	9042	/* update according to private statistics */
9043	9043	stats->tx_errors = sc->sc_stats.ast_tx_xretries
9044	9044	+ sc->sc_stats.ast_tx_fifoerr
9045	9045	+ sc->sc_stats.ast_tx_filtered;

Download in other formats:

Original Format

old	new
4	4
5	5	TOP = $(obj)/..
6	6
7		obj-y := amrr/ onoe/ sample/
	7	obj-y := amrr/ minstrel/ onoe/ sample/
8	8
9	9	include $(TOP)/Makefile.inc
10	10

Ticket #1222: minstrel.patch

net80211/ieee80211_rate.c

net80211/ieee80211_rate.h

ath_rate/Makefile

ath_rate/minstrel/minstrel.h

ath_rate/minstrel/minstrel.txt

ath_rate/minstrel/Makefile.kernel

ath_rate/minstrel/Makefile

ath_rate/minstrel/minstrel.c

patches/2.4/Config.in

patches/2.6/Kconfig

patches/2.6/Makefile

INSTALL

ath/if_ath.c

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