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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> |
6e5fdeed | 26 | #include <linux/export.h> |
be1c6341 | 27 | #include <linux/time.h> |
939b3669 | 28 | #include <linux/uaccess.h> |
55782138 LZ |
29 | |
30 | #include <trace/events/block.h> | |
31 | ||
2db270a8 | 32 | #include "trace_output.h" |
2056a782 | 33 | |
55782138 LZ |
34 | #ifdef CONFIG_BLK_DEV_IO_TRACE |
35 | ||
2056a782 JA |
36 | static unsigned int blktrace_seq __read_mostly = 1; |
37 | ||
c71a8961 | 38 | static struct trace_array *blk_tr; |
5006ea73 | 39 | static bool blk_tracer_enabled __read_mostly; |
c71a8961 ACM |
40 | |
41 | /* Select an alternative, minimalistic output than the original one */ | |
ef18012b | 42 | #define TRACE_BLK_OPT_CLASSIC 0x1 |
c71a8961 ACM |
43 | |
44 | static struct tracer_opt blk_tracer_opts[] = { | |
45 | /* Default disable the minimalistic output */ | |
157f9c00 | 46 | { TRACER_OPT(blk_classic, TRACE_BLK_OPT_CLASSIC) }, |
c71a8961 ACM |
47 | { } |
48 | }; | |
49 | ||
50 | static struct tracer_flags blk_tracer_flags = { | |
51 | .val = 0, | |
52 | .opts = blk_tracer_opts, | |
53 | }; | |
54 | ||
5f3ea37c | 55 | /* Global reference count of probes */ |
5f3ea37c ACM |
56 | static atomic_t blk_probes_ref = ATOMIC_INIT(0); |
57 | ||
3c289ba7 | 58 | static void blk_register_tracepoints(void); |
5f3ea37c ACM |
59 | static void blk_unregister_tracepoints(void); |
60 | ||
be1c6341 OK |
61 | /* |
62 | * Send out a notify message. | |
63 | */ | |
a863055b JA |
64 | static void trace_note(struct blk_trace *bt, pid_t pid, int action, |
65 | const void *data, size_t len) | |
be1c6341 OK |
66 | { |
67 | struct blk_io_trace *t; | |
18cea459 | 68 | struct ring_buffer_event *event = NULL; |
e77405ad | 69 | struct ring_buffer *buffer = NULL; |
18cea459 LZ |
70 | int pc = 0; |
71 | int cpu = smp_processor_id(); | |
72 | bool blk_tracer = blk_tracer_enabled; | |
73 | ||
74 | if (blk_tracer) { | |
e77405ad | 75 | buffer = blk_tr->buffer; |
18cea459 | 76 | pc = preempt_count(); |
e77405ad | 77 | event = trace_buffer_lock_reserve(buffer, TRACE_BLK, |
18cea459 LZ |
78 | sizeof(*t) + len, |
79 | 0, pc); | |
80 | if (!event) | |
81 | return; | |
82 | t = ring_buffer_event_data(event); | |
83 | goto record_it; | |
84 | } | |
be1c6341 | 85 | |
c71a8961 ACM |
86 | if (!bt->rchan) |
87 | return; | |
88 | ||
be1c6341 | 89 | t = relay_reserve(bt->rchan, sizeof(*t) + len); |
d3d9d2a5 | 90 | if (t) { |
d3d9d2a5 | 91 | t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; |
2997c8c4 | 92 | t->time = ktime_to_ns(ktime_get()); |
18cea459 | 93 | record_it: |
d3d9d2a5 JA |
94 | t->device = bt->dev; |
95 | t->action = action; | |
96 | t->pid = pid; | |
97 | t->cpu = cpu; | |
98 | t->pdu_len = len; | |
99 | memcpy((void *) t + sizeof(*t), data, len); | |
18cea459 LZ |
100 | |
101 | if (blk_tracer) | |
e77405ad | 102 | trace_buffer_unlock_commit(buffer, event, 0, pc); |
d3d9d2a5 | 103 | } |
be1c6341 OK |
104 | } |
105 | ||
2056a782 JA |
106 | /* |
107 | * Send out a notify for this process, if we haven't done so since a trace | |
108 | * started | |
109 | */ | |
110 | static void trace_note_tsk(struct blk_trace *bt, struct task_struct *tsk) | |
111 | { | |
a863055b JA |
112 | tsk->btrace_seq = blktrace_seq; |
113 | trace_note(bt, tsk->pid, BLK_TN_PROCESS, tsk->comm, sizeof(tsk->comm)); | |
be1c6341 | 114 | } |
2056a782 | 115 | |
be1c6341 OK |
116 | static void trace_note_time(struct blk_trace *bt) |
117 | { | |
118 | struct timespec now; | |
119 | unsigned long flags; | |
120 | u32 words[2]; | |
121 | ||
122 | getnstimeofday(&now); | |
123 | words[0] = now.tv_sec; | |
124 | words[1] = now.tv_nsec; | |
125 | ||
126 | local_irq_save(flags); | |
127 | trace_note(bt, 0, BLK_TN_TIMESTAMP, words, sizeof(words)); | |
128 | local_irq_restore(flags); | |
2056a782 JA |
129 | } |
130 | ||
9d5f09a4 AB |
131 | void __trace_note_message(struct blk_trace *bt, const char *fmt, ...) |
132 | { | |
133 | int n; | |
134 | va_list args; | |
14a73f54 | 135 | unsigned long flags; |
64565911 | 136 | char *buf; |
9d5f09a4 | 137 | |
18cea459 LZ |
138 | if (unlikely(bt->trace_state != Blktrace_running && |
139 | !blk_tracer_enabled)) | |
c71a8961 ACM |
140 | return; |
141 | ||
490da40d TM |
142 | /* |
143 | * If the BLK_TC_NOTIFY action mask isn't set, don't send any note | |
144 | * message to the trace. | |
145 | */ | |
146 | if (!(bt->act_mask & BLK_TC_NOTIFY)) | |
147 | return; | |
148 | ||
14a73f54 | 149 | local_irq_save(flags); |
64565911 | 150 | buf = per_cpu_ptr(bt->msg_data, smp_processor_id()); |
9d5f09a4 | 151 | va_start(args, fmt); |
64565911 | 152 | n = vscnprintf(buf, BLK_TN_MAX_MSG, fmt, args); |
9d5f09a4 AB |
153 | va_end(args); |
154 | ||
64565911 | 155 | trace_note(bt, 0, BLK_TN_MESSAGE, buf, n); |
14a73f54 | 156 | local_irq_restore(flags); |
9d5f09a4 AB |
157 | } |
158 | EXPORT_SYMBOL_GPL(__trace_note_message); | |
159 | ||
2056a782 JA |
160 | static int act_log_check(struct blk_trace *bt, u32 what, sector_t sector, |
161 | pid_t pid) | |
162 | { | |
163 | if (((bt->act_mask << BLK_TC_SHIFT) & what) == 0) | |
164 | return 1; | |
d0deef5b | 165 | if (sector && (sector < bt->start_lba || sector > bt->end_lba)) |
2056a782 JA |
166 | return 1; |
167 | if (bt->pid && pid != bt->pid) | |
168 | return 1; | |
169 | ||
170 | return 0; | |
171 | } | |
172 | ||
173 | /* | |
174 | * Data direction bit lookup | |
175 | */ | |
e4955c99 LZ |
176 | static const u32 ddir_act[2] = { BLK_TC_ACT(BLK_TC_READ), |
177 | BLK_TC_ACT(BLK_TC_WRITE) }; | |
2056a782 | 178 | |
7b6d91da CH |
179 | #define BLK_TC_RAHEAD BLK_TC_AHEAD |
180 | ||
35ba8f70 | 181 | /* The ilog2() calls fall out because they're constant */ |
7b6d91da CH |
182 | #define MASK_TC_BIT(rw, __name) ((rw & REQ_ ## __name) << \ |
183 | (ilog2(BLK_TC_ ## __name) + BLK_TC_SHIFT - __REQ_ ## __name)) | |
2056a782 JA |
184 | |
185 | /* | |
186 | * The worker for the various blk_add_trace*() types. Fills out a | |
187 | * blk_io_trace structure and places it in a per-cpu subbuffer. | |
188 | */ | |
5f3ea37c | 189 | static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, |
2056a782 JA |
190 | int rw, u32 what, int error, int pdu_len, void *pdu_data) |
191 | { | |
192 | struct task_struct *tsk = current; | |
c71a8961 | 193 | struct ring_buffer_event *event = NULL; |
e77405ad | 194 | struct ring_buffer *buffer = NULL; |
2056a782 | 195 | struct blk_io_trace *t; |
0a987751 | 196 | unsigned long flags = 0; |
2056a782 JA |
197 | unsigned long *sequence; |
198 | pid_t pid; | |
c71a8961 | 199 | int cpu, pc = 0; |
18cea459 | 200 | bool blk_tracer = blk_tracer_enabled; |
2056a782 | 201 | |
18cea459 | 202 | if (unlikely(bt->trace_state != Blktrace_running && !blk_tracer)) |
2056a782 JA |
203 | return; |
204 | ||
205 | what |= ddir_act[rw & WRITE]; | |
7b6d91da CH |
206 | what |= MASK_TC_BIT(rw, SYNC); |
207 | what |= MASK_TC_BIT(rw, RAHEAD); | |
35ba8f70 DW |
208 | what |= MASK_TC_BIT(rw, META); |
209 | what |= MASK_TC_BIT(rw, DISCARD); | |
c09c47ca NK |
210 | what |= MASK_TC_BIT(rw, FLUSH); |
211 | what |= MASK_TC_BIT(rw, FUA); | |
2056a782 JA |
212 | |
213 | pid = tsk->pid; | |
d0deef5b | 214 | if (act_log_check(bt, what, sector, pid)) |
2056a782 | 215 | return; |
c71a8961 ACM |
216 | cpu = raw_smp_processor_id(); |
217 | ||
18cea459 | 218 | if (blk_tracer) { |
c71a8961 ACM |
219 | tracing_record_cmdline(current); |
220 | ||
e77405ad | 221 | buffer = blk_tr->buffer; |
51a763dd | 222 | pc = preempt_count(); |
e77405ad | 223 | event = trace_buffer_lock_reserve(buffer, TRACE_BLK, |
51a763dd ACM |
224 | sizeof(*t) + pdu_len, |
225 | 0, pc); | |
c71a8961 ACM |
226 | if (!event) |
227 | return; | |
51a763dd | 228 | t = ring_buffer_event_data(event); |
c71a8961 ACM |
229 | goto record_it; |
230 | } | |
2056a782 JA |
231 | |
232 | /* | |
233 | * A word about the locking here - we disable interrupts to reserve | |
234 | * some space in the relay per-cpu buffer, to prevent an irq | |
14a73f54 | 235 | * from coming in and stepping on our toes. |
2056a782 JA |
236 | */ |
237 | local_irq_save(flags); | |
238 | ||
239 | if (unlikely(tsk->btrace_seq != blktrace_seq)) | |
240 | trace_note_tsk(bt, tsk); | |
241 | ||
242 | t = relay_reserve(bt->rchan, sizeof(*t) + pdu_len); | |
243 | if (t) { | |
2056a782 JA |
244 | sequence = per_cpu_ptr(bt->sequence, cpu); |
245 | ||
246 | t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; | |
247 | t->sequence = ++(*sequence); | |
2997c8c4 | 248 | t->time = ktime_to_ns(ktime_get()); |
c71a8961 | 249 | record_it: |
08a06b83 | 250 | /* |
939b3669 ACM |
251 | * These two are not needed in ftrace as they are in the |
252 | * generic trace_entry, filled by tracing_generic_entry_update, | |
253 | * but for the trace_event->bin() synthesizer benefit we do it | |
254 | * here too. | |
255 | */ | |
256 | t->cpu = cpu; | |
257 | t->pid = pid; | |
08a06b83 | 258 | |
2056a782 JA |
259 | t->sector = sector; |
260 | t->bytes = bytes; | |
261 | t->action = what; | |
2056a782 | 262 | t->device = bt->dev; |
2056a782 JA |
263 | t->error = error; |
264 | t->pdu_len = pdu_len; | |
265 | ||
266 | if (pdu_len) | |
267 | memcpy((void *) t + sizeof(*t), pdu_data, pdu_len); | |
c71a8961 | 268 | |
18cea459 | 269 | if (blk_tracer) { |
e77405ad | 270 | trace_buffer_unlock_commit(buffer, event, 0, pc); |
c71a8961 ACM |
271 | return; |
272 | } | |
2056a782 JA |
273 | } |
274 | ||
275 | local_irq_restore(flags); | |
276 | } | |
277 | ||
2056a782 | 278 | static struct dentry *blk_tree_root; |
11a57153 | 279 | static DEFINE_MUTEX(blk_tree_mutex); |
2056a782 | 280 | |
ad5dd549 | 281 | static void blk_trace_free(struct blk_trace *bt) |
2056a782 | 282 | { |
02c62304 | 283 | debugfs_remove(bt->msg_file); |
2056a782 | 284 | debugfs_remove(bt->dropped_file); |
f48fc4d3 | 285 | relay_close(bt->rchan); |
39cbb602 | 286 | debugfs_remove(bt->dir); |
2056a782 | 287 | free_percpu(bt->sequence); |
64565911 | 288 | free_percpu(bt->msg_data); |
2056a782 | 289 | kfree(bt); |
ad5dd549 LZ |
290 | } |
291 | ||
292 | static void blk_trace_cleanup(struct blk_trace *bt) | |
293 | { | |
294 | blk_trace_free(bt); | |
5f3ea37c ACM |
295 | if (atomic_dec_and_test(&blk_probes_ref)) |
296 | blk_unregister_tracepoints(); | |
2056a782 JA |
297 | } |
298 | ||
6da127ad | 299 | int blk_trace_remove(struct request_queue *q) |
2056a782 JA |
300 | { |
301 | struct blk_trace *bt; | |
302 | ||
303 | bt = xchg(&q->blk_trace, NULL); | |
304 | if (!bt) | |
305 | return -EINVAL; | |
306 | ||
55547204 | 307 | if (bt->trace_state != Blktrace_running) |
2056a782 JA |
308 | blk_trace_cleanup(bt); |
309 | ||
310 | return 0; | |
311 | } | |
6da127ad | 312 | EXPORT_SYMBOL_GPL(blk_trace_remove); |
2056a782 | 313 | |
2056a782 JA |
314 | static ssize_t blk_dropped_read(struct file *filp, char __user *buffer, |
315 | size_t count, loff_t *ppos) | |
316 | { | |
317 | struct blk_trace *bt = filp->private_data; | |
318 | char buf[16]; | |
319 | ||
320 | snprintf(buf, sizeof(buf), "%u\n", atomic_read(&bt->dropped)); | |
321 | ||
322 | return simple_read_from_buffer(buffer, count, ppos, buf, strlen(buf)); | |
323 | } | |
324 | ||
2b8693c0 | 325 | static const struct file_operations blk_dropped_fops = { |
2056a782 | 326 | .owner = THIS_MODULE, |
234e3405 | 327 | .open = simple_open, |
2056a782 | 328 | .read = blk_dropped_read, |
6038f373 | 329 | .llseek = default_llseek, |
2056a782 JA |
330 | }; |
331 | ||
02c62304 AB |
332 | static ssize_t blk_msg_write(struct file *filp, const char __user *buffer, |
333 | size_t count, loff_t *ppos) | |
334 | { | |
335 | char *msg; | |
336 | struct blk_trace *bt; | |
337 | ||
7635b03a | 338 | if (count >= BLK_TN_MAX_MSG) |
02c62304 AB |
339 | return -EINVAL; |
340 | ||
a4b3ada8 | 341 | msg = kmalloc(count + 1, GFP_KERNEL); |
02c62304 AB |
342 | if (msg == NULL) |
343 | return -ENOMEM; | |
344 | ||
345 | if (copy_from_user(msg, buffer, count)) { | |
346 | kfree(msg); | |
347 | return -EFAULT; | |
348 | } | |
349 | ||
a4b3ada8 | 350 | msg[count] = '\0'; |
02c62304 AB |
351 | bt = filp->private_data; |
352 | __trace_note_message(bt, "%s", msg); | |
353 | kfree(msg); | |
354 | ||
355 | return count; | |
356 | } | |
357 | ||
358 | static const struct file_operations blk_msg_fops = { | |
359 | .owner = THIS_MODULE, | |
234e3405 | 360 | .open = simple_open, |
02c62304 | 361 | .write = blk_msg_write, |
6038f373 | 362 | .llseek = noop_llseek, |
02c62304 AB |
363 | }; |
364 | ||
2056a782 JA |
365 | /* |
366 | * Keep track of how many times we encountered a full subbuffer, to aid | |
367 | * the user space app in telling how many lost events there were. | |
368 | */ | |
369 | static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf, | |
370 | void *prev_subbuf, size_t prev_padding) | |
371 | { | |
372 | struct blk_trace *bt; | |
373 | ||
374 | if (!relay_buf_full(buf)) | |
375 | return 1; | |
376 | ||
377 | bt = buf->chan->private_data; | |
378 | atomic_inc(&bt->dropped); | |
379 | return 0; | |
380 | } | |
381 | ||
382 | static int blk_remove_buf_file_callback(struct dentry *dentry) | |
383 | { | |
384 | debugfs_remove(dentry); | |
f48fc4d3 | 385 | |
2056a782 JA |
386 | return 0; |
387 | } | |
388 | ||
389 | static struct dentry *blk_create_buf_file_callback(const char *filename, | |
390 | struct dentry *parent, | |
f4ae40a6 | 391 | umode_t mode, |
2056a782 JA |
392 | struct rchan_buf *buf, |
393 | int *is_global) | |
394 | { | |
395 | return debugfs_create_file(filename, mode, parent, buf, | |
396 | &relay_file_operations); | |
397 | } | |
398 | ||
399 | static struct rchan_callbacks blk_relay_callbacks = { | |
400 | .subbuf_start = blk_subbuf_start_callback, | |
401 | .create_buf_file = blk_create_buf_file_callback, | |
402 | .remove_buf_file = blk_remove_buf_file_callback, | |
403 | }; | |
404 | ||
9908c309 LZ |
405 | static void blk_trace_setup_lba(struct blk_trace *bt, |
406 | struct block_device *bdev) | |
407 | { | |
408 | struct hd_struct *part = NULL; | |
409 | ||
410 | if (bdev) | |
411 | part = bdev->bd_part; | |
412 | ||
413 | if (part) { | |
414 | bt->start_lba = part->start_sect; | |
415 | bt->end_lba = part->start_sect + part->nr_sects; | |
416 | } else { | |
417 | bt->start_lba = 0; | |
418 | bt->end_lba = -1ULL; | |
419 | } | |
420 | } | |
421 | ||
2056a782 JA |
422 | /* |
423 | * Setup everything required to start tracing | |
424 | */ | |
6da127ad | 425 | int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, |
d0deef5b SD |
426 | struct block_device *bdev, |
427 | struct blk_user_trace_setup *buts) | |
2056a782 | 428 | { |
2056a782 JA |
429 | struct blk_trace *old_bt, *bt = NULL; |
430 | struct dentry *dir = NULL; | |
2056a782 JA |
431 | int ret, i; |
432 | ||
171044d4 | 433 | if (!buts->buf_size || !buts->buf_nr) |
2056a782 JA |
434 | return -EINVAL; |
435 | ||
0497b345 JA |
436 | strncpy(buts->name, name, BLKTRACE_BDEV_SIZE); |
437 | buts->name[BLKTRACE_BDEV_SIZE - 1] = '\0'; | |
2056a782 JA |
438 | |
439 | /* | |
440 | * some device names have larger paths - convert the slashes | |
441 | * to underscores for this to work as expected | |
442 | */ | |
171044d4 AB |
443 | for (i = 0; i < strlen(buts->name); i++) |
444 | if (buts->name[i] == '/') | |
445 | buts->name[i] = '_'; | |
2056a782 | 446 | |
2056a782 JA |
447 | bt = kzalloc(sizeof(*bt), GFP_KERNEL); |
448 | if (!bt) | |
ad5dd549 | 449 | return -ENOMEM; |
2056a782 | 450 | |
ad5dd549 | 451 | ret = -ENOMEM; |
2056a782 JA |
452 | bt->sequence = alloc_percpu(unsigned long); |
453 | if (!bt->sequence) | |
454 | goto err; | |
455 | ||
313e458f | 456 | bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); |
64565911 JA |
457 | if (!bt->msg_data) |
458 | goto err; | |
459 | ||
2056a782 | 460 | ret = -ENOENT; |
f48fc4d3 | 461 | |
b5230b56 | 462 | mutex_lock(&blk_tree_mutex); |
f48fc4d3 JA |
463 | if (!blk_tree_root) { |
464 | blk_tree_root = debugfs_create_dir("block", NULL); | |
b5230b56 LZ |
465 | if (!blk_tree_root) { |
466 | mutex_unlock(&blk_tree_mutex); | |
1a17662e | 467 | goto err; |
b5230b56 | 468 | } |
f48fc4d3 | 469 | } |
b5230b56 | 470 | mutex_unlock(&blk_tree_mutex); |
f48fc4d3 JA |
471 | |
472 | dir = debugfs_create_dir(buts->name, blk_tree_root); | |
473 | ||
2056a782 JA |
474 | if (!dir) |
475 | goto err; | |
476 | ||
477 | bt->dir = dir; | |
6da127ad | 478 | bt->dev = dev; |
2056a782 JA |
479 | atomic_set(&bt->dropped, 0); |
480 | ||
481 | ret = -EIO; | |
939b3669 ACM |
482 | bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt, |
483 | &blk_dropped_fops); | |
2056a782 JA |
484 | if (!bt->dropped_file) |
485 | goto err; | |
486 | ||
02c62304 AB |
487 | bt->msg_file = debugfs_create_file("msg", 0222, dir, bt, &blk_msg_fops); |
488 | if (!bt->msg_file) | |
489 | goto err; | |
490 | ||
171044d4 AB |
491 | bt->rchan = relay_open("trace", dir, buts->buf_size, |
492 | buts->buf_nr, &blk_relay_callbacks, bt); | |
2056a782 JA |
493 | if (!bt->rchan) |
494 | goto err; | |
2056a782 | 495 | |
171044d4 | 496 | bt->act_mask = buts->act_mask; |
2056a782 JA |
497 | if (!bt->act_mask) |
498 | bt->act_mask = (u16) -1; | |
499 | ||
9908c309 | 500 | blk_trace_setup_lba(bt, bdev); |
2056a782 | 501 | |
d0deef5b SD |
502 | /* overwrite with user settings */ |
503 | if (buts->start_lba) | |
504 | bt->start_lba = buts->start_lba; | |
505 | if (buts->end_lba) | |
506 | bt->end_lba = buts->end_lba; | |
507 | ||
171044d4 | 508 | bt->pid = buts->pid; |
2056a782 JA |
509 | bt->trace_state = Blktrace_setup; |
510 | ||
511 | ret = -EBUSY; | |
512 | old_bt = xchg(&q->blk_trace, bt); | |
513 | if (old_bt) { | |
514 | (void) xchg(&q->blk_trace, old_bt); | |
515 | goto err; | |
516 | } | |
517 | ||
17ba97e3 | 518 | if (atomic_inc_return(&blk_probes_ref) == 1) |
cbe28296 LZ |
519 | blk_register_tracepoints(); |
520 | ||
2056a782 JA |
521 | return 0; |
522 | err: | |
ad5dd549 | 523 | blk_trace_free(bt); |
2056a782 JA |
524 | return ret; |
525 | } | |
171044d4 | 526 | |
6da127ad | 527 | int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, |
d0deef5b | 528 | struct block_device *bdev, |
6da127ad | 529 | char __user *arg) |
171044d4 AB |
530 | { |
531 | struct blk_user_trace_setup buts; | |
532 | int ret; | |
533 | ||
534 | ret = copy_from_user(&buts, arg, sizeof(buts)); | |
535 | if (ret) | |
536 | return -EFAULT; | |
537 | ||
d0deef5b | 538 | ret = do_blk_trace_setup(q, name, dev, bdev, &buts); |
171044d4 AB |
539 | if (ret) |
540 | return ret; | |
541 | ||
9a8c28c8 DM |
542 | if (copy_to_user(arg, &buts, sizeof(buts))) { |
543 | blk_trace_remove(q); | |
171044d4 | 544 | return -EFAULT; |
9a8c28c8 | 545 | } |
171044d4 AB |
546 | return 0; |
547 | } | |
6da127ad | 548 | EXPORT_SYMBOL_GPL(blk_trace_setup); |
2056a782 | 549 | |
62c2a7d9 AB |
550 | #if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64) |
551 | static int compat_blk_trace_setup(struct request_queue *q, char *name, | |
552 | dev_t dev, struct block_device *bdev, | |
553 | char __user *arg) | |
554 | { | |
555 | struct blk_user_trace_setup buts; | |
556 | struct compat_blk_user_trace_setup cbuts; | |
557 | int ret; | |
558 | ||
559 | if (copy_from_user(&cbuts, arg, sizeof(cbuts))) | |
560 | return -EFAULT; | |
561 | ||
562 | buts = (struct blk_user_trace_setup) { | |
563 | .act_mask = cbuts.act_mask, | |
564 | .buf_size = cbuts.buf_size, | |
565 | .buf_nr = cbuts.buf_nr, | |
566 | .start_lba = cbuts.start_lba, | |
567 | .end_lba = cbuts.end_lba, | |
568 | .pid = cbuts.pid, | |
569 | }; | |
570 | memcpy(&buts.name, &cbuts.name, 32); | |
571 | ||
572 | ret = do_blk_trace_setup(q, name, dev, bdev, &buts); | |
573 | if (ret) | |
574 | return ret; | |
575 | ||
576 | if (copy_to_user(arg, &buts.name, 32)) { | |
577 | blk_trace_remove(q); | |
578 | return -EFAULT; | |
579 | } | |
580 | ||
581 | return 0; | |
582 | } | |
583 | #endif | |
584 | ||
6da127ad | 585 | int blk_trace_startstop(struct request_queue *q, int start) |
2056a782 | 586 | { |
2056a782 | 587 | int ret; |
939b3669 | 588 | struct blk_trace *bt = q->blk_trace; |
2056a782 | 589 | |
939b3669 | 590 | if (bt == NULL) |
2056a782 JA |
591 | return -EINVAL; |
592 | ||
593 | /* | |
594 | * For starting a trace, we can transition from a setup or stopped | |
595 | * trace. For stopping a trace, the state must be running | |
596 | */ | |
597 | ret = -EINVAL; | |
598 | if (start) { | |
599 | if (bt->trace_state == Blktrace_setup || | |
600 | bt->trace_state == Blktrace_stopped) { | |
601 | blktrace_seq++; | |
602 | smp_mb(); | |
603 | bt->trace_state = Blktrace_running; | |
be1c6341 OK |
604 | |
605 | trace_note_time(bt); | |
2056a782 JA |
606 | ret = 0; |
607 | } | |
608 | } else { | |
609 | if (bt->trace_state == Blktrace_running) { | |
610 | bt->trace_state = Blktrace_stopped; | |
611 | relay_flush(bt->rchan); | |
612 | ret = 0; | |
613 | } | |
614 | } | |
615 | ||
616 | return ret; | |
617 | } | |
6da127ad | 618 | EXPORT_SYMBOL_GPL(blk_trace_startstop); |
2056a782 JA |
619 | |
620 | /** | |
621 | * blk_trace_ioctl: - handle the ioctls associated with tracing | |
622 | * @bdev: the block device | |
ef18012b | 623 | * @cmd: the ioctl cmd |
2056a782 JA |
624 | * @arg: the argument data, if any |
625 | * | |
626 | **/ | |
627 | int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) | |
628 | { | |
165125e1 | 629 | struct request_queue *q; |
2056a782 | 630 | int ret, start = 0; |
6da127ad | 631 | char b[BDEVNAME_SIZE]; |
2056a782 JA |
632 | |
633 | q = bdev_get_queue(bdev); | |
634 | if (!q) | |
635 | return -ENXIO; | |
636 | ||
637 | mutex_lock(&bdev->bd_mutex); | |
638 | ||
639 | switch (cmd) { | |
640 | case BLKTRACESETUP: | |
f36f21ec | 641 | bdevname(bdev, b); |
d0deef5b | 642 | ret = blk_trace_setup(q, b, bdev->bd_dev, bdev, arg); |
2056a782 | 643 | break; |
62c2a7d9 AB |
644 | #if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64) |
645 | case BLKTRACESETUP32: | |
646 | bdevname(bdev, b); | |
647 | ret = compat_blk_trace_setup(q, b, bdev->bd_dev, bdev, arg); | |
648 | break; | |
649 | #endif | |
2056a782 JA |
650 | case BLKTRACESTART: |
651 | start = 1; | |
652 | case BLKTRACESTOP: | |
653 | ret = blk_trace_startstop(q, start); | |
654 | break; | |
655 | case BLKTRACETEARDOWN: | |
656 | ret = blk_trace_remove(q); | |
657 | break; | |
658 | default: | |
659 | ret = -ENOTTY; | |
660 | break; | |
661 | } | |
662 | ||
663 | mutex_unlock(&bdev->bd_mutex); | |
664 | return ret; | |
665 | } | |
666 | ||
667 | /** | |
668 | * blk_trace_shutdown: - stop and cleanup trace structures | |
669 | * @q: the request queue associated with the device | |
670 | * | |
671 | **/ | |
165125e1 | 672 | void blk_trace_shutdown(struct request_queue *q) |
2056a782 | 673 | { |
6c5c9341 AD |
674 | if (q->blk_trace) { |
675 | blk_trace_startstop(q, 0); | |
676 | blk_trace_remove(q); | |
677 | } | |
2056a782 | 678 | } |
5f3ea37c ACM |
679 | |
680 | /* | |
681 | * blktrace probes | |
682 | */ | |
683 | ||
684 | /** | |
685 | * blk_add_trace_rq - Add a trace for a request oriented action | |
686 | * @q: queue the io is for | |
687 | * @rq: the source request | |
688 | * @what: the action | |
689 | * | |
690 | * Description: | |
691 | * Records an action against a request. Will log the bio offset + size. | |
692 | * | |
693 | **/ | |
694 | static void blk_add_trace_rq(struct request_queue *q, struct request *rq, | |
805f6b5e | 695 | u32 what) |
5f3ea37c ACM |
696 | { |
697 | struct blk_trace *bt = q->blk_trace; | |
5f3ea37c ACM |
698 | |
699 | if (likely(!bt)) | |
700 | return; | |
701 | ||
33659ebb | 702 | if (rq->cmd_type == REQ_TYPE_BLOCK_PC) { |
5f3ea37c | 703 | what |= BLK_TC_ACT(BLK_TC_PC); |
805f6b5e | 704 | __blk_add_trace(bt, 0, blk_rq_bytes(rq), rq->cmd_flags, |
2e46e8b2 | 705 | what, rq->errors, rq->cmd_len, rq->cmd); |
5f3ea37c ACM |
706 | } else { |
707 | what |= BLK_TC_ACT(BLK_TC_FS); | |
805f6b5e TM |
708 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), |
709 | rq->cmd_flags, what, rq->errors, 0, NULL); | |
5f3ea37c ACM |
710 | } |
711 | } | |
712 | ||
38516ab5 SR |
713 | static void blk_add_trace_rq_abort(void *ignore, |
714 | struct request_queue *q, struct request *rq) | |
5f3ea37c ACM |
715 | { |
716 | blk_add_trace_rq(q, rq, BLK_TA_ABORT); | |
717 | } | |
718 | ||
38516ab5 SR |
719 | static void blk_add_trace_rq_insert(void *ignore, |
720 | struct request_queue *q, struct request *rq) | |
5f3ea37c ACM |
721 | { |
722 | blk_add_trace_rq(q, rq, BLK_TA_INSERT); | |
723 | } | |
724 | ||
38516ab5 SR |
725 | static void blk_add_trace_rq_issue(void *ignore, |
726 | struct request_queue *q, struct request *rq) | |
5f3ea37c ACM |
727 | { |
728 | blk_add_trace_rq(q, rq, BLK_TA_ISSUE); | |
729 | } | |
730 | ||
38516ab5 SR |
731 | static void blk_add_trace_rq_requeue(void *ignore, |
732 | struct request_queue *q, | |
939b3669 | 733 | struct request *rq) |
5f3ea37c ACM |
734 | { |
735 | blk_add_trace_rq(q, rq, BLK_TA_REQUEUE); | |
736 | } | |
737 | ||
38516ab5 SR |
738 | static void blk_add_trace_rq_complete(void *ignore, |
739 | struct request_queue *q, | |
939b3669 | 740 | struct request *rq) |
5f3ea37c ACM |
741 | { |
742 | blk_add_trace_rq(q, rq, BLK_TA_COMPLETE); | |
743 | } | |
744 | ||
745 | /** | |
746 | * blk_add_trace_bio - Add a trace for a bio oriented action | |
747 | * @q: queue the io is for | |
748 | * @bio: the source bio | |
749 | * @what: the action | |
797a455d | 750 | * @error: error, if any |
5f3ea37c ACM |
751 | * |
752 | * Description: | |
753 | * Records an action against a bio. Will log the bio offset + size. | |
754 | * | |
755 | **/ | |
756 | static void blk_add_trace_bio(struct request_queue *q, struct bio *bio, | |
797a455d | 757 | u32 what, int error) |
5f3ea37c ACM |
758 | { |
759 | struct blk_trace *bt = q->blk_trace; | |
760 | ||
761 | if (likely(!bt)) | |
762 | return; | |
763 | ||
797a455d JA |
764 | if (!error && !bio_flagged(bio, BIO_UPTODATE)) |
765 | error = EIO; | |
766 | ||
5f3ea37c | 767 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, |
797a455d | 768 | error, 0, NULL); |
5f3ea37c ACM |
769 | } |
770 | ||
38516ab5 SR |
771 | static void blk_add_trace_bio_bounce(void *ignore, |
772 | struct request_queue *q, struct bio *bio) | |
5f3ea37c | 773 | { |
797a455d | 774 | blk_add_trace_bio(q, bio, BLK_TA_BOUNCE, 0); |
5f3ea37c ACM |
775 | } |
776 | ||
38516ab5 | 777 | static void blk_add_trace_bio_complete(void *ignore, |
23036f1a MD |
778 | struct request_queue *q, struct bio *bio, |
779 | int error) | |
5f3ea37c | 780 | { |
797a455d | 781 | blk_add_trace_bio(q, bio, BLK_TA_COMPLETE, error); |
5f3ea37c ACM |
782 | } |
783 | ||
38516ab5 SR |
784 | static void blk_add_trace_bio_backmerge(void *ignore, |
785 | struct request_queue *q, | |
939b3669 | 786 | struct bio *bio) |
5f3ea37c | 787 | { |
797a455d | 788 | blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE, 0); |
5f3ea37c ACM |
789 | } |
790 | ||
38516ab5 SR |
791 | static void blk_add_trace_bio_frontmerge(void *ignore, |
792 | struct request_queue *q, | |
939b3669 | 793 | struct bio *bio) |
5f3ea37c | 794 | { |
797a455d | 795 | blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE, 0); |
5f3ea37c ACM |
796 | } |
797 | ||
38516ab5 SR |
798 | static void blk_add_trace_bio_queue(void *ignore, |
799 | struct request_queue *q, struct bio *bio) | |
5f3ea37c | 800 | { |
797a455d | 801 | blk_add_trace_bio(q, bio, BLK_TA_QUEUE, 0); |
5f3ea37c ACM |
802 | } |
803 | ||
38516ab5 SR |
804 | static void blk_add_trace_getrq(void *ignore, |
805 | struct request_queue *q, | |
939b3669 | 806 | struct bio *bio, int rw) |
5f3ea37c ACM |
807 | { |
808 | if (bio) | |
797a455d | 809 | blk_add_trace_bio(q, bio, BLK_TA_GETRQ, 0); |
5f3ea37c ACM |
810 | else { |
811 | struct blk_trace *bt = q->blk_trace; | |
812 | ||
813 | if (bt) | |
814 | __blk_add_trace(bt, 0, 0, rw, BLK_TA_GETRQ, 0, 0, NULL); | |
815 | } | |
816 | } | |
817 | ||
818 | ||
38516ab5 SR |
819 | static void blk_add_trace_sleeprq(void *ignore, |
820 | struct request_queue *q, | |
939b3669 | 821 | struct bio *bio, int rw) |
5f3ea37c ACM |
822 | { |
823 | if (bio) | |
797a455d | 824 | blk_add_trace_bio(q, bio, BLK_TA_SLEEPRQ, 0); |
5f3ea37c ACM |
825 | else { |
826 | struct blk_trace *bt = q->blk_trace; | |
827 | ||
828 | if (bt) | |
939b3669 ACM |
829 | __blk_add_trace(bt, 0, 0, rw, BLK_TA_SLEEPRQ, |
830 | 0, 0, NULL); | |
5f3ea37c ACM |
831 | } |
832 | } | |
833 | ||
38516ab5 | 834 | static void blk_add_trace_plug(void *ignore, struct request_queue *q) |
5f3ea37c ACM |
835 | { |
836 | struct blk_trace *bt = q->blk_trace; | |
837 | ||
838 | if (bt) | |
839 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_PLUG, 0, 0, NULL); | |
840 | } | |
841 | ||
49cac01e JA |
842 | static void blk_add_trace_unplug(void *ignore, struct request_queue *q, |
843 | unsigned int depth, bool explicit) | |
5f3ea37c ACM |
844 | { |
845 | struct blk_trace *bt = q->blk_trace; | |
846 | ||
847 | if (bt) { | |
94b5eb28 | 848 | __be64 rpdu = cpu_to_be64(depth); |
49cac01e | 849 | u32 what; |
5f3ea37c | 850 | |
49cac01e JA |
851 | if (explicit) |
852 | what = BLK_TA_UNPLUG_IO; | |
853 | else | |
854 | what = BLK_TA_UNPLUG_TIMER; | |
855 | ||
856 | __blk_add_trace(bt, 0, 0, 0, what, 0, sizeof(rpdu), &rpdu); | |
5f3ea37c ACM |
857 | } |
858 | } | |
859 | ||
38516ab5 SR |
860 | static void blk_add_trace_split(void *ignore, |
861 | struct request_queue *q, struct bio *bio, | |
5f3ea37c ACM |
862 | unsigned int pdu) |
863 | { | |
864 | struct blk_trace *bt = q->blk_trace; | |
865 | ||
866 | if (bt) { | |
867 | __be64 rpdu = cpu_to_be64(pdu); | |
868 | ||
869 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, | |
870 | BLK_TA_SPLIT, !bio_flagged(bio, BIO_UPTODATE), | |
871 | sizeof(rpdu), &rpdu); | |
872 | } | |
873 | } | |
874 | ||
875 | /** | |
d07335e5 | 876 | * blk_add_trace_bio_remap - Add a trace for a bio-remap operation |
546cf44a | 877 | * @ignore: trace callback data parameter (not used) |
5f3ea37c ACM |
878 | * @q: queue the io is for |
879 | * @bio: the source bio | |
880 | * @dev: target device | |
a42aaa3b | 881 | * @from: source sector |
5f3ea37c ACM |
882 | * |
883 | * Description: | |
884 | * Device mapper or raid target sometimes need to split a bio because | |
885 | * it spans a stripe (or similar). Add a trace for that action. | |
886 | * | |
887 | **/ | |
d07335e5 MS |
888 | static void blk_add_trace_bio_remap(void *ignore, |
889 | struct request_queue *q, struct bio *bio, | |
890 | dev_t dev, sector_t from) | |
5f3ea37c ACM |
891 | { |
892 | struct blk_trace *bt = q->blk_trace; | |
893 | struct blk_io_trace_remap r; | |
894 | ||
895 | if (likely(!bt)) | |
896 | return; | |
897 | ||
a42aaa3b AB |
898 | r.device_from = cpu_to_be32(dev); |
899 | r.device_to = cpu_to_be32(bio->bi_bdev->bd_dev); | |
900 | r.sector_from = cpu_to_be64(from); | |
5f3ea37c | 901 | |
22a7c31a AB |
902 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, |
903 | BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), | |
904 | sizeof(r), &r); | |
5f3ea37c ACM |
905 | } |
906 | ||
b0da3f0d JN |
907 | /** |
908 | * blk_add_trace_rq_remap - Add a trace for a request-remap operation | |
546cf44a | 909 | * @ignore: trace callback data parameter (not used) |
b0da3f0d JN |
910 | * @q: queue the io is for |
911 | * @rq: the source request | |
912 | * @dev: target device | |
913 | * @from: source sector | |
914 | * | |
915 | * Description: | |
916 | * Device mapper remaps request to other devices. | |
917 | * Add a trace for that action. | |
918 | * | |
919 | **/ | |
38516ab5 SR |
920 | static void blk_add_trace_rq_remap(void *ignore, |
921 | struct request_queue *q, | |
b0da3f0d JN |
922 | struct request *rq, dev_t dev, |
923 | sector_t from) | |
924 | { | |
925 | struct blk_trace *bt = q->blk_trace; | |
926 | struct blk_io_trace_remap r; | |
927 | ||
928 | if (likely(!bt)) | |
929 | return; | |
930 | ||
931 | r.device_from = cpu_to_be32(dev); | |
932 | r.device_to = cpu_to_be32(disk_devt(rq->rq_disk)); | |
933 | r.sector_from = cpu_to_be64(from); | |
934 | ||
935 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), | |
936 | rq_data_dir(rq), BLK_TA_REMAP, !!rq->errors, | |
937 | sizeof(r), &r); | |
938 | } | |
939 | ||
5f3ea37c ACM |
940 | /** |
941 | * blk_add_driver_data - Add binary message with driver-specific data | |
942 | * @q: queue the io is for | |
943 | * @rq: io request | |
944 | * @data: driver-specific data | |
945 | * @len: length of driver-specific data | |
946 | * | |
947 | * Description: | |
948 | * Some drivers might want to write driver-specific data per request. | |
949 | * | |
950 | **/ | |
951 | void blk_add_driver_data(struct request_queue *q, | |
952 | struct request *rq, | |
953 | void *data, size_t len) | |
954 | { | |
955 | struct blk_trace *bt = q->blk_trace; | |
956 | ||
957 | if (likely(!bt)) | |
958 | return; | |
959 | ||
33659ebb | 960 | if (rq->cmd_type == REQ_TYPE_BLOCK_PC) |
2e46e8b2 TH |
961 | __blk_add_trace(bt, 0, blk_rq_bytes(rq), 0, |
962 | BLK_TA_DRV_DATA, rq->errors, len, data); | |
5f3ea37c | 963 | else |
2e46e8b2 TH |
964 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), 0, |
965 | BLK_TA_DRV_DATA, rq->errors, len, data); | |
5f3ea37c ACM |
966 | } |
967 | EXPORT_SYMBOL_GPL(blk_add_driver_data); | |
968 | ||
3c289ba7 | 969 | static void blk_register_tracepoints(void) |
5f3ea37c ACM |
970 | { |
971 | int ret; | |
972 | ||
38516ab5 | 973 | ret = register_trace_block_rq_abort(blk_add_trace_rq_abort, NULL); |
5f3ea37c | 974 | WARN_ON(ret); |
38516ab5 | 975 | ret = register_trace_block_rq_insert(blk_add_trace_rq_insert, NULL); |
5f3ea37c | 976 | WARN_ON(ret); |
38516ab5 | 977 | ret = register_trace_block_rq_issue(blk_add_trace_rq_issue, NULL); |
5f3ea37c | 978 | WARN_ON(ret); |
38516ab5 | 979 | ret = register_trace_block_rq_requeue(blk_add_trace_rq_requeue, NULL); |
5f3ea37c | 980 | WARN_ON(ret); |
38516ab5 | 981 | ret = register_trace_block_rq_complete(blk_add_trace_rq_complete, NULL); |
5f3ea37c | 982 | WARN_ON(ret); |
38516ab5 | 983 | ret = register_trace_block_bio_bounce(blk_add_trace_bio_bounce, NULL); |
5f3ea37c | 984 | WARN_ON(ret); |
38516ab5 | 985 | ret = register_trace_block_bio_complete(blk_add_trace_bio_complete, NULL); |
5f3ea37c | 986 | WARN_ON(ret); |
38516ab5 | 987 | ret = register_trace_block_bio_backmerge(blk_add_trace_bio_backmerge, NULL); |
5f3ea37c | 988 | WARN_ON(ret); |
38516ab5 | 989 | ret = register_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge, NULL); |
5f3ea37c | 990 | WARN_ON(ret); |
38516ab5 | 991 | ret = register_trace_block_bio_queue(blk_add_trace_bio_queue, NULL); |
5f3ea37c | 992 | WARN_ON(ret); |
38516ab5 | 993 | ret = register_trace_block_getrq(blk_add_trace_getrq, NULL); |
5f3ea37c | 994 | WARN_ON(ret); |
38516ab5 | 995 | ret = register_trace_block_sleeprq(blk_add_trace_sleeprq, NULL); |
5f3ea37c | 996 | WARN_ON(ret); |
38516ab5 | 997 | ret = register_trace_block_plug(blk_add_trace_plug, NULL); |
5f3ea37c | 998 | WARN_ON(ret); |
49cac01e | 999 | ret = register_trace_block_unplug(blk_add_trace_unplug, NULL); |
5f3ea37c | 1000 | WARN_ON(ret); |
38516ab5 | 1001 | ret = register_trace_block_split(blk_add_trace_split, NULL); |
5f3ea37c | 1002 | WARN_ON(ret); |
d07335e5 | 1003 | ret = register_trace_block_bio_remap(blk_add_trace_bio_remap, NULL); |
5f3ea37c | 1004 | WARN_ON(ret); |
38516ab5 | 1005 | ret = register_trace_block_rq_remap(blk_add_trace_rq_remap, NULL); |
b0da3f0d | 1006 | WARN_ON(ret); |
5f3ea37c ACM |
1007 | } |
1008 | ||
1009 | static void blk_unregister_tracepoints(void) | |
1010 | { | |
38516ab5 | 1011 | unregister_trace_block_rq_remap(blk_add_trace_rq_remap, NULL); |
d07335e5 | 1012 | unregister_trace_block_bio_remap(blk_add_trace_bio_remap, NULL); |
38516ab5 | 1013 | unregister_trace_block_split(blk_add_trace_split, NULL); |
49cac01e | 1014 | unregister_trace_block_unplug(blk_add_trace_unplug, NULL); |
38516ab5 SR |
1015 | unregister_trace_block_plug(blk_add_trace_plug, NULL); |
1016 | unregister_trace_block_sleeprq(blk_add_trace_sleeprq, NULL); | |
1017 | unregister_trace_block_getrq(blk_add_trace_getrq, NULL); | |
1018 | unregister_trace_block_bio_queue(blk_add_trace_bio_queue, NULL); | |
1019 | unregister_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge, NULL); | |
1020 | unregister_trace_block_bio_backmerge(blk_add_trace_bio_backmerge, NULL); | |
1021 | unregister_trace_block_bio_complete(blk_add_trace_bio_complete, NULL); | |
1022 | unregister_trace_block_bio_bounce(blk_add_trace_bio_bounce, NULL); | |
1023 | unregister_trace_block_rq_complete(blk_add_trace_rq_complete, NULL); | |
1024 | unregister_trace_block_rq_requeue(blk_add_trace_rq_requeue, NULL); | |
1025 | unregister_trace_block_rq_issue(blk_add_trace_rq_issue, NULL); | |
1026 | unregister_trace_block_rq_insert(blk_add_trace_rq_insert, NULL); | |
1027 | unregister_trace_block_rq_abort(blk_add_trace_rq_abort, NULL); | |
5f3ea37c ACM |
1028 | |
1029 | tracepoint_synchronize_unregister(); | |
1030 | } | |
c71a8961 ACM |
1031 | |
1032 | /* | |
1033 | * struct blk_io_tracer formatting routines | |
1034 | */ | |
1035 | ||
1036 | static void fill_rwbs(char *rwbs, const struct blk_io_trace *t) | |
1037 | { | |
157f9c00 | 1038 | int i = 0; |
65796348 | 1039 | int tc = t->action >> BLK_TC_SHIFT; |
157f9c00 | 1040 | |
18cea459 LZ |
1041 | if (t->action == BLK_TN_MESSAGE) { |
1042 | rwbs[i++] = 'N'; | |
1043 | goto out; | |
1044 | } | |
1045 | ||
c09c47ca NK |
1046 | if (tc & BLK_TC_FLUSH) |
1047 | rwbs[i++] = 'F'; | |
1048 | ||
65796348 | 1049 | if (tc & BLK_TC_DISCARD) |
157f9c00 | 1050 | rwbs[i++] = 'D'; |
65796348 | 1051 | else if (tc & BLK_TC_WRITE) |
157f9c00 ACM |
1052 | rwbs[i++] = 'W'; |
1053 | else if (t->bytes) | |
1054 | rwbs[i++] = 'R'; | |
1055 | else | |
1056 | rwbs[i++] = 'N'; | |
1057 | ||
c09c47ca NK |
1058 | if (tc & BLK_TC_FUA) |
1059 | rwbs[i++] = 'F'; | |
65796348 | 1060 | if (tc & BLK_TC_AHEAD) |
157f9c00 | 1061 | rwbs[i++] = 'A'; |
65796348 | 1062 | if (tc & BLK_TC_SYNC) |
157f9c00 | 1063 | rwbs[i++] = 'S'; |
65796348 | 1064 | if (tc & BLK_TC_META) |
157f9c00 | 1065 | rwbs[i++] = 'M'; |
18cea459 | 1066 | out: |
157f9c00 | 1067 | rwbs[i] = '\0'; |
c71a8961 ACM |
1068 | } |
1069 | ||
1070 | static inline | |
1071 | const struct blk_io_trace *te_blk_io_trace(const struct trace_entry *ent) | |
1072 | { | |
1073 | return (const struct blk_io_trace *)ent; | |
1074 | } | |
1075 | ||
1076 | static inline const void *pdu_start(const struct trace_entry *ent) | |
1077 | { | |
1078 | return te_blk_io_trace(ent) + 1; | |
1079 | } | |
1080 | ||
66de7792 LZ |
1081 | static inline u32 t_action(const struct trace_entry *ent) |
1082 | { | |
1083 | return te_blk_io_trace(ent)->action; | |
1084 | } | |
1085 | ||
1086 | static inline u32 t_bytes(const struct trace_entry *ent) | |
1087 | { | |
1088 | return te_blk_io_trace(ent)->bytes; | |
1089 | } | |
1090 | ||
c71a8961 ACM |
1091 | static inline u32 t_sec(const struct trace_entry *ent) |
1092 | { | |
1093 | return te_blk_io_trace(ent)->bytes >> 9; | |
1094 | } | |
1095 | ||
1096 | static inline unsigned long long t_sector(const struct trace_entry *ent) | |
1097 | { | |
1098 | return te_blk_io_trace(ent)->sector; | |
1099 | } | |
1100 | ||
1101 | static inline __u16 t_error(const struct trace_entry *ent) | |
1102 | { | |
e0dc81be | 1103 | return te_blk_io_trace(ent)->error; |
c71a8961 ACM |
1104 | } |
1105 | ||
1106 | static __u64 get_pdu_int(const struct trace_entry *ent) | |
1107 | { | |
1108 | const __u64 *val = pdu_start(ent); | |
1109 | return be64_to_cpu(*val); | |
1110 | } | |
1111 | ||
1112 | static void get_pdu_remap(const struct trace_entry *ent, | |
1113 | struct blk_io_trace_remap *r) | |
1114 | { | |
1115 | const struct blk_io_trace_remap *__r = pdu_start(ent); | |
a42aaa3b | 1116 | __u64 sector_from = __r->sector_from; |
c71a8961 | 1117 | |
c71a8961 | 1118 | r->device_from = be32_to_cpu(__r->device_from); |
a42aaa3b AB |
1119 | r->device_to = be32_to_cpu(__r->device_to); |
1120 | r->sector_from = be64_to_cpu(sector_from); | |
c71a8961 ACM |
1121 | } |
1122 | ||
b6a4b0c3 LZ |
1123 | typedef int (blk_log_action_t) (struct trace_iterator *iter, const char *act); |
1124 | ||
1125 | static int blk_log_action_classic(struct trace_iterator *iter, const char *act) | |
c71a8961 | 1126 | { |
c09c47ca | 1127 | char rwbs[RWBS_LEN]; |
35ac51bf LZ |
1128 | unsigned long long ts = iter->ts; |
1129 | unsigned long nsec_rem = do_div(ts, NSEC_PER_SEC); | |
c71a8961 | 1130 | unsigned secs = (unsigned long)ts; |
b6a4b0c3 | 1131 | const struct blk_io_trace *t = te_blk_io_trace(iter->ent); |
c71a8961 ACM |
1132 | |
1133 | fill_rwbs(rwbs, t); | |
1134 | ||
1135 | return trace_seq_printf(&iter->seq, | |
35ac51bf | 1136 | "%3d,%-3d %2d %5d.%09lu %5u %2s %3s ", |
c71a8961 | 1137 | MAJOR(t->device), MINOR(t->device), iter->cpu, |
b6a4b0c3 | 1138 | secs, nsec_rem, iter->ent->pid, act, rwbs); |
c71a8961 ACM |
1139 | } |
1140 | ||
b6a4b0c3 | 1141 | static int blk_log_action(struct trace_iterator *iter, const char *act) |
c71a8961 | 1142 | { |
c09c47ca | 1143 | char rwbs[RWBS_LEN]; |
b6a4b0c3 LZ |
1144 | const struct blk_io_trace *t = te_blk_io_trace(iter->ent); |
1145 | ||
c71a8961 | 1146 | fill_rwbs(rwbs, t); |
b6a4b0c3 | 1147 | return trace_seq_printf(&iter->seq, "%3d,%-3d %2s %3s ", |
c71a8961 ACM |
1148 | MAJOR(t->device), MINOR(t->device), act, rwbs); |
1149 | } | |
1150 | ||
66de7792 LZ |
1151 | static int blk_log_dump_pdu(struct trace_seq *s, const struct trace_entry *ent) |
1152 | { | |
04986257 | 1153 | const unsigned char *pdu_buf; |
66de7792 LZ |
1154 | int pdu_len; |
1155 | int i, end, ret; | |
1156 | ||
1157 | pdu_buf = pdu_start(ent); | |
1158 | pdu_len = te_blk_io_trace(ent)->pdu_len; | |
1159 | ||
1160 | if (!pdu_len) | |
1161 | return 1; | |
1162 | ||
1163 | /* find the last zero that needs to be printed */ | |
1164 | for (end = pdu_len - 1; end >= 0; end--) | |
1165 | if (pdu_buf[end]) | |
1166 | break; | |
1167 | end++; | |
1168 | ||
1169 | if (!trace_seq_putc(s, '(')) | |
1170 | return 0; | |
1171 | ||
1172 | for (i = 0; i < pdu_len; i++) { | |
1173 | ||
1174 | ret = trace_seq_printf(s, "%s%02x", | |
1175 | i == 0 ? "" : " ", pdu_buf[i]); | |
1176 | if (!ret) | |
1177 | return ret; | |
1178 | ||
1179 | /* | |
1180 | * stop when the rest is just zeroes and indicate so | |
1181 | * with a ".." appended | |
1182 | */ | |
1183 | if (i == end && end != pdu_len - 1) | |
1184 | return trace_seq_puts(s, " ..) "); | |
1185 | } | |
1186 | ||
1187 | return trace_seq_puts(s, ") "); | |
1188 | } | |
1189 | ||
c71a8961 ACM |
1190 | static int blk_log_generic(struct trace_seq *s, const struct trace_entry *ent) |
1191 | { | |
4ca53085 SR |
1192 | char cmd[TASK_COMM_LEN]; |
1193 | ||
1194 | trace_find_cmdline(ent->pid, cmd); | |
c71a8961 | 1195 | |
66de7792 LZ |
1196 | if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { |
1197 | int ret; | |
1198 | ||
1199 | ret = trace_seq_printf(s, "%u ", t_bytes(ent)); | |
1200 | if (!ret) | |
1201 | return 0; | |
1202 | ret = blk_log_dump_pdu(s, ent); | |
1203 | if (!ret) | |
1204 | return 0; | |
1205 | return trace_seq_printf(s, "[%s]\n", cmd); | |
1206 | } else { | |
1207 | if (t_sec(ent)) | |
1208 | return trace_seq_printf(s, "%llu + %u [%s]\n", | |
1209 | t_sector(ent), t_sec(ent), cmd); | |
1210 | return trace_seq_printf(s, "[%s]\n", cmd); | |
1211 | } | |
c71a8961 ACM |
1212 | } |
1213 | ||
157f9c00 ACM |
1214 | static int blk_log_with_error(struct trace_seq *s, |
1215 | const struct trace_entry *ent) | |
c71a8961 | 1216 | { |
66de7792 LZ |
1217 | if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { |
1218 | int ret; | |
1219 | ||
1220 | ret = blk_log_dump_pdu(s, ent); | |
1221 | if (ret) | |
1222 | return trace_seq_printf(s, "[%d]\n", t_error(ent)); | |
1223 | return 0; | |
1224 | } else { | |
1225 | if (t_sec(ent)) | |
1226 | return trace_seq_printf(s, "%llu + %u [%d]\n", | |
1227 | t_sector(ent), | |
1228 | t_sec(ent), t_error(ent)); | |
1229 | return trace_seq_printf(s, "%llu [%d]\n", | |
1230 | t_sector(ent), t_error(ent)); | |
1231 | } | |
c71a8961 ACM |
1232 | } |
1233 | ||
1234 | static int blk_log_remap(struct trace_seq *s, const struct trace_entry *ent) | |
1235 | { | |
a42aaa3b | 1236 | struct blk_io_trace_remap r = { .device_from = 0, }; |
c71a8961 ACM |
1237 | |
1238 | get_pdu_remap(ent, &r); | |
1239 | return trace_seq_printf(s, "%llu + %u <- (%d,%d) %llu\n", | |
a42aaa3b AB |
1240 | t_sector(ent), t_sec(ent), |
1241 | MAJOR(r.device_from), MINOR(r.device_from), | |
1242 | (unsigned long long)r.sector_from); | |
c71a8961 ACM |
1243 | } |
1244 | ||
1245 | static int blk_log_plug(struct trace_seq *s, const struct trace_entry *ent) | |
1246 | { | |
4ca53085 SR |
1247 | char cmd[TASK_COMM_LEN]; |
1248 | ||
1249 | trace_find_cmdline(ent->pid, cmd); | |
1250 | ||
1251 | return trace_seq_printf(s, "[%s]\n", cmd); | |
c71a8961 ACM |
1252 | } |
1253 | ||
1254 | static int blk_log_unplug(struct trace_seq *s, const struct trace_entry *ent) | |
1255 | { | |
4ca53085 SR |
1256 | char cmd[TASK_COMM_LEN]; |
1257 | ||
1258 | trace_find_cmdline(ent->pid, cmd); | |
1259 | ||
1260 | return trace_seq_printf(s, "[%s] %llu\n", cmd, get_pdu_int(ent)); | |
c71a8961 ACM |
1261 | } |
1262 | ||
1263 | static int blk_log_split(struct trace_seq *s, const struct trace_entry *ent) | |
1264 | { | |
4ca53085 SR |
1265 | char cmd[TASK_COMM_LEN]; |
1266 | ||
1267 | trace_find_cmdline(ent->pid, cmd); | |
1268 | ||
c71a8961 | 1269 | return trace_seq_printf(s, "%llu / %llu [%s]\n", t_sector(ent), |
4ca53085 | 1270 | get_pdu_int(ent), cmd); |
c71a8961 ACM |
1271 | } |
1272 | ||
18cea459 LZ |
1273 | static int blk_log_msg(struct trace_seq *s, const struct trace_entry *ent) |
1274 | { | |
1275 | int ret; | |
1276 | const struct blk_io_trace *t = te_blk_io_trace(ent); | |
1277 | ||
1278 | ret = trace_seq_putmem(s, t + 1, t->pdu_len); | |
1279 | if (ret) | |
1280 | return trace_seq_putc(s, '\n'); | |
1281 | return ret; | |
1282 | } | |
1283 | ||
c71a8961 ACM |
1284 | /* |
1285 | * struct tracer operations | |
1286 | */ | |
1287 | ||
1288 | static void blk_tracer_print_header(struct seq_file *m) | |
1289 | { | |
1290 | if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) | |
1291 | return; | |
1292 | seq_puts(m, "# DEV CPU TIMESTAMP PID ACT FLG\n" | |
1293 | "# | | | | | |\n"); | |
1294 | } | |
1295 | ||
1296 | static void blk_tracer_start(struct trace_array *tr) | |
1297 | { | |
ad5dd549 | 1298 | blk_tracer_enabled = true; |
c71a8961 ACM |
1299 | } |
1300 | ||
1301 | static int blk_tracer_init(struct trace_array *tr) | |
1302 | { | |
1303 | blk_tr = tr; | |
1304 | blk_tracer_start(tr); | |
c71a8961 ACM |
1305 | return 0; |
1306 | } | |
1307 | ||
1308 | static void blk_tracer_stop(struct trace_array *tr) | |
1309 | { | |
ad5dd549 | 1310 | blk_tracer_enabled = false; |
c71a8961 ACM |
1311 | } |
1312 | ||
1313 | static void blk_tracer_reset(struct trace_array *tr) | |
1314 | { | |
c71a8961 ACM |
1315 | blk_tracer_stop(tr); |
1316 | } | |
1317 | ||
e4955c99 | 1318 | static const struct { |
c71a8961 | 1319 | const char *act[2]; |
ef18012b | 1320 | int (*print)(struct trace_seq *s, const struct trace_entry *ent); |
e4955c99 | 1321 | } what2act[] = { |
ef18012b | 1322 | [__BLK_TA_QUEUE] = {{ "Q", "queue" }, blk_log_generic }, |
c71a8961 ACM |
1323 | [__BLK_TA_BACKMERGE] = {{ "M", "backmerge" }, blk_log_generic }, |
1324 | [__BLK_TA_FRONTMERGE] = {{ "F", "frontmerge" }, blk_log_generic }, | |
1325 | [__BLK_TA_GETRQ] = {{ "G", "getrq" }, blk_log_generic }, | |
1326 | [__BLK_TA_SLEEPRQ] = {{ "S", "sleeprq" }, blk_log_generic }, | |
1327 | [__BLK_TA_REQUEUE] = {{ "R", "requeue" }, blk_log_with_error }, | |
1328 | [__BLK_TA_ISSUE] = {{ "D", "issue" }, blk_log_generic }, | |
1329 | [__BLK_TA_COMPLETE] = {{ "C", "complete" }, blk_log_with_error }, | |
1330 | [__BLK_TA_PLUG] = {{ "P", "plug" }, blk_log_plug }, | |
1331 | [__BLK_TA_UNPLUG_IO] = {{ "U", "unplug_io" }, blk_log_unplug }, | |
49cac01e | 1332 | [__BLK_TA_UNPLUG_TIMER] = {{ "UT", "unplug_timer" }, blk_log_unplug }, |
c71a8961 ACM |
1333 | [__BLK_TA_INSERT] = {{ "I", "insert" }, blk_log_generic }, |
1334 | [__BLK_TA_SPLIT] = {{ "X", "split" }, blk_log_split }, | |
1335 | [__BLK_TA_BOUNCE] = {{ "B", "bounce" }, blk_log_generic }, | |
1336 | [__BLK_TA_REMAP] = {{ "A", "remap" }, blk_log_remap }, | |
1337 | }; | |
1338 | ||
b6a4b0c3 LZ |
1339 | static enum print_line_t print_one_line(struct trace_iterator *iter, |
1340 | bool classic) | |
c71a8961 | 1341 | { |
2c9b238e | 1342 | struct trace_seq *s = &iter->seq; |
b6a4b0c3 LZ |
1343 | const struct blk_io_trace *t; |
1344 | u16 what; | |
c71a8961 | 1345 | int ret; |
b6a4b0c3 LZ |
1346 | bool long_act; |
1347 | blk_log_action_t *log_action; | |
c71a8961 | 1348 | |
b6a4b0c3 LZ |
1349 | t = te_blk_io_trace(iter->ent); |
1350 | what = t->action & ((1 << BLK_TC_SHIFT) - 1); | |
1351 | long_act = !!(trace_flags & TRACE_ITER_VERBOSE); | |
1352 | log_action = classic ? &blk_log_action_classic : &blk_log_action; | |
08a06b83 | 1353 | |
18cea459 LZ |
1354 | if (t->action == BLK_TN_MESSAGE) { |
1355 | ret = log_action(iter, long_act ? "message" : "m"); | |
1356 | if (ret) | |
1357 | ret = blk_log_msg(s, iter->ent); | |
1358 | goto out; | |
1359 | } | |
1360 | ||
eb08f8eb | 1361 | if (unlikely(what == 0 || what >= ARRAY_SIZE(what2act))) |
b78825d6 | 1362 | ret = trace_seq_printf(s, "Unknown action %x\n", what); |
c71a8961 | 1363 | else { |
b6a4b0c3 | 1364 | ret = log_action(iter, what2act[what].act[long_act]); |
c71a8961 | 1365 | if (ret) |
2c9b238e | 1366 | ret = what2act[what].print(s, iter->ent); |
c71a8961 | 1367 | } |
18cea459 | 1368 | out: |
c71a8961 ACM |
1369 | return ret ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; |
1370 | } | |
1371 | ||
b6a4b0c3 | 1372 | static enum print_line_t blk_trace_event_print(struct trace_iterator *iter, |
a9a57763 | 1373 | int flags, struct trace_event *event) |
b6a4b0c3 | 1374 | { |
b6a4b0c3 LZ |
1375 | return print_one_line(iter, false); |
1376 | } | |
1377 | ||
08a06b83 ACM |
1378 | static int blk_trace_synthesize_old_trace(struct trace_iterator *iter) |
1379 | { | |
1380 | struct trace_seq *s = &iter->seq; | |
1381 | struct blk_io_trace *t = (struct blk_io_trace *)iter->ent; | |
1382 | const int offset = offsetof(struct blk_io_trace, sector); | |
1383 | struct blk_io_trace old = { | |
1384 | .magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION, | |
6c051ce0 | 1385 | .time = iter->ts, |
08a06b83 ACM |
1386 | }; |
1387 | ||
1388 | if (!trace_seq_putmem(s, &old, offset)) | |
1389 | return 0; | |
1390 | return trace_seq_putmem(s, &t->sector, | |
1391 | sizeof(old) - offset + t->pdu_len); | |
1392 | } | |
1393 | ||
ae7462b4 | 1394 | static enum print_line_t |
a9a57763 SR |
1395 | blk_trace_event_print_binary(struct trace_iterator *iter, int flags, |
1396 | struct trace_event *event) | |
08a06b83 ACM |
1397 | { |
1398 | return blk_trace_synthesize_old_trace(iter) ? | |
1399 | TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; | |
1400 | } | |
1401 | ||
c71a8961 ACM |
1402 | static enum print_line_t blk_tracer_print_line(struct trace_iterator *iter) |
1403 | { | |
c71a8961 ACM |
1404 | if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) |
1405 | return TRACE_TYPE_UNHANDLED; | |
1406 | ||
b6a4b0c3 | 1407 | return print_one_line(iter, true); |
c71a8961 ACM |
1408 | } |
1409 | ||
f3948f88 LZ |
1410 | static int blk_tracer_set_flag(u32 old_flags, u32 bit, int set) |
1411 | { | |
1412 | /* don't output context-info for blk_classic output */ | |
1413 | if (bit == TRACE_BLK_OPT_CLASSIC) { | |
1414 | if (set) | |
1415 | trace_flags &= ~TRACE_ITER_CONTEXT_INFO; | |
1416 | else | |
1417 | trace_flags |= TRACE_ITER_CONTEXT_INFO; | |
1418 | } | |
1419 | return 0; | |
1420 | } | |
1421 | ||
c71a8961 ACM |
1422 | static struct tracer blk_tracer __read_mostly = { |
1423 | .name = "blk", | |
1424 | .init = blk_tracer_init, | |
1425 | .reset = blk_tracer_reset, | |
1426 | .start = blk_tracer_start, | |
1427 | .stop = blk_tracer_stop, | |
1428 | .print_header = blk_tracer_print_header, | |
1429 | .print_line = blk_tracer_print_line, | |
1430 | .flags = &blk_tracer_flags, | |
f3948f88 | 1431 | .set_flag = blk_tracer_set_flag, |
c71a8961 ACM |
1432 | }; |
1433 | ||
a9a57763 | 1434 | static struct trace_event_functions trace_blk_event_funcs = { |
c71a8961 | 1435 | .trace = blk_trace_event_print, |
08a06b83 | 1436 | .binary = blk_trace_event_print_binary, |
c71a8961 ACM |
1437 | }; |
1438 | ||
a9a57763 SR |
1439 | static struct trace_event trace_blk_event = { |
1440 | .type = TRACE_BLK, | |
1441 | .funcs = &trace_blk_event_funcs, | |
1442 | }; | |
1443 | ||
c71a8961 ACM |
1444 | static int __init init_blk_tracer(void) |
1445 | { | |
1446 | if (!register_ftrace_event(&trace_blk_event)) { | |
1447 | pr_warning("Warning: could not register block events\n"); | |
1448 | return 1; | |
1449 | } | |
1450 | ||
1451 | if (register_tracer(&blk_tracer) != 0) { | |
1452 | pr_warning("Warning: could not register the block tracer\n"); | |
1453 | unregister_ftrace_event(&trace_blk_event); | |
1454 | return 1; | |
1455 | } | |
1456 | ||
1457 | return 0; | |
1458 | } | |
1459 | ||
1460 | device_initcall(init_blk_tracer); | |
1461 | ||
1462 | static int blk_trace_remove_queue(struct request_queue *q) | |
1463 | { | |
1464 | struct blk_trace *bt; | |
1465 | ||
1466 | bt = xchg(&q->blk_trace, NULL); | |
1467 | if (bt == NULL) | |
1468 | return -EINVAL; | |
1469 | ||
17ba97e3 LZ |
1470 | if (atomic_dec_and_test(&blk_probes_ref)) |
1471 | blk_unregister_tracepoints(); | |
1472 | ||
ad5dd549 | 1473 | blk_trace_free(bt); |
c71a8961 ACM |
1474 | return 0; |
1475 | } | |
1476 | ||
1477 | /* | |
1478 | * Setup everything required to start tracing | |
1479 | */ | |
9908c309 LZ |
1480 | static int blk_trace_setup_queue(struct request_queue *q, |
1481 | struct block_device *bdev) | |
c71a8961 ACM |
1482 | { |
1483 | struct blk_trace *old_bt, *bt = NULL; | |
18cea459 | 1484 | int ret = -ENOMEM; |
c71a8961 | 1485 | |
c71a8961 ACM |
1486 | bt = kzalloc(sizeof(*bt), GFP_KERNEL); |
1487 | if (!bt) | |
15152e44 | 1488 | return -ENOMEM; |
c71a8961 | 1489 | |
18cea459 LZ |
1490 | bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); |
1491 | if (!bt->msg_data) | |
1492 | goto free_bt; | |
1493 | ||
9908c309 | 1494 | bt->dev = bdev->bd_dev; |
c71a8961 | 1495 | bt->act_mask = (u16)-1; |
9908c309 LZ |
1496 | |
1497 | blk_trace_setup_lba(bt, bdev); | |
c71a8961 ACM |
1498 | |
1499 | old_bt = xchg(&q->blk_trace, bt); | |
1500 | if (old_bt != NULL) { | |
1501 | (void)xchg(&q->blk_trace, old_bt); | |
18cea459 LZ |
1502 | ret = -EBUSY; |
1503 | goto free_bt; | |
c71a8961 | 1504 | } |
15152e44 | 1505 | |
17ba97e3 LZ |
1506 | if (atomic_inc_return(&blk_probes_ref) == 1) |
1507 | blk_register_tracepoints(); | |
c71a8961 | 1508 | return 0; |
18cea459 LZ |
1509 | |
1510 | free_bt: | |
1511 | blk_trace_free(bt); | |
1512 | return ret; | |
c71a8961 ACM |
1513 | } |
1514 | ||
1515 | /* | |
1516 | * sysfs interface to enable and configure tracing | |
1517 | */ | |
1518 | ||
c71a8961 ACM |
1519 | static ssize_t sysfs_blk_trace_attr_show(struct device *dev, |
1520 | struct device_attribute *attr, | |
1521 | char *buf); | |
1522 | static ssize_t sysfs_blk_trace_attr_store(struct device *dev, | |
1523 | struct device_attribute *attr, | |
1524 | const char *buf, size_t count); | |
1525 | #define BLK_TRACE_DEVICE_ATTR(_name) \ | |
1526 | DEVICE_ATTR(_name, S_IRUGO | S_IWUSR, \ | |
1527 | sysfs_blk_trace_attr_show, \ | |
1528 | sysfs_blk_trace_attr_store) | |
1529 | ||
cd649b8b | 1530 | static BLK_TRACE_DEVICE_ATTR(enable); |
c71a8961 ACM |
1531 | static BLK_TRACE_DEVICE_ATTR(act_mask); |
1532 | static BLK_TRACE_DEVICE_ATTR(pid); | |
1533 | static BLK_TRACE_DEVICE_ATTR(start_lba); | |
1534 | static BLK_TRACE_DEVICE_ATTR(end_lba); | |
1535 | ||
1536 | static struct attribute *blk_trace_attrs[] = { | |
1537 | &dev_attr_enable.attr, | |
1538 | &dev_attr_act_mask.attr, | |
1539 | &dev_attr_pid.attr, | |
1540 | &dev_attr_start_lba.attr, | |
1541 | &dev_attr_end_lba.attr, | |
1542 | NULL | |
1543 | }; | |
1544 | ||
1545 | struct attribute_group blk_trace_attr_group = { | |
1546 | .name = "trace", | |
1547 | .attrs = blk_trace_attrs, | |
1548 | }; | |
1549 | ||
09341997 LZ |
1550 | static const struct { |
1551 | int mask; | |
1552 | const char *str; | |
1553 | } mask_maps[] = { | |
1554 | { BLK_TC_READ, "read" }, | |
1555 | { BLK_TC_WRITE, "write" }, | |
c09c47ca | 1556 | { BLK_TC_FLUSH, "flush" }, |
09341997 LZ |
1557 | { BLK_TC_SYNC, "sync" }, |
1558 | { BLK_TC_QUEUE, "queue" }, | |
1559 | { BLK_TC_REQUEUE, "requeue" }, | |
1560 | { BLK_TC_ISSUE, "issue" }, | |
1561 | { BLK_TC_COMPLETE, "complete" }, | |
1562 | { BLK_TC_FS, "fs" }, | |
1563 | { BLK_TC_PC, "pc" }, | |
1564 | { BLK_TC_AHEAD, "ahead" }, | |
1565 | { BLK_TC_META, "meta" }, | |
1566 | { BLK_TC_DISCARD, "discard" }, | |
1567 | { BLK_TC_DRV_DATA, "drv_data" }, | |
c09c47ca | 1568 | { BLK_TC_FUA, "fua" }, |
09341997 LZ |
1569 | }; |
1570 | ||
1571 | static int blk_trace_str2mask(const char *str) | |
c71a8961 | 1572 | { |
09341997 | 1573 | int i; |
c71a8961 | 1574 | int mask = 0; |
9eb85125 | 1575 | char *buf, *s, *token; |
c71a8961 | 1576 | |
9eb85125 LZ |
1577 | buf = kstrdup(str, GFP_KERNEL); |
1578 | if (buf == NULL) | |
c71a8961 | 1579 | return -ENOMEM; |
9eb85125 | 1580 | s = strstrip(buf); |
c71a8961 ACM |
1581 | |
1582 | while (1) { | |
09341997 LZ |
1583 | token = strsep(&s, ","); |
1584 | if (token == NULL) | |
c71a8961 ACM |
1585 | break; |
1586 | ||
09341997 LZ |
1587 | if (*token == '\0') |
1588 | continue; | |
1589 | ||
1590 | for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { | |
1591 | if (strcasecmp(token, mask_maps[i].str) == 0) { | |
1592 | mask |= mask_maps[i].mask; | |
1593 | break; | |
1594 | } | |
1595 | } | |
1596 | if (i == ARRAY_SIZE(mask_maps)) { | |
1597 | mask = -EINVAL; | |
1598 | break; | |
1599 | } | |
c71a8961 | 1600 | } |
9eb85125 | 1601 | kfree(buf); |
c71a8961 ACM |
1602 | |
1603 | return mask; | |
1604 | } | |
1605 | ||
09341997 LZ |
1606 | static ssize_t blk_trace_mask2str(char *buf, int mask) |
1607 | { | |
1608 | int i; | |
1609 | char *p = buf; | |
1610 | ||
1611 | for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { | |
1612 | if (mask & mask_maps[i].mask) { | |
1613 | p += sprintf(p, "%s%s", | |
1614 | (p == buf) ? "" : ",", mask_maps[i].str); | |
1615 | } | |
1616 | } | |
1617 | *p++ = '\n'; | |
1618 | ||
1619 | return p - buf; | |
1620 | } | |
1621 | ||
b125130b LZ |
1622 | static struct request_queue *blk_trace_get_queue(struct block_device *bdev) |
1623 | { | |
1624 | if (bdev->bd_disk == NULL) | |
1625 | return NULL; | |
1626 | ||
1627 | return bdev_get_queue(bdev); | |
1628 | } | |
1629 | ||
c71a8961 ACM |
1630 | static ssize_t sysfs_blk_trace_attr_show(struct device *dev, |
1631 | struct device_attribute *attr, | |
1632 | char *buf) | |
1633 | { | |
1634 | struct hd_struct *p = dev_to_part(dev); | |
1635 | struct request_queue *q; | |
1636 | struct block_device *bdev; | |
1637 | ssize_t ret = -ENXIO; | |
1638 | ||
c71a8961 ACM |
1639 | bdev = bdget(part_devt(p)); |
1640 | if (bdev == NULL) | |
01b284f9 | 1641 | goto out; |
c71a8961 | 1642 | |
b125130b | 1643 | q = blk_trace_get_queue(bdev); |
c71a8961 ACM |
1644 | if (q == NULL) |
1645 | goto out_bdput; | |
b125130b | 1646 | |
c71a8961 | 1647 | mutex_lock(&bdev->bd_mutex); |
cd649b8b LZ |
1648 | |
1649 | if (attr == &dev_attr_enable) { | |
1650 | ret = sprintf(buf, "%u\n", !!q->blk_trace); | |
1651 | goto out_unlock_bdev; | |
1652 | } | |
1653 | ||
c71a8961 ACM |
1654 | if (q->blk_trace == NULL) |
1655 | ret = sprintf(buf, "disabled\n"); | |
1656 | else if (attr == &dev_attr_act_mask) | |
09341997 | 1657 | ret = blk_trace_mask2str(buf, q->blk_trace->act_mask); |
c71a8961 ACM |
1658 | else if (attr == &dev_attr_pid) |
1659 | ret = sprintf(buf, "%u\n", q->blk_trace->pid); | |
1660 | else if (attr == &dev_attr_start_lba) | |
1661 | ret = sprintf(buf, "%llu\n", q->blk_trace->start_lba); | |
1662 | else if (attr == &dev_attr_end_lba) | |
1663 | ret = sprintf(buf, "%llu\n", q->blk_trace->end_lba); | |
cd649b8b LZ |
1664 | |
1665 | out_unlock_bdev: | |
c71a8961 ACM |
1666 | mutex_unlock(&bdev->bd_mutex); |
1667 | out_bdput: | |
1668 | bdput(bdev); | |
01b284f9 | 1669 | out: |
c71a8961 ACM |
1670 | return ret; |
1671 | } | |
1672 | ||
1673 | static ssize_t sysfs_blk_trace_attr_store(struct device *dev, | |
1674 | struct device_attribute *attr, | |
1675 | const char *buf, size_t count) | |
1676 | { | |
1677 | struct block_device *bdev; | |
1678 | struct request_queue *q; | |
1679 | struct hd_struct *p; | |
1680 | u64 value; | |
09341997 | 1681 | ssize_t ret = -EINVAL; |
c71a8961 ACM |
1682 | |
1683 | if (count == 0) | |
1684 | goto out; | |
1685 | ||
1686 | if (attr == &dev_attr_act_mask) { | |
1687 | if (sscanf(buf, "%llx", &value) != 1) { | |
1688 | /* Assume it is a list of trace category names */ | |
09341997 LZ |
1689 | ret = blk_trace_str2mask(buf); |
1690 | if (ret < 0) | |
c71a8961 | 1691 | goto out; |
09341997 | 1692 | value = ret; |
c71a8961 ACM |
1693 | } |
1694 | } else if (sscanf(buf, "%llu", &value) != 1) | |
1695 | goto out; | |
1696 | ||
09341997 LZ |
1697 | ret = -ENXIO; |
1698 | ||
c71a8961 ACM |
1699 | p = dev_to_part(dev); |
1700 | bdev = bdget(part_devt(p)); | |
1701 | if (bdev == NULL) | |
01b284f9 | 1702 | goto out; |
c71a8961 | 1703 | |
b125130b | 1704 | q = blk_trace_get_queue(bdev); |
c71a8961 ACM |
1705 | if (q == NULL) |
1706 | goto out_bdput; | |
1707 | ||
1708 | mutex_lock(&bdev->bd_mutex); | |
cd649b8b LZ |
1709 | |
1710 | if (attr == &dev_attr_enable) { | |
1711 | if (value) | |
9908c309 | 1712 | ret = blk_trace_setup_queue(q, bdev); |
cd649b8b LZ |
1713 | else |
1714 | ret = blk_trace_remove_queue(q); | |
1715 | goto out_unlock_bdev; | |
1716 | } | |
1717 | ||
c71a8961 ACM |
1718 | ret = 0; |
1719 | if (q->blk_trace == NULL) | |
9908c309 | 1720 | ret = blk_trace_setup_queue(q, bdev); |
c71a8961 ACM |
1721 | |
1722 | if (ret == 0) { | |
1723 | if (attr == &dev_attr_act_mask) | |
1724 | q->blk_trace->act_mask = value; | |
1725 | else if (attr == &dev_attr_pid) | |
1726 | q->blk_trace->pid = value; | |
1727 | else if (attr == &dev_attr_start_lba) | |
1728 | q->blk_trace->start_lba = value; | |
1729 | else if (attr == &dev_attr_end_lba) | |
1730 | q->blk_trace->end_lba = value; | |
c71a8961 | 1731 | } |
cd649b8b LZ |
1732 | |
1733 | out_unlock_bdev: | |
c71a8961 ACM |
1734 | mutex_unlock(&bdev->bd_mutex); |
1735 | out_bdput: | |
1736 | bdput(bdev); | |
c71a8961 | 1737 | out: |
cd649b8b | 1738 | return ret ? ret : count; |
c71a8961 | 1739 | } |
cd649b8b | 1740 | |
1d54ad6d LZ |
1741 | int blk_trace_init_sysfs(struct device *dev) |
1742 | { | |
1743 | return sysfs_create_group(&dev->kobj, &blk_trace_attr_group); | |
1744 | } | |
1745 | ||
48c0d4d4 ZK |
1746 | void blk_trace_remove_sysfs(struct device *dev) |
1747 | { | |
1748 | sysfs_remove_group(&dev->kobj, &blk_trace_attr_group); | |
1749 | } | |
1750 | ||
55782138 LZ |
1751 | #endif /* CONFIG_BLK_DEV_IO_TRACE */ |
1752 | ||
1753 | #ifdef CONFIG_EVENT_TRACING | |
1754 | ||
1755 | void blk_dump_cmd(char *buf, struct request *rq) | |
1756 | { | |
1757 | int i, end; | |
1758 | int len = rq->cmd_len; | |
1759 | unsigned char *cmd = rq->cmd; | |
1760 | ||
33659ebb | 1761 | if (rq->cmd_type != REQ_TYPE_BLOCK_PC) { |
55782138 LZ |
1762 | buf[0] = '\0'; |
1763 | return; | |
1764 | } | |
1765 | ||
1766 | for (end = len - 1; end >= 0; end--) | |
1767 | if (cmd[end]) | |
1768 | break; | |
1769 | end++; | |
1770 | ||
1771 | for (i = 0; i < len; i++) { | |
1772 | buf += sprintf(buf, "%s%02x", i == 0 ? "" : " ", cmd[i]); | |
1773 | if (i == end && end != len - 1) { | |
1774 | sprintf(buf, " .."); | |
1775 | break; | |
1776 | } | |
1777 | } | |
1778 | } | |
1779 | ||
1780 | void blk_fill_rwbs(char *rwbs, u32 rw, int bytes) | |
1781 | { | |
1782 | int i = 0; | |
1783 | ||
c09c47ca NK |
1784 | if (rw & REQ_FLUSH) |
1785 | rwbs[i++] = 'F'; | |
1786 | ||
55782138 LZ |
1787 | if (rw & WRITE) |
1788 | rwbs[i++] = 'W'; | |
7b6d91da | 1789 | else if (rw & REQ_DISCARD) |
55782138 LZ |
1790 | rwbs[i++] = 'D'; |
1791 | else if (bytes) | |
1792 | rwbs[i++] = 'R'; | |
1793 | else | |
1794 | rwbs[i++] = 'N'; | |
1795 | ||
c09c47ca NK |
1796 | if (rw & REQ_FUA) |
1797 | rwbs[i++] = 'F'; | |
7b6d91da | 1798 | if (rw & REQ_RAHEAD) |
55782138 | 1799 | rwbs[i++] = 'A'; |
7b6d91da | 1800 | if (rw & REQ_SYNC) |
55782138 | 1801 | rwbs[i++] = 'S'; |
7b6d91da | 1802 | if (rw & REQ_META) |
55782138 | 1803 | rwbs[i++] = 'M'; |
8d57a98c AH |
1804 | if (rw & REQ_SECURE) |
1805 | rwbs[i++] = 'E'; | |
55782138 LZ |
1806 | |
1807 | rwbs[i] = '\0'; | |
1808 | } | |
1809 | ||
55782138 LZ |
1810 | #endif /* CONFIG_EVENT_TRACING */ |
1811 |