| 1 | /* |
| 2 | * LTT ascii binary buffer to ascii converter. |
| 3 | * |
| 4 | * Copyright 2008 - 2009 Lai Jiangshan (laijs@cn.fujitsu.com) |
| 5 | * Copyright 2009 - Mathieu Desnoyers mathieu.desnoyers@polymtl.ca |
| 6 | * |
| 7 | * Dual LGPL v2.1/GPL v2 license. |
| 8 | */ |
| 9 | |
| 10 | /* |
| 11 | * TODO |
| 12 | * |
| 13 | * Move to new switch behavior: Wait for data for the duration of the |
| 14 | * timer interval + safety, if none is coming, consider that no activity occured |
| 15 | * in the buffer. |
| 16 | * |
| 17 | * Fix case when having a text file open and destroying trace. |
| 18 | * |
| 19 | * - Automate periodical switch: |
| 20 | * |
| 21 | * The debugfs file "switch_timer" receives a timer period as parameter |
| 22 | * (e.g. echo 100 > switch_timer) to activate the timer per channel. This can |
| 23 | * also be accessed through the internal API _before the trace session starts_. |
| 24 | * This timer will insure that we periodically have subbuffers to read, and |
| 25 | * therefore that the merge-sort does not wait endlessly for a subbuffer. |
| 26 | * |
| 27 | * - If a channel is switched and read without data, make sure it is still |
| 28 | * considered afterward (not removed from the queue). |
| 29 | * |
| 30 | * - Create a ascii/tracename/ALL file to merge-sort all active channels. |
| 31 | * - Create a ascii/tracename/README file to contain the text output legend. |
| 32 | * - Remove leading zeroes from timestamps. |
| 33 | * - Enhance pretty-printing to make sure all types used for addesses output in |
| 34 | * the form 0xAB00000000 (not decimal). This is true for %p and 0x%...X. |
| 35 | * - Hotplug support |
| 36 | */ |
| 37 | |
| 38 | |
| 39 | |
| 40 | |
| 41 | #include <linux/module.h> |
| 42 | #include <linux/seq_file.h> |
| 43 | #include <linux/debugfs.h> |
| 44 | #include <linux/module.h> |
| 45 | #include <linux/string.h> |
| 46 | #include <linux/delay.h> |
| 47 | #include <linux/slab.h> |
| 48 | #include <linux/cpu.h> |
| 49 | #include <linux/fs.h> |
| 50 | |
| 51 | #include "ltt-tracer.h" |
| 52 | #include "ltt-relay.h" |
| 53 | #include "ltt-relay-lockless.h" |
| 54 | |
| 55 | #if 0 |
| 56 | #define DEBUGP printk |
| 57 | #else |
| 58 | #define DEBUGP(fmt , a...) |
| 59 | #endif |
| 60 | |
| 61 | struct dentry *ltt_ascii_dir_dentry; |
| 62 | EXPORT_SYMBOL_GPL(ltt_ascii_dir_dentry); |
| 63 | |
| 64 | struct ltt_relay_iter; |
| 65 | |
| 66 | struct ltt_relay_cpu_iter { |
| 67 | /* cpu buffer information */ |
| 68 | struct ltt_chanbuf *buf; |
| 69 | struct ltt_relay_iter *iter; |
| 70 | int sb_ref; /* holding a reference to a subbuffer */ |
| 71 | long read_sb_offset; /* offset of the subbuffer read */ |
| 72 | |
| 73 | /* current event information */ |
| 74 | struct ltt_subbuffer_header *header; |
| 75 | long hdr_offset; /* event header offset */ |
| 76 | long payload_offset; /* event payload offset */ |
| 77 | u64 tsc; /* full 64-bits timestamp value */ |
| 78 | u32 data_size; |
| 79 | u16 chID; /* channel ID, const */ |
| 80 | u16 eID; |
| 81 | }; |
| 82 | |
| 83 | struct ltt_relay_iter { |
| 84 | struct ltt_relay_cpu_iter iter_cpu[NR_CPUS]; |
| 85 | struct ltt_chan *chan; |
| 86 | loff_t pos; |
| 87 | int cpu; |
| 88 | int nr_refs; |
| 89 | }; |
| 90 | |
| 91 | /* |
| 92 | * offset of 0 in subbuffer means "subbuf size" (filled subbuffer). |
| 93 | */ |
| 94 | static int is_subbuffer_offset_end(struct ltt_relay_cpu_iter *citer, |
| 95 | long offset) |
| 96 | { |
| 97 | struct ltt_chan *chan = container_of(citer->buf->a.chan, |
| 98 | struct ltt_chan, a); |
| 99 | long sub_offset = SUBBUF_OFFSET(offset - 1, chan) + 1; |
| 100 | |
| 101 | return (sub_offset <= citer->header->data_size); |
| 102 | } |
| 103 | |
| 104 | static u64 calculate_tsc(u64 pre_tsc, u64 read_tsc, unsigned int rflags) |
| 105 | { |
| 106 | u64 new_tsc = read_tsc; |
| 107 | |
| 108 | if (rflags != LTT_RFLAG_ID_SIZE_TSC) { |
| 109 | BUG_ON(read_tsc >> LTT_TSC_BITS); |
| 110 | |
| 111 | new_tsc = (pre_tsc & ~LTT_TSC_MASK) + read_tsc; |
| 112 | if (read_tsc < (pre_tsc & LTT_TSC_MASK)) |
| 113 | new_tsc += 1UL << LTT_TSC_BITS; |
| 114 | } |
| 115 | |
| 116 | return new_tsc; |
| 117 | } |
| 118 | |
| 119 | /* |
| 120 | * calculate payload offset */ |
| 121 | static inline long calculate_payload_offset(long offset, u16 chID, u16 eID) |
| 122 | { |
| 123 | const char *fmt; |
| 124 | |
| 125 | if (!ltt_get_alignment()) |
| 126 | return offset; |
| 127 | |
| 128 | fmt = marker_get_fmt_from_id(chID, eID); |
| 129 | BUG_ON(!fmt); |
| 130 | |
| 131 | return offset + ltt_fmt_largest_align(offset, fmt); |
| 132 | } |
| 133 | |
| 134 | static void update_new_event(struct ltt_relay_cpu_iter *citer, long hdr_offset) |
| 135 | { |
| 136 | u64 read_tsc; |
| 137 | unsigned int rflags; |
| 138 | long tmp_offset; |
| 139 | |
| 140 | WARN_ON_ONCE(hdr_offset != citer->hdr_offset); |
| 141 | |
| 142 | tmp_offset = ltt_read_event_header(&citer->buf->a, hdr_offset, |
| 143 | &read_tsc, &citer->data_size, |
| 144 | &citer->eID, &rflags); |
| 145 | citer->payload_offset = calculate_payload_offset(tmp_offset, |
| 146 | citer->chID, |
| 147 | citer->eID); |
| 148 | |
| 149 | citer->tsc = calculate_tsc(citer->tsc, read_tsc, rflags); |
| 150 | } |
| 151 | |
| 152 | static void update_event_size(struct ltt_relay_cpu_iter *citer, long hdr_offset) |
| 153 | { |
| 154 | char output[1]; |
| 155 | const char *fmt; |
| 156 | size_t data_size; |
| 157 | |
| 158 | if (citer->data_size != INT_MAX) |
| 159 | return; |
| 160 | |
| 161 | fmt = marker_get_fmt_from_id(citer->chID, citer->eID); |
| 162 | BUG_ON(!fmt); |
| 163 | ltt_serialize_printf(citer->buf, citer->payload_offset, |
| 164 | &data_size, output, 0, fmt); |
| 165 | citer->data_size = data_size; |
| 166 | } |
| 167 | |
| 168 | static void update_cpu_iter(struct ltt_relay_cpu_iter *citer, long hdr_offset) |
| 169 | { |
| 170 | if (unlikely((!citer->sb_ref) |
| 171 | || is_subbuffer_offset_end(citer, hdr_offset))) { |
| 172 | citer->header = NULL; |
| 173 | return; |
| 174 | } |
| 175 | update_new_event(citer, hdr_offset); |
| 176 | update_event_size(citer, hdr_offset); |
| 177 | } |
| 178 | |
| 179 | /* |
| 180 | * returns 0 if we get a subbuffer reference. |
| 181 | * else, the buffer has not available data, try again later. |
| 182 | */ |
| 183 | static int subbuffer_start(struct ltt_relay_cpu_iter *citer, long *offset) |
| 184 | { |
| 185 | int ret; |
| 186 | struct ltt_relay_iter *iter = citer->iter; |
| 187 | |
| 188 | ret = ltt_chanbuf_get_subbuf(citer->buf, offset); |
| 189 | if (!ret) { |
| 190 | citer->header = ltt_relay_read_offset_address(&citer->buf->a, |
| 191 | *offset); |
| 192 | citer->hdr_offset = (*offset) + ltt_sb_header_size(); |
| 193 | citer->tsc = citer->header->cycle_count_begin; |
| 194 | iter->nr_refs++; |
| 195 | citer->sb_ref = 1; |
| 196 | return 0; |
| 197 | } else { |
| 198 | if (ltt_chanbuf_is_finalized(citer->buf)) |
| 199 | return -ENODATA; |
| 200 | else |
| 201 | return -EAGAIN; |
| 202 | } |
| 203 | } |
| 204 | |
| 205 | static void subbuffer_stop(struct ltt_relay_cpu_iter *citer, |
| 206 | long offset) |
| 207 | { |
| 208 | int ret; |
| 209 | struct ltt_relay_iter *iter = citer->iter; |
| 210 | |
| 211 | WARN_ON_ONCE(!citer->sb_ref); |
| 212 | ret = ltt_chanbuf_put_subbuf(citer->buf, offset); |
| 213 | WARN_ON_ONCE(ret); |
| 214 | citer->sb_ref = 0; |
| 215 | iter->nr_refs--; |
| 216 | } |
| 217 | |
| 218 | static void ltt_relay_advance_cpu_iter(struct ltt_relay_cpu_iter *citer) |
| 219 | { |
| 220 | long old_offset = citer->payload_offset; |
| 221 | long new_offset = citer->payload_offset; |
| 222 | int ret; |
| 223 | |
| 224 | /* find that whether we read all data in this subbuffer */ |
| 225 | if (unlikely(is_subbuffer_offset_end(citer, |
| 226 | old_offset + citer->data_size))) { |
| 227 | DEBUGP(KERN_DEBUG "LTT ASCII stop cpu %d offset %lX\n", |
| 228 | citer->buf->a.cpu, citer->read_sb_offset); |
| 229 | subbuffer_stop(citer, citer->read_sb_offset); |
| 230 | for (;;) { |
| 231 | ret = subbuffer_start(citer, &citer->read_sb_offset); |
| 232 | DEBUGP(KERN_DEBUG |
| 233 | "LTT ASCII start cpu %d ret %d offset %lX\n", |
| 234 | citer->buf->a.cpu, ret, citer->read_sb_offset); |
| 235 | if (!ret || ret == -ENODATA) { |
| 236 | break; /* got data, or finalized */ |
| 237 | } else { /* -EAGAIN */ |
| 238 | if (signal_pending(current)) |
| 239 | break; |
| 240 | schedule_timeout_interruptible(1); |
| 241 | //TODO: check for no-data delay. take ref. break |
| 242 | } |
| 243 | } |
| 244 | } else { |
| 245 | new_offset += citer->data_size; |
| 246 | citer->hdr_offset = new_offset + ltt_align(new_offset, sizeof(struct ltt_event_header)); |
| 247 | DEBUGP(KERN_DEBUG |
| 248 | "LTT ASCII old_offset %lX new_offset %lX cpu %d\n", |
| 249 | old_offset, new_offset, citer->buf->a.cpu); |
| 250 | } |
| 251 | |
| 252 | update_cpu_iter(citer, citer->hdr_offset); |
| 253 | } |
| 254 | |
| 255 | static int cpu_iter_eof(struct ltt_relay_cpu_iter *citer) |
| 256 | { |
| 257 | return !citer->sb_ref; |
| 258 | } |
| 259 | |
| 260 | static int ltt_relay_iter_eof(struct ltt_relay_iter *iter) |
| 261 | { |
| 262 | return iter->nr_refs == 0; |
| 263 | } |
| 264 | |
| 265 | static void ltt_relay_advance_iter(struct ltt_relay_iter *iter) |
| 266 | { |
| 267 | int i; |
| 268 | struct ltt_relay_cpu_iter *curr, *min = NULL; |
| 269 | iter->cpu = -1; |
| 270 | |
| 271 | /* |
| 272 | * find the event with the minimum tsc. |
| 273 | * TODO: use min-heep for 4096CPUS |
| 274 | */ |
| 275 | for_each_possible_cpu(i) { |
| 276 | curr = &iter->iter_cpu[i]; |
| 277 | |
| 278 | if (!curr->buf->a.allocated || !curr->header) |
| 279 | continue; |
| 280 | |
| 281 | if (cpu_iter_eof(curr)) |
| 282 | continue; |
| 283 | |
| 284 | if (!min || curr->tsc < min->tsc) { |
| 285 | min = curr; |
| 286 | iter->cpu = i; |
| 287 | } |
| 288 | } |
| 289 | |
| 290 | /* update cpu_iter for next ltt_relay_advance_iter() */ |
| 291 | if (min) |
| 292 | ltt_relay_advance_cpu_iter(min); |
| 293 | } |
| 294 | |
| 295 | static void *ascii_next(struct seq_file *m, void *v, loff_t *ppos) |
| 296 | { |
| 297 | struct ltt_relay_iter *iter = m->private; |
| 298 | |
| 299 | WARN_ON_ONCE(!iter->nr_refs); |
| 300 | BUG_ON(v != iter); |
| 301 | |
| 302 | ltt_relay_advance_iter(iter); |
| 303 | return (ltt_relay_iter_eof(iter) || signal_pending(current)) |
| 304 | ? NULL : iter; |
| 305 | } |
| 306 | |
| 307 | static void *ascii_start(struct seq_file *m, loff_t *ppos) |
| 308 | { |
| 309 | struct ltt_relay_iter *iter = m->private; |
| 310 | |
| 311 | ltt_relay_advance_iter(iter); |
| 312 | return (ltt_relay_iter_eof(iter) || signal_pending(current)) |
| 313 | ? NULL : iter; |
| 314 | } |
| 315 | |
| 316 | static void ascii_stop(struct seq_file *m, void *v) |
| 317 | { |
| 318 | } |
| 319 | |
| 320 | static |
| 321 | int seq_serialize(struct seq_file *m, struct ltt_chanbuf *buf, |
| 322 | size_t buf_offset, const char *fmt, size_t *data_size) |
| 323 | { |
| 324 | int len; |
| 325 | |
| 326 | if (m->count < m->size) { |
| 327 | len = ltt_serialize_printf(buf, buf_offset, data_size, |
| 328 | m->buf + m->count, |
| 329 | m->size - m->count, fmt); |
| 330 | if (m->count + len < m->size) { |
| 331 | m->count += len; |
| 332 | return 0; |
| 333 | } |
| 334 | } |
| 335 | |
| 336 | m->count = m->size; |
| 337 | return -1; |
| 338 | } |
| 339 | |
| 340 | static int ascii_show(struct seq_file *m, void *v) |
| 341 | { |
| 342 | struct ltt_relay_iter *iter = v; |
| 343 | struct ltt_relay_cpu_iter *citer; |
| 344 | const char *name; |
| 345 | const char *fmt; |
| 346 | unsigned long long tsc; |
| 347 | size_t data_size; |
| 348 | |
| 349 | if (iter->cpu == -1) |
| 350 | return 0; |
| 351 | |
| 352 | citer = &iter->iter_cpu[iter->cpu]; |
| 353 | WARN_ON_ONCE(!citer->sb_ref); |
| 354 | /* |
| 355 | * Nothing to show, we are at the end of the last subbuffer currently |
| 356 | * having data. |
| 357 | */ |
| 358 | if (!citer->header) |
| 359 | return 0; |
| 360 | |
| 361 | tsc = citer->tsc; |
| 362 | name = marker_get_name_from_id(citer->chID, citer->eID); |
| 363 | fmt = marker_get_fmt_from_id(citer->chID, citer->eID); |
| 364 | |
| 365 | if (!name || !fmt) |
| 366 | return 0; |
| 367 | |
| 368 | seq_printf(m, "event:%16.16s: cpu:%2d time:%20.20llu ", |
| 369 | name, iter->cpu, tsc); |
| 370 | seq_serialize(m, citer->buf, citer->payload_offset, fmt, &data_size); |
| 371 | seq_puts(m, "\n"); |
| 372 | if (citer->data_size == INT_MAX) |
| 373 | citer->data_size = data_size; |
| 374 | |
| 375 | return 0; |
| 376 | } |
| 377 | |
| 378 | static struct seq_operations ascii_seq_ops = { |
| 379 | .start = ascii_start, |
| 380 | .next = ascii_next, |
| 381 | .stop = ascii_stop, |
| 382 | .show = ascii_show, |
| 383 | }; |
| 384 | |
| 385 | /* FIXME : cpu hotplug support */ |
| 386 | static int ltt_relay_iter_open_channel(struct ltt_relay_iter *iter, |
| 387 | struct ltt_chan *chan) |
| 388 | { |
| 389 | int i, ret; |
| 390 | u16 chID = ltt_channels_get_index_from_name(chan->a.filename); |
| 391 | |
| 392 | /* we don't need lock relay_channels_mutex */ |
| 393 | for_each_possible_cpu(i) { |
| 394 | struct ltt_relay_cpu_iter *citer = &iter->iter_cpu[i]; |
| 395 | |
| 396 | citer->buf = per_cpu_ptr(chan->a.buf, i); |
| 397 | if (!citer->buf->a.allocated) |
| 398 | continue; |
| 399 | |
| 400 | citer->iter = iter; /* easy lazy parent info */ |
| 401 | citer->chID = chID; |
| 402 | |
| 403 | ret = ltt_chanbuf_open_read(citer->buf); |
| 404 | if (ret) { |
| 405 | /* Failed to open a percpu buffer, close everything. */ |
| 406 | citer->buf = NULL; |
| 407 | goto error; |
| 408 | } |
| 409 | |
| 410 | for (;;) { |
| 411 | ret = subbuffer_start(citer, |
| 412 | &citer->read_sb_offset); |
| 413 | DEBUGP(KERN_DEBUG |
| 414 | "LTT ASCII open start " |
| 415 | "cpu %d ret %d offset %lX\n", |
| 416 | citer->buf->a.cpu, ret, citer->read_sb_offset); |
| 417 | if (!ret || ret == -ENODATA) { |
| 418 | break; /* got data, or finalized */ |
| 419 | } else { /* -EAGAIN */ |
| 420 | if (signal_pending(current)) |
| 421 | break; |
| 422 | schedule_timeout_interruptible(1); |
| 423 | } |
| 424 | } |
| 425 | update_cpu_iter(citer, citer->hdr_offset); |
| 426 | } |
| 427 | if (!iter->nr_refs) { |
| 428 | ret = -ENODATA; |
| 429 | goto error; |
| 430 | } |
| 431 | |
| 432 | return 0; |
| 433 | |
| 434 | error: |
| 435 | for_each_possible_cpu(i) { |
| 436 | struct ltt_relay_cpu_iter *citer = &iter->iter_cpu[i]; |
| 437 | |
| 438 | if (!citer->buf) |
| 439 | break; |
| 440 | |
| 441 | if (citer->buf->a.allocated) |
| 442 | ltt_chanbuf_release_read(citer->buf); |
| 443 | } |
| 444 | return ret; |
| 445 | } |
| 446 | |
| 447 | /* FIXME : cpu hotplug support */ |
| 448 | static int ltt_relay_iter_release_channel(struct ltt_relay_iter *iter) |
| 449 | { |
| 450 | int i; |
| 451 | |
| 452 | for_each_possible_cpu(i) { |
| 453 | struct ltt_relay_cpu_iter *citer = &iter->iter_cpu[i]; |
| 454 | |
| 455 | if (citer->sb_ref) { |
| 456 | WARN_ON_ONCE(!citer->buf->a.allocated); |
| 457 | DEBUGP(KERN_DEBUG |
| 458 | "LTT ASCII release stop cpu %d offset %lX\n", |
| 459 | citer->buf->a.cpu, citer->read_sb_offset); |
| 460 | subbuffer_stop(&iter->iter_cpu[i], |
| 461 | citer->read_sb_offset); |
| 462 | } |
| 463 | if (citer->buf->a.allocated) |
| 464 | ltt_chanbuf_release_read(citer->buf); |
| 465 | } |
| 466 | WARN_ON_ONCE(iter->nr_refs); |
| 467 | return 0; |
| 468 | } |
| 469 | |
| 470 | static int ltt_relay_ascii_open(struct inode *inode, struct file *file) |
| 471 | { |
| 472 | int ret; |
| 473 | struct ltt_chan *chan = inode->i_private; |
| 474 | struct ltt_relay_iter *iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
| 475 | if (!iter) |
| 476 | return -ENOMEM; |
| 477 | |
| 478 | iter->chan = chan; |
| 479 | ret = ltt_relay_iter_open_channel(iter, chan); |
| 480 | if (ret) |
| 481 | goto error_free_alloc; |
| 482 | |
| 483 | ret = seq_open(file, &ascii_seq_ops); |
| 484 | if (ret) |
| 485 | goto error_release_channel; |
| 486 | ((struct seq_file *)file->private_data)->private = iter; |
| 487 | return 0; |
| 488 | |
| 489 | error_release_channel: |
| 490 | ltt_relay_iter_release_channel(iter); |
| 491 | error_free_alloc: |
| 492 | kfree(iter); |
| 493 | return ret; |
| 494 | } |
| 495 | |
| 496 | static int ltt_relay_ascii_release(struct inode *inode, struct file *file) |
| 497 | { |
| 498 | struct seq_file *seq = file->private_data; |
| 499 | struct ltt_relay_iter *iter = seq->private; |
| 500 | |
| 501 | ltt_relay_iter_release_channel(iter); |
| 502 | kfree(iter); |
| 503 | return 0; |
| 504 | } |
| 505 | |
| 506 | static struct file_operations ltt_ascii_fops = |
| 507 | { |
| 508 | .read = seq_read, |
| 509 | .open = ltt_relay_ascii_open, |
| 510 | .release = ltt_relay_ascii_release, |
| 511 | .llseek = no_llseek, |
| 512 | .owner = THIS_MODULE, |
| 513 | }; |
| 514 | |
| 515 | int ltt_ascii_create(struct ltt_chan *chan) |
| 516 | { |
| 517 | struct dentry *dentry; |
| 518 | |
| 519 | dentry = debugfs_create_file(chan->a.filename, |
| 520 | S_IRUSR | S_IRGRP, |
| 521 | chan->a.trace->dentry.ascii_root, |
| 522 | chan, <t_ascii_fops); |
| 523 | if (IS_ERR(dentry)) |
| 524 | return PTR_ERR(dentry); |
| 525 | |
| 526 | if (!dentry) |
| 527 | return -EEXIST; |
| 528 | |
| 529 | chan->a.ascii_dentry = dentry; |
| 530 | dentry->d_inode->i_private = chan; |
| 531 | return 0; |
| 532 | } |
| 533 | EXPORT_SYMBOL_GPL(ltt_ascii_create); |
| 534 | |
| 535 | void ltt_ascii_remove(struct ltt_chan *chan) |
| 536 | { |
| 537 | struct dentry *dentry; |
| 538 | |
| 539 | dentry = dget(chan->a.ascii_dentry); |
| 540 | debugfs_remove(dentry); |
| 541 | /* TODO: wait / wakeup instead */ |
| 542 | /* |
| 543 | * Wait for every reference to the dentry to be gone, |
| 544 | * except us. |
| 545 | */ |
| 546 | while (atomic_read(&dentry->d_count) != 1) |
| 547 | msleep(100); |
| 548 | dput(dentry); |
| 549 | } |
| 550 | EXPORT_SYMBOL_GPL(ltt_ascii_remove); |
| 551 | |
| 552 | int ltt_ascii_create_dir(struct ltt_trace *new_trace) |
| 553 | { |
| 554 | new_trace->dentry.ascii_root = debugfs_create_dir(new_trace->trace_name, |
| 555 | ltt_ascii_dir_dentry); |
| 556 | if (!new_trace->dentry.ascii_root) |
| 557 | return -EEXIST; |
| 558 | return 0; |
| 559 | } |
| 560 | EXPORT_SYMBOL_GPL(ltt_ascii_create_dir); |
| 561 | |
| 562 | void ltt_ascii_remove_dir(struct ltt_trace *trace) |
| 563 | { |
| 564 | debugfs_remove(trace->dentry.ascii_root); |
| 565 | } |
| 566 | EXPORT_SYMBOL_GPL(ltt_ascii_remove_dir); |
| 567 | |
| 568 | __init int ltt_ascii_init(void) |
| 569 | { |
| 570 | ltt_ascii_dir_dentry = debugfs_create_dir(LTT_ASCII, get_ltt_root()); |
| 571 | |
| 572 | return ltt_ascii_dir_dentry ? 0 : -EFAULT; |
| 573 | } |
| 574 | |
| 575 | __exit void ltt_ascii_exit(void) |
| 576 | { |
| 577 | debugfs_remove(ltt_ascii_dir_dentry); |
| 578 | put_ltt_root(); |
| 579 | } |
| 580 | |
| 581 | MODULE_LICENSE("GPL and additional rights"); |
| 582 | MODULE_AUTHOR("Lai Jiangshan@FNST and Mathieu Desnoyers"); |
| 583 | MODULE_DESCRIPTION("Linux Trace Toolkit Next Generation Ascii Converter"); |