net/mac80211/rc80211_pid_debugfs.c

   1 /*
   2  * Copyright 2007, Mattias Nissler <mattias.nissler@gmx.de>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  */
   8
   9 #include <linux/sched.h>
  10 #include <linux/spinlock.h>
  11 #include <linux/poll.h>
  12 #include <linux/netdevice.h>
  13 #include <linux/types.h>
  14 #include <linux/skbuff.h>
  15 #include <linux/slab.h>
  16
  17 #include <net/mac80211.h>
  18 #include "rate.h"
  19
  20 #include "rc80211_pid.h"
  21
  22 static void rate_control_pid_event(struct rc_pid_event_buffer *buf,
  23                                    enum rc_pid_event_type type,
  24                                    union rc_pid_event_data *data)
  25 {
  26         struct rc_pid_event *ev;
  27         unsigned long status;
  28
  29         spin_lock_irqsave(&buf->lock, status);
  30         ev = &(buf->ring[buf->next_entry]);
  31         buf->next_entry = (buf->next_entry + 1) % RC_PID_EVENT_RING_SIZE;
  32
  33         ev->timestamp = jiffies;
  34         ev->id = buf->ev_count++;
  35         ev->type = type;
  36         ev->data = *data;
  37
  38         spin_unlock_irqrestore(&buf->lock, status);
  39
  40         wake_up_all(&buf->waitqueue);
  41 }
  42
  43 void rate_control_pid_event_tx_status(struct rc_pid_event_buffer *buf,
  44                                       struct ieee80211_tx_info *stat)
  45 {
  46         union rc_pid_event_data evd;
  47
  48         evd.flags = stat->flags;
  49         memcpy(&evd.tx_status, stat, sizeof(struct ieee80211_tx_info));
  50         rate_control_pid_event(buf, RC_PID_EVENT_TYPE_TX_STATUS, &evd);
  51 }
  52
  53 void rate_control_pid_event_rate_change(struct rc_pid_event_buffer *buf,
  54                                                int index, int rate)
  55 {
  56         union rc_pid_event_data evd;
  57
  58         evd.index = index;
  59         evd.rate = rate;
  60         rate_control_pid_event(buf, RC_PID_EVENT_TYPE_RATE_CHANGE, &evd);
  61 }
  62
  63 void rate_control_pid_event_tx_rate(struct rc_pid_event_buffer *buf,
  64                                            int index, int rate)
  65 {
  66         union rc_pid_event_data evd;
  67
  68         evd.index = index;
  69         evd.rate = rate;
  70         rate_control_pid_event(buf, RC_PID_EVENT_TYPE_TX_RATE, &evd);
  71 }
  72
  73 void rate_control_pid_event_pf_sample(struct rc_pid_event_buffer *buf,
  74                                              s32 pf_sample, s32 prop_err,
  75                                              s32 int_err, s32 der_err)
  76 {
  77         union rc_pid_event_data evd;
  78
  79         evd.pf_sample = pf_sample;
  80         evd.prop_err = prop_err;
  81         evd.int_err = int_err;
  82         evd.der_err = der_err;
  83         rate_control_pid_event(buf, RC_PID_EVENT_TYPE_PF_SAMPLE, &evd);
  84 }
  85
  86 static int rate_control_pid_events_open(struct inode *inode, struct file *file)
  87 {
  88         struct rc_pid_sta_info *sinfo = inode->i_private;
  89         struct rc_pid_event_buffer *events = &sinfo->events;
  90         struct rc_pid_events_file_info *file_info;
  91         unsigned long status;
  92
  93         /* Allocate a state struct */
  94         file_info = kmalloc(sizeof(*file_info), GFP_KERNEL);
  95         if (file_info == NULL)
  96                 return -ENOMEM;
  97
  98         spin_lock_irqsave(&events->lock, status);
  99
 100         file_info->next_entry = events->next_entry;
 101         file_info->events = events;
 102
 103         spin_unlock_irqrestore(&events->lock, status);
 104
 105         file->private_data = file_info;
 106
 107         return 0;
 108 }
 109
 110 static int rate_control_pid_events_release(struct inode *inode,
 111                                            struct file *file)
 112 {
 113         struct rc_pid_events_file_info *file_info = file->private_data;
 114
 115         kfree(file_info);
 116
 117         return 0;
 118 }
 119
 120 static unsigned int rate_control_pid_events_poll(struct file *file,
 121                                                  poll_table *wait)
 122 {
 123         struct rc_pid_events_file_info *file_info = file->private_data;
 124
 125         poll_wait(file, &file_info->events->waitqueue, wait);
 126
 127         return POLLIN | POLLRDNORM;
 128 }
 129
 130 #define RC_PID_PRINT_BUF_SIZE 64
 131
 132 static ssize_t rate_control_pid_events_read(struct file *file, char __user *buf,
 133                                             size_t length, loff_t *offset)
 134 {
 135         struct rc_pid_events_file_info *file_info = file->private_data;
 136         struct rc_pid_event_buffer *events = file_info->events;
 137         struct rc_pid_event *ev;
 138         char pb[RC_PID_PRINT_BUF_SIZE];
 139         int ret;
 140         int p;
 141         unsigned long status;
 142
 143         /* Check if there is something to read. */
 144         if (events->next_entry == file_info->next_entry) {
 145                 if (file->f_flags & O_NONBLOCK)
 146                         return -EAGAIN;
 147
 148                 /* Wait */
 149                 ret = wait_event_interruptible(events->waitqueue,
 150                                 events->next_entry != file_info->next_entry);
 151
 152                 if (ret)
 153                         return ret;
 154         }
 155
 156         /* Write out one event per call. I don't care whether it's a little
 157          * inefficient, this is debugging code anyway. */
 158         spin_lock_irqsave(&events->lock, status);
 159
 160         /* Get an event */
 161         ev = &(events->ring[file_info->next_entry]);
 162         file_info->next_entry = (file_info->next_entry + 1) %
 163                                 RC_PID_EVENT_RING_SIZE;
 164
 165         /* Print information about the event. Note that userspace needs to
 166          * provide large enough buffers. */
 167         length = length < RC_PID_PRINT_BUF_SIZE ?
 168                  length : RC_PID_PRINT_BUF_SIZE;
 169         p = snprintf(pb, length, "%u %lu ", ev->id, ev->timestamp);
 170         switch (ev->type) {
 171         case RC_PID_EVENT_TYPE_TX_STATUS:
 172                 p += snprintf(pb + p, length - p, "tx_status %u %u",
 173                               !(ev->data.flags & IEEE80211_TX_STAT_ACK),
 174                               ev->data.tx_status.status.rates[0].idx);
 175                 break;
 176         case RC_PID_EVENT_TYPE_RATE_CHANGE:
 177                 p += snprintf(pb + p, length - p, "rate_change %d %d",
 178                               ev->data.index, ev->data.rate);
 179                 break;
 180         case RC_PID_EVENT_TYPE_TX_RATE:
 181                 p += snprintf(pb + p, length - p, "tx_rate %d %d",
 182                               ev->data.index, ev->data.rate);
 183                 break;
 184         case RC_PID_EVENT_TYPE_PF_SAMPLE:
 185                 p += snprintf(pb + p, length - p,
 186                               "pf_sample %d %d %d %d",
 187                               ev->data.pf_sample, ev->data.prop_err,
 188                               ev->data.int_err, ev->data.der_err);
 189                 break;
 190         }
 191         p += snprintf(pb + p, length - p, "\n");
 192
 193         spin_unlock_irqrestore(&events->lock, status);
 194
 195         if (copy_to_user(buf, pb, p))
 196                 return -EFAULT;
 197
 198         return p;
 199 }
 200
 201 #undef RC_PID_PRINT_BUF_SIZE
 202
 203 static const struct file_operations rc_pid_fop_events = {
 204         .owner = THIS_MODULE,
 205         .read = rate_control_pid_events_read,
 206         .poll = rate_control_pid_events_poll,
 207         .open = rate_control_pid_events_open,
 208         .release = rate_control_pid_events_release,
 209         .llseek = noop_llseek,
 210 };
 211
 212 void rate_control_pid_add_sta_debugfs(void *priv, void *priv_sta,
 213                                              struct dentry *dir)
 214 {
 215         struct rc_pid_sta_info *spinfo = priv_sta;
 216
 217         spinfo->events_entry = debugfs_create_file("rc_pid_events", S_IRUGO,
 218                                                    dir, spinfo,
 219                                                    &rc_pid_fop_events);
 220 }
 221
 222 void rate_control_pid_remove_sta_debugfs(void *priv, void *priv_sta)
 223 {
 224         struct rc_pid_sta_info *spinfo = priv_sta;
 225
 226         debugfs_remove(spinfo->events_entry);
 227 }