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Commit | Line | Data |
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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> | |
5a0e3ad6 | 24 | #include <linux/slab.h> |
2056a782 | 25 | #include <linux/debugfs.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 | 67 | struct ring_buffer_event *event = NULL; |
e77405ad | 68 | struct ring_buffer *buffer = NULL; |
18cea459 LZ |
69 | int pc = 0; |
70 | int cpu = smp_processor_id(); | |
71 | bool blk_tracer = blk_tracer_enabled; | |
72 | ||
73 | if (blk_tracer) { | |
e77405ad | 74 | buffer = blk_tr->buffer; |
18cea459 | 75 | pc = preempt_count(); |
e77405ad | 76 | event = trace_buffer_lock_reserve(buffer, TRACE_BLK, |
18cea459 LZ |
77 | sizeof(*t) + len, |
78 | 0, pc); | |
79 | if (!event) | |
80 | return; | |
81 | t = ring_buffer_event_data(event); | |
82 | goto record_it; | |
83 | } | |
be1c6341 | 84 | |
c71a8961 ACM |
85 | if (!bt->rchan) |
86 | return; | |
87 | ||
be1c6341 | 88 | t = relay_reserve(bt->rchan, sizeof(*t) + len); |
d3d9d2a5 | 89 | if (t) { |
d3d9d2a5 | 90 | t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; |
2997c8c4 | 91 | t->time = ktime_to_ns(ktime_get()); |
18cea459 | 92 | record_it: |
d3d9d2a5 JA |
93 | t->device = bt->dev; |
94 | t->action = action; | |
95 | t->pid = pid; | |
96 | t->cpu = cpu; | |
97 | t->pdu_len = len; | |
98 | memcpy((void *) t + sizeof(*t), data, len); | |
18cea459 LZ |
99 | |
100 | if (blk_tracer) | |
e77405ad | 101 | trace_buffer_unlock_commit(buffer, event, 0, pc); |
d3d9d2a5 | 102 | } |
be1c6341 OK |
103 | } |
104 | ||
2056a782 JA |
105 | /* |
106 | * Send out a notify for this process, if we haven't done so since a trace | |
107 | * started | |
108 | */ | |
109 | static void trace_note_tsk(struct blk_trace *bt, struct task_struct *tsk) | |
110 | { | |
a863055b JA |
111 | tsk->btrace_seq = blktrace_seq; |
112 | trace_note(bt, tsk->pid, BLK_TN_PROCESS, tsk->comm, sizeof(tsk->comm)); | |
be1c6341 | 113 | } |
2056a782 | 114 | |
be1c6341 OK |
115 | static void trace_note_time(struct blk_trace *bt) |
116 | { | |
117 | struct timespec now; | |
118 | unsigned long flags; | |
119 | u32 words[2]; | |
120 | ||
121 | getnstimeofday(&now); | |
122 | words[0] = now.tv_sec; | |
123 | words[1] = now.tv_nsec; | |
124 | ||
125 | local_irq_save(flags); | |
126 | trace_note(bt, 0, BLK_TN_TIMESTAMP, words, sizeof(words)); | |
127 | local_irq_restore(flags); | |
2056a782 JA |
128 | } |
129 | ||
9d5f09a4 AB |
130 | void __trace_note_message(struct blk_trace *bt, const char *fmt, ...) |
131 | { | |
132 | int n; | |
133 | va_list args; | |
14a73f54 | 134 | unsigned long flags; |
64565911 | 135 | char *buf; |
9d5f09a4 | 136 | |
18cea459 LZ |
137 | if (unlikely(bt->trace_state != Blktrace_running && |
138 | !blk_tracer_enabled)) | |
c71a8961 ACM |
139 | return; |
140 | ||
14a73f54 | 141 | local_irq_save(flags); |
64565911 | 142 | buf = per_cpu_ptr(bt->msg_data, smp_processor_id()); |
9d5f09a4 | 143 | va_start(args, fmt); |
64565911 | 144 | n = vscnprintf(buf, BLK_TN_MAX_MSG, fmt, args); |
9d5f09a4 AB |
145 | va_end(args); |
146 | ||
64565911 | 147 | trace_note(bt, 0, BLK_TN_MESSAGE, buf, n); |
14a73f54 | 148 | local_irq_restore(flags); |
9d5f09a4 AB |
149 | } |
150 | EXPORT_SYMBOL_GPL(__trace_note_message); | |
151 | ||
2056a782 JA |
152 | static int act_log_check(struct blk_trace *bt, u32 what, sector_t sector, |
153 | pid_t pid) | |
154 | { | |
155 | if (((bt->act_mask << BLK_TC_SHIFT) & what) == 0) | |
156 | return 1; | |
d0deef5b | 157 | if (sector && (sector < bt->start_lba || sector > bt->end_lba)) |
2056a782 JA |
158 | return 1; |
159 | if (bt->pid && pid != bt->pid) | |
160 | return 1; | |
161 | ||
162 | return 0; | |
163 | } | |
164 | ||
165 | /* | |
166 | * Data direction bit lookup | |
167 | */ | |
e4955c99 LZ |
168 | static const u32 ddir_act[2] = { BLK_TC_ACT(BLK_TC_READ), |
169 | BLK_TC_ACT(BLK_TC_WRITE) }; | |
2056a782 | 170 | |
7b6d91da CH |
171 | #define BLK_TC_HARDBARRIER BLK_TC_BARRIER |
172 | #define BLK_TC_RAHEAD BLK_TC_AHEAD | |
173 | ||
35ba8f70 | 174 | /* The ilog2() calls fall out because they're constant */ |
7b6d91da CH |
175 | #define MASK_TC_BIT(rw, __name) ((rw & REQ_ ## __name) << \ |
176 | (ilog2(BLK_TC_ ## __name) + BLK_TC_SHIFT - __REQ_ ## __name)) | |
2056a782 JA |
177 | |
178 | /* | |
179 | * The worker for the various blk_add_trace*() types. Fills out a | |
180 | * blk_io_trace structure and places it in a per-cpu subbuffer. | |
181 | */ | |
5f3ea37c | 182 | static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, |
2056a782 JA |
183 | int rw, u32 what, int error, int pdu_len, void *pdu_data) |
184 | { | |
185 | struct task_struct *tsk = current; | |
c71a8961 | 186 | struct ring_buffer_event *event = NULL; |
e77405ad | 187 | struct ring_buffer *buffer = NULL; |
2056a782 | 188 | struct blk_io_trace *t; |
0a987751 | 189 | unsigned long flags = 0; |
2056a782 JA |
190 | unsigned long *sequence; |
191 | pid_t pid; | |
c71a8961 | 192 | int cpu, pc = 0; |
18cea459 | 193 | bool blk_tracer = blk_tracer_enabled; |
2056a782 | 194 | |
18cea459 | 195 | if (unlikely(bt->trace_state != Blktrace_running && !blk_tracer)) |
2056a782 JA |
196 | return; |
197 | ||
198 | what |= ddir_act[rw & WRITE]; | |
7b6d91da CH |
199 | what |= MASK_TC_BIT(rw, HARDBARRIER); |
200 | what |= MASK_TC_BIT(rw, SYNC); | |
201 | what |= MASK_TC_BIT(rw, RAHEAD); | |
35ba8f70 DW |
202 | what |= MASK_TC_BIT(rw, META); |
203 | what |= MASK_TC_BIT(rw, DISCARD); | |
2056a782 JA |
204 | |
205 | pid = tsk->pid; | |
d0deef5b | 206 | if (act_log_check(bt, what, sector, pid)) |
2056a782 | 207 | return; |
c71a8961 ACM |
208 | cpu = raw_smp_processor_id(); |
209 | ||
18cea459 | 210 | if (blk_tracer) { |
c71a8961 ACM |
211 | tracing_record_cmdline(current); |
212 | ||
e77405ad | 213 | buffer = blk_tr->buffer; |
51a763dd | 214 | pc = preempt_count(); |
e77405ad | 215 | event = trace_buffer_lock_reserve(buffer, TRACE_BLK, |
51a763dd ACM |
216 | sizeof(*t) + pdu_len, |
217 | 0, pc); | |
c71a8961 ACM |
218 | if (!event) |
219 | return; | |
51a763dd | 220 | t = ring_buffer_event_data(event); |
c71a8961 ACM |
221 | goto record_it; |
222 | } | |
2056a782 JA |
223 | |
224 | /* | |
225 | * A word about the locking here - we disable interrupts to reserve | |
226 | * some space in the relay per-cpu buffer, to prevent an irq | |
14a73f54 | 227 | * from coming in and stepping on our toes. |
2056a782 JA |
228 | */ |
229 | local_irq_save(flags); | |
230 | ||
231 | if (unlikely(tsk->btrace_seq != blktrace_seq)) | |
232 | trace_note_tsk(bt, tsk); | |
233 | ||
234 | t = relay_reserve(bt->rchan, sizeof(*t) + pdu_len); | |
235 | if (t) { | |
2056a782 JA |
236 | sequence = per_cpu_ptr(bt->sequence, cpu); |
237 | ||
238 | t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; | |
239 | t->sequence = ++(*sequence); | |
2997c8c4 | 240 | t->time = ktime_to_ns(ktime_get()); |
c71a8961 | 241 | record_it: |
08a06b83 | 242 | /* |
939b3669 ACM |
243 | * These two are not needed in ftrace as they are in the |
244 | * generic trace_entry, filled by tracing_generic_entry_update, | |
245 | * but for the trace_event->bin() synthesizer benefit we do it | |
246 | * here too. | |
247 | */ | |
248 | t->cpu = cpu; | |
249 | t->pid = pid; | |
08a06b83 | 250 | |
2056a782 JA |
251 | t->sector = sector; |
252 | t->bytes = bytes; | |
253 | t->action = what; | |
2056a782 | 254 | t->device = bt->dev; |
2056a782 JA |
255 | t->error = error; |
256 | t->pdu_len = pdu_len; | |
257 | ||
258 | if (pdu_len) | |
259 | memcpy((void *) t + sizeof(*t), pdu_data, pdu_len); | |
c71a8961 | 260 | |
18cea459 | 261 | if (blk_tracer) { |
e77405ad | 262 | trace_buffer_unlock_commit(buffer, event, 0, pc); |
c71a8961 ACM |
263 | return; |
264 | } | |
2056a782 JA |
265 | } |
266 | ||
267 | local_irq_restore(flags); | |
268 | } | |
269 | ||
2056a782 | 270 | static struct dentry *blk_tree_root; |
11a57153 | 271 | static DEFINE_MUTEX(blk_tree_mutex); |
2056a782 | 272 | |
ad5dd549 | 273 | static void blk_trace_free(struct blk_trace *bt) |
2056a782 | 274 | { |
02c62304 | 275 | debugfs_remove(bt->msg_file); |
2056a782 | 276 | debugfs_remove(bt->dropped_file); |
f48fc4d3 | 277 | relay_close(bt->rchan); |
39cbb602 | 278 | debugfs_remove(bt->dir); |
2056a782 | 279 | free_percpu(bt->sequence); |
64565911 | 280 | free_percpu(bt->msg_data); |
2056a782 | 281 | kfree(bt); |
ad5dd549 LZ |
282 | } |
283 | ||
284 | static void blk_trace_cleanup(struct blk_trace *bt) | |
285 | { | |
286 | blk_trace_free(bt); | |
5f3ea37c ACM |
287 | if (atomic_dec_and_test(&blk_probes_ref)) |
288 | blk_unregister_tracepoints(); | |
2056a782 JA |
289 | } |
290 | ||
6da127ad | 291 | int blk_trace_remove(struct request_queue *q) |
2056a782 JA |
292 | { |
293 | struct blk_trace *bt; | |
294 | ||
295 | bt = xchg(&q->blk_trace, NULL); | |
296 | if (!bt) | |
297 | return -EINVAL; | |
298 | ||
55547204 | 299 | if (bt->trace_state != Blktrace_running) |
2056a782 JA |
300 | blk_trace_cleanup(bt); |
301 | ||
302 | return 0; | |
303 | } | |
6da127ad | 304 | EXPORT_SYMBOL_GPL(blk_trace_remove); |
2056a782 JA |
305 | |
306 | static int blk_dropped_open(struct inode *inode, struct file *filp) | |
307 | { | |
8e18e294 | 308 | filp->private_data = inode->i_private; |
2056a782 JA |
309 | |
310 | return 0; | |
311 | } | |
312 | ||
313 | static ssize_t blk_dropped_read(struct file *filp, char __user *buffer, | |
314 | size_t count, loff_t *ppos) | |
315 | { | |
316 | struct blk_trace *bt = filp->private_data; | |
317 | char buf[16]; | |
318 | ||
319 | snprintf(buf, sizeof(buf), "%u\n", atomic_read(&bt->dropped)); | |
320 | ||
321 | return simple_read_from_buffer(buffer, count, ppos, buf, strlen(buf)); | |
322 | } | |
323 | ||
2b8693c0 | 324 | static const struct file_operations blk_dropped_fops = { |
2056a782 JA |
325 | .owner = THIS_MODULE, |
326 | .open = blk_dropped_open, | |
327 | .read = blk_dropped_read, | |
6038f373 | 328 | .llseek = default_llseek, |
2056a782 JA |
329 | }; |
330 | ||
02c62304 AB |
331 | static int blk_msg_open(struct inode *inode, struct file *filp) |
332 | { | |
333 | filp->private_data = inode->i_private; | |
334 | ||
335 | return 0; | |
336 | } | |
337 | ||
338 | static ssize_t blk_msg_write(struct file *filp, const char __user *buffer, | |
339 | size_t count, loff_t *ppos) | |
340 | { | |
341 | char *msg; | |
342 | struct blk_trace *bt; | |
343 | ||
7635b03a | 344 | if (count >= BLK_TN_MAX_MSG) |
02c62304 AB |
345 | return -EINVAL; |
346 | ||
a4b3ada8 | 347 | msg = kmalloc(count + 1, GFP_KERNEL); |
02c62304 AB |
348 | if (msg == NULL) |
349 | return -ENOMEM; | |
350 | ||
351 | if (copy_from_user(msg, buffer, count)) { | |
352 | kfree(msg); | |
353 | return -EFAULT; | |
354 | } | |
355 | ||
a4b3ada8 | 356 | msg[count] = '\0'; |
02c62304 AB |
357 | bt = filp->private_data; |
358 | __trace_note_message(bt, "%s", msg); | |
359 | kfree(msg); | |
360 | ||
361 | return count; | |
362 | } | |
363 | ||
364 | static const struct file_operations blk_msg_fops = { | |
365 | .owner = THIS_MODULE, | |
366 | .open = blk_msg_open, | |
367 | .write = blk_msg_write, | |
6038f373 | 368 | .llseek = noop_llseek, |
02c62304 AB |
369 | }; |
370 | ||
2056a782 JA |
371 | /* |
372 | * Keep track of how many times we encountered a full subbuffer, to aid | |
373 | * the user space app in telling how many lost events there were. | |
374 | */ | |
375 | static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf, | |
376 | void *prev_subbuf, size_t prev_padding) | |
377 | { | |
378 | struct blk_trace *bt; | |
379 | ||
380 | if (!relay_buf_full(buf)) | |
381 | return 1; | |
382 | ||
383 | bt = buf->chan->private_data; | |
384 | atomic_inc(&bt->dropped); | |
385 | return 0; | |
386 | } | |
387 | ||
388 | static int blk_remove_buf_file_callback(struct dentry *dentry) | |
389 | { | |
390 | debugfs_remove(dentry); | |
f48fc4d3 | 391 | |
2056a782 JA |
392 | return 0; |
393 | } | |
394 | ||
395 | static struct dentry *blk_create_buf_file_callback(const char *filename, | |
396 | struct dentry *parent, | |
397 | int mode, | |
398 | struct rchan_buf *buf, | |
399 | int *is_global) | |
400 | { | |
401 | return debugfs_create_file(filename, mode, parent, buf, | |
402 | &relay_file_operations); | |
403 | } | |
404 | ||
405 | static struct rchan_callbacks blk_relay_callbacks = { | |
406 | .subbuf_start = blk_subbuf_start_callback, | |
407 | .create_buf_file = blk_create_buf_file_callback, | |
408 | .remove_buf_file = blk_remove_buf_file_callback, | |
409 | }; | |
410 | ||
9908c309 LZ |
411 | static void blk_trace_setup_lba(struct blk_trace *bt, |
412 | struct block_device *bdev) | |
413 | { | |
414 | struct hd_struct *part = NULL; | |
415 | ||
416 | if (bdev) | |
417 | part = bdev->bd_part; | |
418 | ||
419 | if (part) { | |
420 | bt->start_lba = part->start_sect; | |
421 | bt->end_lba = part->start_sect + part->nr_sects; | |
422 | } else { | |
423 | bt->start_lba = 0; | |
424 | bt->end_lba = -1ULL; | |
425 | } | |
426 | } | |
427 | ||
2056a782 JA |
428 | /* |
429 | * Setup everything required to start tracing | |
430 | */ | |
6da127ad | 431 | int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, |
d0deef5b SD |
432 | struct block_device *bdev, |
433 | struct blk_user_trace_setup *buts) | |
2056a782 | 434 | { |
2056a782 JA |
435 | struct blk_trace *old_bt, *bt = NULL; |
436 | struct dentry *dir = NULL; | |
2056a782 JA |
437 | int ret, i; |
438 | ||
171044d4 | 439 | if (!buts->buf_size || !buts->buf_nr) |
2056a782 JA |
440 | return -EINVAL; |
441 | ||
0497b345 JA |
442 | strncpy(buts->name, name, BLKTRACE_BDEV_SIZE); |
443 | buts->name[BLKTRACE_BDEV_SIZE - 1] = '\0'; | |
2056a782 JA |
444 | |
445 | /* | |
446 | * some device names have larger paths - convert the slashes | |
447 | * to underscores for this to work as expected | |
448 | */ | |
171044d4 AB |
449 | for (i = 0; i < strlen(buts->name); i++) |
450 | if (buts->name[i] == '/') | |
451 | buts->name[i] = '_'; | |
2056a782 | 452 | |
2056a782 JA |
453 | bt = kzalloc(sizeof(*bt), GFP_KERNEL); |
454 | if (!bt) | |
ad5dd549 | 455 | return -ENOMEM; |
2056a782 | 456 | |
ad5dd549 | 457 | ret = -ENOMEM; |
2056a782 JA |
458 | bt->sequence = alloc_percpu(unsigned long); |
459 | if (!bt->sequence) | |
460 | goto err; | |
461 | ||
313e458f | 462 | bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); |
64565911 JA |
463 | if (!bt->msg_data) |
464 | goto err; | |
465 | ||
2056a782 | 466 | ret = -ENOENT; |
f48fc4d3 | 467 | |
b5230b56 | 468 | mutex_lock(&blk_tree_mutex); |
f48fc4d3 JA |
469 | if (!blk_tree_root) { |
470 | blk_tree_root = debugfs_create_dir("block", NULL); | |
b5230b56 LZ |
471 | if (!blk_tree_root) { |
472 | mutex_unlock(&blk_tree_mutex); | |
1a17662e | 473 | goto err; |
b5230b56 | 474 | } |
f48fc4d3 | 475 | } |
b5230b56 | 476 | mutex_unlock(&blk_tree_mutex); |
f48fc4d3 JA |
477 | |
478 | dir = debugfs_create_dir(buts->name, blk_tree_root); | |
479 | ||
2056a782 JA |
480 | if (!dir) |
481 | goto err; | |
482 | ||
483 | bt->dir = dir; | |
6da127ad | 484 | bt->dev = dev; |
2056a782 JA |
485 | atomic_set(&bt->dropped, 0); |
486 | ||
487 | ret = -EIO; | |
939b3669 ACM |
488 | bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt, |
489 | &blk_dropped_fops); | |
2056a782 JA |
490 | if (!bt->dropped_file) |
491 | goto err; | |
492 | ||
02c62304 AB |
493 | bt->msg_file = debugfs_create_file("msg", 0222, dir, bt, &blk_msg_fops); |
494 | if (!bt->msg_file) | |
495 | goto err; | |
496 | ||
171044d4 AB |
497 | bt->rchan = relay_open("trace", dir, buts->buf_size, |
498 | buts->buf_nr, &blk_relay_callbacks, bt); | |
2056a782 JA |
499 | if (!bt->rchan) |
500 | goto err; | |
2056a782 | 501 | |
171044d4 | 502 | bt->act_mask = buts->act_mask; |
2056a782 JA |
503 | if (!bt->act_mask) |
504 | bt->act_mask = (u16) -1; | |
505 | ||
9908c309 | 506 | blk_trace_setup_lba(bt, bdev); |
2056a782 | 507 | |
d0deef5b SD |
508 | /* overwrite with user settings */ |
509 | if (buts->start_lba) | |
510 | bt->start_lba = buts->start_lba; | |
511 | if (buts->end_lba) | |
512 | bt->end_lba = buts->end_lba; | |
513 | ||
171044d4 | 514 | bt->pid = buts->pid; |
2056a782 JA |
515 | bt->trace_state = Blktrace_setup; |
516 | ||
517 | ret = -EBUSY; | |
518 | old_bt = xchg(&q->blk_trace, bt); | |
519 | if (old_bt) { | |
520 | (void) xchg(&q->blk_trace, old_bt); | |
521 | goto err; | |
522 | } | |
523 | ||
17ba97e3 | 524 | if (atomic_inc_return(&blk_probes_ref) == 1) |
cbe28296 LZ |
525 | blk_register_tracepoints(); |
526 | ||
2056a782 JA |
527 | return 0; |
528 | err: | |
ad5dd549 | 529 | blk_trace_free(bt); |
2056a782 JA |
530 | return ret; |
531 | } | |
171044d4 | 532 | |
6da127ad | 533 | int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, |
d0deef5b | 534 | struct block_device *bdev, |
6da127ad | 535 | char __user *arg) |
171044d4 AB |
536 | { |
537 | struct blk_user_trace_setup buts; | |
538 | int ret; | |
539 | ||
540 | ret = copy_from_user(&buts, arg, sizeof(buts)); | |
541 | if (ret) | |
542 | return -EFAULT; | |
543 | ||
d0deef5b | 544 | ret = do_blk_trace_setup(q, name, dev, bdev, &buts); |
171044d4 AB |
545 | if (ret) |
546 | return ret; | |
547 | ||
9a8c28c8 DM |
548 | if (copy_to_user(arg, &buts, sizeof(buts))) { |
549 | blk_trace_remove(q); | |
171044d4 | 550 | return -EFAULT; |
9a8c28c8 | 551 | } |
171044d4 AB |
552 | return 0; |
553 | } | |
6da127ad | 554 | EXPORT_SYMBOL_GPL(blk_trace_setup); |
2056a782 | 555 | |
62c2a7d9 AB |
556 | #if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64) |
557 | static int compat_blk_trace_setup(struct request_queue *q, char *name, | |
558 | dev_t dev, struct block_device *bdev, | |
559 | char __user *arg) | |
560 | { | |
561 | struct blk_user_trace_setup buts; | |
562 | struct compat_blk_user_trace_setup cbuts; | |
563 | int ret; | |
564 | ||
565 | if (copy_from_user(&cbuts, arg, sizeof(cbuts))) | |
566 | return -EFAULT; | |
567 | ||
568 | buts = (struct blk_user_trace_setup) { | |
569 | .act_mask = cbuts.act_mask, | |
570 | .buf_size = cbuts.buf_size, | |
571 | .buf_nr = cbuts.buf_nr, | |
572 | .start_lba = cbuts.start_lba, | |
573 | .end_lba = cbuts.end_lba, | |
574 | .pid = cbuts.pid, | |
575 | }; | |
576 | memcpy(&buts.name, &cbuts.name, 32); | |
577 | ||
578 | ret = do_blk_trace_setup(q, name, dev, bdev, &buts); | |
579 | if (ret) | |
580 | return ret; | |
581 | ||
582 | if (copy_to_user(arg, &buts.name, 32)) { | |
583 | blk_trace_remove(q); | |
584 | return -EFAULT; | |
585 | } | |
586 | ||
587 | return 0; | |
588 | } | |
589 | #endif | |
590 | ||
6da127ad | 591 | int blk_trace_startstop(struct request_queue *q, int start) |
2056a782 | 592 | { |
2056a782 | 593 | int ret; |
939b3669 | 594 | struct blk_trace *bt = q->blk_trace; |
2056a782 | 595 | |
939b3669 | 596 | if (bt == NULL) |
2056a782 JA |
597 | return -EINVAL; |
598 | ||
599 | /* | |
600 | * For starting a trace, we can transition from a setup or stopped | |
601 | * trace. For stopping a trace, the state must be running | |
602 | */ | |
603 | ret = -EINVAL; | |
604 | if (start) { | |
605 | if (bt->trace_state == Blktrace_setup || | |
606 | bt->trace_state == Blktrace_stopped) { | |
607 | blktrace_seq++; | |
608 | smp_mb(); | |
609 | bt->trace_state = Blktrace_running; | |
be1c6341 OK |
610 | |
611 | trace_note_time(bt); | |
2056a782 JA |
612 | ret = 0; |
613 | } | |
614 | } else { | |
615 | if (bt->trace_state == Blktrace_running) { | |
616 | bt->trace_state = Blktrace_stopped; | |
617 | relay_flush(bt->rchan); | |
618 | ret = 0; | |
619 | } | |
620 | } | |
621 | ||
622 | return ret; | |
623 | } | |
6da127ad | 624 | EXPORT_SYMBOL_GPL(blk_trace_startstop); |
2056a782 JA |
625 | |
626 | /** | |
627 | * blk_trace_ioctl: - handle the ioctls associated with tracing | |
628 | * @bdev: the block device | |
ef18012b | 629 | * @cmd: the ioctl cmd |
2056a782 JA |
630 | * @arg: the argument data, if any |
631 | * | |
632 | **/ | |
633 | int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) | |
634 | { | |
165125e1 | 635 | struct request_queue *q; |
2056a782 | 636 | int ret, start = 0; |
6da127ad | 637 | char b[BDEVNAME_SIZE]; |
2056a782 JA |
638 | |
639 | q = bdev_get_queue(bdev); | |
640 | if (!q) | |
641 | return -ENXIO; | |
642 | ||
643 | mutex_lock(&bdev->bd_mutex); | |
644 | ||
645 | switch (cmd) { | |
646 | case BLKTRACESETUP: | |
f36f21ec | 647 | bdevname(bdev, b); |
d0deef5b | 648 | ret = blk_trace_setup(q, b, bdev->bd_dev, bdev, arg); |
2056a782 | 649 | break; |
62c2a7d9 AB |
650 | #if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64) |
651 | case BLKTRACESETUP32: | |
652 | bdevname(bdev, b); | |
653 | ret = compat_blk_trace_setup(q, b, bdev->bd_dev, bdev, arg); | |
654 | break; | |
655 | #endif | |
2056a782 JA |
656 | case BLKTRACESTART: |
657 | start = 1; | |
658 | case BLKTRACESTOP: | |
659 | ret = blk_trace_startstop(q, start); | |
660 | break; | |
661 | case BLKTRACETEARDOWN: | |
662 | ret = blk_trace_remove(q); | |
663 | break; | |
664 | default: | |
665 | ret = -ENOTTY; | |
666 | break; | |
667 | } | |
668 | ||
669 | mutex_unlock(&bdev->bd_mutex); | |
670 | return ret; | |
671 | } | |
672 | ||
673 | /** | |
674 | * blk_trace_shutdown: - stop and cleanup trace structures | |
675 | * @q: the request queue associated with the device | |
676 | * | |
677 | **/ | |
165125e1 | 678 | void blk_trace_shutdown(struct request_queue *q) |
2056a782 | 679 | { |
6c5c9341 AD |
680 | if (q->blk_trace) { |
681 | blk_trace_startstop(q, 0); | |
682 | blk_trace_remove(q); | |
683 | } | |
2056a782 | 684 | } |
5f3ea37c ACM |
685 | |
686 | /* | |
687 | * blktrace probes | |
688 | */ | |
689 | ||
690 | /** | |
691 | * blk_add_trace_rq - Add a trace for a request oriented action | |
692 | * @q: queue the io is for | |
693 | * @rq: the source request | |
694 | * @what: the action | |
695 | * | |
696 | * Description: | |
697 | * Records an action against a request. Will log the bio offset + size. | |
698 | * | |
699 | **/ | |
700 | static void blk_add_trace_rq(struct request_queue *q, struct request *rq, | |
701 | u32 what) | |
702 | { | |
703 | struct blk_trace *bt = q->blk_trace; | |
704 | int rw = rq->cmd_flags & 0x03; | |
705 | ||
706 | if (likely(!bt)) | |
707 | return; | |
708 | ||
33659ebb | 709 | if (rq->cmd_flags & REQ_DISCARD) |
7b6d91da | 710 | rw |= REQ_DISCARD; |
5f3ea37c | 711 | |
8d57a98c AH |
712 | if (rq->cmd_flags & REQ_SECURE) |
713 | rw |= REQ_SECURE; | |
714 | ||
33659ebb | 715 | if (rq->cmd_type == REQ_TYPE_BLOCK_PC) { |
5f3ea37c | 716 | what |= BLK_TC_ACT(BLK_TC_PC); |
2e46e8b2 TH |
717 | __blk_add_trace(bt, 0, blk_rq_bytes(rq), rw, |
718 | what, rq->errors, rq->cmd_len, rq->cmd); | |
5f3ea37c ACM |
719 | } else { |
720 | what |= BLK_TC_ACT(BLK_TC_FS); | |
2e46e8b2 TH |
721 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), rw, |
722 | what, rq->errors, 0, NULL); | |
5f3ea37c ACM |
723 | } |
724 | } | |
725 | ||
38516ab5 SR |
726 | static void blk_add_trace_rq_abort(void *ignore, |
727 | struct request_queue *q, struct request *rq) | |
5f3ea37c ACM |
728 | { |
729 | blk_add_trace_rq(q, rq, BLK_TA_ABORT); | |
730 | } | |
731 | ||
38516ab5 SR |
732 | static void blk_add_trace_rq_insert(void *ignore, |
733 | struct request_queue *q, struct request *rq) | |
5f3ea37c ACM |
734 | { |
735 | blk_add_trace_rq(q, rq, BLK_TA_INSERT); | |
736 | } | |
737 | ||
38516ab5 SR |
738 | static void blk_add_trace_rq_issue(void *ignore, |
739 | struct request_queue *q, struct request *rq) | |
5f3ea37c ACM |
740 | { |
741 | blk_add_trace_rq(q, rq, BLK_TA_ISSUE); | |
742 | } | |
743 | ||
38516ab5 SR |
744 | static void blk_add_trace_rq_requeue(void *ignore, |
745 | struct request_queue *q, | |
939b3669 | 746 | struct request *rq) |
5f3ea37c ACM |
747 | { |
748 | blk_add_trace_rq(q, rq, BLK_TA_REQUEUE); | |
749 | } | |
750 | ||
38516ab5 SR |
751 | static void blk_add_trace_rq_complete(void *ignore, |
752 | struct request_queue *q, | |
939b3669 | 753 | struct request *rq) |
5f3ea37c ACM |
754 | { |
755 | blk_add_trace_rq(q, rq, BLK_TA_COMPLETE); | |
756 | } | |
757 | ||
758 | /** | |
759 | * blk_add_trace_bio - Add a trace for a bio oriented action | |
760 | * @q: queue the io is for | |
761 | * @bio: the source bio | |
762 | * @what: the action | |
763 | * | |
764 | * Description: | |
765 | * Records an action against a bio. Will log the bio offset + size. | |
766 | * | |
767 | **/ | |
768 | static void blk_add_trace_bio(struct request_queue *q, struct bio *bio, | |
769 | u32 what) | |
770 | { | |
771 | struct blk_trace *bt = q->blk_trace; | |
772 | ||
773 | if (likely(!bt)) | |
774 | return; | |
775 | ||
776 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, | |
777 | !bio_flagged(bio, BIO_UPTODATE), 0, NULL); | |
778 | } | |
779 | ||
38516ab5 SR |
780 | static void blk_add_trace_bio_bounce(void *ignore, |
781 | struct request_queue *q, struct bio *bio) | |
5f3ea37c ACM |
782 | { |
783 | blk_add_trace_bio(q, bio, BLK_TA_BOUNCE); | |
784 | } | |
785 | ||
38516ab5 SR |
786 | static void blk_add_trace_bio_complete(void *ignore, |
787 | struct request_queue *q, struct bio *bio) | |
5f3ea37c ACM |
788 | { |
789 | blk_add_trace_bio(q, bio, BLK_TA_COMPLETE); | |
790 | } | |
791 | ||
38516ab5 SR |
792 | static void blk_add_trace_bio_backmerge(void *ignore, |
793 | struct request_queue *q, | |
939b3669 | 794 | struct bio *bio) |
5f3ea37c ACM |
795 | { |
796 | blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE); | |
797 | } | |
798 | ||
38516ab5 SR |
799 | static void blk_add_trace_bio_frontmerge(void *ignore, |
800 | struct request_queue *q, | |
939b3669 | 801 | struct bio *bio) |
5f3ea37c ACM |
802 | { |
803 | blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE); | |
804 | } | |
805 | ||
38516ab5 SR |
806 | static void blk_add_trace_bio_queue(void *ignore, |
807 | struct request_queue *q, struct bio *bio) | |
5f3ea37c ACM |
808 | { |
809 | blk_add_trace_bio(q, bio, BLK_TA_QUEUE); | |
810 | } | |
811 | ||
38516ab5 SR |
812 | static void blk_add_trace_getrq(void *ignore, |
813 | struct request_queue *q, | |
939b3669 | 814 | struct bio *bio, int rw) |
5f3ea37c ACM |
815 | { |
816 | if (bio) | |
817 | blk_add_trace_bio(q, bio, BLK_TA_GETRQ); | |
818 | else { | |
819 | struct blk_trace *bt = q->blk_trace; | |
820 | ||
821 | if (bt) | |
822 | __blk_add_trace(bt, 0, 0, rw, BLK_TA_GETRQ, 0, 0, NULL); | |
823 | } | |
824 | } | |
825 | ||
826 | ||
38516ab5 SR |
827 | static void blk_add_trace_sleeprq(void *ignore, |
828 | struct request_queue *q, | |
939b3669 | 829 | struct bio *bio, int rw) |
5f3ea37c ACM |
830 | { |
831 | if (bio) | |
832 | blk_add_trace_bio(q, bio, BLK_TA_SLEEPRQ); | |
833 | else { | |
834 | struct blk_trace *bt = q->blk_trace; | |
835 | ||
836 | if (bt) | |
939b3669 ACM |
837 | __blk_add_trace(bt, 0, 0, rw, BLK_TA_SLEEPRQ, |
838 | 0, 0, NULL); | |
5f3ea37c ACM |
839 | } |
840 | } | |
841 | ||
38516ab5 | 842 | static void blk_add_trace_plug(void *ignore, struct request_queue *q) |
5f3ea37c ACM |
843 | { |
844 | struct blk_trace *bt = q->blk_trace; | |
845 | ||
846 | if (bt) | |
847 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_PLUG, 0, 0, NULL); | |
848 | } | |
849 | ||
38516ab5 | 850 | static void blk_add_trace_unplug_io(void *ignore, struct request_queue *q) |
5f3ea37c ACM |
851 | { |
852 | struct blk_trace *bt = q->blk_trace; | |
853 | ||
854 | if (bt) { | |
855 | unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; | |
856 | __be64 rpdu = cpu_to_be64(pdu); | |
857 | ||
858 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_IO, 0, | |
859 | sizeof(rpdu), &rpdu); | |
860 | } | |
861 | } | |
862 | ||
38516ab5 | 863 | static void blk_add_trace_unplug_timer(void *ignore, struct request_queue *q) |
5f3ea37c ACM |
864 | { |
865 | struct blk_trace *bt = q->blk_trace; | |
866 | ||
867 | if (bt) { | |
868 | unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; | |
869 | __be64 rpdu = cpu_to_be64(pdu); | |
870 | ||
871 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_TIMER, 0, | |
872 | sizeof(rpdu), &rpdu); | |
873 | } | |
874 | } | |
875 | ||
38516ab5 SR |
876 | static void blk_add_trace_split(void *ignore, |
877 | struct request_queue *q, struct bio *bio, | |
5f3ea37c ACM |
878 | unsigned int pdu) |
879 | { | |
880 | struct blk_trace *bt = q->blk_trace; | |
881 | ||
882 | if (bt) { | |
883 | __be64 rpdu = cpu_to_be64(pdu); | |
884 | ||
885 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, | |
886 | BLK_TA_SPLIT, !bio_flagged(bio, BIO_UPTODATE), | |
887 | sizeof(rpdu), &rpdu); | |
888 | } | |
889 | } | |
890 | ||
891 | /** | |
892 | * blk_add_trace_remap - Add a trace for a remap operation | |
546cf44a | 893 | * @ignore: trace callback data parameter (not used) |
5f3ea37c ACM |
894 | * @q: queue the io is for |
895 | * @bio: the source bio | |
896 | * @dev: target device | |
a42aaa3b | 897 | * @from: source sector |
5f3ea37c ACM |
898 | * |
899 | * Description: | |
900 | * Device mapper or raid target sometimes need to split a bio because | |
901 | * it spans a stripe (or similar). Add a trace for that action. | |
902 | * | |
903 | **/ | |
38516ab5 SR |
904 | static void blk_add_trace_remap(void *ignore, |
905 | struct request_queue *q, struct bio *bio, | |
906 | dev_t dev, sector_t from) | |
5f3ea37c ACM |
907 | { |
908 | struct blk_trace *bt = q->blk_trace; | |
909 | struct blk_io_trace_remap r; | |
910 | ||
911 | if (likely(!bt)) | |
912 | return; | |
913 | ||
a42aaa3b AB |
914 | r.device_from = cpu_to_be32(dev); |
915 | r.device_to = cpu_to_be32(bio->bi_bdev->bd_dev); | |
916 | r.sector_from = cpu_to_be64(from); | |
5f3ea37c | 917 | |
22a7c31a AB |
918 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, |
919 | BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), | |
920 | sizeof(r), &r); | |
5f3ea37c ACM |
921 | } |
922 | ||
b0da3f0d JN |
923 | /** |
924 | * blk_add_trace_rq_remap - Add a trace for a request-remap operation | |
546cf44a | 925 | * @ignore: trace callback data parameter (not used) |
b0da3f0d JN |
926 | * @q: queue the io is for |
927 | * @rq: the source request | |
928 | * @dev: target device | |
929 | * @from: source sector | |
930 | * | |
931 | * Description: | |
932 | * Device mapper remaps request to other devices. | |
933 | * Add a trace for that action. | |
934 | * | |
935 | **/ | |
38516ab5 SR |
936 | static void blk_add_trace_rq_remap(void *ignore, |
937 | struct request_queue *q, | |
b0da3f0d JN |
938 | struct request *rq, dev_t dev, |
939 | sector_t from) | |
940 | { | |
941 | struct blk_trace *bt = q->blk_trace; | |
942 | struct blk_io_trace_remap r; | |
943 | ||
944 | if (likely(!bt)) | |
945 | return; | |
946 | ||
947 | r.device_from = cpu_to_be32(dev); | |
948 | r.device_to = cpu_to_be32(disk_devt(rq->rq_disk)); | |
949 | r.sector_from = cpu_to_be64(from); | |
950 | ||
951 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), | |
952 | rq_data_dir(rq), BLK_TA_REMAP, !!rq->errors, | |
953 | sizeof(r), &r); | |
954 | } | |
955 | ||
5f3ea37c ACM |
956 | /** |
957 | * blk_add_driver_data - Add binary message with driver-specific data | |
958 | * @q: queue the io is for | |
959 | * @rq: io request | |
960 | * @data: driver-specific data | |
961 | * @len: length of driver-specific data | |
962 | * | |
963 | * Description: | |
964 | * Some drivers might want to write driver-specific data per request. | |
965 | * | |
966 | **/ | |
967 | void blk_add_driver_data(struct request_queue *q, | |
968 | struct request *rq, | |
969 | void *data, size_t len) | |
970 | { | |
971 | struct blk_trace *bt = q->blk_trace; | |
972 | ||
973 | if (likely(!bt)) | |
974 | return; | |
975 | ||
33659ebb | 976 | if (rq->cmd_type == REQ_TYPE_BLOCK_PC) |
2e46e8b2 TH |
977 | __blk_add_trace(bt, 0, blk_rq_bytes(rq), 0, |
978 | BLK_TA_DRV_DATA, rq->errors, len, data); | |
5f3ea37c | 979 | else |
2e46e8b2 TH |
980 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), 0, |
981 | BLK_TA_DRV_DATA, rq->errors, len, data); | |
5f3ea37c ACM |
982 | } |
983 | EXPORT_SYMBOL_GPL(blk_add_driver_data); | |
984 | ||
3c289ba7 | 985 | static void blk_register_tracepoints(void) |
5f3ea37c ACM |
986 | { |
987 | int ret; | |
988 | ||
38516ab5 | 989 | ret = register_trace_block_rq_abort(blk_add_trace_rq_abort, NULL); |
5f3ea37c | 990 | WARN_ON(ret); |
38516ab5 | 991 | ret = register_trace_block_rq_insert(blk_add_trace_rq_insert, NULL); |
5f3ea37c | 992 | WARN_ON(ret); |
38516ab5 | 993 | ret = register_trace_block_rq_issue(blk_add_trace_rq_issue, NULL); |
5f3ea37c | 994 | WARN_ON(ret); |
38516ab5 | 995 | ret = register_trace_block_rq_requeue(blk_add_trace_rq_requeue, NULL); |
5f3ea37c | 996 | WARN_ON(ret); |
38516ab5 | 997 | ret = register_trace_block_rq_complete(blk_add_trace_rq_complete, NULL); |
5f3ea37c | 998 | WARN_ON(ret); |
38516ab5 | 999 | ret = register_trace_block_bio_bounce(blk_add_trace_bio_bounce, NULL); |
5f3ea37c | 1000 | WARN_ON(ret); |
38516ab5 | 1001 | ret = register_trace_block_bio_complete(blk_add_trace_bio_complete, NULL); |
5f3ea37c | 1002 | WARN_ON(ret); |
38516ab5 | 1003 | ret = register_trace_block_bio_backmerge(blk_add_trace_bio_backmerge, NULL); |
5f3ea37c | 1004 | WARN_ON(ret); |
38516ab5 | 1005 | ret = register_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge, NULL); |
5f3ea37c | 1006 | WARN_ON(ret); |
38516ab5 | 1007 | ret = register_trace_block_bio_queue(blk_add_trace_bio_queue, NULL); |
5f3ea37c | 1008 | WARN_ON(ret); |
38516ab5 | 1009 | ret = register_trace_block_getrq(blk_add_trace_getrq, NULL); |
5f3ea37c | 1010 | WARN_ON(ret); |
38516ab5 | 1011 | ret = register_trace_block_sleeprq(blk_add_trace_sleeprq, NULL); |
5f3ea37c | 1012 | WARN_ON(ret); |
38516ab5 | 1013 | ret = register_trace_block_plug(blk_add_trace_plug, NULL); |
5f3ea37c | 1014 | WARN_ON(ret); |
38516ab5 | 1015 | ret = register_trace_block_unplug_timer(blk_add_trace_unplug_timer, NULL); |
5f3ea37c | 1016 | WARN_ON(ret); |
38516ab5 | 1017 | ret = register_trace_block_unplug_io(blk_add_trace_unplug_io, NULL); |
5f3ea37c | 1018 | WARN_ON(ret); |
38516ab5 | 1019 | ret = register_trace_block_split(blk_add_trace_split, NULL); |
5f3ea37c | 1020 | WARN_ON(ret); |
38516ab5 | 1021 | ret = register_trace_block_remap(blk_add_trace_remap, NULL); |
5f3ea37c | 1022 | WARN_ON(ret); |
38516ab5 | 1023 | ret = register_trace_block_rq_remap(blk_add_trace_rq_remap, NULL); |
b0da3f0d | 1024 | WARN_ON(ret); |
5f3ea37c ACM |
1025 | } |
1026 | ||
1027 | static void blk_unregister_tracepoints(void) | |
1028 | { | |
38516ab5 SR |
1029 | unregister_trace_block_rq_remap(blk_add_trace_rq_remap, NULL); |
1030 | unregister_trace_block_remap(blk_add_trace_remap, NULL); | |
1031 | unregister_trace_block_split(blk_add_trace_split, NULL); | |
1032 | unregister_trace_block_unplug_io(blk_add_trace_unplug_io, NULL); | |
1033 | unregister_trace_block_unplug_timer(blk_add_trace_unplug_timer, NULL); | |
1034 | unregister_trace_block_plug(blk_add_trace_plug, NULL); | |
1035 | unregister_trace_block_sleeprq(blk_add_trace_sleeprq, NULL); | |
1036 | unregister_trace_block_getrq(blk_add_trace_getrq, NULL); | |
1037 | unregister_trace_block_bio_queue(blk_add_trace_bio_queue, NULL); | |
1038 | unregister_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge, NULL); | |
1039 | unregister_trace_block_bio_backmerge(blk_add_trace_bio_backmerge, NULL); | |
1040 | unregister_trace_block_bio_complete(blk_add_trace_bio_complete, NULL); | |
1041 | unregister_trace_block_bio_bounce(blk_add_trace_bio_bounce, NULL); | |
1042 | unregister_trace_block_rq_complete(blk_add_trace_rq_complete, NULL); | |
1043 | unregister_trace_block_rq_requeue(blk_add_trace_rq_requeue, NULL); | |
1044 | unregister_trace_block_rq_issue(blk_add_trace_rq_issue, NULL); | |
1045 | unregister_trace_block_rq_insert(blk_add_trace_rq_insert, NULL); | |
1046 | unregister_trace_block_rq_abort(blk_add_trace_rq_abort, NULL); | |
5f3ea37c ACM |
1047 | |
1048 | tracepoint_synchronize_unregister(); | |
1049 | } | |
c71a8961 ACM |
1050 | |
1051 | /* | |
1052 | * struct blk_io_tracer formatting routines | |
1053 | */ | |
1054 | ||
1055 | static void fill_rwbs(char *rwbs, const struct blk_io_trace *t) | |
1056 | { | |
157f9c00 | 1057 | int i = 0; |
65796348 | 1058 | int tc = t->action >> BLK_TC_SHIFT; |
157f9c00 | 1059 | |
18cea459 LZ |
1060 | if (t->action == BLK_TN_MESSAGE) { |
1061 | rwbs[i++] = 'N'; | |
1062 | goto out; | |
1063 | } | |
1064 | ||
65796348 | 1065 | if (tc & BLK_TC_DISCARD) |
157f9c00 | 1066 | rwbs[i++] = 'D'; |
65796348 | 1067 | else if (tc & BLK_TC_WRITE) |
157f9c00 ACM |
1068 | rwbs[i++] = 'W'; |
1069 | else if (t->bytes) | |
1070 | rwbs[i++] = 'R'; | |
1071 | else | |
1072 | rwbs[i++] = 'N'; | |
1073 | ||
65796348 | 1074 | if (tc & BLK_TC_AHEAD) |
157f9c00 | 1075 | rwbs[i++] = 'A'; |
65796348 | 1076 | if (tc & BLK_TC_BARRIER) |
157f9c00 | 1077 | rwbs[i++] = 'B'; |
65796348 | 1078 | if (tc & BLK_TC_SYNC) |
157f9c00 | 1079 | rwbs[i++] = 'S'; |
65796348 | 1080 | if (tc & BLK_TC_META) |
157f9c00 | 1081 | rwbs[i++] = 'M'; |
18cea459 | 1082 | out: |
157f9c00 | 1083 | rwbs[i] = '\0'; |
c71a8961 ACM |
1084 | } |
1085 | ||
1086 | static inline | |
1087 | const struct blk_io_trace *te_blk_io_trace(const struct trace_entry *ent) | |
1088 | { | |
1089 | return (const struct blk_io_trace *)ent; | |
1090 | } | |
1091 | ||
1092 | static inline const void *pdu_start(const struct trace_entry *ent) | |
1093 | { | |
1094 | return te_blk_io_trace(ent) + 1; | |
1095 | } | |
1096 | ||
66de7792 LZ |
1097 | static inline u32 t_action(const struct trace_entry *ent) |
1098 | { | |
1099 | return te_blk_io_trace(ent)->action; | |
1100 | } | |
1101 | ||
1102 | static inline u32 t_bytes(const struct trace_entry *ent) | |
1103 | { | |
1104 | return te_blk_io_trace(ent)->bytes; | |
1105 | } | |
1106 | ||
c71a8961 ACM |
1107 | static inline u32 t_sec(const struct trace_entry *ent) |
1108 | { | |
1109 | return te_blk_io_trace(ent)->bytes >> 9; | |
1110 | } | |
1111 | ||
1112 | static inline unsigned long long t_sector(const struct trace_entry *ent) | |
1113 | { | |
1114 | return te_blk_io_trace(ent)->sector; | |
1115 | } | |
1116 | ||
1117 | static inline __u16 t_error(const struct trace_entry *ent) | |
1118 | { | |
e0dc81be | 1119 | return te_blk_io_trace(ent)->error; |
c71a8961 ACM |
1120 | } |
1121 | ||
1122 | static __u64 get_pdu_int(const struct trace_entry *ent) | |
1123 | { | |
1124 | const __u64 *val = pdu_start(ent); | |
1125 | return be64_to_cpu(*val); | |
1126 | } | |
1127 | ||
1128 | static void get_pdu_remap(const struct trace_entry *ent, | |
1129 | struct blk_io_trace_remap *r) | |
1130 | { | |
1131 | const struct blk_io_trace_remap *__r = pdu_start(ent); | |
a42aaa3b | 1132 | __u64 sector_from = __r->sector_from; |
c71a8961 | 1133 | |
c71a8961 | 1134 | r->device_from = be32_to_cpu(__r->device_from); |
a42aaa3b AB |
1135 | r->device_to = be32_to_cpu(__r->device_to); |
1136 | r->sector_from = be64_to_cpu(sector_from); | |
c71a8961 ACM |
1137 | } |
1138 | ||
b6a4b0c3 LZ |
1139 | typedef int (blk_log_action_t) (struct trace_iterator *iter, const char *act); |
1140 | ||
1141 | static int blk_log_action_classic(struct trace_iterator *iter, const char *act) | |
c71a8961 ACM |
1142 | { |
1143 | char rwbs[6]; | |
35ac51bf LZ |
1144 | unsigned long long ts = iter->ts; |
1145 | unsigned long nsec_rem = do_div(ts, NSEC_PER_SEC); | |
c71a8961 | 1146 | unsigned secs = (unsigned long)ts; |
b6a4b0c3 | 1147 | const struct blk_io_trace *t = te_blk_io_trace(iter->ent); |
c71a8961 ACM |
1148 | |
1149 | fill_rwbs(rwbs, t); | |
1150 | ||
1151 | return trace_seq_printf(&iter->seq, | |
35ac51bf | 1152 | "%3d,%-3d %2d %5d.%09lu %5u %2s %3s ", |
c71a8961 | 1153 | MAJOR(t->device), MINOR(t->device), iter->cpu, |
b6a4b0c3 | 1154 | secs, nsec_rem, iter->ent->pid, act, rwbs); |
c71a8961 ACM |
1155 | } |
1156 | ||
b6a4b0c3 | 1157 | static int blk_log_action(struct trace_iterator *iter, const char *act) |
c71a8961 ACM |
1158 | { |
1159 | char rwbs[6]; | |
b6a4b0c3 LZ |
1160 | const struct blk_io_trace *t = te_blk_io_trace(iter->ent); |
1161 | ||
c71a8961 | 1162 | fill_rwbs(rwbs, t); |
b6a4b0c3 | 1163 | return trace_seq_printf(&iter->seq, "%3d,%-3d %2s %3s ", |
c71a8961 ACM |
1164 | MAJOR(t->device), MINOR(t->device), act, rwbs); |
1165 | } | |
1166 | ||
66de7792 LZ |
1167 | static int blk_log_dump_pdu(struct trace_seq *s, const struct trace_entry *ent) |
1168 | { | |
04986257 | 1169 | const unsigned char *pdu_buf; |
66de7792 LZ |
1170 | int pdu_len; |
1171 | int i, end, ret; | |
1172 | ||
1173 | pdu_buf = pdu_start(ent); | |
1174 | pdu_len = te_blk_io_trace(ent)->pdu_len; | |
1175 | ||
1176 | if (!pdu_len) | |
1177 | return 1; | |
1178 | ||
1179 | /* find the last zero that needs to be printed */ | |
1180 | for (end = pdu_len - 1; end >= 0; end--) | |
1181 | if (pdu_buf[end]) | |
1182 | break; | |
1183 | end++; | |
1184 | ||
1185 | if (!trace_seq_putc(s, '(')) | |
1186 | return 0; | |
1187 | ||
1188 | for (i = 0; i < pdu_len; i++) { | |
1189 | ||
1190 | ret = trace_seq_printf(s, "%s%02x", | |
1191 | i == 0 ? "" : " ", pdu_buf[i]); | |
1192 | if (!ret) | |
1193 | return ret; | |
1194 | ||
1195 | /* | |
1196 | * stop when the rest is just zeroes and indicate so | |
1197 | * with a ".." appended | |
1198 | */ | |
1199 | if (i == end && end != pdu_len - 1) | |
1200 | return trace_seq_puts(s, " ..) "); | |
1201 | } | |
1202 | ||
1203 | return trace_seq_puts(s, ") "); | |
1204 | } | |
1205 | ||
c71a8961 ACM |
1206 | static int blk_log_generic(struct trace_seq *s, const struct trace_entry *ent) |
1207 | { | |
4ca53085 SR |
1208 | char cmd[TASK_COMM_LEN]; |
1209 | ||
1210 | trace_find_cmdline(ent->pid, cmd); | |
c71a8961 | 1211 | |
66de7792 LZ |
1212 | if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { |
1213 | int ret; | |
1214 | ||
1215 | ret = trace_seq_printf(s, "%u ", t_bytes(ent)); | |
1216 | if (!ret) | |
1217 | return 0; | |
1218 | ret = blk_log_dump_pdu(s, ent); | |
1219 | if (!ret) | |
1220 | return 0; | |
1221 | return trace_seq_printf(s, "[%s]\n", cmd); | |
1222 | } else { | |
1223 | if (t_sec(ent)) | |
1224 | return trace_seq_printf(s, "%llu + %u [%s]\n", | |
1225 | t_sector(ent), t_sec(ent), cmd); | |
1226 | return trace_seq_printf(s, "[%s]\n", cmd); | |
1227 | } | |
c71a8961 ACM |
1228 | } |
1229 | ||
157f9c00 ACM |
1230 | static int blk_log_with_error(struct trace_seq *s, |
1231 | const struct trace_entry *ent) | |
c71a8961 | 1232 | { |
66de7792 LZ |
1233 | if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { |
1234 | int ret; | |
1235 | ||
1236 | ret = blk_log_dump_pdu(s, ent); | |
1237 | if (ret) | |
1238 | return trace_seq_printf(s, "[%d]\n", t_error(ent)); | |
1239 | return 0; | |
1240 | } else { | |
1241 | if (t_sec(ent)) | |
1242 | return trace_seq_printf(s, "%llu + %u [%d]\n", | |
1243 | t_sector(ent), | |
1244 | t_sec(ent), t_error(ent)); | |
1245 | return trace_seq_printf(s, "%llu [%d]\n", | |
1246 | t_sector(ent), t_error(ent)); | |
1247 | } | |
c71a8961 ACM |
1248 | } |
1249 | ||
1250 | static int blk_log_remap(struct trace_seq *s, const struct trace_entry *ent) | |
1251 | { | |
a42aaa3b | 1252 | struct blk_io_trace_remap r = { .device_from = 0, }; |
c71a8961 ACM |
1253 | |
1254 | get_pdu_remap(ent, &r); | |
1255 | return trace_seq_printf(s, "%llu + %u <- (%d,%d) %llu\n", | |
a42aaa3b AB |
1256 | t_sector(ent), t_sec(ent), |
1257 | MAJOR(r.device_from), MINOR(r.device_from), | |
1258 | (unsigned long long)r.sector_from); | |
c71a8961 ACM |
1259 | } |
1260 | ||
1261 | static int blk_log_plug(struct trace_seq *s, const struct trace_entry *ent) | |
1262 | { | |
4ca53085 SR |
1263 | char cmd[TASK_COMM_LEN]; |
1264 | ||
1265 | trace_find_cmdline(ent->pid, cmd); | |
1266 | ||
1267 | return trace_seq_printf(s, "[%s]\n", cmd); | |
c71a8961 ACM |
1268 | } |
1269 | ||
1270 | static int blk_log_unplug(struct trace_seq *s, const struct trace_entry *ent) | |
1271 | { | |
4ca53085 SR |
1272 | char cmd[TASK_COMM_LEN]; |
1273 | ||
1274 | trace_find_cmdline(ent->pid, cmd); | |
1275 | ||
1276 | return trace_seq_printf(s, "[%s] %llu\n", cmd, get_pdu_int(ent)); | |
c71a8961 ACM |
1277 | } |
1278 | ||
1279 | static int blk_log_split(struct trace_seq *s, const struct trace_entry *ent) | |
1280 | { | |
4ca53085 SR |
1281 | char cmd[TASK_COMM_LEN]; |
1282 | ||
1283 | trace_find_cmdline(ent->pid, cmd); | |
1284 | ||
c71a8961 | 1285 | return trace_seq_printf(s, "%llu / %llu [%s]\n", t_sector(ent), |
4ca53085 | 1286 | get_pdu_int(ent), cmd); |
c71a8961 ACM |
1287 | } |
1288 | ||
18cea459 LZ |
1289 | static int blk_log_msg(struct trace_seq *s, const struct trace_entry *ent) |
1290 | { | |
1291 | int ret; | |
1292 | const struct blk_io_trace *t = te_blk_io_trace(ent); | |
1293 | ||
1294 | ret = trace_seq_putmem(s, t + 1, t->pdu_len); | |
1295 | if (ret) | |
1296 | return trace_seq_putc(s, '\n'); | |
1297 | return ret; | |
1298 | } | |
1299 | ||
c71a8961 ACM |
1300 | /* |
1301 | * struct tracer operations | |
1302 | */ | |
1303 | ||
1304 | static void blk_tracer_print_header(struct seq_file *m) | |
1305 | { | |
1306 | if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) | |
1307 | return; | |
1308 | seq_puts(m, "# DEV CPU TIMESTAMP PID ACT FLG\n" | |
1309 | "# | | | | | |\n"); | |
1310 | } | |
1311 | ||
1312 | static void blk_tracer_start(struct trace_array *tr) | |
1313 | { | |
ad5dd549 | 1314 | blk_tracer_enabled = true; |
c71a8961 ACM |
1315 | } |
1316 | ||
1317 | static int blk_tracer_init(struct trace_array *tr) | |
1318 | { | |
1319 | blk_tr = tr; | |
1320 | blk_tracer_start(tr); | |
c71a8961 ACM |
1321 | return 0; |
1322 | } | |
1323 | ||
1324 | static void blk_tracer_stop(struct trace_array *tr) | |
1325 | { | |
ad5dd549 | 1326 | blk_tracer_enabled = false; |
c71a8961 ACM |
1327 | } |
1328 | ||
1329 | static void blk_tracer_reset(struct trace_array *tr) | |
1330 | { | |
c71a8961 ACM |
1331 | blk_tracer_stop(tr); |
1332 | } | |
1333 | ||
e4955c99 | 1334 | static const struct { |
c71a8961 | 1335 | const char *act[2]; |
ef18012b | 1336 | int (*print)(struct trace_seq *s, const struct trace_entry *ent); |
e4955c99 | 1337 | } what2act[] = { |
ef18012b | 1338 | [__BLK_TA_QUEUE] = {{ "Q", "queue" }, blk_log_generic }, |
c71a8961 ACM |
1339 | [__BLK_TA_BACKMERGE] = {{ "M", "backmerge" }, blk_log_generic }, |
1340 | [__BLK_TA_FRONTMERGE] = {{ "F", "frontmerge" }, blk_log_generic }, | |
1341 | [__BLK_TA_GETRQ] = {{ "G", "getrq" }, blk_log_generic }, | |
1342 | [__BLK_TA_SLEEPRQ] = {{ "S", "sleeprq" }, blk_log_generic }, | |
1343 | [__BLK_TA_REQUEUE] = {{ "R", "requeue" }, blk_log_with_error }, | |
1344 | [__BLK_TA_ISSUE] = {{ "D", "issue" }, blk_log_generic }, | |
1345 | [__BLK_TA_COMPLETE] = {{ "C", "complete" }, blk_log_with_error }, | |
1346 | [__BLK_TA_PLUG] = {{ "P", "plug" }, blk_log_plug }, | |
1347 | [__BLK_TA_UNPLUG_IO] = {{ "U", "unplug_io" }, blk_log_unplug }, | |
1348 | [__BLK_TA_UNPLUG_TIMER] = {{ "UT", "unplug_timer" }, blk_log_unplug }, | |
1349 | [__BLK_TA_INSERT] = {{ "I", "insert" }, blk_log_generic }, | |
1350 | [__BLK_TA_SPLIT] = {{ "X", "split" }, blk_log_split }, | |
1351 | [__BLK_TA_BOUNCE] = {{ "B", "bounce" }, blk_log_generic }, | |
1352 | [__BLK_TA_REMAP] = {{ "A", "remap" }, blk_log_remap }, | |
1353 | }; | |
1354 | ||
b6a4b0c3 LZ |
1355 | static enum print_line_t print_one_line(struct trace_iterator *iter, |
1356 | bool classic) | |
c71a8961 | 1357 | { |
2c9b238e | 1358 | struct trace_seq *s = &iter->seq; |
b6a4b0c3 LZ |
1359 | const struct blk_io_trace *t; |
1360 | u16 what; | |
c71a8961 | 1361 | int ret; |
b6a4b0c3 LZ |
1362 | bool long_act; |
1363 | blk_log_action_t *log_action; | |
c71a8961 | 1364 | |
b6a4b0c3 LZ |
1365 | t = te_blk_io_trace(iter->ent); |
1366 | what = t->action & ((1 << BLK_TC_SHIFT) - 1); | |
1367 | long_act = !!(trace_flags & TRACE_ITER_VERBOSE); | |
1368 | log_action = classic ? &blk_log_action_classic : &blk_log_action; | |
08a06b83 | 1369 | |
18cea459 LZ |
1370 | if (t->action == BLK_TN_MESSAGE) { |
1371 | ret = log_action(iter, long_act ? "message" : "m"); | |
1372 | if (ret) | |
1373 | ret = blk_log_msg(s, iter->ent); | |
1374 | goto out; | |
1375 | } | |
1376 | ||
eb08f8eb | 1377 | if (unlikely(what == 0 || what >= ARRAY_SIZE(what2act))) |
b78825d6 | 1378 | ret = trace_seq_printf(s, "Unknown action %x\n", what); |
c71a8961 | 1379 | else { |
b6a4b0c3 | 1380 | ret = log_action(iter, what2act[what].act[long_act]); |
c71a8961 | 1381 | if (ret) |
2c9b238e | 1382 | ret = what2act[what].print(s, iter->ent); |
c71a8961 | 1383 | } |
18cea459 | 1384 | out: |
c71a8961 ACM |
1385 | return ret ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; |
1386 | } | |
1387 | ||
b6a4b0c3 | 1388 | static enum print_line_t blk_trace_event_print(struct trace_iterator *iter, |
a9a57763 | 1389 | int flags, struct trace_event *event) |
b6a4b0c3 | 1390 | { |
b6a4b0c3 LZ |
1391 | return print_one_line(iter, false); |
1392 | } | |
1393 | ||
08a06b83 ACM |
1394 | static int blk_trace_synthesize_old_trace(struct trace_iterator *iter) |
1395 | { | |
1396 | struct trace_seq *s = &iter->seq; | |
1397 | struct blk_io_trace *t = (struct blk_io_trace *)iter->ent; | |
1398 | const int offset = offsetof(struct blk_io_trace, sector); | |
1399 | struct blk_io_trace old = { | |
1400 | .magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION, | |
6c051ce0 | 1401 | .time = iter->ts, |
08a06b83 ACM |
1402 | }; |
1403 | ||
1404 | if (!trace_seq_putmem(s, &old, offset)) | |
1405 | return 0; | |
1406 | return trace_seq_putmem(s, &t->sector, | |
1407 | sizeof(old) - offset + t->pdu_len); | |
1408 | } | |
1409 | ||
ae7462b4 | 1410 | static enum print_line_t |
a9a57763 SR |
1411 | blk_trace_event_print_binary(struct trace_iterator *iter, int flags, |
1412 | struct trace_event *event) | |
08a06b83 ACM |
1413 | { |
1414 | return blk_trace_synthesize_old_trace(iter) ? | |
1415 | TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; | |
1416 | } | |
1417 | ||
c71a8961 ACM |
1418 | static enum print_line_t blk_tracer_print_line(struct trace_iterator *iter) |
1419 | { | |
c71a8961 ACM |
1420 | if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) |
1421 | return TRACE_TYPE_UNHANDLED; | |
1422 | ||
b6a4b0c3 | 1423 | return print_one_line(iter, true); |
c71a8961 ACM |
1424 | } |
1425 | ||
f3948f88 LZ |
1426 | static int blk_tracer_set_flag(u32 old_flags, u32 bit, int set) |
1427 | { | |
1428 | /* don't output context-info for blk_classic output */ | |
1429 | if (bit == TRACE_BLK_OPT_CLASSIC) { | |
1430 | if (set) | |
1431 | trace_flags &= ~TRACE_ITER_CONTEXT_INFO; | |
1432 | else | |
1433 | trace_flags |= TRACE_ITER_CONTEXT_INFO; | |
1434 | } | |
1435 | return 0; | |
1436 | } | |
1437 | ||
c71a8961 ACM |
1438 | static struct tracer blk_tracer __read_mostly = { |
1439 | .name = "blk", | |
1440 | .init = blk_tracer_init, | |
1441 | .reset = blk_tracer_reset, | |
1442 | .start = blk_tracer_start, | |
1443 | .stop = blk_tracer_stop, | |
1444 | .print_header = blk_tracer_print_header, | |
1445 | .print_line = blk_tracer_print_line, | |
1446 | .flags = &blk_tracer_flags, | |
f3948f88 | 1447 | .set_flag = blk_tracer_set_flag, |
c71a8961 ACM |
1448 | }; |
1449 | ||
a9a57763 | 1450 | static struct trace_event_functions trace_blk_event_funcs = { |
c71a8961 | 1451 | .trace = blk_trace_event_print, |
08a06b83 | 1452 | .binary = blk_trace_event_print_binary, |
c71a8961 ACM |
1453 | }; |
1454 | ||
a9a57763 SR |
1455 | static struct trace_event trace_blk_event = { |
1456 | .type = TRACE_BLK, | |
1457 | .funcs = &trace_blk_event_funcs, | |
1458 | }; | |
1459 | ||
c71a8961 ACM |
1460 | static int __init init_blk_tracer(void) |
1461 | { | |
1462 | if (!register_ftrace_event(&trace_blk_event)) { | |
1463 | pr_warning("Warning: could not register block events\n"); | |
1464 | return 1; | |
1465 | } | |
1466 | ||
1467 | if (register_tracer(&blk_tracer) != 0) { | |
1468 | pr_warning("Warning: could not register the block tracer\n"); | |
1469 | unregister_ftrace_event(&trace_blk_event); | |
1470 | return 1; | |
1471 | } | |
1472 | ||
1473 | return 0; | |
1474 | } | |
1475 | ||
1476 | device_initcall(init_blk_tracer); | |
1477 | ||
1478 | static int blk_trace_remove_queue(struct request_queue *q) | |
1479 | { | |
1480 | struct blk_trace *bt; | |
1481 | ||
1482 | bt = xchg(&q->blk_trace, NULL); | |
1483 | if (bt == NULL) | |
1484 | return -EINVAL; | |
1485 | ||
17ba97e3 LZ |
1486 | if (atomic_dec_and_test(&blk_probes_ref)) |
1487 | blk_unregister_tracepoints(); | |
1488 | ||
ad5dd549 | 1489 | blk_trace_free(bt); |
c71a8961 ACM |
1490 | return 0; |
1491 | } | |
1492 | ||
1493 | /* | |
1494 | * Setup everything required to start tracing | |
1495 | */ | |
9908c309 LZ |
1496 | static int blk_trace_setup_queue(struct request_queue *q, |
1497 | struct block_device *bdev) | |
c71a8961 ACM |
1498 | { |
1499 | struct blk_trace *old_bt, *bt = NULL; | |
18cea459 | 1500 | int ret = -ENOMEM; |
c71a8961 | 1501 | |
c71a8961 ACM |
1502 | bt = kzalloc(sizeof(*bt), GFP_KERNEL); |
1503 | if (!bt) | |
15152e44 | 1504 | return -ENOMEM; |
c71a8961 | 1505 | |
18cea459 LZ |
1506 | bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); |
1507 | if (!bt->msg_data) | |
1508 | goto free_bt; | |
1509 | ||
9908c309 | 1510 | bt->dev = bdev->bd_dev; |
c71a8961 | 1511 | bt->act_mask = (u16)-1; |
9908c309 LZ |
1512 | |
1513 | blk_trace_setup_lba(bt, bdev); | |
c71a8961 ACM |
1514 | |
1515 | old_bt = xchg(&q->blk_trace, bt); | |
1516 | if (old_bt != NULL) { | |
1517 | (void)xchg(&q->blk_trace, old_bt); | |
18cea459 LZ |
1518 | ret = -EBUSY; |
1519 | goto free_bt; | |
c71a8961 | 1520 | } |
15152e44 | 1521 | |
17ba97e3 LZ |
1522 | if (atomic_inc_return(&blk_probes_ref) == 1) |
1523 | blk_register_tracepoints(); | |
c71a8961 | 1524 | return 0; |
18cea459 LZ |
1525 | |
1526 | free_bt: | |
1527 | blk_trace_free(bt); | |
1528 | return ret; | |
c71a8961 ACM |
1529 | } |
1530 | ||
1531 | /* | |
1532 | * sysfs interface to enable and configure tracing | |
1533 | */ | |
1534 | ||
c71a8961 ACM |
1535 | static ssize_t sysfs_blk_trace_attr_show(struct device *dev, |
1536 | struct device_attribute *attr, | |
1537 | char *buf); | |
1538 | static ssize_t sysfs_blk_trace_attr_store(struct device *dev, | |
1539 | struct device_attribute *attr, | |
1540 | const char *buf, size_t count); | |
1541 | #define BLK_TRACE_DEVICE_ATTR(_name) \ | |
1542 | DEVICE_ATTR(_name, S_IRUGO | S_IWUSR, \ | |
1543 | sysfs_blk_trace_attr_show, \ | |
1544 | sysfs_blk_trace_attr_store) | |
1545 | ||
cd649b8b | 1546 | static BLK_TRACE_DEVICE_ATTR(enable); |
c71a8961 ACM |
1547 | static BLK_TRACE_DEVICE_ATTR(act_mask); |
1548 | static BLK_TRACE_DEVICE_ATTR(pid); | |
1549 | static BLK_TRACE_DEVICE_ATTR(start_lba); | |
1550 | static BLK_TRACE_DEVICE_ATTR(end_lba); | |
1551 | ||
1552 | static struct attribute *blk_trace_attrs[] = { | |
1553 | &dev_attr_enable.attr, | |
1554 | &dev_attr_act_mask.attr, | |
1555 | &dev_attr_pid.attr, | |
1556 | &dev_attr_start_lba.attr, | |
1557 | &dev_attr_end_lba.attr, | |
1558 | NULL | |
1559 | }; | |
1560 | ||
1561 | struct attribute_group blk_trace_attr_group = { | |
1562 | .name = "trace", | |
1563 | .attrs = blk_trace_attrs, | |
1564 | }; | |
1565 | ||
09341997 LZ |
1566 | static const struct { |
1567 | int mask; | |
1568 | const char *str; | |
1569 | } mask_maps[] = { | |
1570 | { BLK_TC_READ, "read" }, | |
1571 | { BLK_TC_WRITE, "write" }, | |
1572 | { BLK_TC_BARRIER, "barrier" }, | |
1573 | { BLK_TC_SYNC, "sync" }, | |
1574 | { BLK_TC_QUEUE, "queue" }, | |
1575 | { BLK_TC_REQUEUE, "requeue" }, | |
1576 | { BLK_TC_ISSUE, "issue" }, | |
1577 | { BLK_TC_COMPLETE, "complete" }, | |
1578 | { BLK_TC_FS, "fs" }, | |
1579 | { BLK_TC_PC, "pc" }, | |
1580 | { BLK_TC_AHEAD, "ahead" }, | |
1581 | { BLK_TC_META, "meta" }, | |
1582 | { BLK_TC_DISCARD, "discard" }, | |
1583 | { BLK_TC_DRV_DATA, "drv_data" }, | |
1584 | }; | |
1585 | ||
1586 | static int blk_trace_str2mask(const char *str) | |
c71a8961 | 1587 | { |
09341997 | 1588 | int i; |
c71a8961 | 1589 | int mask = 0; |
9eb85125 | 1590 | char *buf, *s, *token; |
c71a8961 | 1591 | |
9eb85125 LZ |
1592 | buf = kstrdup(str, GFP_KERNEL); |
1593 | if (buf == NULL) | |
c71a8961 | 1594 | return -ENOMEM; |
9eb85125 | 1595 | s = strstrip(buf); |
c71a8961 ACM |
1596 | |
1597 | while (1) { | |
09341997 LZ |
1598 | token = strsep(&s, ","); |
1599 | if (token == NULL) | |
c71a8961 ACM |
1600 | break; |
1601 | ||
09341997 LZ |
1602 | if (*token == '\0') |
1603 | continue; | |
1604 | ||
1605 | for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { | |
1606 | if (strcasecmp(token, mask_maps[i].str) == 0) { | |
1607 | mask |= mask_maps[i].mask; | |
1608 | break; | |
1609 | } | |
1610 | } | |
1611 | if (i == ARRAY_SIZE(mask_maps)) { | |
1612 | mask = -EINVAL; | |
1613 | break; | |
1614 | } | |
c71a8961 | 1615 | } |
9eb85125 | 1616 | kfree(buf); |
c71a8961 ACM |
1617 | |
1618 | return mask; | |
1619 | } | |
1620 | ||
09341997 LZ |
1621 | static ssize_t blk_trace_mask2str(char *buf, int mask) |
1622 | { | |
1623 | int i; | |
1624 | char *p = buf; | |
1625 | ||
1626 | for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { | |
1627 | if (mask & mask_maps[i].mask) { | |
1628 | p += sprintf(p, "%s%s", | |
1629 | (p == buf) ? "" : ",", mask_maps[i].str); | |
1630 | } | |
1631 | } | |
1632 | *p++ = '\n'; | |
1633 | ||
1634 | return p - buf; | |
1635 | } | |
1636 | ||
b125130b LZ |
1637 | static struct request_queue *blk_trace_get_queue(struct block_device *bdev) |
1638 | { | |
1639 | if (bdev->bd_disk == NULL) | |
1640 | return NULL; | |
1641 | ||
1642 | return bdev_get_queue(bdev); | |
1643 | } | |
1644 | ||
c71a8961 ACM |
1645 | static ssize_t sysfs_blk_trace_attr_show(struct device *dev, |
1646 | struct device_attribute *attr, | |
1647 | char *buf) | |
1648 | { | |
1649 | struct hd_struct *p = dev_to_part(dev); | |
1650 | struct request_queue *q; | |
1651 | struct block_device *bdev; | |
1652 | ssize_t ret = -ENXIO; | |
1653 | ||
c71a8961 ACM |
1654 | bdev = bdget(part_devt(p)); |
1655 | if (bdev == NULL) | |
01b284f9 | 1656 | goto out; |
c71a8961 | 1657 | |
b125130b | 1658 | q = blk_trace_get_queue(bdev); |
c71a8961 ACM |
1659 | if (q == NULL) |
1660 | goto out_bdput; | |
b125130b | 1661 | |
c71a8961 | 1662 | mutex_lock(&bdev->bd_mutex); |
cd649b8b LZ |
1663 | |
1664 | if (attr == &dev_attr_enable) { | |
1665 | ret = sprintf(buf, "%u\n", !!q->blk_trace); | |
1666 | goto out_unlock_bdev; | |
1667 | } | |
1668 | ||
c71a8961 ACM |
1669 | if (q->blk_trace == NULL) |
1670 | ret = sprintf(buf, "disabled\n"); | |
1671 | else if (attr == &dev_attr_act_mask) | |
09341997 | 1672 | ret = blk_trace_mask2str(buf, q->blk_trace->act_mask); |
c71a8961 ACM |
1673 | else if (attr == &dev_attr_pid) |
1674 | ret = sprintf(buf, "%u\n", q->blk_trace->pid); | |
1675 | else if (attr == &dev_attr_start_lba) | |
1676 | ret = sprintf(buf, "%llu\n", q->blk_trace->start_lba); | |
1677 | else if (attr == &dev_attr_end_lba) | |
1678 | ret = sprintf(buf, "%llu\n", q->blk_trace->end_lba); | |
cd649b8b LZ |
1679 | |
1680 | out_unlock_bdev: | |
c71a8961 ACM |
1681 | mutex_unlock(&bdev->bd_mutex); |
1682 | out_bdput: | |
1683 | bdput(bdev); | |
01b284f9 | 1684 | out: |
c71a8961 ACM |
1685 | return ret; |
1686 | } | |
1687 | ||
1688 | static ssize_t sysfs_blk_trace_attr_store(struct device *dev, | |
1689 | struct device_attribute *attr, | |
1690 | const char *buf, size_t count) | |
1691 | { | |
1692 | struct block_device *bdev; | |
1693 | struct request_queue *q; | |
1694 | struct hd_struct *p; | |
1695 | u64 value; | |
09341997 | 1696 | ssize_t ret = -EINVAL; |
c71a8961 ACM |
1697 | |
1698 | if (count == 0) | |
1699 | goto out; | |
1700 | ||
1701 | if (attr == &dev_attr_act_mask) { | |
1702 | if (sscanf(buf, "%llx", &value) != 1) { | |
1703 | /* Assume it is a list of trace category names */ | |
09341997 LZ |
1704 | ret = blk_trace_str2mask(buf); |
1705 | if (ret < 0) | |
c71a8961 | 1706 | goto out; |
09341997 | 1707 | value = ret; |
c71a8961 ACM |
1708 | } |
1709 | } else if (sscanf(buf, "%llu", &value) != 1) | |
1710 | goto out; | |
1711 | ||
09341997 LZ |
1712 | ret = -ENXIO; |
1713 | ||
c71a8961 ACM |
1714 | p = dev_to_part(dev); |
1715 | bdev = bdget(part_devt(p)); | |
1716 | if (bdev == NULL) | |
01b284f9 | 1717 | goto out; |
c71a8961 | 1718 | |
b125130b | 1719 | q = blk_trace_get_queue(bdev); |
c71a8961 ACM |
1720 | if (q == NULL) |
1721 | goto out_bdput; | |
1722 | ||
1723 | mutex_lock(&bdev->bd_mutex); | |
cd649b8b LZ |
1724 | |
1725 | if (attr == &dev_attr_enable) { | |
1726 | if (value) | |
9908c309 | 1727 | ret = blk_trace_setup_queue(q, bdev); |
cd649b8b LZ |
1728 | else |
1729 | ret = blk_trace_remove_queue(q); | |
1730 | goto out_unlock_bdev; | |
1731 | } | |
1732 | ||
c71a8961 ACM |
1733 | ret = 0; |
1734 | if (q->blk_trace == NULL) | |
9908c309 | 1735 | ret = blk_trace_setup_queue(q, bdev); |
c71a8961 ACM |
1736 | |
1737 | if (ret == 0) { | |
1738 | if (attr == &dev_attr_act_mask) | |
1739 | q->blk_trace->act_mask = value; | |
1740 | else if (attr == &dev_attr_pid) | |
1741 | q->blk_trace->pid = value; | |
1742 | else if (attr == &dev_attr_start_lba) | |
1743 | q->blk_trace->start_lba = value; | |
1744 | else if (attr == &dev_attr_end_lba) | |
1745 | q->blk_trace->end_lba = value; | |
c71a8961 | 1746 | } |
cd649b8b LZ |
1747 | |
1748 | out_unlock_bdev: | |
c71a8961 ACM |
1749 | mutex_unlock(&bdev->bd_mutex); |
1750 | out_bdput: | |
1751 | bdput(bdev); | |
c71a8961 | 1752 | out: |
cd649b8b | 1753 | return ret ? ret : count; |
c71a8961 | 1754 | } |
cd649b8b | 1755 | |
1d54ad6d LZ |
1756 | int blk_trace_init_sysfs(struct device *dev) |
1757 | { | |
1758 | return sysfs_create_group(&dev->kobj, &blk_trace_attr_group); | |
1759 | } | |
1760 | ||
48c0d4d4 ZK |
1761 | void blk_trace_remove_sysfs(struct device *dev) |
1762 | { | |
1763 | sysfs_remove_group(&dev->kobj, &blk_trace_attr_group); | |
1764 | } | |
1765 | ||
55782138 LZ |
1766 | #endif /* CONFIG_BLK_DEV_IO_TRACE */ |
1767 | ||
1768 | #ifdef CONFIG_EVENT_TRACING | |
1769 | ||
1770 | void blk_dump_cmd(char *buf, struct request *rq) | |
1771 | { | |
1772 | int i, end; | |
1773 | int len = rq->cmd_len; | |
1774 | unsigned char *cmd = rq->cmd; | |
1775 | ||
33659ebb | 1776 | if (rq->cmd_type != REQ_TYPE_BLOCK_PC) { |
55782138 LZ |
1777 | buf[0] = '\0'; |
1778 | return; | |
1779 | } | |
1780 | ||
1781 | for (end = len - 1; end >= 0; end--) | |
1782 | if (cmd[end]) | |
1783 | break; | |
1784 | end++; | |
1785 | ||
1786 | for (i = 0; i < len; i++) { | |
1787 | buf += sprintf(buf, "%s%02x", i == 0 ? "" : " ", cmd[i]); | |
1788 | if (i == end && end != len - 1) { | |
1789 | sprintf(buf, " .."); | |
1790 | break; | |
1791 | } | |
1792 | } | |
1793 | } | |
1794 | ||
1795 | void blk_fill_rwbs(char *rwbs, u32 rw, int bytes) | |
1796 | { | |
1797 | int i = 0; | |
1798 | ||
1799 | if (rw & WRITE) | |
1800 | rwbs[i++] = 'W'; | |
7b6d91da | 1801 | else if (rw & REQ_DISCARD) |
55782138 LZ |
1802 | rwbs[i++] = 'D'; |
1803 | else if (bytes) | |
1804 | rwbs[i++] = 'R'; | |
1805 | else | |
1806 | rwbs[i++] = 'N'; | |
1807 | ||
7b6d91da | 1808 | if (rw & REQ_RAHEAD) |
55782138 | 1809 | rwbs[i++] = 'A'; |
7b6d91da | 1810 | if (rw & REQ_HARDBARRIER) |
55782138 | 1811 | rwbs[i++] = 'B'; |
7b6d91da | 1812 | if (rw & REQ_SYNC) |
55782138 | 1813 | rwbs[i++] = 'S'; |
7b6d91da | 1814 | if (rw & REQ_META) |
55782138 | 1815 | rwbs[i++] = 'M'; |
8d57a98c AH |
1816 | if (rw & REQ_SECURE) |
1817 | rwbs[i++] = 'E'; | |
55782138 LZ |
1818 | |
1819 | rwbs[i] = '\0'; | |
1820 | } | |
1821 | ||
1822 | void blk_fill_rwbs_rq(char *rwbs, struct request *rq) | |
1823 | { | |
1824 | int rw = rq->cmd_flags & 0x03; | |
1825 | int bytes; | |
1826 | ||
33659ebb | 1827 | if (rq->cmd_flags & REQ_DISCARD) |
7b6d91da | 1828 | rw |= REQ_DISCARD; |
55782138 | 1829 | |
8d57a98c AH |
1830 | if (rq->cmd_flags & REQ_SECURE) |
1831 | rw |= REQ_SECURE; | |
1832 | ||
c9059598 | 1833 | bytes = blk_rq_bytes(rq); |
55782138 LZ |
1834 | |
1835 | blk_fill_rwbs(rwbs, rw, bytes); | |
1836 | } | |
1837 | ||
1838 | #endif /* CONFIG_EVENT_TRACING */ | |
1839 |