drivers/staging/android/sync_debug.c

   1 /*
   2  * drivers/base/sync.c
   3  *
   4  * Copyright (C) 2012 Google, Inc.
   5  *
   6  * This software is licensed under the terms of the GNU General Public
   7  * License version 2, as published by the Free Software Foundation, and
   8  * may be copied, distributed, and modified under those terms.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  */
  16
  17 #include <linux/debugfs.h>
  18 #include <linux/export.h>
  19 #include <linux/file.h>
  20 #include <linux/fs.h>
  21 #include <linux/kernel.h>
  22 #include <linux/poll.h>
  23 #include <linux/sched.h>
  24 #include <linux/seq_file.h>
  25 #include <linux/slab.h>
  26 #include <linux/uaccess.h>
  27 #include <linux/anon_inodes.h>
  28 #include <linux/time64.h>
  29 #include <linux/sync_file.h>
  30 #include <linux/types.h>
  31 #include <linux/kconfig.h>
  32
  33 #include "uapi/sw_sync.h"
  34 #include "sync.h"
  35
  36 #ifdef CONFIG_DEBUG_FS
  37
  38 static struct dentry *dbgfs;
  39
  40 static LIST_HEAD(sync_timeline_list_head);
  41 static DEFINE_SPINLOCK(sync_timeline_list_lock);
  42 static LIST_HEAD(sync_file_list_head);
  43 static DEFINE_SPINLOCK(sync_file_list_lock);
  44
  45 void sync_timeline_debug_add(struct sync_timeline *obj)
  46 {
  47         unsigned long flags;
  48
  49         spin_lock_irqsave(&sync_timeline_list_lock, flags);
  50         list_add_tail(&obj->sync_timeline_list, &sync_timeline_list_head);
  51         spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
  52 }
  53
  54 void sync_timeline_debug_remove(struct sync_timeline *obj)
  55 {
  56         unsigned long flags;
  57
  58         spin_lock_irqsave(&sync_timeline_list_lock, flags);
  59         list_del(&obj->sync_timeline_list);
  60         spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
  61 }
  62
  63 void sync_file_debug_add(struct sync_file *sync_file)
  64 {
  65         unsigned long flags;
  66
  67         spin_lock_irqsave(&sync_file_list_lock, flags);
  68         list_add_tail(&sync_file->sync_file_list, &sync_file_list_head);
  69         spin_unlock_irqrestore(&sync_file_list_lock, flags);
  70 }
  71
  72 void sync_file_debug_remove(struct sync_file *sync_file)
  73 {
  74         unsigned long flags;
  75
  76         spin_lock_irqsave(&sync_file_list_lock, flags);
  77         list_del(&sync_file->sync_file_list);
  78         spin_unlock_irqrestore(&sync_file_list_lock, flags);
  79 }
  80
  81 static const char *sync_status_str(int status)
  82 {
  83         if (status == 0)
  84                 return "signaled";
  85
  86         if (status > 0)
  87                 return "active";
  88
  89         return "error";
  90 }
  91
  92 static void sync_print_fence(struct seq_file *s, struct fence *fence, bool show)
  93 {
  94         int status = 1;
  95         struct sync_timeline *parent = fence_parent(fence);
  96
  97         if (fence_is_signaled_locked(fence))
  98                 status = fence->status;
  99
 100         seq_printf(s, "  %s%sfence %s",
 101                    show ? parent->name : "",
 102                    show ? "_" : "",
 103                    sync_status_str(status));
 104
 105         if (status <= 0) {
 106                 struct timespec64 ts64 =
 107                         ktime_to_timespec64(fence->timestamp);
 108
 109                 seq_printf(s, "@%lld.%09ld", (s64)ts64.tv_sec, ts64.tv_nsec);
 110         }
 111
 112         if (fence->ops->timeline_value_str &&
 113                 fence->ops->fence_value_str) {
 114                 char value[64];
 115                 bool success;
 116
 117                 fence->ops->fence_value_str(fence, value, sizeof(value));
 118                 success = strlen(value);
 119
 120                 if (success) {
 121                         seq_printf(s, ": %s", value);
 122
 123                         fence->ops->timeline_value_str(fence, value,
 124                                                        sizeof(value));
 125
 126                         if (strlen(value))
 127                                 seq_printf(s, " / %s", value);
 128                 }
 129         }
 130
 131         seq_puts(s, "\n");
 132 }
 133
 134 static void sync_print_obj(struct seq_file *s, struct sync_timeline *obj)
 135 {
 136         struct list_head *pos;
 137         unsigned long flags;
 138
 139         seq_printf(s, "%s %s: %d\n", obj->name, obj->drv_name, obj->value);
 140
 141         spin_lock_irqsave(&obj->child_list_lock, flags);
 142         list_for_each(pos, &obj->child_list_head) {
 143                 struct sync_pt *pt =
 144                         container_of(pos, struct sync_pt, child_list);
 145                 sync_print_fence(s, &pt->base, false);
 146         }
 147         spin_unlock_irqrestore(&obj->child_list_lock, flags);
 148 }
 149
 150 static void sync_print_sync_file(struct seq_file *s,
 151                                   struct sync_file *sync_file)
 152 {
 153         int i;
 154
 155         seq_printf(s, "[%p] %s: %s\n", sync_file, sync_file->name,
 156                    sync_status_str(atomic_read(&sync_file->status)));
 157
 158         for (i = 0; i < sync_file->num_fences; ++i)
 159                 sync_print_fence(s, sync_file->cbs[i].fence, true);
 160 }
 161
 162 static int sync_debugfs_show(struct seq_file *s, void *unused)
 163 {
 164         unsigned long flags;
 165         struct list_head *pos;
 166
 167         seq_puts(s, "objs:\n--------------\n");
 168
 169         spin_lock_irqsave(&sync_timeline_list_lock, flags);
 170         list_for_each(pos, &sync_timeline_list_head) {
 171                 struct sync_timeline *obj =
 172                         container_of(pos, struct sync_timeline,
 173                                      sync_timeline_list);
 174
 175                 sync_print_obj(s, obj);
 176                 seq_puts(s, "\n");
 177         }
 178         spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
 179
 180         seq_puts(s, "fences:\n--------------\n");
 181
 182         spin_lock_irqsave(&sync_file_list_lock, flags);
 183         list_for_each(pos, &sync_file_list_head) {
 184                 struct sync_file *sync_file =
 185                         container_of(pos, struct sync_file, sync_file_list);
 186
 187                 sync_print_sync_file(s, sync_file);
 188                 seq_puts(s, "\n");
 189         }
 190         spin_unlock_irqrestore(&sync_file_list_lock, flags);
 191         return 0;
 192 }
 193
 194 static int sync_info_debugfs_open(struct inode *inode, struct file *file)
 195 {
 196         return single_open(file, sync_debugfs_show, inode->i_private);
 197 }
 198
 199 static const struct file_operations sync_info_debugfs_fops = {
 200         .open           = sync_info_debugfs_open,
 201         .read           = seq_read,
 202         .llseek         = seq_lseek,
 203         .release        = single_release,
 204 };
 205
 206 #if IS_ENABLED(CONFIG_SW_SYNC)
 207 /*
 208  * *WARNING*
 209  *
 210  * improper use of this can result in deadlocking kernel drivers from userspace.
 211  */
 212
 213 /* opening sw_sync create a new sync obj */
 214 static int sw_sync_debugfs_open(struct inode *inode, struct file *file)
 215 {
 216         struct sync_timeline *obj;
 217         char task_comm[TASK_COMM_LEN];
 218
 219         get_task_comm(task_comm, current);
 220
 221         obj = sync_timeline_create("sw_sync", task_comm);
 222         if (!obj)
 223                 return -ENOMEM;
 224
 225         file->private_data = obj;
 226
 227         return 0;
 228 }
 229
 230 static int sw_sync_debugfs_release(struct inode *inode, struct file *file)
 231 {
 232         struct sync_timeline *obj = file->private_data;
 233
 234         sync_timeline_destroy(obj);
 235         return 0;
 236 }
 237
 238 static long sw_sync_ioctl_create_fence(struct sync_timeline *obj,
 239                                        unsigned long arg)
 240 {
 241         int fd = get_unused_fd_flags(O_CLOEXEC);
 242         int err;
 243         struct sync_pt *pt;
 244         struct sync_file *sync_file;
 245         struct sw_sync_create_fence_data data;
 246
 247         if (fd < 0)
 248                 return fd;
 249
 250         if (copy_from_user(&data, (void __user *)arg, sizeof(data))) {
 251                 err = -EFAULT;
 252                 goto err;
 253         }
 254
 255         pt = sync_pt_create(obj, sizeof(*pt), data.value);
 256         if (!pt) {
 257                 err = -ENOMEM;
 258                 goto err;
 259         }
 260
 261         sync_file = sync_file_create(&pt->base);
 262         if (!sync_file) {
 263                 fence_put(&pt->base);
 264                 err = -ENOMEM;
 265                 goto err;
 266         }
 267
 268         data.fence = fd;
 269         if (copy_to_user((void __user *)arg, &data, sizeof(data))) {
 270                 fput(sync_file->file);
 271                 err = -EFAULT;
 272                 goto err;
 273         }
 274
 275         fd_install(fd, sync_file->file);
 276
 277         return 0;
 278
 279 err:
 280         put_unused_fd(fd);
 281         return err;
 282 }
 283
 284 static long sw_sync_ioctl_inc(struct sync_timeline *obj, unsigned long arg)
 285 {
 286         u32 value;
 287
 288         if (copy_from_user(&value, (void __user *)arg, sizeof(value)))
 289                 return -EFAULT;
 290
 291         sync_timeline_signal(obj, value);
 292
 293         return 0;
 294 }
 295
 296 static long sw_sync_ioctl(struct file *file, unsigned int cmd,
 297                           unsigned long arg)
 298 {
 299         struct sync_timeline *obj = file->private_data;
 300
 301         switch (cmd) {
 302         case SW_SYNC_IOC_CREATE_FENCE:
 303                 return sw_sync_ioctl_create_fence(obj, arg);
 304
 305         case SW_SYNC_IOC_INC:
 306                 return sw_sync_ioctl_inc(obj, arg);
 307
 308         default:
 309                 return -ENOTTY;
 310         }
 311 }
 312
 313 static const struct file_operations sw_sync_debugfs_fops = {
 314         .open           = sw_sync_debugfs_open,
 315         .release        = sw_sync_debugfs_release,
 316         .unlocked_ioctl = sw_sync_ioctl,
 317         .compat_ioctl = sw_sync_ioctl,
 318 };
 319 #endif
 320
 321 static __init int sync_debugfs_init(void)
 322 {
 323         dbgfs = debugfs_create_dir("sync", NULL);
 324
 325         debugfs_create_file("info", 0444, dbgfs, NULL, &sync_info_debugfs_fops);
 326
 327 #if IS_ENABLED(CONFIG_SW_SYNC)
 328         debugfs_create_file("sw_sync", 0644, dbgfs, NULL,
 329                             &sw_sync_debugfs_fops);
 330 #endif
 331
 332         return 0;
 333 }
 334 late_initcall(sync_debugfs_init);
 335
 336 #define DUMP_CHUNK 256
 337 static char sync_dump_buf[64 * 1024];
 338 void sync_dump(void)
 339 {
 340         struct seq_file s = {
 341                 .buf = sync_dump_buf,
 342                 .size = sizeof(sync_dump_buf) - 1,
 343         };
 344         int i;
 345
 346         sync_debugfs_show(&s, NULL);
 347
 348         for (i = 0; i < s.count; i += DUMP_CHUNK) {
 349                 if ((s.count - i) > DUMP_CHUNK) {
 350                         char c = s.buf[i + DUMP_CHUNK];
 351
 352                         s.buf[i + DUMP_CHUNK] = 0;
 353                         pr_cont("%s", s.buf + i);
 354                         s.buf[i + DUMP_CHUNK] = c;
 355                 } else {
 356                         s.buf[s.count] = 0;
 357                         pr_cont("%s", s.buf + i);
 358                 }
 359         }
 360 }
 361
 362 #endif