Commit | Line | Data |
---|---|---|
2056a782 | 1 | /* |
0fe23479 | 2 | * Copyright (C) 2006 Jens Axboe <axboe@kernel.dk> |
2056a782 JA |
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 | * This program is distributed in the hope that it will be useful, | |
9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
11 | * GNU General Public License for more details. | |
12 | * | |
13 | * You should have received a copy of the GNU General Public License | |
14 | * along with this program; if not, write to the Free Software | |
15 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
16 | * | |
17 | */ | |
2056a782 JA |
18 | #include <linux/kernel.h> |
19 | #include <linux/blkdev.h> | |
20 | #include <linux/blktrace_api.h> | |
21 | #include <linux/percpu.h> | |
22 | #include <linux/init.h> | |
23 | #include <linux/mutex.h> | |
24 | #include <linux/debugfs.h> | |
405f5571 | 25 | #include <linux/smp_lock.h> |
be1c6341 | 26 | #include <linux/time.h> |
939b3669 | 27 | #include <linux/uaccess.h> |
55782138 LZ |
28 | |
29 | #include <trace/events/block.h> | |
30 | ||
2db270a8 | 31 | #include "trace_output.h" |
2056a782 | 32 | |
55782138 LZ |
33 | #ifdef CONFIG_BLK_DEV_IO_TRACE |
34 | ||
2056a782 JA |
35 | static unsigned int blktrace_seq __read_mostly = 1; |
36 | ||
c71a8961 | 37 | static struct trace_array *blk_tr; |
5006ea73 | 38 | static bool blk_tracer_enabled __read_mostly; |
c71a8961 ACM |
39 | |
40 | /* Select an alternative, minimalistic output than the original one */ | |
ef18012b | 41 | #define TRACE_BLK_OPT_CLASSIC 0x1 |
c71a8961 ACM |
42 | |
43 | static struct tracer_opt blk_tracer_opts[] = { | |
44 | /* Default disable the minimalistic output */ | |
157f9c00 | 45 | { TRACER_OPT(blk_classic, TRACE_BLK_OPT_CLASSIC) }, |
c71a8961 ACM |
46 | { } |
47 | }; | |
48 | ||
49 | static struct tracer_flags blk_tracer_flags = { | |
50 | .val = 0, | |
51 | .opts = blk_tracer_opts, | |
52 | }; | |
53 | ||
5f3ea37c | 54 | /* Global reference count of probes */ |
5f3ea37c ACM |
55 | static atomic_t blk_probes_ref = ATOMIC_INIT(0); |
56 | ||
3c289ba7 | 57 | static void blk_register_tracepoints(void); |
5f3ea37c ACM |
58 | static void blk_unregister_tracepoints(void); |
59 | ||
be1c6341 OK |
60 | /* |
61 | * Send out a notify message. | |
62 | */ | |
a863055b JA |
63 | static void trace_note(struct blk_trace *bt, pid_t pid, int action, |
64 | const void *data, size_t len) | |
be1c6341 OK |
65 | { |
66 | struct blk_io_trace *t; | |
18cea459 LZ |
67 | struct ring_buffer_event *event = NULL; |
68 | int pc = 0; | |
69 | int cpu = smp_processor_id(); | |
70 | bool blk_tracer = blk_tracer_enabled; | |
71 | ||
72 | if (blk_tracer) { | |
73 | pc = preempt_count(); | |
74 | event = trace_buffer_lock_reserve(blk_tr, TRACE_BLK, | |
75 | sizeof(*t) + len, | |
76 | 0, pc); | |
77 | if (!event) | |
78 | return; | |
79 | t = ring_buffer_event_data(event); | |
80 | goto record_it; | |
81 | } | |
be1c6341 | 82 | |
c71a8961 ACM |
83 | if (!bt->rchan) |
84 | return; | |
85 | ||
be1c6341 | 86 | t = relay_reserve(bt->rchan, sizeof(*t) + len); |
d3d9d2a5 | 87 | if (t) { |
d3d9d2a5 | 88 | t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; |
2997c8c4 | 89 | t->time = ktime_to_ns(ktime_get()); |
18cea459 | 90 | record_it: |
d3d9d2a5 JA |
91 | t->device = bt->dev; |
92 | t->action = action; | |
93 | t->pid = pid; | |
94 | t->cpu = cpu; | |
95 | t->pdu_len = len; | |
96 | memcpy((void *) t + sizeof(*t), data, len); | |
18cea459 LZ |
97 | |
98 | if (blk_tracer) | |
99 | trace_buffer_unlock_commit(blk_tr, event, 0, pc); | |
d3d9d2a5 | 100 | } |
be1c6341 OK |
101 | } |
102 | ||
2056a782 JA |
103 | /* |
104 | * Send out a notify for this process, if we haven't done so since a trace | |
105 | * started | |
106 | */ | |
107 | static void trace_note_tsk(struct blk_trace *bt, struct task_struct *tsk) | |
108 | { | |
a863055b JA |
109 | tsk->btrace_seq = blktrace_seq; |
110 | trace_note(bt, tsk->pid, BLK_TN_PROCESS, tsk->comm, sizeof(tsk->comm)); | |
be1c6341 | 111 | } |
2056a782 | 112 | |
be1c6341 OK |
113 | static void trace_note_time(struct blk_trace *bt) |
114 | { | |
115 | struct timespec now; | |
116 | unsigned long flags; | |
117 | u32 words[2]; | |
118 | ||
119 | getnstimeofday(&now); | |
120 | words[0] = now.tv_sec; | |
121 | words[1] = now.tv_nsec; | |
122 | ||
123 | local_irq_save(flags); | |
124 | trace_note(bt, 0, BLK_TN_TIMESTAMP, words, sizeof(words)); | |
125 | local_irq_restore(flags); | |
2056a782 JA |
126 | } |
127 | ||
9d5f09a4 AB |
128 | void __trace_note_message(struct blk_trace *bt, const char *fmt, ...) |
129 | { | |
130 | int n; | |
131 | va_list args; | |
14a73f54 | 132 | unsigned long flags; |
64565911 | 133 | char *buf; |
9d5f09a4 | 134 | |
18cea459 LZ |
135 | if (unlikely(bt->trace_state != Blktrace_running && |
136 | !blk_tracer_enabled)) | |
c71a8961 ACM |
137 | return; |
138 | ||
14a73f54 | 139 | local_irq_save(flags); |
64565911 | 140 | buf = per_cpu_ptr(bt->msg_data, smp_processor_id()); |
9d5f09a4 | 141 | va_start(args, fmt); |
64565911 | 142 | n = vscnprintf(buf, BLK_TN_MAX_MSG, fmt, args); |
9d5f09a4 AB |
143 | va_end(args); |
144 | ||
64565911 | 145 | trace_note(bt, 0, BLK_TN_MESSAGE, buf, n); |
14a73f54 | 146 | local_irq_restore(flags); |
9d5f09a4 AB |
147 | } |
148 | EXPORT_SYMBOL_GPL(__trace_note_message); | |
149 | ||
2056a782 JA |
150 | static int act_log_check(struct blk_trace *bt, u32 what, sector_t sector, |
151 | pid_t pid) | |
152 | { | |
153 | if (((bt->act_mask << BLK_TC_SHIFT) & what) == 0) | |
154 | return 1; | |
d0deef5b | 155 | if (sector && (sector < bt->start_lba || sector > bt->end_lba)) |
2056a782 JA |
156 | return 1; |
157 | if (bt->pid && pid != bt->pid) | |
158 | return 1; | |
159 | ||
160 | return 0; | |
161 | } | |
162 | ||
163 | /* | |
164 | * Data direction bit lookup | |
165 | */ | |
e4955c99 LZ |
166 | static const u32 ddir_act[2] = { BLK_TC_ACT(BLK_TC_READ), |
167 | BLK_TC_ACT(BLK_TC_WRITE) }; | |
2056a782 | 168 | |
35ba8f70 | 169 | /* The ilog2() calls fall out because they're constant */ |
939b3669 ACM |
170 | #define MASK_TC_BIT(rw, __name) ((rw & (1 << BIO_RW_ ## __name)) << \ |
171 | (ilog2(BLK_TC_ ## __name) + BLK_TC_SHIFT - BIO_RW_ ## __name)) | |
2056a782 JA |
172 | |
173 | /* | |
174 | * The worker for the various blk_add_trace*() types. Fills out a | |
175 | * blk_io_trace structure and places it in a per-cpu subbuffer. | |
176 | */ | |
5f3ea37c | 177 | static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, |
2056a782 JA |
178 | int rw, u32 what, int error, int pdu_len, void *pdu_data) |
179 | { | |
180 | struct task_struct *tsk = current; | |
c71a8961 | 181 | struct ring_buffer_event *event = NULL; |
2056a782 | 182 | struct blk_io_trace *t; |
0a987751 | 183 | unsigned long flags = 0; |
2056a782 JA |
184 | unsigned long *sequence; |
185 | pid_t pid; | |
c71a8961 | 186 | int cpu, pc = 0; |
18cea459 | 187 | bool blk_tracer = blk_tracer_enabled; |
2056a782 | 188 | |
18cea459 | 189 | if (unlikely(bt->trace_state != Blktrace_running && !blk_tracer)) |
2056a782 JA |
190 | return; |
191 | ||
192 | what |= ddir_act[rw & WRITE]; | |
35ba8f70 | 193 | what |= MASK_TC_BIT(rw, BARRIER); |
93dbb393 | 194 | what |= MASK_TC_BIT(rw, SYNCIO); |
35ba8f70 DW |
195 | what |= MASK_TC_BIT(rw, AHEAD); |
196 | what |= MASK_TC_BIT(rw, META); | |
197 | what |= MASK_TC_BIT(rw, DISCARD); | |
2056a782 JA |
198 | |
199 | pid = tsk->pid; | |
d0deef5b | 200 | if (act_log_check(bt, what, sector, pid)) |
2056a782 | 201 | return; |
c71a8961 ACM |
202 | cpu = raw_smp_processor_id(); |
203 | ||
18cea459 | 204 | if (blk_tracer) { |
c71a8961 ACM |
205 | tracing_record_cmdline(current); |
206 | ||
51a763dd ACM |
207 | pc = preempt_count(); |
208 | event = trace_buffer_lock_reserve(blk_tr, TRACE_BLK, | |
209 | sizeof(*t) + pdu_len, | |
210 | 0, pc); | |
c71a8961 ACM |
211 | if (!event) |
212 | return; | |
51a763dd | 213 | t = ring_buffer_event_data(event); |
c71a8961 ACM |
214 | goto record_it; |
215 | } | |
2056a782 JA |
216 | |
217 | /* | |
218 | * A word about the locking here - we disable interrupts to reserve | |
219 | * some space in the relay per-cpu buffer, to prevent an irq | |
14a73f54 | 220 | * from coming in and stepping on our toes. |
2056a782 JA |
221 | */ |
222 | local_irq_save(flags); | |
223 | ||
224 | if (unlikely(tsk->btrace_seq != blktrace_seq)) | |
225 | trace_note_tsk(bt, tsk); | |
226 | ||
227 | t = relay_reserve(bt->rchan, sizeof(*t) + pdu_len); | |
228 | if (t) { | |
2056a782 JA |
229 | sequence = per_cpu_ptr(bt->sequence, cpu); |
230 | ||
231 | t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; | |
232 | t->sequence = ++(*sequence); | |
2997c8c4 | 233 | t->time = ktime_to_ns(ktime_get()); |
c71a8961 | 234 | record_it: |
08a06b83 | 235 | /* |
939b3669 ACM |
236 | * These two are not needed in ftrace as they are in the |
237 | * generic trace_entry, filled by tracing_generic_entry_update, | |
238 | * but for the trace_event->bin() synthesizer benefit we do it | |
239 | * here too. | |
240 | */ | |
241 | t->cpu = cpu; | |
242 | t->pid = pid; | |
08a06b83 | 243 | |
2056a782 JA |
244 | t->sector = sector; |
245 | t->bytes = bytes; | |
246 | t->action = what; | |
2056a782 | 247 | t->device = bt->dev; |
2056a782 JA |
248 | t->error = error; |
249 | t->pdu_len = pdu_len; | |
250 | ||
251 | if (pdu_len) | |
252 | memcpy((void *) t + sizeof(*t), pdu_data, pdu_len); | |
c71a8961 | 253 | |
18cea459 | 254 | if (blk_tracer) { |
51a763dd | 255 | trace_buffer_unlock_commit(blk_tr, event, 0, pc); |
c71a8961 ACM |
256 | return; |
257 | } | |
2056a782 JA |
258 | } |
259 | ||
260 | local_irq_restore(flags); | |
261 | } | |
262 | ||
2056a782 | 263 | static struct dentry *blk_tree_root; |
11a57153 | 264 | static DEFINE_MUTEX(blk_tree_mutex); |
2056a782 | 265 | |
ad5dd549 | 266 | static void blk_trace_free(struct blk_trace *bt) |
2056a782 | 267 | { |
02c62304 | 268 | debugfs_remove(bt->msg_file); |
2056a782 | 269 | debugfs_remove(bt->dropped_file); |
fd51d251 | 270 | debugfs_remove(bt->dir); |
f48fc4d3 | 271 | relay_close(bt->rchan); |
2056a782 | 272 | free_percpu(bt->sequence); |
64565911 | 273 | free_percpu(bt->msg_data); |
2056a782 | 274 | kfree(bt); |
ad5dd549 LZ |
275 | } |
276 | ||
277 | static void blk_trace_cleanup(struct blk_trace *bt) | |
278 | { | |
279 | blk_trace_free(bt); | |
5f3ea37c ACM |
280 | if (atomic_dec_and_test(&blk_probes_ref)) |
281 | blk_unregister_tracepoints(); | |
2056a782 JA |
282 | } |
283 | ||
6da127ad | 284 | int blk_trace_remove(struct request_queue *q) |
2056a782 JA |
285 | { |
286 | struct blk_trace *bt; | |
287 | ||
288 | bt = xchg(&q->blk_trace, NULL); | |
289 | if (!bt) | |
290 | return -EINVAL; | |
291 | ||
55547204 | 292 | if (bt->trace_state != Blktrace_running) |
2056a782 JA |
293 | blk_trace_cleanup(bt); |
294 | ||
295 | return 0; | |
296 | } | |
6da127ad | 297 | EXPORT_SYMBOL_GPL(blk_trace_remove); |
2056a782 JA |
298 | |
299 | static int blk_dropped_open(struct inode *inode, struct file *filp) | |
300 | { | |
8e18e294 | 301 | filp->private_data = inode->i_private; |
2056a782 JA |
302 | |
303 | return 0; | |
304 | } | |
305 | ||
306 | static ssize_t blk_dropped_read(struct file *filp, char __user *buffer, | |
307 | size_t count, loff_t *ppos) | |
308 | { | |
309 | struct blk_trace *bt = filp->private_data; | |
310 | char buf[16]; | |
311 | ||
312 | snprintf(buf, sizeof(buf), "%u\n", atomic_read(&bt->dropped)); | |
313 | ||
314 | return simple_read_from_buffer(buffer, count, ppos, buf, strlen(buf)); | |
315 | } | |
316 | ||
2b8693c0 | 317 | static const struct file_operations blk_dropped_fops = { |
2056a782 JA |
318 | .owner = THIS_MODULE, |
319 | .open = blk_dropped_open, | |
320 | .read = blk_dropped_read, | |
321 | }; | |
322 | ||
02c62304 AB |
323 | static int blk_msg_open(struct inode *inode, struct file *filp) |
324 | { | |
325 | filp->private_data = inode->i_private; | |
326 | ||
327 | return 0; | |
328 | } | |
329 | ||
330 | static ssize_t blk_msg_write(struct file *filp, const char __user *buffer, | |
331 | size_t count, loff_t *ppos) | |
332 | { | |
333 | char *msg; | |
334 | struct blk_trace *bt; | |
335 | ||
7635b03a | 336 | if (count >= BLK_TN_MAX_MSG) |
02c62304 AB |
337 | return -EINVAL; |
338 | ||
a4b3ada8 | 339 | msg = kmalloc(count + 1, GFP_KERNEL); |
02c62304 AB |
340 | if (msg == NULL) |
341 | return -ENOMEM; | |
342 | ||
343 | if (copy_from_user(msg, buffer, count)) { | |
344 | kfree(msg); | |
345 | return -EFAULT; | |
346 | } | |
347 | ||
a4b3ada8 | 348 | msg[count] = '\0'; |
02c62304 AB |
349 | bt = filp->private_data; |
350 | __trace_note_message(bt, "%s", msg); | |
351 | kfree(msg); | |
352 | ||
353 | return count; | |
354 | } | |
355 | ||
356 | static const struct file_operations blk_msg_fops = { | |
357 | .owner = THIS_MODULE, | |
358 | .open = blk_msg_open, | |
359 | .write = blk_msg_write, | |
360 | }; | |
361 | ||
2056a782 JA |
362 | /* |
363 | * Keep track of how many times we encountered a full subbuffer, to aid | |
364 | * the user space app in telling how many lost events there were. | |
365 | */ | |
366 | static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf, | |
367 | void *prev_subbuf, size_t prev_padding) | |
368 | { | |
369 | struct blk_trace *bt; | |
370 | ||
371 | if (!relay_buf_full(buf)) | |
372 | return 1; | |
373 | ||
374 | bt = buf->chan->private_data; | |
375 | atomic_inc(&bt->dropped); | |
376 | return 0; | |
377 | } | |
378 | ||
379 | static int blk_remove_buf_file_callback(struct dentry *dentry) | |
380 | { | |
f48fc4d3 | 381 | struct dentry *parent = dentry->d_parent; |
2056a782 | 382 | debugfs_remove(dentry); |
f48fc4d3 JA |
383 | |
384 | /* | |
385 | * this will fail for all but the last file, but that is ok. what we | |
386 | * care about is the top level buts->name directory going away, when | |
387 | * the last trace file is gone. Then we don't have to rmdir() that | |
388 | * manually on trace stop, so it nicely solves the issue with | |
389 | * force killing of running traces. | |
390 | */ | |
391 | ||
392 | debugfs_remove(parent); | |
2056a782 JA |
393 | return 0; |
394 | } | |
395 | ||
396 | static struct dentry *blk_create_buf_file_callback(const char *filename, | |
397 | struct dentry *parent, | |
398 | int mode, | |
399 | struct rchan_buf *buf, | |
400 | int *is_global) | |
401 | { | |
402 | return debugfs_create_file(filename, mode, parent, buf, | |
403 | &relay_file_operations); | |
404 | } | |
405 | ||
406 | static struct rchan_callbacks blk_relay_callbacks = { | |
407 | .subbuf_start = blk_subbuf_start_callback, | |
408 | .create_buf_file = blk_create_buf_file_callback, | |
409 | .remove_buf_file = blk_remove_buf_file_callback, | |
410 | }; | |
411 | ||
9908c309 LZ |
412 | static void blk_trace_setup_lba(struct blk_trace *bt, |
413 | struct block_device *bdev) | |
414 | { | |
415 | struct hd_struct *part = NULL; | |
416 | ||
417 | if (bdev) | |
418 | part = bdev->bd_part; | |
419 | ||
420 | if (part) { | |
421 | bt->start_lba = part->start_sect; | |
422 | bt->end_lba = part->start_sect + part->nr_sects; | |
423 | } else { | |
424 | bt->start_lba = 0; | |
425 | bt->end_lba = -1ULL; | |
426 | } | |
427 | } | |
428 | ||
2056a782 JA |
429 | /* |
430 | * Setup everything required to start tracing | |
431 | */ | |
6da127ad | 432 | int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, |
d0deef5b SD |
433 | struct block_device *bdev, |
434 | struct blk_user_trace_setup *buts) | |
2056a782 | 435 | { |
2056a782 JA |
436 | struct blk_trace *old_bt, *bt = NULL; |
437 | struct dentry *dir = NULL; | |
2056a782 JA |
438 | int ret, i; |
439 | ||
171044d4 | 440 | if (!buts->buf_size || !buts->buf_nr) |
2056a782 JA |
441 | return -EINVAL; |
442 | ||
0497b345 JA |
443 | strncpy(buts->name, name, BLKTRACE_BDEV_SIZE); |
444 | buts->name[BLKTRACE_BDEV_SIZE - 1] = '\0'; | |
2056a782 JA |
445 | |
446 | /* | |
447 | * some device names have larger paths - convert the slashes | |
448 | * to underscores for this to work as expected | |
449 | */ | |
171044d4 AB |
450 | for (i = 0; i < strlen(buts->name); i++) |
451 | if (buts->name[i] == '/') | |
452 | buts->name[i] = '_'; | |
2056a782 | 453 | |
2056a782 JA |
454 | bt = kzalloc(sizeof(*bt), GFP_KERNEL); |
455 | if (!bt) | |
ad5dd549 | 456 | return -ENOMEM; |
2056a782 | 457 | |
ad5dd549 | 458 | ret = -ENOMEM; |
2056a782 JA |
459 | bt->sequence = alloc_percpu(unsigned long); |
460 | if (!bt->sequence) | |
461 | goto err; | |
462 | ||
313e458f | 463 | bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); |
64565911 JA |
464 | if (!bt->msg_data) |
465 | goto err; | |
466 | ||
2056a782 | 467 | ret = -ENOENT; |
f48fc4d3 | 468 | |
b5230b56 | 469 | mutex_lock(&blk_tree_mutex); |
f48fc4d3 JA |
470 | if (!blk_tree_root) { |
471 | blk_tree_root = debugfs_create_dir("block", NULL); | |
b5230b56 LZ |
472 | if (!blk_tree_root) { |
473 | mutex_unlock(&blk_tree_mutex); | |
1a17662e | 474 | goto err; |
b5230b56 | 475 | } |
f48fc4d3 | 476 | } |
b5230b56 | 477 | mutex_unlock(&blk_tree_mutex); |
f48fc4d3 JA |
478 | |
479 | dir = debugfs_create_dir(buts->name, blk_tree_root); | |
480 | ||
2056a782 JA |
481 | if (!dir) |
482 | goto err; | |
483 | ||
484 | bt->dir = dir; | |
6da127ad | 485 | bt->dev = dev; |
2056a782 JA |
486 | atomic_set(&bt->dropped, 0); |
487 | ||
488 | ret = -EIO; | |
939b3669 ACM |
489 | bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt, |
490 | &blk_dropped_fops); | |
2056a782 JA |
491 | if (!bt->dropped_file) |
492 | goto err; | |
493 | ||
02c62304 AB |
494 | bt->msg_file = debugfs_create_file("msg", 0222, dir, bt, &blk_msg_fops); |
495 | if (!bt->msg_file) | |
496 | goto err; | |
497 | ||
171044d4 AB |
498 | bt->rchan = relay_open("trace", dir, buts->buf_size, |
499 | buts->buf_nr, &blk_relay_callbacks, bt); | |
2056a782 JA |
500 | if (!bt->rchan) |
501 | goto err; | |
2056a782 | 502 | |
171044d4 | 503 | bt->act_mask = buts->act_mask; |
2056a782 JA |
504 | if (!bt->act_mask) |
505 | bt->act_mask = (u16) -1; | |
506 | ||
9908c309 | 507 | blk_trace_setup_lba(bt, bdev); |
2056a782 | 508 | |
d0deef5b SD |
509 | /* overwrite with user settings */ |
510 | if (buts->start_lba) | |
511 | bt->start_lba = buts->start_lba; | |
512 | if (buts->end_lba) | |
513 | bt->end_lba = buts->end_lba; | |
514 | ||
171044d4 | 515 | bt->pid = buts->pid; |
2056a782 JA |
516 | bt->trace_state = Blktrace_setup; |
517 | ||
518 | ret = -EBUSY; | |
519 | old_bt = xchg(&q->blk_trace, bt); | |
520 | if (old_bt) { | |
521 | (void) xchg(&q->blk_trace, old_bt); | |
522 | goto err; | |
523 | } | |
524 | ||
17ba97e3 | 525 | if (atomic_inc_return(&blk_probes_ref) == 1) |
cbe28296 LZ |
526 | blk_register_tracepoints(); |
527 | ||
2056a782 JA |
528 | return 0; |
529 | err: | |
ad5dd549 | 530 | blk_trace_free(bt); |
2056a782 JA |
531 | return ret; |
532 | } | |
171044d4 | 533 | |
6da127ad | 534 | int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, |
d0deef5b | 535 | struct block_device *bdev, |
6da127ad | 536 | char __user *arg) |
171044d4 AB |
537 | { |
538 | struct blk_user_trace_setup buts; | |
539 | int ret; | |
540 | ||
541 | ret = copy_from_user(&buts, arg, sizeof(buts)); | |
542 | if (ret) | |
543 | return -EFAULT; | |
544 | ||
d0deef5b | 545 | ret = do_blk_trace_setup(q, name, dev, bdev, &buts); |
171044d4 AB |
546 | if (ret) |
547 | return ret; | |
548 | ||
549 | if (copy_to_user(arg, &buts, sizeof(buts))) | |
550 | return -EFAULT; | |
551 | ||
552 | return 0; | |
553 | } | |
6da127ad | 554 | EXPORT_SYMBOL_GPL(blk_trace_setup); |
2056a782 | 555 | |
6da127ad | 556 | int blk_trace_startstop(struct request_queue *q, int start) |
2056a782 | 557 | { |
2056a782 | 558 | int ret; |
939b3669 | 559 | struct blk_trace *bt = q->blk_trace; |
2056a782 | 560 | |
939b3669 | 561 | if (bt == NULL) |
2056a782 JA |
562 | return -EINVAL; |
563 | ||
564 | /* | |
565 | * For starting a trace, we can transition from a setup or stopped | |
566 | * trace. For stopping a trace, the state must be running | |
567 | */ | |
568 | ret = -EINVAL; | |
569 | if (start) { | |
570 | if (bt->trace_state == Blktrace_setup || | |
571 | bt->trace_state == Blktrace_stopped) { | |
572 | blktrace_seq++; | |
573 | smp_mb(); | |
574 | bt->trace_state = Blktrace_running; | |
be1c6341 OK |
575 | |
576 | trace_note_time(bt); | |
2056a782 JA |
577 | ret = 0; |
578 | } | |
579 | } else { | |
580 | if (bt->trace_state == Blktrace_running) { | |
581 | bt->trace_state = Blktrace_stopped; | |
582 | relay_flush(bt->rchan); | |
583 | ret = 0; | |
584 | } | |
585 | } | |
586 | ||
587 | return ret; | |
588 | } | |
6da127ad | 589 | EXPORT_SYMBOL_GPL(blk_trace_startstop); |
2056a782 JA |
590 | |
591 | /** | |
592 | * blk_trace_ioctl: - handle the ioctls associated with tracing | |
593 | * @bdev: the block device | |
ef18012b | 594 | * @cmd: the ioctl cmd |
2056a782 JA |
595 | * @arg: the argument data, if any |
596 | * | |
597 | **/ | |
598 | int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) | |
599 | { | |
165125e1 | 600 | struct request_queue *q; |
2056a782 | 601 | int ret, start = 0; |
6da127ad | 602 | char b[BDEVNAME_SIZE]; |
2056a782 JA |
603 | |
604 | q = bdev_get_queue(bdev); | |
605 | if (!q) | |
606 | return -ENXIO; | |
607 | ||
608 | mutex_lock(&bdev->bd_mutex); | |
609 | ||
610 | switch (cmd) { | |
611 | case BLKTRACESETUP: | |
f36f21ec | 612 | bdevname(bdev, b); |
d0deef5b | 613 | ret = blk_trace_setup(q, b, bdev->bd_dev, bdev, arg); |
2056a782 JA |
614 | break; |
615 | case BLKTRACESTART: | |
616 | start = 1; | |
617 | case BLKTRACESTOP: | |
618 | ret = blk_trace_startstop(q, start); | |
619 | break; | |
620 | case BLKTRACETEARDOWN: | |
621 | ret = blk_trace_remove(q); | |
622 | break; | |
623 | default: | |
624 | ret = -ENOTTY; | |
625 | break; | |
626 | } | |
627 | ||
628 | mutex_unlock(&bdev->bd_mutex); | |
629 | return ret; | |
630 | } | |
631 | ||
632 | /** | |
633 | * blk_trace_shutdown: - stop and cleanup trace structures | |
634 | * @q: the request queue associated with the device | |
635 | * | |
636 | **/ | |
165125e1 | 637 | void blk_trace_shutdown(struct request_queue *q) |
2056a782 | 638 | { |
6c5c9341 AD |
639 | if (q->blk_trace) { |
640 | blk_trace_startstop(q, 0); | |
641 | blk_trace_remove(q); | |
642 | } | |
2056a782 | 643 | } |
5f3ea37c ACM |
644 | |
645 | /* | |
646 | * blktrace probes | |
647 | */ | |
648 | ||
649 | /** | |
650 | * blk_add_trace_rq - Add a trace for a request oriented action | |
651 | * @q: queue the io is for | |
652 | * @rq: the source request | |
653 | * @what: the action | |
654 | * | |
655 | * Description: | |
656 | * Records an action against a request. Will log the bio offset + size. | |
657 | * | |
658 | **/ | |
659 | static void blk_add_trace_rq(struct request_queue *q, struct request *rq, | |
660 | u32 what) | |
661 | { | |
662 | struct blk_trace *bt = q->blk_trace; | |
663 | int rw = rq->cmd_flags & 0x03; | |
664 | ||
665 | if (likely(!bt)) | |
666 | return; | |
667 | ||
668 | if (blk_discard_rq(rq)) | |
669 | rw |= (1 << BIO_RW_DISCARD); | |
670 | ||
671 | if (blk_pc_request(rq)) { | |
672 | what |= BLK_TC_ACT(BLK_TC_PC); | |
2e46e8b2 TH |
673 | __blk_add_trace(bt, 0, blk_rq_bytes(rq), rw, |
674 | what, rq->errors, rq->cmd_len, rq->cmd); | |
5f3ea37c ACM |
675 | } else { |
676 | what |= BLK_TC_ACT(BLK_TC_FS); | |
2e46e8b2 TH |
677 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), rw, |
678 | what, rq->errors, 0, NULL); | |
5f3ea37c ACM |
679 | } |
680 | } | |
681 | ||
682 | static void blk_add_trace_rq_abort(struct request_queue *q, struct request *rq) | |
683 | { | |
684 | blk_add_trace_rq(q, rq, BLK_TA_ABORT); | |
685 | } | |
686 | ||
687 | static void blk_add_trace_rq_insert(struct request_queue *q, struct request *rq) | |
688 | { | |
689 | blk_add_trace_rq(q, rq, BLK_TA_INSERT); | |
690 | } | |
691 | ||
692 | static void blk_add_trace_rq_issue(struct request_queue *q, struct request *rq) | |
693 | { | |
694 | blk_add_trace_rq(q, rq, BLK_TA_ISSUE); | |
695 | } | |
696 | ||
939b3669 ACM |
697 | static void blk_add_trace_rq_requeue(struct request_queue *q, |
698 | struct request *rq) | |
5f3ea37c ACM |
699 | { |
700 | blk_add_trace_rq(q, rq, BLK_TA_REQUEUE); | |
701 | } | |
702 | ||
939b3669 ACM |
703 | static void blk_add_trace_rq_complete(struct request_queue *q, |
704 | struct request *rq) | |
5f3ea37c ACM |
705 | { |
706 | blk_add_trace_rq(q, rq, BLK_TA_COMPLETE); | |
707 | } | |
708 | ||
709 | /** | |
710 | * blk_add_trace_bio - Add a trace for a bio oriented action | |
711 | * @q: queue the io is for | |
712 | * @bio: the source bio | |
713 | * @what: the action | |
714 | * | |
715 | * Description: | |
716 | * Records an action against a bio. Will log the bio offset + size. | |
717 | * | |
718 | **/ | |
719 | static void blk_add_trace_bio(struct request_queue *q, struct bio *bio, | |
720 | u32 what) | |
721 | { | |
722 | struct blk_trace *bt = q->blk_trace; | |
723 | ||
724 | if (likely(!bt)) | |
725 | return; | |
726 | ||
727 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, | |
728 | !bio_flagged(bio, BIO_UPTODATE), 0, NULL); | |
729 | } | |
730 | ||
731 | static void blk_add_trace_bio_bounce(struct request_queue *q, struct bio *bio) | |
732 | { | |
733 | blk_add_trace_bio(q, bio, BLK_TA_BOUNCE); | |
734 | } | |
735 | ||
736 | static void blk_add_trace_bio_complete(struct request_queue *q, struct bio *bio) | |
737 | { | |
738 | blk_add_trace_bio(q, bio, BLK_TA_COMPLETE); | |
739 | } | |
740 | ||
939b3669 ACM |
741 | static void blk_add_trace_bio_backmerge(struct request_queue *q, |
742 | struct bio *bio) | |
5f3ea37c ACM |
743 | { |
744 | blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE); | |
745 | } | |
746 | ||
939b3669 ACM |
747 | static void blk_add_trace_bio_frontmerge(struct request_queue *q, |
748 | struct bio *bio) | |
5f3ea37c ACM |
749 | { |
750 | blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE); | |
751 | } | |
752 | ||
753 | static void blk_add_trace_bio_queue(struct request_queue *q, struct bio *bio) | |
754 | { | |
755 | blk_add_trace_bio(q, bio, BLK_TA_QUEUE); | |
756 | } | |
757 | ||
939b3669 ACM |
758 | static void blk_add_trace_getrq(struct request_queue *q, |
759 | struct bio *bio, int rw) | |
5f3ea37c ACM |
760 | { |
761 | if (bio) | |
762 | blk_add_trace_bio(q, bio, BLK_TA_GETRQ); | |
763 | else { | |
764 | struct blk_trace *bt = q->blk_trace; | |
765 | ||
766 | if (bt) | |
767 | __blk_add_trace(bt, 0, 0, rw, BLK_TA_GETRQ, 0, 0, NULL); | |
768 | } | |
769 | } | |
770 | ||
771 | ||
939b3669 ACM |
772 | static void blk_add_trace_sleeprq(struct request_queue *q, |
773 | struct bio *bio, int rw) | |
5f3ea37c ACM |
774 | { |
775 | if (bio) | |
776 | blk_add_trace_bio(q, bio, BLK_TA_SLEEPRQ); | |
777 | else { | |
778 | struct blk_trace *bt = q->blk_trace; | |
779 | ||
780 | if (bt) | |
939b3669 ACM |
781 | __blk_add_trace(bt, 0, 0, rw, BLK_TA_SLEEPRQ, |
782 | 0, 0, NULL); | |
5f3ea37c ACM |
783 | } |
784 | } | |
785 | ||
786 | static void blk_add_trace_plug(struct request_queue *q) | |
787 | { | |
788 | struct blk_trace *bt = q->blk_trace; | |
789 | ||
790 | if (bt) | |
791 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_PLUG, 0, 0, NULL); | |
792 | } | |
793 | ||
794 | static void blk_add_trace_unplug_io(struct request_queue *q) | |
795 | { | |
796 | struct blk_trace *bt = q->blk_trace; | |
797 | ||
798 | if (bt) { | |
799 | unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; | |
800 | __be64 rpdu = cpu_to_be64(pdu); | |
801 | ||
802 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_IO, 0, | |
803 | sizeof(rpdu), &rpdu); | |
804 | } | |
805 | } | |
806 | ||
807 | static void blk_add_trace_unplug_timer(struct request_queue *q) | |
808 | { | |
809 | struct blk_trace *bt = q->blk_trace; | |
810 | ||
811 | if (bt) { | |
812 | unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; | |
813 | __be64 rpdu = cpu_to_be64(pdu); | |
814 | ||
815 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_TIMER, 0, | |
816 | sizeof(rpdu), &rpdu); | |
817 | } | |
818 | } | |
819 | ||
820 | static void blk_add_trace_split(struct request_queue *q, struct bio *bio, | |
821 | unsigned int pdu) | |
822 | { | |
823 | struct blk_trace *bt = q->blk_trace; | |
824 | ||
825 | if (bt) { | |
826 | __be64 rpdu = cpu_to_be64(pdu); | |
827 | ||
828 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, | |
829 | BLK_TA_SPLIT, !bio_flagged(bio, BIO_UPTODATE), | |
830 | sizeof(rpdu), &rpdu); | |
831 | } | |
832 | } | |
833 | ||
834 | /** | |
835 | * blk_add_trace_remap - Add a trace for a remap operation | |
836 | * @q: queue the io is for | |
837 | * @bio: the source bio | |
838 | * @dev: target device | |
a42aaa3b | 839 | * @from: source sector |
5f3ea37c ACM |
840 | * |
841 | * Description: | |
842 | * Device mapper or raid target sometimes need to split a bio because | |
843 | * it spans a stripe (or similar). Add a trace for that action. | |
844 | * | |
845 | **/ | |
846 | static void blk_add_trace_remap(struct request_queue *q, struct bio *bio, | |
22a7c31a | 847 | dev_t dev, sector_t from) |
5f3ea37c ACM |
848 | { |
849 | struct blk_trace *bt = q->blk_trace; | |
850 | struct blk_io_trace_remap r; | |
851 | ||
852 | if (likely(!bt)) | |
853 | return; | |
854 | ||
a42aaa3b AB |
855 | r.device_from = cpu_to_be32(dev); |
856 | r.device_to = cpu_to_be32(bio->bi_bdev->bd_dev); | |
857 | r.sector_from = cpu_to_be64(from); | |
5f3ea37c | 858 | |
22a7c31a AB |
859 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, |
860 | BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), | |
861 | sizeof(r), &r); | |
5f3ea37c ACM |
862 | } |
863 | ||
864 | /** | |
865 | * blk_add_driver_data - Add binary message with driver-specific data | |
866 | * @q: queue the io is for | |
867 | * @rq: io request | |
868 | * @data: driver-specific data | |
869 | * @len: length of driver-specific data | |
870 | * | |
871 | * Description: | |
872 | * Some drivers might want to write driver-specific data per request. | |
873 | * | |
874 | **/ | |
875 | void blk_add_driver_data(struct request_queue *q, | |
876 | struct request *rq, | |
877 | void *data, size_t len) | |
878 | { | |
879 | struct blk_trace *bt = q->blk_trace; | |
880 | ||
881 | if (likely(!bt)) | |
882 | return; | |
883 | ||
884 | if (blk_pc_request(rq)) | |
2e46e8b2 TH |
885 | __blk_add_trace(bt, 0, blk_rq_bytes(rq), 0, |
886 | BLK_TA_DRV_DATA, rq->errors, len, data); | |
5f3ea37c | 887 | else |
2e46e8b2 TH |
888 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), 0, |
889 | BLK_TA_DRV_DATA, rq->errors, len, data); | |
5f3ea37c ACM |
890 | } |
891 | EXPORT_SYMBOL_GPL(blk_add_driver_data); | |
892 | ||
3c289ba7 | 893 | static void blk_register_tracepoints(void) |
5f3ea37c ACM |
894 | { |
895 | int ret; | |
896 | ||
897 | ret = register_trace_block_rq_abort(blk_add_trace_rq_abort); | |
898 | WARN_ON(ret); | |
899 | ret = register_trace_block_rq_insert(blk_add_trace_rq_insert); | |
900 | WARN_ON(ret); | |
901 | ret = register_trace_block_rq_issue(blk_add_trace_rq_issue); | |
902 | WARN_ON(ret); | |
903 | ret = register_trace_block_rq_requeue(blk_add_trace_rq_requeue); | |
904 | WARN_ON(ret); | |
905 | ret = register_trace_block_rq_complete(blk_add_trace_rq_complete); | |
906 | WARN_ON(ret); | |
907 | ret = register_trace_block_bio_bounce(blk_add_trace_bio_bounce); | |
908 | WARN_ON(ret); | |
909 | ret = register_trace_block_bio_complete(blk_add_trace_bio_complete); | |
910 | WARN_ON(ret); | |
911 | ret = register_trace_block_bio_backmerge(blk_add_trace_bio_backmerge); | |
912 | WARN_ON(ret); | |
913 | ret = register_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge); | |
914 | WARN_ON(ret); | |
915 | ret = register_trace_block_bio_queue(blk_add_trace_bio_queue); | |
916 | WARN_ON(ret); | |
917 | ret = register_trace_block_getrq(blk_add_trace_getrq); | |
918 | WARN_ON(ret); | |
919 | ret = register_trace_block_sleeprq(blk_add_trace_sleeprq); | |
920 | WARN_ON(ret); | |
921 | ret = register_trace_block_plug(blk_add_trace_plug); | |
922 | WARN_ON(ret); | |
923 | ret = register_trace_block_unplug_timer(blk_add_trace_unplug_timer); | |
924 | WARN_ON(ret); | |
925 | ret = register_trace_block_unplug_io(blk_add_trace_unplug_io); | |
926 | WARN_ON(ret); | |
927 | ret = register_trace_block_split(blk_add_trace_split); | |
928 | WARN_ON(ret); | |
929 | ret = register_trace_block_remap(blk_add_trace_remap); | |
930 | WARN_ON(ret); | |
5f3ea37c ACM |
931 | } |
932 | ||
933 | static void blk_unregister_tracepoints(void) | |
934 | { | |
935 | unregister_trace_block_remap(blk_add_trace_remap); | |
936 | unregister_trace_block_split(blk_add_trace_split); | |
937 | unregister_trace_block_unplug_io(blk_add_trace_unplug_io); | |
938 | unregister_trace_block_unplug_timer(blk_add_trace_unplug_timer); | |
939 | unregister_trace_block_plug(blk_add_trace_plug); | |
940 | unregister_trace_block_sleeprq(blk_add_trace_sleeprq); | |
941 | unregister_trace_block_getrq(blk_add_trace_getrq); | |
942 | unregister_trace_block_bio_queue(blk_add_trace_bio_queue); | |
943 | unregister_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge); | |
944 | unregister_trace_block_bio_backmerge(blk_add_trace_bio_backmerge); | |
945 | unregister_trace_block_bio_complete(blk_add_trace_bio_complete); | |
946 | unregister_trace_block_bio_bounce(blk_add_trace_bio_bounce); | |
947 | unregister_trace_block_rq_complete(blk_add_trace_rq_complete); | |
948 | unregister_trace_block_rq_requeue(blk_add_trace_rq_requeue); | |
949 | unregister_trace_block_rq_issue(blk_add_trace_rq_issue); | |
950 | unregister_trace_block_rq_insert(blk_add_trace_rq_insert); | |
951 | unregister_trace_block_rq_abort(blk_add_trace_rq_abort); | |
952 | ||
953 | tracepoint_synchronize_unregister(); | |
954 | } | |
c71a8961 ACM |
955 | |
956 | /* | |
957 | * struct blk_io_tracer formatting routines | |
958 | */ | |
959 | ||
960 | static void fill_rwbs(char *rwbs, const struct blk_io_trace *t) | |
961 | { | |
157f9c00 | 962 | int i = 0; |
65796348 | 963 | int tc = t->action >> BLK_TC_SHIFT; |
157f9c00 | 964 | |
18cea459 LZ |
965 | if (t->action == BLK_TN_MESSAGE) { |
966 | rwbs[i++] = 'N'; | |
967 | goto out; | |
968 | } | |
969 | ||
65796348 | 970 | if (tc & BLK_TC_DISCARD) |
157f9c00 | 971 | rwbs[i++] = 'D'; |
65796348 | 972 | else if (tc & BLK_TC_WRITE) |
157f9c00 ACM |
973 | rwbs[i++] = 'W'; |
974 | else if (t->bytes) | |
975 | rwbs[i++] = 'R'; | |
976 | else | |
977 | rwbs[i++] = 'N'; | |
978 | ||
65796348 | 979 | if (tc & BLK_TC_AHEAD) |
157f9c00 | 980 | rwbs[i++] = 'A'; |
65796348 | 981 | if (tc & BLK_TC_BARRIER) |
157f9c00 | 982 | rwbs[i++] = 'B'; |
65796348 | 983 | if (tc & BLK_TC_SYNC) |
157f9c00 | 984 | rwbs[i++] = 'S'; |
65796348 | 985 | if (tc & BLK_TC_META) |
157f9c00 | 986 | rwbs[i++] = 'M'; |
18cea459 | 987 | out: |
157f9c00 | 988 | rwbs[i] = '\0'; |
c71a8961 ACM |
989 | } |
990 | ||
991 | static inline | |
992 | const struct blk_io_trace *te_blk_io_trace(const struct trace_entry *ent) | |
993 | { | |
994 | return (const struct blk_io_trace *)ent; | |
995 | } | |
996 | ||
997 | static inline const void *pdu_start(const struct trace_entry *ent) | |
998 | { | |
999 | return te_blk_io_trace(ent) + 1; | |
1000 | } | |
1001 | ||
66de7792 LZ |
1002 | static inline u32 t_action(const struct trace_entry *ent) |
1003 | { | |
1004 | return te_blk_io_trace(ent)->action; | |
1005 | } | |
1006 | ||
1007 | static inline u32 t_bytes(const struct trace_entry *ent) | |
1008 | { | |
1009 | return te_blk_io_trace(ent)->bytes; | |
1010 | } | |
1011 | ||
c71a8961 ACM |
1012 | static inline u32 t_sec(const struct trace_entry *ent) |
1013 | { | |
1014 | return te_blk_io_trace(ent)->bytes >> 9; | |
1015 | } | |
1016 | ||
1017 | static inline unsigned long long t_sector(const struct trace_entry *ent) | |
1018 | { | |
1019 | return te_blk_io_trace(ent)->sector; | |
1020 | } | |
1021 | ||
1022 | static inline __u16 t_error(const struct trace_entry *ent) | |
1023 | { | |
e0dc81be | 1024 | return te_blk_io_trace(ent)->error; |
c71a8961 ACM |
1025 | } |
1026 | ||
1027 | static __u64 get_pdu_int(const struct trace_entry *ent) | |
1028 | { | |
1029 | const __u64 *val = pdu_start(ent); | |
1030 | return be64_to_cpu(*val); | |
1031 | } | |
1032 | ||
1033 | static void get_pdu_remap(const struct trace_entry *ent, | |
1034 | struct blk_io_trace_remap *r) | |
1035 | { | |
1036 | const struct blk_io_trace_remap *__r = pdu_start(ent); | |
a42aaa3b | 1037 | __u64 sector_from = __r->sector_from; |
c71a8961 | 1038 | |
c71a8961 | 1039 | r->device_from = be32_to_cpu(__r->device_from); |
a42aaa3b AB |
1040 | r->device_to = be32_to_cpu(__r->device_to); |
1041 | r->sector_from = be64_to_cpu(sector_from); | |
c71a8961 ACM |
1042 | } |
1043 | ||
b6a4b0c3 LZ |
1044 | typedef int (blk_log_action_t) (struct trace_iterator *iter, const char *act); |
1045 | ||
1046 | static int blk_log_action_classic(struct trace_iterator *iter, const char *act) | |
c71a8961 ACM |
1047 | { |
1048 | char rwbs[6]; | |
35ac51bf LZ |
1049 | unsigned long long ts = iter->ts; |
1050 | unsigned long nsec_rem = do_div(ts, NSEC_PER_SEC); | |
c71a8961 | 1051 | unsigned secs = (unsigned long)ts; |
b6a4b0c3 | 1052 | const struct blk_io_trace *t = te_blk_io_trace(iter->ent); |
c71a8961 ACM |
1053 | |
1054 | fill_rwbs(rwbs, t); | |
1055 | ||
1056 | return trace_seq_printf(&iter->seq, | |
35ac51bf | 1057 | "%3d,%-3d %2d %5d.%09lu %5u %2s %3s ", |
c71a8961 | 1058 | MAJOR(t->device), MINOR(t->device), iter->cpu, |
b6a4b0c3 | 1059 | secs, nsec_rem, iter->ent->pid, act, rwbs); |
c71a8961 ACM |
1060 | } |
1061 | ||
b6a4b0c3 | 1062 | static int blk_log_action(struct trace_iterator *iter, const char *act) |
c71a8961 ACM |
1063 | { |
1064 | char rwbs[6]; | |
b6a4b0c3 LZ |
1065 | const struct blk_io_trace *t = te_blk_io_trace(iter->ent); |
1066 | ||
c71a8961 | 1067 | fill_rwbs(rwbs, t); |
b6a4b0c3 | 1068 | return trace_seq_printf(&iter->seq, "%3d,%-3d %2s %3s ", |
c71a8961 ACM |
1069 | MAJOR(t->device), MINOR(t->device), act, rwbs); |
1070 | } | |
1071 | ||
66de7792 LZ |
1072 | static int blk_log_dump_pdu(struct trace_seq *s, const struct trace_entry *ent) |
1073 | { | |
04986257 | 1074 | const unsigned char *pdu_buf; |
66de7792 LZ |
1075 | int pdu_len; |
1076 | int i, end, ret; | |
1077 | ||
1078 | pdu_buf = pdu_start(ent); | |
1079 | pdu_len = te_blk_io_trace(ent)->pdu_len; | |
1080 | ||
1081 | if (!pdu_len) | |
1082 | return 1; | |
1083 | ||
1084 | /* find the last zero that needs to be printed */ | |
1085 | for (end = pdu_len - 1; end >= 0; end--) | |
1086 | if (pdu_buf[end]) | |
1087 | break; | |
1088 | end++; | |
1089 | ||
1090 | if (!trace_seq_putc(s, '(')) | |
1091 | return 0; | |
1092 | ||
1093 | for (i = 0; i < pdu_len; i++) { | |
1094 | ||
1095 | ret = trace_seq_printf(s, "%s%02x", | |
1096 | i == 0 ? "" : " ", pdu_buf[i]); | |
1097 | if (!ret) | |
1098 | return ret; | |
1099 | ||
1100 | /* | |
1101 | * stop when the rest is just zeroes and indicate so | |
1102 | * with a ".." appended | |
1103 | */ | |
1104 | if (i == end && end != pdu_len - 1) | |
1105 | return trace_seq_puts(s, " ..) "); | |
1106 | } | |
1107 | ||
1108 | return trace_seq_puts(s, ") "); | |
1109 | } | |
1110 | ||
c71a8961 ACM |
1111 | static int blk_log_generic(struct trace_seq *s, const struct trace_entry *ent) |
1112 | { | |
4ca53085 SR |
1113 | char cmd[TASK_COMM_LEN]; |
1114 | ||
1115 | trace_find_cmdline(ent->pid, cmd); | |
c71a8961 | 1116 | |
66de7792 LZ |
1117 | if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { |
1118 | int ret; | |
1119 | ||
1120 | ret = trace_seq_printf(s, "%u ", t_bytes(ent)); | |
1121 | if (!ret) | |
1122 | return 0; | |
1123 | ret = blk_log_dump_pdu(s, ent); | |
1124 | if (!ret) | |
1125 | return 0; | |
1126 | return trace_seq_printf(s, "[%s]\n", cmd); | |
1127 | } else { | |
1128 | if (t_sec(ent)) | |
1129 | return trace_seq_printf(s, "%llu + %u [%s]\n", | |
1130 | t_sector(ent), t_sec(ent), cmd); | |
1131 | return trace_seq_printf(s, "[%s]\n", cmd); | |
1132 | } | |
c71a8961 ACM |
1133 | } |
1134 | ||
157f9c00 ACM |
1135 | static int blk_log_with_error(struct trace_seq *s, |
1136 | const struct trace_entry *ent) | |
c71a8961 | 1137 | { |
66de7792 LZ |
1138 | if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { |
1139 | int ret; | |
1140 | ||
1141 | ret = blk_log_dump_pdu(s, ent); | |
1142 | if (ret) | |
1143 | return trace_seq_printf(s, "[%d]\n", t_error(ent)); | |
1144 | return 0; | |
1145 | } else { | |
1146 | if (t_sec(ent)) | |
1147 | return trace_seq_printf(s, "%llu + %u [%d]\n", | |
1148 | t_sector(ent), | |
1149 | t_sec(ent), t_error(ent)); | |
1150 | return trace_seq_printf(s, "%llu [%d]\n", | |
1151 | t_sector(ent), t_error(ent)); | |
1152 | } | |
c71a8961 ACM |
1153 | } |
1154 | ||
1155 | static int blk_log_remap(struct trace_seq *s, const struct trace_entry *ent) | |
1156 | { | |
a42aaa3b | 1157 | struct blk_io_trace_remap r = { .device_from = 0, }; |
c71a8961 ACM |
1158 | |
1159 | get_pdu_remap(ent, &r); | |
1160 | return trace_seq_printf(s, "%llu + %u <- (%d,%d) %llu\n", | |
a42aaa3b AB |
1161 | t_sector(ent), t_sec(ent), |
1162 | MAJOR(r.device_from), MINOR(r.device_from), | |
1163 | (unsigned long long)r.sector_from); | |
c71a8961 ACM |
1164 | } |
1165 | ||
1166 | static int blk_log_plug(struct trace_seq *s, const struct trace_entry *ent) | |
1167 | { | |
4ca53085 SR |
1168 | char cmd[TASK_COMM_LEN]; |
1169 | ||
1170 | trace_find_cmdline(ent->pid, cmd); | |
1171 | ||
1172 | return trace_seq_printf(s, "[%s]\n", cmd); | |
c71a8961 ACM |
1173 | } |
1174 | ||
1175 | static int blk_log_unplug(struct trace_seq *s, const struct trace_entry *ent) | |
1176 | { | |
4ca53085 SR |
1177 | char cmd[TASK_COMM_LEN]; |
1178 | ||
1179 | trace_find_cmdline(ent->pid, cmd); | |
1180 | ||
1181 | return trace_seq_printf(s, "[%s] %llu\n", cmd, get_pdu_int(ent)); | |
c71a8961 ACM |
1182 | } |
1183 | ||
1184 | static int blk_log_split(struct trace_seq *s, const struct trace_entry *ent) | |
1185 | { | |
4ca53085 SR |
1186 | char cmd[TASK_COMM_LEN]; |
1187 | ||
1188 | trace_find_cmdline(ent->pid, cmd); | |
1189 | ||
c71a8961 | 1190 | return trace_seq_printf(s, "%llu / %llu [%s]\n", t_sector(ent), |
4ca53085 | 1191 | get_pdu_int(ent), cmd); |
c71a8961 ACM |
1192 | } |
1193 | ||
18cea459 LZ |
1194 | static int blk_log_msg(struct trace_seq *s, const struct trace_entry *ent) |
1195 | { | |
1196 | int ret; | |
1197 | const struct blk_io_trace *t = te_blk_io_trace(ent); | |
1198 | ||
1199 | ret = trace_seq_putmem(s, t + 1, t->pdu_len); | |
1200 | if (ret) | |
1201 | return trace_seq_putc(s, '\n'); | |
1202 | return ret; | |
1203 | } | |
1204 | ||
c71a8961 ACM |
1205 | /* |
1206 | * struct tracer operations | |
1207 | */ | |
1208 | ||
1209 | static void blk_tracer_print_header(struct seq_file *m) | |
1210 | { | |
1211 | if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) | |
1212 | return; | |
1213 | seq_puts(m, "# DEV CPU TIMESTAMP PID ACT FLG\n" | |
1214 | "# | | | | | |\n"); | |
1215 | } | |
1216 | ||
1217 | static void blk_tracer_start(struct trace_array *tr) | |
1218 | { | |
ad5dd549 | 1219 | blk_tracer_enabled = true; |
c71a8961 ACM |
1220 | } |
1221 | ||
1222 | static int blk_tracer_init(struct trace_array *tr) | |
1223 | { | |
1224 | blk_tr = tr; | |
1225 | blk_tracer_start(tr); | |
c71a8961 ACM |
1226 | return 0; |
1227 | } | |
1228 | ||
1229 | static void blk_tracer_stop(struct trace_array *tr) | |
1230 | { | |
ad5dd549 | 1231 | blk_tracer_enabled = false; |
c71a8961 ACM |
1232 | } |
1233 | ||
1234 | static void blk_tracer_reset(struct trace_array *tr) | |
1235 | { | |
c71a8961 ACM |
1236 | blk_tracer_stop(tr); |
1237 | } | |
1238 | ||
e4955c99 | 1239 | static const struct { |
c71a8961 | 1240 | const char *act[2]; |
ef18012b | 1241 | int (*print)(struct trace_seq *s, const struct trace_entry *ent); |
e4955c99 | 1242 | } what2act[] = { |
ef18012b | 1243 | [__BLK_TA_QUEUE] = {{ "Q", "queue" }, blk_log_generic }, |
c71a8961 ACM |
1244 | [__BLK_TA_BACKMERGE] = {{ "M", "backmerge" }, blk_log_generic }, |
1245 | [__BLK_TA_FRONTMERGE] = {{ "F", "frontmerge" }, blk_log_generic }, | |
1246 | [__BLK_TA_GETRQ] = {{ "G", "getrq" }, blk_log_generic }, | |
1247 | [__BLK_TA_SLEEPRQ] = {{ "S", "sleeprq" }, blk_log_generic }, | |
1248 | [__BLK_TA_REQUEUE] = {{ "R", "requeue" }, blk_log_with_error }, | |
1249 | [__BLK_TA_ISSUE] = {{ "D", "issue" }, blk_log_generic }, | |
1250 | [__BLK_TA_COMPLETE] = {{ "C", "complete" }, blk_log_with_error }, | |
1251 | [__BLK_TA_PLUG] = {{ "P", "plug" }, blk_log_plug }, | |
1252 | [__BLK_TA_UNPLUG_IO] = {{ "U", "unplug_io" }, blk_log_unplug }, | |
1253 | [__BLK_TA_UNPLUG_TIMER] = {{ "UT", "unplug_timer" }, blk_log_unplug }, | |
1254 | [__BLK_TA_INSERT] = {{ "I", "insert" }, blk_log_generic }, | |
1255 | [__BLK_TA_SPLIT] = {{ "X", "split" }, blk_log_split }, | |
1256 | [__BLK_TA_BOUNCE] = {{ "B", "bounce" }, blk_log_generic }, | |
1257 | [__BLK_TA_REMAP] = {{ "A", "remap" }, blk_log_remap }, | |
1258 | }; | |
1259 | ||
b6a4b0c3 LZ |
1260 | static enum print_line_t print_one_line(struct trace_iterator *iter, |
1261 | bool classic) | |
c71a8961 | 1262 | { |
2c9b238e | 1263 | struct trace_seq *s = &iter->seq; |
b6a4b0c3 LZ |
1264 | const struct blk_io_trace *t; |
1265 | u16 what; | |
c71a8961 | 1266 | int ret; |
b6a4b0c3 LZ |
1267 | bool long_act; |
1268 | blk_log_action_t *log_action; | |
c71a8961 | 1269 | |
b6a4b0c3 LZ |
1270 | t = te_blk_io_trace(iter->ent); |
1271 | what = t->action & ((1 << BLK_TC_SHIFT) - 1); | |
1272 | long_act = !!(trace_flags & TRACE_ITER_VERBOSE); | |
1273 | log_action = classic ? &blk_log_action_classic : &blk_log_action; | |
08a06b83 | 1274 | |
18cea459 LZ |
1275 | if (t->action == BLK_TN_MESSAGE) { |
1276 | ret = log_action(iter, long_act ? "message" : "m"); | |
1277 | if (ret) | |
1278 | ret = blk_log_msg(s, iter->ent); | |
1279 | goto out; | |
1280 | } | |
1281 | ||
eb08f8eb | 1282 | if (unlikely(what == 0 || what >= ARRAY_SIZE(what2act))) |
b78825d6 | 1283 | ret = trace_seq_printf(s, "Unknown action %x\n", what); |
c71a8961 | 1284 | else { |
b6a4b0c3 | 1285 | ret = log_action(iter, what2act[what].act[long_act]); |
c71a8961 | 1286 | if (ret) |
2c9b238e | 1287 | ret = what2act[what].print(s, iter->ent); |
c71a8961 | 1288 | } |
18cea459 | 1289 | out: |
c71a8961 ACM |
1290 | return ret ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; |
1291 | } | |
1292 | ||
b6a4b0c3 LZ |
1293 | static enum print_line_t blk_trace_event_print(struct trace_iterator *iter, |
1294 | int flags) | |
1295 | { | |
b6a4b0c3 LZ |
1296 | return print_one_line(iter, false); |
1297 | } | |
1298 | ||
08a06b83 ACM |
1299 | static int blk_trace_synthesize_old_trace(struct trace_iterator *iter) |
1300 | { | |
1301 | struct trace_seq *s = &iter->seq; | |
1302 | struct blk_io_trace *t = (struct blk_io_trace *)iter->ent; | |
1303 | const int offset = offsetof(struct blk_io_trace, sector); | |
1304 | struct blk_io_trace old = { | |
1305 | .magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION, | |
6c051ce0 | 1306 | .time = iter->ts, |
08a06b83 ACM |
1307 | }; |
1308 | ||
1309 | if (!trace_seq_putmem(s, &old, offset)) | |
1310 | return 0; | |
1311 | return trace_seq_putmem(s, &t->sector, | |
1312 | sizeof(old) - offset + t->pdu_len); | |
1313 | } | |
1314 | ||
ae7462b4 ACM |
1315 | static enum print_line_t |
1316 | blk_trace_event_print_binary(struct trace_iterator *iter, int flags) | |
08a06b83 ACM |
1317 | { |
1318 | return blk_trace_synthesize_old_trace(iter) ? | |
1319 | TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; | |
1320 | } | |
1321 | ||
c71a8961 ACM |
1322 | static enum print_line_t blk_tracer_print_line(struct trace_iterator *iter) |
1323 | { | |
c71a8961 ACM |
1324 | if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) |
1325 | return TRACE_TYPE_UNHANDLED; | |
1326 | ||
b6a4b0c3 | 1327 | return print_one_line(iter, true); |
c71a8961 ACM |
1328 | } |
1329 | ||
f3948f88 LZ |
1330 | static int blk_tracer_set_flag(u32 old_flags, u32 bit, int set) |
1331 | { | |
1332 | /* don't output context-info for blk_classic output */ | |
1333 | if (bit == TRACE_BLK_OPT_CLASSIC) { | |
1334 | if (set) | |
1335 | trace_flags &= ~TRACE_ITER_CONTEXT_INFO; | |
1336 | else | |
1337 | trace_flags |= TRACE_ITER_CONTEXT_INFO; | |
1338 | } | |
1339 | return 0; | |
1340 | } | |
1341 | ||
c71a8961 ACM |
1342 | static struct tracer blk_tracer __read_mostly = { |
1343 | .name = "blk", | |
1344 | .init = blk_tracer_init, | |
1345 | .reset = blk_tracer_reset, | |
1346 | .start = blk_tracer_start, | |
1347 | .stop = blk_tracer_stop, | |
1348 | .print_header = blk_tracer_print_header, | |
1349 | .print_line = blk_tracer_print_line, | |
1350 | .flags = &blk_tracer_flags, | |
f3948f88 | 1351 | .set_flag = blk_tracer_set_flag, |
c71a8961 ACM |
1352 | }; |
1353 | ||
1354 | static struct trace_event trace_blk_event = { | |
ef18012b | 1355 | .type = TRACE_BLK, |
c71a8961 | 1356 | .trace = blk_trace_event_print, |
08a06b83 | 1357 | .binary = blk_trace_event_print_binary, |
c71a8961 ACM |
1358 | }; |
1359 | ||
1360 | static int __init init_blk_tracer(void) | |
1361 | { | |
1362 | if (!register_ftrace_event(&trace_blk_event)) { | |
1363 | pr_warning("Warning: could not register block events\n"); | |
1364 | return 1; | |
1365 | } | |
1366 | ||
1367 | if (register_tracer(&blk_tracer) != 0) { | |
1368 | pr_warning("Warning: could not register the block tracer\n"); | |
1369 | unregister_ftrace_event(&trace_blk_event); | |
1370 | return 1; | |
1371 | } | |
1372 | ||
1373 | return 0; | |
1374 | } | |
1375 | ||
1376 | device_initcall(init_blk_tracer); | |
1377 | ||
1378 | static int blk_trace_remove_queue(struct request_queue *q) | |
1379 | { | |
1380 | struct blk_trace *bt; | |
1381 | ||
1382 | bt = xchg(&q->blk_trace, NULL); | |
1383 | if (bt == NULL) | |
1384 | return -EINVAL; | |
1385 | ||
17ba97e3 LZ |
1386 | if (atomic_dec_and_test(&blk_probes_ref)) |
1387 | blk_unregister_tracepoints(); | |
1388 | ||
ad5dd549 | 1389 | blk_trace_free(bt); |
c71a8961 ACM |
1390 | return 0; |
1391 | } | |
1392 | ||
1393 | /* | |
1394 | * Setup everything required to start tracing | |
1395 | */ | |
9908c309 LZ |
1396 | static int blk_trace_setup_queue(struct request_queue *q, |
1397 | struct block_device *bdev) | |
c71a8961 ACM |
1398 | { |
1399 | struct blk_trace *old_bt, *bt = NULL; | |
18cea459 | 1400 | int ret = -ENOMEM; |
c71a8961 | 1401 | |
c71a8961 ACM |
1402 | bt = kzalloc(sizeof(*bt), GFP_KERNEL); |
1403 | if (!bt) | |
15152e44 | 1404 | return -ENOMEM; |
c71a8961 | 1405 | |
18cea459 LZ |
1406 | bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); |
1407 | if (!bt->msg_data) | |
1408 | goto free_bt; | |
1409 | ||
9908c309 | 1410 | bt->dev = bdev->bd_dev; |
c71a8961 | 1411 | bt->act_mask = (u16)-1; |
9908c309 LZ |
1412 | |
1413 | blk_trace_setup_lba(bt, bdev); | |
c71a8961 ACM |
1414 | |
1415 | old_bt = xchg(&q->blk_trace, bt); | |
1416 | if (old_bt != NULL) { | |
1417 | (void)xchg(&q->blk_trace, old_bt); | |
18cea459 LZ |
1418 | ret = -EBUSY; |
1419 | goto free_bt; | |
c71a8961 | 1420 | } |
15152e44 | 1421 | |
17ba97e3 LZ |
1422 | if (atomic_inc_return(&blk_probes_ref) == 1) |
1423 | blk_register_tracepoints(); | |
c71a8961 | 1424 | return 0; |
18cea459 LZ |
1425 | |
1426 | free_bt: | |
1427 | blk_trace_free(bt); | |
1428 | return ret; | |
c71a8961 ACM |
1429 | } |
1430 | ||
1431 | /* | |
1432 | * sysfs interface to enable and configure tracing | |
1433 | */ | |
1434 | ||
c71a8961 ACM |
1435 | static ssize_t sysfs_blk_trace_attr_show(struct device *dev, |
1436 | struct device_attribute *attr, | |
1437 | char *buf); | |
1438 | static ssize_t sysfs_blk_trace_attr_store(struct device *dev, | |
1439 | struct device_attribute *attr, | |
1440 | const char *buf, size_t count); | |
1441 | #define BLK_TRACE_DEVICE_ATTR(_name) \ | |
1442 | DEVICE_ATTR(_name, S_IRUGO | S_IWUSR, \ | |
1443 | sysfs_blk_trace_attr_show, \ | |
1444 | sysfs_blk_trace_attr_store) | |
1445 | ||
cd649b8b | 1446 | static BLK_TRACE_DEVICE_ATTR(enable); |
c71a8961 ACM |
1447 | static BLK_TRACE_DEVICE_ATTR(act_mask); |
1448 | static BLK_TRACE_DEVICE_ATTR(pid); | |
1449 | static BLK_TRACE_DEVICE_ATTR(start_lba); | |
1450 | static BLK_TRACE_DEVICE_ATTR(end_lba); | |
1451 | ||
1452 | static struct attribute *blk_trace_attrs[] = { | |
1453 | &dev_attr_enable.attr, | |
1454 | &dev_attr_act_mask.attr, | |
1455 | &dev_attr_pid.attr, | |
1456 | &dev_attr_start_lba.attr, | |
1457 | &dev_attr_end_lba.attr, | |
1458 | NULL | |
1459 | }; | |
1460 | ||
1461 | struct attribute_group blk_trace_attr_group = { | |
1462 | .name = "trace", | |
1463 | .attrs = blk_trace_attrs, | |
1464 | }; | |
1465 | ||
09341997 LZ |
1466 | static const struct { |
1467 | int mask; | |
1468 | const char *str; | |
1469 | } mask_maps[] = { | |
1470 | { BLK_TC_READ, "read" }, | |
1471 | { BLK_TC_WRITE, "write" }, | |
1472 | { BLK_TC_BARRIER, "barrier" }, | |
1473 | { BLK_TC_SYNC, "sync" }, | |
1474 | { BLK_TC_QUEUE, "queue" }, | |
1475 | { BLK_TC_REQUEUE, "requeue" }, | |
1476 | { BLK_TC_ISSUE, "issue" }, | |
1477 | { BLK_TC_COMPLETE, "complete" }, | |
1478 | { BLK_TC_FS, "fs" }, | |
1479 | { BLK_TC_PC, "pc" }, | |
1480 | { BLK_TC_AHEAD, "ahead" }, | |
1481 | { BLK_TC_META, "meta" }, | |
1482 | { BLK_TC_DISCARD, "discard" }, | |
1483 | { BLK_TC_DRV_DATA, "drv_data" }, | |
1484 | }; | |
1485 | ||
1486 | static int blk_trace_str2mask(const char *str) | |
c71a8961 | 1487 | { |
09341997 | 1488 | int i; |
c71a8961 | 1489 | int mask = 0; |
9eb85125 | 1490 | char *buf, *s, *token; |
c71a8961 | 1491 | |
9eb85125 LZ |
1492 | buf = kstrdup(str, GFP_KERNEL); |
1493 | if (buf == NULL) | |
c71a8961 | 1494 | return -ENOMEM; |
9eb85125 | 1495 | s = strstrip(buf); |
c71a8961 ACM |
1496 | |
1497 | while (1) { | |
09341997 LZ |
1498 | token = strsep(&s, ","); |
1499 | if (token == NULL) | |
c71a8961 ACM |
1500 | break; |
1501 | ||
09341997 LZ |
1502 | if (*token == '\0') |
1503 | continue; | |
1504 | ||
1505 | for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { | |
1506 | if (strcasecmp(token, mask_maps[i].str) == 0) { | |
1507 | mask |= mask_maps[i].mask; | |
1508 | break; | |
1509 | } | |
1510 | } | |
1511 | if (i == ARRAY_SIZE(mask_maps)) { | |
1512 | mask = -EINVAL; | |
1513 | break; | |
1514 | } | |
c71a8961 | 1515 | } |
9eb85125 | 1516 | kfree(buf); |
c71a8961 ACM |
1517 | |
1518 | return mask; | |
1519 | } | |
1520 | ||
09341997 LZ |
1521 | static ssize_t blk_trace_mask2str(char *buf, int mask) |
1522 | { | |
1523 | int i; | |
1524 | char *p = buf; | |
1525 | ||
1526 | for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { | |
1527 | if (mask & mask_maps[i].mask) { | |
1528 | p += sprintf(p, "%s%s", | |
1529 | (p == buf) ? "" : ",", mask_maps[i].str); | |
1530 | } | |
1531 | } | |
1532 | *p++ = '\n'; | |
1533 | ||
1534 | return p - buf; | |
1535 | } | |
1536 | ||
b125130b LZ |
1537 | static struct request_queue *blk_trace_get_queue(struct block_device *bdev) |
1538 | { | |
1539 | if (bdev->bd_disk == NULL) | |
1540 | return NULL; | |
1541 | ||
1542 | return bdev_get_queue(bdev); | |
1543 | } | |
1544 | ||
c71a8961 ACM |
1545 | static ssize_t sysfs_blk_trace_attr_show(struct device *dev, |
1546 | struct device_attribute *attr, | |
1547 | char *buf) | |
1548 | { | |
1549 | struct hd_struct *p = dev_to_part(dev); | |
1550 | struct request_queue *q; | |
1551 | struct block_device *bdev; | |
1552 | ssize_t ret = -ENXIO; | |
1553 | ||
1554 | lock_kernel(); | |
1555 | bdev = bdget(part_devt(p)); | |
1556 | if (bdev == NULL) | |
1557 | goto out_unlock_kernel; | |
1558 | ||
b125130b | 1559 | q = blk_trace_get_queue(bdev); |
c71a8961 ACM |
1560 | if (q == NULL) |
1561 | goto out_bdput; | |
b125130b | 1562 | |
c71a8961 | 1563 | mutex_lock(&bdev->bd_mutex); |
cd649b8b LZ |
1564 | |
1565 | if (attr == &dev_attr_enable) { | |
1566 | ret = sprintf(buf, "%u\n", !!q->blk_trace); | |
1567 | goto out_unlock_bdev; | |
1568 | } | |
1569 | ||
c71a8961 ACM |
1570 | if (q->blk_trace == NULL) |
1571 | ret = sprintf(buf, "disabled\n"); | |
1572 | else if (attr == &dev_attr_act_mask) | |
09341997 | 1573 | ret = blk_trace_mask2str(buf, q->blk_trace->act_mask); |
c71a8961 ACM |
1574 | else if (attr == &dev_attr_pid) |
1575 | ret = sprintf(buf, "%u\n", q->blk_trace->pid); | |
1576 | else if (attr == &dev_attr_start_lba) | |
1577 | ret = sprintf(buf, "%llu\n", q->blk_trace->start_lba); | |
1578 | else if (attr == &dev_attr_end_lba) | |
1579 | ret = sprintf(buf, "%llu\n", q->blk_trace->end_lba); | |
cd649b8b LZ |
1580 | |
1581 | out_unlock_bdev: | |
c71a8961 ACM |
1582 | mutex_unlock(&bdev->bd_mutex); |
1583 | out_bdput: | |
1584 | bdput(bdev); | |
1585 | out_unlock_kernel: | |
1586 | unlock_kernel(); | |
1587 | return ret; | |
1588 | } | |
1589 | ||
1590 | static ssize_t sysfs_blk_trace_attr_store(struct device *dev, | |
1591 | struct device_attribute *attr, | |
1592 | const char *buf, size_t count) | |
1593 | { | |
1594 | struct block_device *bdev; | |
1595 | struct request_queue *q; | |
1596 | struct hd_struct *p; | |
1597 | u64 value; | |
09341997 | 1598 | ssize_t ret = -EINVAL; |
c71a8961 ACM |
1599 | |
1600 | if (count == 0) | |
1601 | goto out; | |
1602 | ||
1603 | if (attr == &dev_attr_act_mask) { | |
1604 | if (sscanf(buf, "%llx", &value) != 1) { | |
1605 | /* Assume it is a list of trace category names */ | |
09341997 LZ |
1606 | ret = blk_trace_str2mask(buf); |
1607 | if (ret < 0) | |
c71a8961 | 1608 | goto out; |
09341997 | 1609 | value = ret; |
c71a8961 ACM |
1610 | } |
1611 | } else if (sscanf(buf, "%llu", &value) != 1) | |
1612 | goto out; | |
1613 | ||
09341997 LZ |
1614 | ret = -ENXIO; |
1615 | ||
c71a8961 ACM |
1616 | lock_kernel(); |
1617 | p = dev_to_part(dev); | |
1618 | bdev = bdget(part_devt(p)); | |
1619 | if (bdev == NULL) | |
1620 | goto out_unlock_kernel; | |
1621 | ||
b125130b | 1622 | q = blk_trace_get_queue(bdev); |
c71a8961 ACM |
1623 | if (q == NULL) |
1624 | goto out_bdput; | |
1625 | ||
1626 | mutex_lock(&bdev->bd_mutex); | |
cd649b8b LZ |
1627 | |
1628 | if (attr == &dev_attr_enable) { | |
1629 | if (value) | |
9908c309 | 1630 | ret = blk_trace_setup_queue(q, bdev); |
cd649b8b LZ |
1631 | else |
1632 | ret = blk_trace_remove_queue(q); | |
1633 | goto out_unlock_bdev; | |
1634 | } | |
1635 | ||
c71a8961 ACM |
1636 | ret = 0; |
1637 | if (q->blk_trace == NULL) | |
9908c309 | 1638 | ret = blk_trace_setup_queue(q, bdev); |
c71a8961 ACM |
1639 | |
1640 | if (ret == 0) { | |
1641 | if (attr == &dev_attr_act_mask) | |
1642 | q->blk_trace->act_mask = value; | |
1643 | else if (attr == &dev_attr_pid) | |
1644 | q->blk_trace->pid = value; | |
1645 | else if (attr == &dev_attr_start_lba) | |
1646 | q->blk_trace->start_lba = value; | |
1647 | else if (attr == &dev_attr_end_lba) | |
1648 | q->blk_trace->end_lba = value; | |
c71a8961 | 1649 | } |
cd649b8b LZ |
1650 | |
1651 | out_unlock_bdev: | |
c71a8961 ACM |
1652 | mutex_unlock(&bdev->bd_mutex); |
1653 | out_bdput: | |
1654 | bdput(bdev); | |
1655 | out_unlock_kernel: | |
1656 | unlock_kernel(); | |
1657 | out: | |
cd649b8b | 1658 | return ret ? ret : count; |
c71a8961 | 1659 | } |
cd649b8b | 1660 | |
1d54ad6d LZ |
1661 | int blk_trace_init_sysfs(struct device *dev) |
1662 | { | |
1663 | return sysfs_create_group(&dev->kobj, &blk_trace_attr_group); | |
1664 | } | |
1665 | ||
55782138 LZ |
1666 | #endif /* CONFIG_BLK_DEV_IO_TRACE */ |
1667 | ||
1668 | #ifdef CONFIG_EVENT_TRACING | |
1669 | ||
1670 | void blk_dump_cmd(char *buf, struct request *rq) | |
1671 | { | |
1672 | int i, end; | |
1673 | int len = rq->cmd_len; | |
1674 | unsigned char *cmd = rq->cmd; | |
1675 | ||
1676 | if (!blk_pc_request(rq)) { | |
1677 | buf[0] = '\0'; | |
1678 | return; | |
1679 | } | |
1680 | ||
1681 | for (end = len - 1; end >= 0; end--) | |
1682 | if (cmd[end]) | |
1683 | break; | |
1684 | end++; | |
1685 | ||
1686 | for (i = 0; i < len; i++) { | |
1687 | buf += sprintf(buf, "%s%02x", i == 0 ? "" : " ", cmd[i]); | |
1688 | if (i == end && end != len - 1) { | |
1689 | sprintf(buf, " .."); | |
1690 | break; | |
1691 | } | |
1692 | } | |
1693 | } | |
1694 | ||
1695 | void blk_fill_rwbs(char *rwbs, u32 rw, int bytes) | |
1696 | { | |
1697 | int i = 0; | |
1698 | ||
1699 | if (rw & WRITE) | |
1700 | rwbs[i++] = 'W'; | |
1701 | else if (rw & 1 << BIO_RW_DISCARD) | |
1702 | rwbs[i++] = 'D'; | |
1703 | else if (bytes) | |
1704 | rwbs[i++] = 'R'; | |
1705 | else | |
1706 | rwbs[i++] = 'N'; | |
1707 | ||
1708 | if (rw & 1 << BIO_RW_AHEAD) | |
1709 | rwbs[i++] = 'A'; | |
1710 | if (rw & 1 << BIO_RW_BARRIER) | |
1711 | rwbs[i++] = 'B'; | |
1712 | if (rw & 1 << BIO_RW_SYNCIO) | |
1713 | rwbs[i++] = 'S'; | |
1714 | if (rw & 1 << BIO_RW_META) | |
1715 | rwbs[i++] = 'M'; | |
1716 | ||
1717 | rwbs[i] = '\0'; | |
1718 | } | |
1719 | ||
1720 | void blk_fill_rwbs_rq(char *rwbs, struct request *rq) | |
1721 | { | |
1722 | int rw = rq->cmd_flags & 0x03; | |
1723 | int bytes; | |
1724 | ||
1725 | if (blk_discard_rq(rq)) | |
1726 | rw |= (1 << BIO_RW_DISCARD); | |
1727 | ||
c9059598 | 1728 | bytes = blk_rq_bytes(rq); |
55782138 LZ |
1729 | |
1730 | blk_fill_rwbs(rwbs, rw, bytes); | |
1731 | } | |
1732 | ||
1733 | #endif /* CONFIG_EVENT_TRACING */ | |
1734 |