diff options
| -rw-r--r-- | net/mac80211/Makefile | 11 | ||||
| -rw-r--r-- | net/mac80211/rc80211_pid.h | 242 | ||||
| -rw-r--r-- | net/mac80211/rc80211_pid_algo.c (renamed from net/mac80211/rc80211_pid.c) | 149 | ||||
| -rw-r--r-- | net/mac80211/rc80211_pid_debugfs.c | 223 |
4 files changed, 508 insertions, 117 deletions
diff --git a/net/mac80211/Makefile b/net/mac80211/Makefile index a375f0477da..06aea8009cd 100644 --- a/net/mac80211/Makefile +++ b/net/mac80211/Makefile @@ -1,10 +1,17 @@ obj-$(CONFIG_MAC80211) += mac80211.o mac80211-objs-$(CONFIG_MAC80211_LEDS) += ieee80211_led.o -mac80211-objs-$(CONFIG_MAC80211_DEBUGFS) += debugfs.o debugfs_sta.o debugfs_netdev.o debugfs_key.o mac80211-objs-$(CONFIG_NET_SCHED) += wme.o mac80211-objs-$(CONFIG_MAC80211_RC_SIMPLE) += rc80211_simple.o -mac80211-objs-$(CONFIG_MAC80211_RC_PID) += rc80211_pid.o +mac80211-objs-$(CONFIG_MAC80211_RC_PID) += rc80211_pid_algo.o + +mac80211-debugfs-objs-$(CONFIG_MAC80211_RC_PID) += rc80211_pid_debugfs.o +mac80211-objs-$(CONFIG_MAC80211_DEBUGFS) += \ + debugfs.o \ + debugfs_sta.o \ + debugfs_netdev.o \ + debugfs_key.o \ + $(mac80211-debugfs-objs-y) mac80211-objs := \ ieee80211.o \ diff --git a/net/mac80211/rc80211_pid.h b/net/mac80211/rc80211_pid.h new file mode 100644 index 00000000000..5d0056c1513 --- /dev/null +++ b/net/mac80211/rc80211_pid.h @@ -0,0 +1,242 @@ +/* + * Copyright 2007, Mattias Nissler <mattias.nissler@gmx.de> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#ifndef RC80211_PID_H +#define RC80211_PID_H + +/* Sampling period for measuring percentage of failed frames. */ +#define RC_PID_INTERVAL (HZ / 8) + +/* Exponential averaging smoothness (used for I part of PID controller) */ +#define RC_PID_SMOOTHING_SHIFT 3 +#define RC_PID_SMOOTHING (1 << RC_PID_SMOOTHING_SHIFT) + +/* Sharpening factor (used for D part of PID controller) */ +#define RC_PID_SHARPENING_FACTOR 0 +#define RC_PID_SHARPENING_DURATION 0 + +/* Fixed point arithmetic shifting amount. */ +#define RC_PID_ARITH_SHIFT 8 + +/* Fixed point arithmetic factor. */ +#define RC_PID_ARITH_FACTOR (1 << RC_PID_ARITH_SHIFT) + +/* Proportional PID component coefficient. */ +#define RC_PID_COEFF_P 15 +/* Integral PID component coefficient. */ +#define RC_PID_COEFF_I 9 +/* Derivative PID component coefficient. */ +#define RC_PID_COEFF_D 15 + +/* Target failed frames rate for the PID controller. NB: This effectively gives + * maximum failed frames percentage we're willing to accept. If the wireless + * link quality is good, the controller will fail to adjust failed frames + * percentage to the target. This is intentional. + */ +#define RC_PID_TARGET_PF (11 << RC_PID_ARITH_SHIFT) + +/* Rate behaviour normalization quantity over time. */ +#define RC_PID_NORM_OFFSET 3 + +/* Push high rates right after loading. */ +#define RC_PID_FAST_START 0 + +/* Arithmetic right shift for positive and negative values for ISO C. */ +#define RC_PID_DO_ARITH_RIGHT_SHIFT(x, y) \ + (x) < 0 ? -((-(x)) >> (y)) : (x) >> (y) + +enum rc_pid_event_type { + RC_PID_EVENT_TYPE_TX_STATUS, + RC_PID_EVENT_TYPE_RATE_CHANGE, + RC_PID_EVENT_TYPE_TX_RATE, + RC_PID_EVENT_TYPE_PF_SAMPLE, +}; + +union rc_pid_event_data { + /* RC_PID_EVENT_TX_STATUS */ + struct { + struct ieee80211_tx_status tx_status; + }; + /* RC_PID_EVENT_TYPE_RATE_CHANGE */ + /* RC_PID_EVENT_TYPE_TX_RATE */ + struct { + int index; + int rate; + }; + /* RC_PID_EVENT_TYPE_PF_SAMPLE */ + struct { + s32 pf_sample; + s32 prop_err; + s32 int_err; + s32 der_err; + }; +}; + +struct rc_pid_event { + /* The time when the event occured */ + unsigned long timestamp; + + /* Event ID number */ + unsigned int id; + + /* Type of event */ + enum rc_pid_event_type type; + + /* type specific data */ + union rc_pid_event_data data; +}; + +/* Size of the event ring buffer. */ +#define RC_PID_EVENT_RING_SIZE 32 + +struct rc_pid_event_buffer { + /* Counter that generates event IDs */ + unsigned int ev_count; + + /* Ring buffer of events */ + struct rc_pid_event ring[RC_PID_EVENT_RING_SIZE]; + + /* Index to the entry in events_buf to be reused */ + unsigned int next_entry; + + /* Lock that guards against concurrent access to this buffer struct */ + spinlock_t lock; + + /* Wait queue for poll/select and blocking I/O */ + wait_queue_head_t waitqueue; +}; + +struct rc_pid_events_file_info { + /* The event buffer we read */ + struct rc_pid_event_buffer *events; + + /* The entry we have should read next */ + unsigned int next_entry; +}; + +void rate_control_pid_event_tx_status(struct rc_pid_event_buffer *buf, + struct ieee80211_tx_status *stat); + +void rate_control_pid_event_rate_change(struct rc_pid_event_buffer *buf, + int index, int rate); + +void rate_control_pid_event_tx_rate(struct rc_pid_event_buffer *buf, + int index, int rate); + +void rate_control_pid_event_pf_sample(struct rc_pid_event_buffer *buf, + s32 pf_sample, s32 prop_err, + s32 int_err, s32 der_err); + +void rate_control_pid_add_sta_debugfs(void *priv, void *priv_sta, + struct dentry *dir); + +void rate_control_pid_remove_sta_debugfs(void *priv, void *priv_sta); + +struct rc_pid_sta_info { + unsigned long last_change; + unsigned long last_sample; + + u32 tx_num_failed; + u32 tx_num_xmit; + + /* Average failed frames percentage error (i.e. actual vs. target + * percentage), scaled by RC_PID_SMOOTHING. This value is computed + * using using an exponential weighted average technique: + * + * (RC_PID_SMOOTHING - 1) * err_avg_old + err + * err_avg = ------------------------------------------ + * RC_PID_SMOOTHING + * + * where err_avg is the new approximation, err_avg_old the previous one + * and err is the error w.r.t. to the current failed frames percentage + * sample. Note that the bigger RC_PID_SMOOTHING the more weight is + * given to the previous estimate, resulting in smoother behavior (i.e. + * corresponding to a longer integration window). + * + * For computation, we actually don't use the above formula, but this + * one: + * + * err_avg_scaled = err_avg_old_scaled - err_avg_old + err + * + * where: + * err_avg_scaled = err * RC_PID_SMOOTHING + * err_avg_old_scaled = err_avg_old * RC_PID_SMOOTHING + * + * This avoids floating point numbers and the per_failed_old value can + * easily be obtained by shifting per_failed_old_scaled right by + * RC_PID_SMOOTHING_SHIFT. + */ + s32 err_avg_sc; + + /* Last framed failes percentage sample. */ + u32 last_pf; + + /* Sharpening needed. */ + u8 sharp_cnt; + +#ifdef CONFIG_MAC80211_DEBUGFS + /* Event buffer */ + struct rc_pid_event_buffer events; + + /* Events debugfs file entry */ + struct dentry *events_entry; +#endif +}; + +/* Algorithm parameters. We keep them on a per-algorithm approach, so they can + * be tuned individually for each interface. + */ +struct rc_pid_rateinfo { + + /* Map sorted rates to rates in ieee80211_hw_mode. */ + int index; + + /* Map rates in ieee80211_hw_mode to sorted rates. */ + int rev_index; + + /* Did we do any measurement on this rate? */ + bool valid; + + /* Comparison with the lowest rate. */ + int diff; +}; + +struct rc_pid_info { + + /* The failed frames percentage target. */ + unsigned int target; + + /* Rate at which failed frames percentage is sampled in 0.001s. */ + unsigned int sampling_period; + + /* P, I and D coefficients. */ + int coeff_p; + int coeff_i; + int coeff_d; + + /* Exponential averaging shift. */ + unsigned int smoothing_shift; + + /* Sharpening shift and duration. */ + unsigned int sharpen_shift; + unsigned int sharpen_duration; + + /* Normalization offset. */ + unsigned int norm_offset; + + /* Fast starst parameter. */ + unsigned int fast_start; + + /* Rates information. */ + struct rc_pid_rateinfo *rinfo; + + /* Index of the last used rate. */ + int oldrate; +}; + +#endif /* RC80211_PID_H */ diff --git a/net/mac80211/rc80211_pid.c b/net/mac80211/rc80211_pid_algo.c index 7f8cf27ad2f..3fac3a5d7e0 100644 --- a/net/mac80211/rc80211_pid.c +++ b/net/mac80211/rc80211_pid_algo.c @@ -16,6 +16,8 @@ #include <net/mac80211.h> #include "ieee80211_rate.h" +#include "rc80211_pid.h" + /* This is an implementation of a TX rate control algorithm that uses a PID * controller. Given a target failed frames rate, the controller decides about @@ -61,121 +63,6 @@ * RC_PID_ARITH_SHIFT. */ -/* Sampling period for measuring percentage of failed frames. */ -#define RC_PID_INTERVAL (HZ / 8) - -/* Exponential averaging smoothness (used for I part of PID controller) */ -#define RC_PID_SMOOTHING_SHIFT 3 -#define RC_PID_SMOOTHING (1 << RC_PID_SMOOTHING_SHIFT) - -/* Sharpening factor (used for D part of PID controller) */ -#define RC_PID_SHARPENING_FACTOR 0 -#define RC_PID_SHARPENING_DURATION 0 - -/* Fixed point arithmetic shifting amount. */ -#define RC_PID_ARITH_SHIFT 8 - -/* Fixed point arithmetic factor. */ -#define RC_PID_ARITH_FACTOR (1 << RC_PID_ARITH_SHIFT) - -/* Proportional PID component coefficient. */ -#define RC_PID_COEFF_P 15 -/* Integral PID component coefficient. */ -#define RC_PID_COEFF_I 9 -/* Derivative PID component coefficient. */ -#define RC_PID_COEFF_D 15 - -/* Target failed frames rate for the PID controller. NB: This effectively gives - * maximum failed frames percentage we're willing to accept. If the wireless - * link quality is good, the controller will fail to adjust failed frames - * percentage to the target. This is intentional. - */ -#define RC_PID_TARGET_PF (11 << RC_PID_ARITH_SHIFT) - -/* Rate behaviour normalization quantity over time. */ -#define RC_PID_NORM_OFFSET 3 - -/* Push high rates right after loading. */ -#define RC_PID_FAST_START 0 - -/* Arithmetic right shift for positive and negative values for ISO C. */ -#define RC_PID_DO_ARITH_RIGHT_SHIFT(x, y) \ - (x) < 0 ? -((-(x)) >> (y)) : (x) >> (y) - -struct rc_pid_sta_info { - unsigned long last_change; - unsigned long last_sample; - - u32 tx_num_failed; - u32 tx_num_xmit; - - /* Average failed frames percentage error (i.e. actual vs. target - * percentage), scaled by RC_PID_SMOOTHING. This value is computed - * using using an exponential weighted average technique: - * - * (RC_PID_SMOOTHING - 1) * err_avg_old + err - * err_avg = ------------------------------------------ - * RC_PID_SMOOTHING - * - * where err_avg is the new approximation, err_avg_old the previous one - * and err is the error w.r.t. to the current failed frames percentage - * sample. Note that the bigger RC_PID_SMOOTHING the more weight is - * given to the previous estimate, resulting in smoother behavior (i.e. - * corresponding to a longer integration window). - * - * For computation, we actually don't use the above formula, but this - * one: - * - * err_avg_scaled = err_avg_old_scaled - err_avg_old + err - * - * where: - * err_avg_scaled = err * RC_PID_SMOOTHING - * err_avg_old_scaled = err_avg_old * RC_PID_SMOOTHING - * - * This avoids floating point numbers and the per_failed_old value can - * easily be obtained by shifting per_failed_old_scaled right by - * RC_PID_SMOOTHING_SHIFT. - */ - s32 err_avg_sc; - - /* Last framed failes percentage sample. */ - u32 last_pf; - - /* Sharpening needed. */ - u8 sharp_cnt; -}; - -/* Algorithm parameters. We keep them on a per-algorithm approach, so they can - * be tuned individually for each interface. - */ -struct rc_pid_rateinfo { - - /* Map sorted rates to rates in ieee80211_hw_mode. */ - int index; - - /* Map rates in ieee80211_hw_mode to sorted rates. */ - int rev_index; - - /* Comparison with the lowest rate. */ - int diff; -}; - -struct rc_pid_info { - - /* The failed frames percentage target. */ - u32 target; - - /* P, I and D coefficients. */ - s32 coeff_p; - s32 coeff_i; - s32 coeff_d; - - /* Rates information. */ - struct rc_pid_rateinfo *rinfo; - - /* Index of the last used rate. */ - int oldrate; -}; /* Shift the adjustment so that we won't switch to a lower rate if it exhibited * a worse failed frames behaviour and we'll choose the highest rate whose @@ -243,6 +130,12 @@ static void rate_control_pid_adjust_rate(struct ieee80211_local *local, newidx += back; } + +#ifdef CONFIG_MAC80211_DEBUGFS + rate_control_pid_event_rate_change( + &((struct rc_pid_sta_info *)sta->rate_ctrl_priv)->events, + newidx, mode->rates[newidx].rate); +#endif } /* Normalize the failed frames per-rate differences. */ @@ -324,6 +217,11 @@ static void rate_control_pid_sample(struct rc_pid_info *pinfo, if (spinfo->sharp_cnt) spinfo->sharp_cnt--; +#ifdef CONFIG_MAC80211_DEBUGFS + rate_control_pid_event_pf_sample(&spinfo->events, pf, err_prop, err_int, + err_der); +#endif + /* Compute the controller output. */ adj = (err_prop * pinfo->coeff_p + err_int * pinfo->coeff_i + err_der * pinfo->coeff_d); @@ -357,6 +255,10 @@ static void rate_control_pid_tx_status(void *priv, struct net_device *dev, spinfo = sta->rate_ctrl_priv; spinfo->tx_num_xmit++; +#ifdef CONFIG_MAC80211_DEBUGFS + rate_control_pid_event_tx_status(&spinfo->events, status); +#endif + /* We count frames that totally failed to be transmitted as two bad * frames, those that made it out but had some retries as one good and * one bad frame. */ @@ -415,6 +317,12 @@ static void rate_control_pid_get_rate(void *priv, struct net_device *dev, sta_info_put(sta); sel->rate = &mode->rates[rateidx]; + +#ifdef CONFIG_MAC80211_DEBUGFS + rate_control_pid_event_tx_rate( + &((struct rc_pid_sta_info *) sta->rate_ctrl_priv)->events, + rateidx, mode->rates[rateidx].rate); +#endif } static void rate_control_pid_rate_init(void *priv, void *priv_sta, @@ -502,6 +410,13 @@ static void *rate_control_pid_alloc_sta(void *priv, gfp_t gfp) struct rc_pid_sta_info *spinfo; spinfo = kzalloc(sizeof(*spinfo), gfp); + if (spinfo == NULL) + return NULL; + +#ifdef CONFIG_MAC80211_DEBUGFS + spin_lock_init(&spinfo->events.lock); + init_waitqueue_head(&spinfo->events.waitqueue); +#endif return spinfo; } @@ -522,4 +437,8 @@ struct rate_control_ops mac80211_rcpid = { .free = rate_control_pid_free, .alloc_sta = rate_control_pid_alloc_sta, .free_sta = rate_control_pid_free_sta, +#ifdef CONFIG_MAC80211_DEBUGFS + .add_sta_debugfs = rate_control_pid_add_sta_debugfs, + .remove_sta_debugfs = rate_control_pid_remove_sta_debugfs, +#endif }; diff --git a/net/mac80211/rc80211_pid_debugfs.c b/net/mac80211/rc80211_pid_debugfs.c new file mode 100644 index 00000000000..91818e4ff00 --- /dev/null +++ b/net/mac80211/rc80211_pid_debugfs.c @@ -0,0 +1,223 @@ +/* + * Copyright 2007, Mattias Nissler <mattias.nissler@gmx.de> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/spinlock.h> +#include <linux/poll.h> +#include <linux/netdevice.h> +#include <linux/types.h> +#include <linux/skbuff.h> + +#include <net/mac80211.h> +#include "ieee80211_rate.h" + +#include "rc80211_pid.h" + +static void rate_control_pid_event(struct rc_pid_event_buffer *buf, + enum rc_pid_event_type type, + union rc_pid_event_data *data) +{ + struct rc_pid_event *ev; + unsigned long status; + + spin_lock_irqsave(&buf->lock, status); + ev = &(buf->ring[buf->next_entry]); + buf->next_entry = (buf->next_entry + 1) % RC_PID_EVENT_RING_SIZE; + + ev->timestamp = jiffies; + ev->id = buf->ev_count++; + ev->type = type; + ev->data = *data; + + spin_unlock_irqrestore(&buf->lock, status); + + wake_up_all(&buf->waitqueue); +} + +void rate_control_pid_event_tx_status(struct rc_pid_event_buffer *buf, + struct ieee80211_tx_status *stat) +{ + union rc_pid_event_data evd; + + memcpy(&evd.tx_status, stat, sizeof(struct ieee80211_tx_status)); + rate_control_pid_event(buf, RC_PID_EVENT_TYPE_TX_STATUS, &evd); +} + +void rate_control_pid_event_rate_change(struct rc_pid_event_buffer *buf, + int index, int rate) +{ + union rc_pid_event_data evd; + + evd.index = index; + evd.rate = rate; + rate_control_pid_event(buf, RC_PID_EVENT_TYPE_RATE_CHANGE, &evd); +} + +void rate_control_pid_event_tx_rate(struct rc_pid_event_buffer *buf, + int index, int rate) +{ + union rc_pid_event_data evd; + + evd.index = index; + evd.rate = rate; + rate_control_pid_event(buf, RC_PID_EVENT_TYPE_TX_RATE, &evd); +} + +void rate_control_pid_event_pf_sample(struct rc_pid_event_buffer *buf, + s32 pf_sample, s32 prop_err, + s32 int_err, s32 der_err) +{ + union rc_pid_event_data evd; + + evd.pf_sample = pf_sample; + evd.prop_err = prop_err; + evd.int_err = int_err; + evd.der_err = der_err; + rate_control_pid_event(buf, RC_PID_EVENT_TYPE_PF_SAMPLE, &evd); +} + +static int rate_control_pid_events_open(struct inode *inode, struct file *file) +{ + struct rc_pid_sta_info *sinfo = inode->i_private; + struct rc_pid_event_buffer *events = &sinfo->events; + struct rc_pid_events_file_info *file_info; + unsigned int status; + + /* Allocate a state struct */ + file_info = kmalloc(sizeof(*file_info), GFP_KERNEL); + if (file_info == NULL) + return -ENOMEM; + + spin_lock_irqsave(&events->lock, status); + + file_info->next_entry = events->next_entry; + file_info->events = events; + + spin_unlock_irqrestore(&events->lock, status); + + file->private_data = file_info; + + return 0; +} + +static int rate_control_pid_events_release(struct inode *inode, + struct file *file) +{ + struct rc_pid_events_file_info *file_info = file->private_data; + + kfree(file_info); + + return 0; +} + +static unsigned int rate_control_pid_events_poll(struct file *file, + poll_table *wait) +{ + struct rc_pid_events_file_info *file_info = file->private_data; + + poll_wait(file, &file_info->events->waitqueue, wait); + + return POLLIN | POLLRDNORM; +} + +#define RC_PID_PRINT_BUF_SIZE 64 + +static ssize_t rate_control_pid_events_read(struct file *file, char __user *buf, + size_t length, loff_t *offset) +{ + struct rc_pid_events_file_info *file_info = file->private_data; + struct rc_pid_event_buffer *events = file_info->events; + struct rc_pid_event *ev; + char pb[RC_PID_PRINT_BUF_SIZE]; + int ret; + int p; + unsigned int status; + + /* Check if there is something to read. */ + if (events->next_entry == file_info->next_entry) { + if (file->f_flags & O_NONBLOCK) + return -EAGAIN; + + /* Wait */ + ret = wait_event_interruptible(events->waitqueue, + events->next_entry != file_info->next_entry); + + if (ret) + return ret; + } + + /* Write out one event per call. I don't care whether it's a little + * inefficient, this is debugging code anyway. */ + spin_lock_irqsave(&events->lock, status); + + /* Get an event */ + ev = &(events->ring[file_info->next_entry]); + file_info->next_entry = (file_info->next_entry + 1) % + RC_PID_EVENT_RING_SIZE; + + /* Print information about the event. Note that userpace needs to + * provide large enough buffers. */ + length = length < RC_PID_PRINT_BUF_SIZE ? + length : RC_PID_PRINT_BUF_SIZE; + p = snprintf(pb, length, "%u %lu ", ev->id, ev->timestamp); + switch (ev->type) { + case RC_PID_EVENT_TYPE_TX_STATUS: + p += snprintf(pb + p, length - p, "tx_status %u %u", + ev->data.tx_status.excessive_retries, + ev->data.tx_status.retry_count); + break; + case RC_PID_EVENT_TYPE_RATE_CHANGE: + p += snprintf(pb + p, length - p, "rate_change %d %d", + ev->data.index, ev->data.rate); + break; + case RC_PID_EVENT_TYPE_TX_RATE: + p += snprintf(pb + p, length - p, "tx_rate %d %d", + ev->data.index, ev->data.rate); + break; + case RC_PID_EVENT_TYPE_PF_SAMPLE: + p += snprintf(pb + p, length - p, + "pf_sample %d %d %d %d", + ev->data.pf_sample, ev->data.prop_err, + ev->data.int_err, ev->data.der_err); + break; + } + p += snprintf(pb + p, length - p, "\n"); + + spin_unlock_irqrestore(&events->lock, status); + + if (copy_to_user(buf, pb, p)) + return -EFAULT; + + return p; +} + +#undef RC_PID_PRINT_BUF_SIZE + +struct file_operations rc_pid_fop_events = { + .owner = THIS_MODULE, + .read = rate_control_pid_events_read, + .poll = rate_control_pid_events_poll, + .open = rate_control_pid_events_open, + .release = rate_control_pid_events_release, +}; + +void rate_control_pid_add_sta_debugfs(void *priv, void *priv_sta, + struct dentry *dir) +{ + struct rc_pid_sta_info *spinfo = priv_sta; + + spinfo->events_entry = debugfs_create_file("rc_pid_events", S_IRUGO, + dir, spinfo, + &rc_pid_fop_events); +} + +void rate_control_pid_remove_sta_debugfs(void *priv, void *priv_sta) +{ + struct rc_pid_sta_info *spinfo = priv_sta; + + debugfs_remove(spinfo->events_entry); +} |