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