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Commit | Line | Data |
---|---|---|
2056a782 | 1 | /* |
0fe23479 | 2 | * Copyright (C) 2006 Jens Axboe <axboe@kernel.dk> |
2056a782 JA |
3 | * |
4 | * This program is free software; you can redistribute it and/or modify | |
5 | * it under the terms of the GNU General Public License version 2 as | |
6 | * published by the Free Software Foundation. | |
7 | * | |
8 | * This program is distributed in the hope that it will be useful, | |
9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
11 | * GNU General Public License for more details. | |
12 | * | |
13 | * You should have received a copy of the GNU General Public License | |
14 | * along with this program; if not, write to the Free Software | |
15 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
16 | * | |
17 | */ | |
2056a782 JA |
18 | #include <linux/kernel.h> |
19 | #include <linux/blkdev.h> | |
20 | #include <linux/blktrace_api.h> | |
21 | #include <linux/percpu.h> | |
22 | #include <linux/init.h> | |
23 | #include <linux/mutex.h> | |
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_RAHEAD BLK_TC_AHEAD |
172 | ||
35ba8f70 | 173 | /* The ilog2() calls fall out because they're constant */ |
7b6d91da CH |
174 | #define MASK_TC_BIT(rw, __name) ((rw & REQ_ ## __name) << \ |
175 | (ilog2(BLK_TC_ ## __name) + BLK_TC_SHIFT - __REQ_ ## __name)) | |
2056a782 JA |
176 | |
177 | /* | |
178 | * The worker for the various blk_add_trace*() types. Fills out a | |
179 | * blk_io_trace structure and places it in a per-cpu subbuffer. | |
180 | */ | |
5f3ea37c | 181 | static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, |
2056a782 JA |
182 | int rw, u32 what, int error, int pdu_len, void *pdu_data) |
183 | { | |
184 | struct task_struct *tsk = current; | |
c71a8961 | 185 | struct ring_buffer_event *event = NULL; |
e77405ad | 186 | struct ring_buffer *buffer = NULL; |
2056a782 | 187 | struct blk_io_trace *t; |
0a987751 | 188 | unsigned long flags = 0; |
2056a782 JA |
189 | unsigned long *sequence; |
190 | pid_t pid; | |
c71a8961 | 191 | int cpu, pc = 0; |
18cea459 | 192 | bool blk_tracer = blk_tracer_enabled; |
2056a782 | 193 | |
18cea459 | 194 | if (unlikely(bt->trace_state != Blktrace_running && !blk_tracer)) |
2056a782 JA |
195 | return; |
196 | ||
197 | what |= ddir_act[rw & WRITE]; | |
7b6d91da CH |
198 | what |= MASK_TC_BIT(rw, SYNC); |
199 | what |= MASK_TC_BIT(rw, RAHEAD); | |
35ba8f70 DW |
200 | what |= MASK_TC_BIT(rw, META); |
201 | what |= MASK_TC_BIT(rw, DISCARD); | |
2056a782 JA |
202 | |
203 | pid = tsk->pid; | |
d0deef5b | 204 | if (act_log_check(bt, what, sector, pid)) |
2056a782 | 205 | return; |
c71a8961 ACM |
206 | cpu = raw_smp_processor_id(); |
207 | ||
18cea459 | 208 | if (blk_tracer) { |
c71a8961 ACM |
209 | tracing_record_cmdline(current); |
210 | ||
e77405ad | 211 | buffer = blk_tr->buffer; |
51a763dd | 212 | pc = preempt_count(); |
e77405ad | 213 | event = trace_buffer_lock_reserve(buffer, TRACE_BLK, |
51a763dd ACM |
214 | sizeof(*t) + pdu_len, |
215 | 0, pc); | |
c71a8961 ACM |
216 | if (!event) |
217 | return; | |
51a763dd | 218 | t = ring_buffer_event_data(event); |
c71a8961 ACM |
219 | goto record_it; |
220 | } | |
2056a782 JA |
221 | |
222 | /* | |
223 | * A word about the locking here - we disable interrupts to reserve | |
224 | * some space in the relay per-cpu buffer, to prevent an irq | |
14a73f54 | 225 | * from coming in and stepping on our toes. |
2056a782 JA |
226 | */ |
227 | local_irq_save(flags); | |
228 | ||
229 | if (unlikely(tsk->btrace_seq != blktrace_seq)) | |
230 | trace_note_tsk(bt, tsk); | |
231 | ||
232 | t = relay_reserve(bt->rchan, sizeof(*t) + pdu_len); | |
233 | if (t) { | |
2056a782 JA |
234 | sequence = per_cpu_ptr(bt->sequence, cpu); |
235 | ||
236 | t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; | |
237 | t->sequence = ++(*sequence); | |
2997c8c4 | 238 | t->time = ktime_to_ns(ktime_get()); |
c71a8961 | 239 | record_it: |
08a06b83 | 240 | /* |
939b3669 ACM |
241 | * These two are not needed in ftrace as they are in the |
242 | * generic trace_entry, filled by tracing_generic_entry_update, | |
243 | * but for the trace_event->bin() synthesizer benefit we do it | |
244 | * here too. | |
245 | */ | |
246 | t->cpu = cpu; | |
247 | t->pid = pid; | |
08a06b83 | 248 | |
2056a782 JA |
249 | t->sector = sector; |
250 | t->bytes = bytes; | |
251 | t->action = what; | |
2056a782 | 252 | t->device = bt->dev; |
2056a782 JA |
253 | t->error = error; |
254 | t->pdu_len = pdu_len; | |
255 | ||
256 | if (pdu_len) | |
257 | memcpy((void *) t + sizeof(*t), pdu_data, pdu_len); | |
c71a8961 | 258 | |
18cea459 | 259 | if (blk_tracer) { |
e77405ad | 260 | trace_buffer_unlock_commit(buffer, event, 0, pc); |
c71a8961 ACM |
261 | return; |
262 | } | |
2056a782 JA |
263 | } |
264 | ||
265 | local_irq_restore(flags); | |
266 | } | |
267 | ||
2056a782 | 268 | static struct dentry *blk_tree_root; |
11a57153 | 269 | static DEFINE_MUTEX(blk_tree_mutex); |
2056a782 | 270 | |
ad5dd549 | 271 | static void blk_trace_free(struct blk_trace *bt) |
2056a782 | 272 | { |
02c62304 | 273 | debugfs_remove(bt->msg_file); |
2056a782 | 274 | debugfs_remove(bt->dropped_file); |
f48fc4d3 | 275 | relay_close(bt->rchan); |
39cbb602 | 276 | debugfs_remove(bt->dir); |
2056a782 | 277 | free_percpu(bt->sequence); |
64565911 | 278 | free_percpu(bt->msg_data); |
2056a782 | 279 | kfree(bt); |
ad5dd549 LZ |
280 | } |
281 | ||
282 | static void blk_trace_cleanup(struct blk_trace *bt) | |
283 | { | |
284 | blk_trace_free(bt); | |
5f3ea37c ACM |
285 | if (atomic_dec_and_test(&blk_probes_ref)) |
286 | blk_unregister_tracepoints(); | |
2056a782 JA |
287 | } |
288 | ||
6da127ad | 289 | int blk_trace_remove(struct request_queue *q) |
2056a782 JA |
290 | { |
291 | struct blk_trace *bt; | |
292 | ||
293 | bt = xchg(&q->blk_trace, NULL); | |
294 | if (!bt) | |
295 | return -EINVAL; | |
296 | ||
55547204 | 297 | if (bt->trace_state != Blktrace_running) |
2056a782 JA |
298 | blk_trace_cleanup(bt); |
299 | ||
300 | return 0; | |
301 | } | |
6da127ad | 302 | EXPORT_SYMBOL_GPL(blk_trace_remove); |
2056a782 JA |
303 | |
304 | static int blk_dropped_open(struct inode *inode, struct file *filp) | |
305 | { | |
8e18e294 | 306 | filp->private_data = inode->i_private; |
2056a782 JA |
307 | |
308 | return 0; | |
309 | } | |
310 | ||
311 | static ssize_t blk_dropped_read(struct file *filp, char __user *buffer, | |
312 | size_t count, loff_t *ppos) | |
313 | { | |
314 | struct blk_trace *bt = filp->private_data; | |
315 | char buf[16]; | |
316 | ||
317 | snprintf(buf, sizeof(buf), "%u\n", atomic_read(&bt->dropped)); | |
318 | ||
319 | return simple_read_from_buffer(buffer, count, ppos, buf, strlen(buf)); | |
320 | } | |
321 | ||
2b8693c0 | 322 | static const struct file_operations blk_dropped_fops = { |
2056a782 JA |
323 | .owner = THIS_MODULE, |
324 | .open = blk_dropped_open, | |
325 | .read = blk_dropped_read, | |
6038f373 | 326 | .llseek = default_llseek, |
2056a782 JA |
327 | }; |
328 | ||
02c62304 AB |
329 | static int blk_msg_open(struct inode *inode, struct file *filp) |
330 | { | |
331 | filp->private_data = inode->i_private; | |
332 | ||
333 | return 0; | |
334 | } | |
335 | ||
336 | static ssize_t blk_msg_write(struct file *filp, const char __user *buffer, | |
337 | size_t count, loff_t *ppos) | |
338 | { | |
339 | char *msg; | |
340 | struct blk_trace *bt; | |
341 | ||
7635b03a | 342 | if (count >= BLK_TN_MAX_MSG) |
02c62304 AB |
343 | return -EINVAL; |
344 | ||
a4b3ada8 | 345 | msg = kmalloc(count + 1, GFP_KERNEL); |
02c62304 AB |
346 | if (msg == NULL) |
347 | return -ENOMEM; | |
348 | ||
349 | if (copy_from_user(msg, buffer, count)) { | |
350 | kfree(msg); | |
351 | return -EFAULT; | |
352 | } | |
353 | ||
a4b3ada8 | 354 | msg[count] = '\0'; |
02c62304 AB |
355 | bt = filp->private_data; |
356 | __trace_note_message(bt, "%s", msg); | |
357 | kfree(msg); | |
358 | ||
359 | return count; | |
360 | } | |
361 | ||
362 | static const struct file_operations blk_msg_fops = { | |
363 | .owner = THIS_MODULE, | |
364 | .open = blk_msg_open, | |
365 | .write = blk_msg_write, | |
6038f373 | 366 | .llseek = noop_llseek, |
02c62304 AB |
367 | }; |
368 | ||
2056a782 JA |
369 | /* |
370 | * Keep track of how many times we encountered a full subbuffer, to aid | |
371 | * the user space app in telling how many lost events there were. | |
372 | */ | |
373 | static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf, | |
374 | void *prev_subbuf, size_t prev_padding) | |
375 | { | |
376 | struct blk_trace *bt; | |
377 | ||
378 | if (!relay_buf_full(buf)) | |
379 | return 1; | |
380 | ||
381 | bt = buf->chan->private_data; | |
382 | atomic_inc(&bt->dropped); | |
383 | return 0; | |
384 | } | |
385 | ||
386 | static int blk_remove_buf_file_callback(struct dentry *dentry) | |
387 | { | |
388 | debugfs_remove(dentry); | |
f48fc4d3 | 389 | |
2056a782 JA |
390 | return 0; |
391 | } | |
392 | ||
393 | static struct dentry *blk_create_buf_file_callback(const char *filename, | |
394 | struct dentry *parent, | |
395 | int mode, | |
396 | struct rchan_buf *buf, | |
397 | int *is_global) | |
398 | { | |
399 | return debugfs_create_file(filename, mode, parent, buf, | |
400 | &relay_file_operations); | |
401 | } | |
402 | ||
403 | static struct rchan_callbacks blk_relay_callbacks = { | |
404 | .subbuf_start = blk_subbuf_start_callback, | |
405 | .create_buf_file = blk_create_buf_file_callback, | |
406 | .remove_buf_file = blk_remove_buf_file_callback, | |
407 | }; | |
408 | ||
9908c309 LZ |
409 | static void blk_trace_setup_lba(struct blk_trace *bt, |
410 | struct block_device *bdev) | |
411 | { | |
412 | struct hd_struct *part = NULL; | |
413 | ||
414 | if (bdev) | |
415 | part = bdev->bd_part; | |
416 | ||
417 | if (part) { | |
418 | bt->start_lba = part->start_sect; | |
419 | bt->end_lba = part->start_sect + part->nr_sects; | |
420 | } else { | |
421 | bt->start_lba = 0; | |
422 | bt->end_lba = -1ULL; | |
423 | } | |
424 | } | |
425 | ||
2056a782 JA |
426 | /* |
427 | * Setup everything required to start tracing | |
428 | */ | |
6da127ad | 429 | int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, |
d0deef5b SD |
430 | struct block_device *bdev, |
431 | struct blk_user_trace_setup *buts) | |
2056a782 | 432 | { |
2056a782 JA |
433 | struct blk_trace *old_bt, *bt = NULL; |
434 | struct dentry *dir = NULL; | |
2056a782 JA |
435 | int ret, i; |
436 | ||
171044d4 | 437 | if (!buts->buf_size || !buts->buf_nr) |
2056a782 JA |
438 | return -EINVAL; |
439 | ||
0497b345 JA |
440 | strncpy(buts->name, name, BLKTRACE_BDEV_SIZE); |
441 | buts->name[BLKTRACE_BDEV_SIZE - 1] = '\0'; | |
2056a782 JA |
442 | |
443 | /* | |
444 | * some device names have larger paths - convert the slashes | |
445 | * to underscores for this to work as expected | |
446 | */ | |
171044d4 AB |
447 | for (i = 0; i < strlen(buts->name); i++) |
448 | if (buts->name[i] == '/') | |
449 | buts->name[i] = '_'; | |
2056a782 | 450 | |
2056a782 JA |
451 | bt = kzalloc(sizeof(*bt), GFP_KERNEL); |
452 | if (!bt) | |
ad5dd549 | 453 | return -ENOMEM; |
2056a782 | 454 | |
ad5dd549 | 455 | ret = -ENOMEM; |
2056a782 JA |
456 | bt->sequence = alloc_percpu(unsigned long); |
457 | if (!bt->sequence) | |
458 | goto err; | |
459 | ||
313e458f | 460 | bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); |
64565911 JA |
461 | if (!bt->msg_data) |
462 | goto err; | |
463 | ||
2056a782 | 464 | ret = -ENOENT; |
f48fc4d3 | 465 | |
b5230b56 | 466 | mutex_lock(&blk_tree_mutex); |
f48fc4d3 JA |
467 | if (!blk_tree_root) { |
468 | blk_tree_root = debugfs_create_dir("block", NULL); | |
b5230b56 LZ |
469 | if (!blk_tree_root) { |
470 | mutex_unlock(&blk_tree_mutex); | |
1a17662e | 471 | goto err; |
b5230b56 | 472 | } |
f48fc4d3 | 473 | } |
b5230b56 | 474 | mutex_unlock(&blk_tree_mutex); |
f48fc4d3 JA |
475 | |
476 | dir = debugfs_create_dir(buts->name, blk_tree_root); | |
477 | ||
2056a782 JA |
478 | if (!dir) |
479 | goto err; | |
480 | ||
481 | bt->dir = dir; | |
6da127ad | 482 | bt->dev = dev; |
2056a782 JA |
483 | atomic_set(&bt->dropped, 0); |
484 | ||
485 | ret = -EIO; | |
939b3669 ACM |
486 | bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt, |
487 | &blk_dropped_fops); | |
2056a782 JA |
488 | if (!bt->dropped_file) |
489 | goto err; | |
490 | ||
02c62304 AB |
491 | bt->msg_file = debugfs_create_file("msg", 0222, dir, bt, &blk_msg_fops); |
492 | if (!bt->msg_file) | |
493 | goto err; | |
494 | ||
171044d4 AB |
495 | bt->rchan = relay_open("trace", dir, buts->buf_size, |
496 | buts->buf_nr, &blk_relay_callbacks, bt); | |
2056a782 JA |
497 | if (!bt->rchan) |
498 | goto err; | |
2056a782 | 499 | |
171044d4 | 500 | bt->act_mask = buts->act_mask; |
2056a782 JA |
501 | if (!bt->act_mask) |
502 | bt->act_mask = (u16) -1; | |
503 | ||
9908c309 | 504 | blk_trace_setup_lba(bt, bdev); |
2056a782 | 505 | |
d0deef5b SD |
506 | /* overwrite with user settings */ |
507 | if (buts->start_lba) | |
508 | bt->start_lba = buts->start_lba; | |
509 | if (buts->end_lba) | |
510 | bt->end_lba = buts->end_lba; | |
511 | ||
171044d4 | 512 | bt->pid = buts->pid; |
2056a782 JA |
513 | bt->trace_state = Blktrace_setup; |
514 | ||
515 | ret = -EBUSY; | |
516 | old_bt = xchg(&q->blk_trace, bt); | |
517 | if (old_bt) { | |
518 | (void) xchg(&q->blk_trace, old_bt); | |
519 | goto err; | |
520 | } | |
521 | ||
17ba97e3 | 522 | if (atomic_inc_return(&blk_probes_ref) == 1) |
cbe28296 LZ |
523 | blk_register_tracepoints(); |
524 | ||
2056a782 JA |
525 | return 0; |
526 | err: | |
ad5dd549 | 527 | blk_trace_free(bt); |
2056a782 JA |
528 | return ret; |
529 | } | |
171044d4 | 530 | |
6da127ad | 531 | int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, |
d0deef5b | 532 | struct block_device *bdev, |
6da127ad | 533 | char __user *arg) |
171044d4 AB |
534 | { |
535 | struct blk_user_trace_setup buts; | |
536 | int ret; | |
537 | ||
538 | ret = copy_from_user(&buts, arg, sizeof(buts)); | |
539 | if (ret) | |
540 | return -EFAULT; | |
541 | ||
d0deef5b | 542 | ret = do_blk_trace_setup(q, name, dev, bdev, &buts); |
171044d4 AB |
543 | if (ret) |
544 | return ret; | |
545 | ||
9a8c28c8 DM |
546 | if (copy_to_user(arg, &buts, sizeof(buts))) { |
547 | blk_trace_remove(q); | |
171044d4 | 548 | return -EFAULT; |
9a8c28c8 | 549 | } |
171044d4 AB |
550 | return 0; |
551 | } | |
6da127ad | 552 | EXPORT_SYMBOL_GPL(blk_trace_setup); |
2056a782 | 553 | |
62c2a7d9 AB |
554 | #if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64) |
555 | static int compat_blk_trace_setup(struct request_queue *q, char *name, | |
556 | dev_t dev, struct block_device *bdev, | |
557 | char __user *arg) | |
558 | { | |
559 | struct blk_user_trace_setup buts; | |
560 | struct compat_blk_user_trace_setup cbuts; | |
561 | int ret; | |
562 | ||
563 | if (copy_from_user(&cbuts, arg, sizeof(cbuts))) | |
564 | return -EFAULT; | |
565 | ||
566 | buts = (struct blk_user_trace_setup) { | |
567 | .act_mask = cbuts.act_mask, | |
568 | .buf_size = cbuts.buf_size, | |
569 | .buf_nr = cbuts.buf_nr, | |
570 | .start_lba = cbuts.start_lba, | |
571 | .end_lba = cbuts.end_lba, | |
572 | .pid = cbuts.pid, | |
573 | }; | |
574 | memcpy(&buts.name, &cbuts.name, 32); | |
575 | ||
576 | ret = do_blk_trace_setup(q, name, dev, bdev, &buts); | |
577 | if (ret) | |
578 | return ret; | |
579 | ||
580 | if (copy_to_user(arg, &buts.name, 32)) { | |
581 | blk_trace_remove(q); | |
582 | return -EFAULT; | |
583 | } | |
584 | ||
585 | return 0; | |
586 | } | |
587 | #endif | |
588 | ||
6da127ad | 589 | int blk_trace_startstop(struct request_queue *q, int start) |
2056a782 | 590 | { |
2056a782 | 591 | int ret; |
939b3669 | 592 | struct blk_trace *bt = q->blk_trace; |
2056a782 | 593 | |
939b3669 | 594 | if (bt == NULL) |
2056a782 JA |
595 | return -EINVAL; |
596 | ||
597 | /* | |
598 | * For starting a trace, we can transition from a setup or stopped | |
599 | * trace. For stopping a trace, the state must be running | |
600 | */ | |
601 | ret = -EINVAL; | |
602 | if (start) { | |
603 | if (bt->trace_state == Blktrace_setup || | |
604 | bt->trace_state == Blktrace_stopped) { | |
605 | blktrace_seq++; | |
606 | smp_mb(); | |
607 | bt->trace_state = Blktrace_running; | |
be1c6341 OK |
608 | |
609 | trace_note_time(bt); | |
2056a782 JA |
610 | ret = 0; |
611 | } | |
612 | } else { | |
613 | if (bt->trace_state == Blktrace_running) { | |
614 | bt->trace_state = Blktrace_stopped; | |
615 | relay_flush(bt->rchan); | |
616 | ret = 0; | |
617 | } | |
618 | } | |
619 | ||
620 | return ret; | |
621 | } | |
6da127ad | 622 | EXPORT_SYMBOL_GPL(blk_trace_startstop); |
2056a782 JA |
623 | |
624 | /** | |
625 | * blk_trace_ioctl: - handle the ioctls associated with tracing | |
626 | * @bdev: the block device | |
ef18012b | 627 | * @cmd: the ioctl cmd |
2056a782 JA |
628 | * @arg: the argument data, if any |
629 | * | |
630 | **/ | |
631 | int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) | |
632 | { | |
165125e1 | 633 | struct request_queue *q; |
2056a782 | 634 | int ret, start = 0; |
6da127ad | 635 | char b[BDEVNAME_SIZE]; |
2056a782 JA |
636 | |
637 | q = bdev_get_queue(bdev); | |
638 | if (!q) | |
639 | return -ENXIO; | |
640 | ||
641 | mutex_lock(&bdev->bd_mutex); | |
642 | ||
643 | switch (cmd) { | |
644 | case BLKTRACESETUP: | |
f36f21ec | 645 | bdevname(bdev, b); |
d0deef5b | 646 | ret = blk_trace_setup(q, b, bdev->bd_dev, bdev, arg); |
2056a782 | 647 | break; |
62c2a7d9 AB |
648 | #if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64) |
649 | case BLKTRACESETUP32: | |
650 | bdevname(bdev, b); | |
651 | ret = compat_blk_trace_setup(q, b, bdev->bd_dev, bdev, arg); | |
652 | break; | |
653 | #endif | |
2056a782 JA |
654 | case BLKTRACESTART: |
655 | start = 1; | |
656 | case BLKTRACESTOP: | |
657 | ret = blk_trace_startstop(q, start); | |
658 | break; | |
659 | case BLKTRACETEARDOWN: | |
660 | ret = blk_trace_remove(q); | |
661 | break; | |
662 | default: | |
663 | ret = -ENOTTY; | |
664 | break; | |
665 | } | |
666 | ||
667 | mutex_unlock(&bdev->bd_mutex); | |
668 | return ret; | |
669 | } | |
670 | ||
671 | /** | |
672 | * blk_trace_shutdown: - stop and cleanup trace structures | |
673 | * @q: the request queue associated with the device | |
674 | * | |
675 | **/ | |
165125e1 | 676 | void blk_trace_shutdown(struct request_queue *q) |
2056a782 | 677 | { |
6c5c9341 AD |
678 | if (q->blk_trace) { |
679 | blk_trace_startstop(q, 0); | |
680 | blk_trace_remove(q); | |
681 | } | |
2056a782 | 682 | } |
5f3ea37c ACM |
683 | |
684 | /* | |
685 | * blktrace probes | |
686 | */ | |
687 | ||
688 | /** | |
689 | * blk_add_trace_rq - Add a trace for a request oriented action | |
690 | * @q: queue the io is for | |
691 | * @rq: the source request | |
692 | * @what: the action | |
693 | * | |
694 | * Description: | |
695 | * Records an action against a request. Will log the bio offset + size. | |
696 | * | |
697 | **/ | |
698 | static void blk_add_trace_rq(struct request_queue *q, struct request *rq, | |
699 | u32 what) | |
700 | { | |
701 | struct blk_trace *bt = q->blk_trace; | |
702 | int rw = rq->cmd_flags & 0x03; | |
703 | ||
704 | if (likely(!bt)) | |
705 | return; | |
706 | ||
33659ebb | 707 | if (rq->cmd_flags & REQ_DISCARD) |
7b6d91da | 708 | rw |= REQ_DISCARD; |
5f3ea37c | 709 | |
8d57a98c AH |
710 | if (rq->cmd_flags & REQ_SECURE) |
711 | rw |= REQ_SECURE; | |
712 | ||
33659ebb | 713 | if (rq->cmd_type == REQ_TYPE_BLOCK_PC) { |
5f3ea37c | 714 | what |= BLK_TC_ACT(BLK_TC_PC); |
2e46e8b2 TH |
715 | __blk_add_trace(bt, 0, blk_rq_bytes(rq), rw, |
716 | what, rq->errors, rq->cmd_len, rq->cmd); | |
5f3ea37c ACM |
717 | } else { |
718 | what |= BLK_TC_ACT(BLK_TC_FS); | |
2e46e8b2 TH |
719 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), rw, |
720 | what, rq->errors, 0, NULL); | |
5f3ea37c ACM |
721 | } |
722 | } | |
723 | ||
38516ab5 SR |
724 | static void blk_add_trace_rq_abort(void *ignore, |
725 | struct request_queue *q, struct request *rq) | |
5f3ea37c ACM |
726 | { |
727 | blk_add_trace_rq(q, rq, BLK_TA_ABORT); | |
728 | } | |
729 | ||
38516ab5 SR |
730 | static void blk_add_trace_rq_insert(void *ignore, |
731 | struct request_queue *q, struct request *rq) | |
5f3ea37c ACM |
732 | { |
733 | blk_add_trace_rq(q, rq, BLK_TA_INSERT); | |
734 | } | |
735 | ||
38516ab5 SR |
736 | static void blk_add_trace_rq_issue(void *ignore, |
737 | struct request_queue *q, struct request *rq) | |
5f3ea37c ACM |
738 | { |
739 | blk_add_trace_rq(q, rq, BLK_TA_ISSUE); | |
740 | } | |
741 | ||
38516ab5 SR |
742 | static void blk_add_trace_rq_requeue(void *ignore, |
743 | struct request_queue *q, | |
939b3669 | 744 | struct request *rq) |
5f3ea37c ACM |
745 | { |
746 | blk_add_trace_rq(q, rq, BLK_TA_REQUEUE); | |
747 | } | |
748 | ||
38516ab5 SR |
749 | static void blk_add_trace_rq_complete(void *ignore, |
750 | struct request_queue *q, | |
939b3669 | 751 | struct request *rq) |
5f3ea37c ACM |
752 | { |
753 | blk_add_trace_rq(q, rq, BLK_TA_COMPLETE); | |
754 | } | |
755 | ||
756 | /** | |
757 | * blk_add_trace_bio - Add a trace for a bio oriented action | |
758 | * @q: queue the io is for | |
759 | * @bio: the source bio | |
760 | * @what: the action | |
761 | * | |
762 | * Description: | |
763 | * Records an action against a bio. Will log the bio offset + size. | |
764 | * | |
765 | **/ | |
766 | static void blk_add_trace_bio(struct request_queue *q, struct bio *bio, | |
767 | u32 what) | |
768 | { | |
769 | struct blk_trace *bt = q->blk_trace; | |
770 | ||
771 | if (likely(!bt)) | |
772 | return; | |
773 | ||
774 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, | |
775 | !bio_flagged(bio, BIO_UPTODATE), 0, NULL); | |
776 | } | |
777 | ||
38516ab5 SR |
778 | static void blk_add_trace_bio_bounce(void *ignore, |
779 | struct request_queue *q, struct bio *bio) | |
5f3ea37c ACM |
780 | { |
781 | blk_add_trace_bio(q, bio, BLK_TA_BOUNCE); | |
782 | } | |
783 | ||
38516ab5 SR |
784 | static void blk_add_trace_bio_complete(void *ignore, |
785 | struct request_queue *q, struct bio *bio) | |
5f3ea37c ACM |
786 | { |
787 | blk_add_trace_bio(q, bio, BLK_TA_COMPLETE); | |
788 | } | |
789 | ||
38516ab5 SR |
790 | static void blk_add_trace_bio_backmerge(void *ignore, |
791 | struct request_queue *q, | |
939b3669 | 792 | struct bio *bio) |
5f3ea37c ACM |
793 | { |
794 | blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE); | |
795 | } | |
796 | ||
38516ab5 SR |
797 | static void blk_add_trace_bio_frontmerge(void *ignore, |
798 | struct request_queue *q, | |
939b3669 | 799 | struct bio *bio) |
5f3ea37c ACM |
800 | { |
801 | blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE); | |
802 | } | |
803 | ||
38516ab5 SR |
804 | static void blk_add_trace_bio_queue(void *ignore, |
805 | struct request_queue *q, struct bio *bio) | |
5f3ea37c ACM |
806 | { |
807 | blk_add_trace_bio(q, bio, BLK_TA_QUEUE); | |
808 | } | |
809 | ||
38516ab5 SR |
810 | static void blk_add_trace_getrq(void *ignore, |
811 | struct request_queue *q, | |
939b3669 | 812 | struct bio *bio, int rw) |
5f3ea37c ACM |
813 | { |
814 | if (bio) | |
815 | blk_add_trace_bio(q, bio, BLK_TA_GETRQ); | |
816 | else { | |
817 | struct blk_trace *bt = q->blk_trace; | |
818 | ||
819 | if (bt) | |
820 | __blk_add_trace(bt, 0, 0, rw, BLK_TA_GETRQ, 0, 0, NULL); | |
821 | } | |
822 | } | |
823 | ||
824 | ||
38516ab5 SR |
825 | static void blk_add_trace_sleeprq(void *ignore, |
826 | struct request_queue *q, | |
939b3669 | 827 | struct bio *bio, int rw) |
5f3ea37c ACM |
828 | { |
829 | if (bio) | |
830 | blk_add_trace_bio(q, bio, BLK_TA_SLEEPRQ); | |
831 | else { | |
832 | struct blk_trace *bt = q->blk_trace; | |
833 | ||
834 | if (bt) | |
939b3669 ACM |
835 | __blk_add_trace(bt, 0, 0, rw, BLK_TA_SLEEPRQ, |
836 | 0, 0, NULL); | |
5f3ea37c ACM |
837 | } |
838 | } | |
839 | ||
38516ab5 | 840 | static void blk_add_trace_plug(void *ignore, struct request_queue *q) |
5f3ea37c ACM |
841 | { |
842 | struct blk_trace *bt = q->blk_trace; | |
843 | ||
844 | if (bt) | |
845 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_PLUG, 0, 0, NULL); | |
846 | } | |
847 | ||
38516ab5 | 848 | static void blk_add_trace_unplug_io(void *ignore, struct request_queue *q) |
5f3ea37c ACM |
849 | { |
850 | struct blk_trace *bt = q->blk_trace; | |
851 | ||
852 | if (bt) { | |
853 | unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; | |
854 | __be64 rpdu = cpu_to_be64(pdu); | |
855 | ||
856 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_IO, 0, | |
857 | sizeof(rpdu), &rpdu); | |
858 | } | |
859 | } | |
860 | ||
38516ab5 | 861 | static void blk_add_trace_unplug_timer(void *ignore, struct request_queue *q) |
5f3ea37c ACM |
862 | { |
863 | struct blk_trace *bt = q->blk_trace; | |
864 | ||
865 | if (bt) { | |
866 | unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; | |
867 | __be64 rpdu = cpu_to_be64(pdu); | |
868 | ||
869 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_TIMER, 0, | |
870 | sizeof(rpdu), &rpdu); | |
871 | } | |
872 | } | |
873 | ||
38516ab5 SR |
874 | static void blk_add_trace_split(void *ignore, |
875 | struct request_queue *q, struct bio *bio, | |
5f3ea37c ACM |
876 | unsigned int pdu) |
877 | { | |
878 | struct blk_trace *bt = q->blk_trace; | |
879 | ||
880 | if (bt) { | |
881 | __be64 rpdu = cpu_to_be64(pdu); | |
882 | ||
883 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, | |
884 | BLK_TA_SPLIT, !bio_flagged(bio, BIO_UPTODATE), | |
885 | sizeof(rpdu), &rpdu); | |
886 | } | |
887 | } | |
888 | ||
889 | /** | |
890 | * blk_add_trace_remap - Add a trace for a remap operation | |
546cf44a | 891 | * @ignore: trace callback data parameter (not used) |
5f3ea37c ACM |
892 | * @q: queue the io is for |
893 | * @bio: the source bio | |
894 | * @dev: target device | |
a42aaa3b | 895 | * @from: source sector |
5f3ea37c ACM |
896 | * |
897 | * Description: | |
898 | * Device mapper or raid target sometimes need to split a bio because | |
899 | * it spans a stripe (or similar). Add a trace for that action. | |
900 | * | |
901 | **/ | |
38516ab5 SR |
902 | static void blk_add_trace_remap(void *ignore, |
903 | struct request_queue *q, struct bio *bio, | |
904 | dev_t dev, sector_t from) | |
5f3ea37c ACM |
905 | { |
906 | struct blk_trace *bt = q->blk_trace; | |
907 | struct blk_io_trace_remap r; | |
908 | ||
909 | if (likely(!bt)) | |
910 | return; | |
911 | ||
a42aaa3b AB |
912 | r.device_from = cpu_to_be32(dev); |
913 | r.device_to = cpu_to_be32(bio->bi_bdev->bd_dev); | |
914 | r.sector_from = cpu_to_be64(from); | |
5f3ea37c | 915 | |
22a7c31a AB |
916 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, |
917 | BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), | |
918 | sizeof(r), &r); | |
5f3ea37c ACM |
919 | } |
920 | ||
b0da3f0d JN |
921 | /** |
922 | * blk_add_trace_rq_remap - Add a trace for a request-remap operation | |
546cf44a | 923 | * @ignore: trace callback data parameter (not used) |
b0da3f0d JN |
924 | * @q: queue the io is for |
925 | * @rq: the source request | |
926 | * @dev: target device | |
927 | * @from: source sector | |
928 | * | |
929 | * Description: | |
930 | * Device mapper remaps request to other devices. | |
931 | * Add a trace for that action. | |
932 | * | |
933 | **/ | |
38516ab5 SR |
934 | static void blk_add_trace_rq_remap(void *ignore, |
935 | struct request_queue *q, | |
b0da3f0d JN |
936 | struct request *rq, dev_t dev, |
937 | sector_t from) | |
938 | { | |
939 | struct blk_trace *bt = q->blk_trace; | |
940 | struct blk_io_trace_remap r; | |
941 | ||
942 | if (likely(!bt)) | |
943 | return; | |
944 | ||
945 | r.device_from = cpu_to_be32(dev); | |
946 | r.device_to = cpu_to_be32(disk_devt(rq->rq_disk)); | |
947 | r.sector_from = cpu_to_be64(from); | |
948 | ||
949 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), | |
950 | rq_data_dir(rq), BLK_TA_REMAP, !!rq->errors, | |
951 | sizeof(r), &r); | |
952 | } | |
953 | ||
5f3ea37c ACM |
954 | /** |
955 | * blk_add_driver_data - Add binary message with driver-specific data | |
956 | * @q: queue the io is for | |
957 | * @rq: io request | |
958 | * @data: driver-specific data | |
959 | * @len: length of driver-specific data | |
960 | * | |
961 | * Description: | |
962 | * Some drivers might want to write driver-specific data per request. | |
963 | * | |
964 | **/ | |
965 | void blk_add_driver_data(struct request_queue *q, | |
966 | struct request *rq, | |
967 | void *data, size_t len) | |
968 | { | |
969 | struct blk_trace *bt = q->blk_trace; | |
970 | ||
971 | if (likely(!bt)) | |
972 | return; | |
973 | ||
33659ebb | 974 | if (rq->cmd_type == REQ_TYPE_BLOCK_PC) |
2e46e8b2 TH |
975 | __blk_add_trace(bt, 0, blk_rq_bytes(rq), 0, |
976 | BLK_TA_DRV_DATA, rq->errors, len, data); | |
5f3ea37c | 977 | else |
2e46e8b2 TH |
978 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), 0, |
979 | BLK_TA_DRV_DATA, rq->errors, len, data); | |
5f3ea37c ACM |
980 | } |
981 | EXPORT_SYMBOL_GPL(blk_add_driver_data); | |
982 | ||
3c289ba7 | 983 | static void blk_register_tracepoints(void) |
5f3ea37c ACM |
984 | { |
985 | int ret; | |
986 | ||
38516ab5 | 987 | ret = register_trace_block_rq_abort(blk_add_trace_rq_abort, NULL); |
5f3ea37c | 988 | WARN_ON(ret); |
38516ab5 | 989 | ret = register_trace_block_rq_insert(blk_add_trace_rq_insert, NULL); |
5f3ea37c | 990 | WARN_ON(ret); |
38516ab5 | 991 | ret = register_trace_block_rq_issue(blk_add_trace_rq_issue, NULL); |
5f3ea37c | 992 | WARN_ON(ret); |
38516ab5 | 993 | ret = register_trace_block_rq_requeue(blk_add_trace_rq_requeue, NULL); |
5f3ea37c | 994 | WARN_ON(ret); |
38516ab5 | 995 | ret = register_trace_block_rq_complete(blk_add_trace_rq_complete, NULL); |
5f3ea37c | 996 | WARN_ON(ret); |
38516ab5 | 997 | ret = register_trace_block_bio_bounce(blk_add_trace_bio_bounce, NULL); |
5f3ea37c | 998 | WARN_ON(ret); |
38516ab5 | 999 | ret = register_trace_block_bio_complete(blk_add_trace_bio_complete, NULL); |
5f3ea37c | 1000 | WARN_ON(ret); |
38516ab5 | 1001 | ret = register_trace_block_bio_backmerge(blk_add_trace_bio_backmerge, NULL); |
5f3ea37c | 1002 | WARN_ON(ret); |
38516ab5 | 1003 | ret = register_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge, NULL); |
5f3ea37c | 1004 | WARN_ON(ret); |
38516ab5 | 1005 | ret = register_trace_block_bio_queue(blk_add_trace_bio_queue, NULL); |
5f3ea37c | 1006 | WARN_ON(ret); |
38516ab5 | 1007 | ret = register_trace_block_getrq(blk_add_trace_getrq, NULL); |
5f3ea37c | 1008 | WARN_ON(ret); |
38516ab5 | 1009 | ret = register_trace_block_sleeprq(blk_add_trace_sleeprq, NULL); |
5f3ea37c | 1010 | WARN_ON(ret); |
38516ab5 | 1011 | ret = register_trace_block_plug(blk_add_trace_plug, NULL); |
5f3ea37c | 1012 | WARN_ON(ret); |
38516ab5 | 1013 | ret = register_trace_block_unplug_timer(blk_add_trace_unplug_timer, NULL); |
5f3ea37c | 1014 | WARN_ON(ret); |
38516ab5 | 1015 | ret = register_trace_block_unplug_io(blk_add_trace_unplug_io, NULL); |
5f3ea37c | 1016 | WARN_ON(ret); |
38516ab5 | 1017 | ret = register_trace_block_split(blk_add_trace_split, NULL); |
5f3ea37c | 1018 | WARN_ON(ret); |
38516ab5 | 1019 | ret = register_trace_block_remap(blk_add_trace_remap, NULL); |
5f3ea37c | 1020 | WARN_ON(ret); |
38516ab5 | 1021 | ret = register_trace_block_rq_remap(blk_add_trace_rq_remap, NULL); |
b0da3f0d | 1022 | WARN_ON(ret); |
5f3ea37c ACM |
1023 | } |
1024 | ||
1025 | static void blk_unregister_tracepoints(void) | |
1026 | { | |
38516ab5 SR |
1027 | unregister_trace_block_rq_remap(blk_add_trace_rq_remap, NULL); |
1028 | unregister_trace_block_remap(blk_add_trace_remap, NULL); | |
1029 | unregister_trace_block_split(blk_add_trace_split, NULL); | |
1030 | unregister_trace_block_unplug_io(blk_add_trace_unplug_io, NULL); | |
1031 | unregister_trace_block_unplug_timer(blk_add_trace_unplug_timer, NULL); | |
1032 | unregister_trace_block_plug(blk_add_trace_plug, NULL); | |
1033 | unregister_trace_block_sleeprq(blk_add_trace_sleeprq, NULL); | |
1034 | unregister_trace_block_getrq(blk_add_trace_getrq, NULL); | |
1035 | unregister_trace_block_bio_queue(blk_add_trace_bio_queue, NULL); | |
1036 | unregister_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge, NULL); | |
1037 | unregister_trace_block_bio_backmerge(blk_add_trace_bio_backmerge, NULL); | |
1038 | unregister_trace_block_bio_complete(blk_add_trace_bio_complete, NULL); | |
1039 | unregister_trace_block_bio_bounce(blk_add_trace_bio_bounce, NULL); | |
1040 | unregister_trace_block_rq_complete(blk_add_trace_rq_complete, NULL); | |
1041 | unregister_trace_block_rq_requeue(blk_add_trace_rq_requeue, NULL); | |
1042 | unregister_trace_block_rq_issue(blk_add_trace_rq_issue, NULL); | |
1043 | unregister_trace_block_rq_insert(blk_add_trace_rq_insert, NULL); | |
1044 | unregister_trace_block_rq_abort(blk_add_trace_rq_abort, NULL); | |
5f3ea37c ACM |
1045 | |
1046 | tracepoint_synchronize_unregister(); | |
1047 | } | |
c71a8961 ACM |
1048 | |
1049 | /* | |
1050 | * struct blk_io_tracer formatting routines | |
1051 | */ | |
1052 | ||
1053 | static void fill_rwbs(char *rwbs, const struct blk_io_trace *t) | |
1054 | { | |
157f9c00 | 1055 | int i = 0; |
65796348 | 1056 | int tc = t->action >> BLK_TC_SHIFT; |
157f9c00 | 1057 | |
18cea459 LZ |
1058 | if (t->action == BLK_TN_MESSAGE) { |
1059 | rwbs[i++] = 'N'; | |
1060 | goto out; | |
1061 | } | |
1062 | ||
65796348 | 1063 | if (tc & BLK_TC_DISCARD) |
157f9c00 | 1064 | rwbs[i++] = 'D'; |
65796348 | 1065 | else if (tc & BLK_TC_WRITE) |
157f9c00 ACM |
1066 | rwbs[i++] = 'W'; |
1067 | else if (t->bytes) | |
1068 | rwbs[i++] = 'R'; | |
1069 | else | |
1070 | rwbs[i++] = 'N'; | |
1071 | ||
65796348 | 1072 | if (tc & BLK_TC_AHEAD) |
157f9c00 | 1073 | rwbs[i++] = 'A'; |
65796348 | 1074 | if (tc & BLK_TC_BARRIER) |
157f9c00 | 1075 | rwbs[i++] = 'B'; |
65796348 | 1076 | if (tc & BLK_TC_SYNC) |
157f9c00 | 1077 | rwbs[i++] = 'S'; |
65796348 | 1078 | if (tc & BLK_TC_META) |
157f9c00 | 1079 | rwbs[i++] = 'M'; |
18cea459 | 1080 | out: |
157f9c00 | 1081 | rwbs[i] = '\0'; |
c71a8961 ACM |
1082 | } |
1083 | ||
1084 | static inline | |
1085 | const struct blk_io_trace *te_blk_io_trace(const struct trace_entry *ent) | |
1086 | { | |
1087 | return (const struct blk_io_trace *)ent; | |
1088 | } | |
1089 | ||
1090 | static inline const void *pdu_start(const struct trace_entry *ent) | |
1091 | { | |
1092 | return te_blk_io_trace(ent) + 1; | |
1093 | } | |
1094 | ||
66de7792 LZ |
1095 | static inline u32 t_action(const struct trace_entry *ent) |
1096 | { | |
1097 | return te_blk_io_trace(ent)->action; | |
1098 | } | |
1099 | ||
1100 | static inline u32 t_bytes(const struct trace_entry *ent) | |
1101 | { | |
1102 | return te_blk_io_trace(ent)->bytes; | |
1103 | } | |
1104 | ||
c71a8961 ACM |
1105 | static inline u32 t_sec(const struct trace_entry *ent) |
1106 | { | |
1107 | return te_blk_io_trace(ent)->bytes >> 9; | |
1108 | } | |
1109 | ||
1110 | static inline unsigned long long t_sector(const struct trace_entry *ent) | |
1111 | { | |
1112 | return te_blk_io_trace(ent)->sector; | |
1113 | } | |
1114 | ||
1115 | static inline __u16 t_error(const struct trace_entry *ent) | |
1116 | { | |
e0dc81be | 1117 | return te_blk_io_trace(ent)->error; |
c71a8961 ACM |
1118 | } |
1119 | ||
1120 | static __u64 get_pdu_int(const struct trace_entry *ent) | |
1121 | { | |
1122 | const __u64 *val = pdu_start(ent); | |
1123 | return be64_to_cpu(*val); | |
1124 | } | |
1125 | ||
1126 | static void get_pdu_remap(const struct trace_entry *ent, | |
1127 | struct blk_io_trace_remap *r) | |
1128 | { | |
1129 | const struct blk_io_trace_remap *__r = pdu_start(ent); | |
a42aaa3b | 1130 | __u64 sector_from = __r->sector_from; |
c71a8961 | 1131 | |
c71a8961 | 1132 | r->device_from = be32_to_cpu(__r->device_from); |
a42aaa3b AB |
1133 | r->device_to = be32_to_cpu(__r->device_to); |
1134 | r->sector_from = be64_to_cpu(sector_from); | |
c71a8961 ACM |
1135 | } |
1136 | ||
b6a4b0c3 LZ |
1137 | typedef int (blk_log_action_t) (struct trace_iterator *iter, const char *act); |
1138 | ||
1139 | static int blk_log_action_classic(struct trace_iterator *iter, const char *act) | |
c71a8961 ACM |
1140 | { |
1141 | char rwbs[6]; | |
35ac51bf LZ |
1142 | unsigned long long ts = iter->ts; |
1143 | unsigned long nsec_rem = do_div(ts, NSEC_PER_SEC); | |
c71a8961 | 1144 | unsigned secs = (unsigned long)ts; |
b6a4b0c3 | 1145 | const struct blk_io_trace *t = te_blk_io_trace(iter->ent); |
c71a8961 ACM |
1146 | |
1147 | fill_rwbs(rwbs, t); | |
1148 | ||
1149 | return trace_seq_printf(&iter->seq, | |
35ac51bf | 1150 | "%3d,%-3d %2d %5d.%09lu %5u %2s %3s ", |
c71a8961 | 1151 | MAJOR(t->device), MINOR(t->device), iter->cpu, |
b6a4b0c3 | 1152 | secs, nsec_rem, iter->ent->pid, act, rwbs); |
c71a8961 ACM |
1153 | } |
1154 | ||
b6a4b0c3 | 1155 | static int blk_log_action(struct trace_iterator *iter, const char *act) |
c71a8961 ACM |
1156 | { |
1157 | char rwbs[6]; | |
b6a4b0c3 LZ |
1158 | const struct blk_io_trace *t = te_blk_io_trace(iter->ent); |
1159 | ||
c71a8961 | 1160 | fill_rwbs(rwbs, t); |
b6a4b0c3 | 1161 | return trace_seq_printf(&iter->seq, "%3d,%-3d %2s %3s ", |
c71a8961 ACM |
1162 | MAJOR(t->device), MINOR(t->device), act, rwbs); |
1163 | } | |
1164 | ||
66de7792 LZ |
1165 | static int blk_log_dump_pdu(struct trace_seq *s, const struct trace_entry *ent) |
1166 | { | |
04986257 | 1167 | const unsigned char *pdu_buf; |
66de7792 LZ |
1168 | int pdu_len; |
1169 | int i, end, ret; | |
1170 | ||
1171 | pdu_buf = pdu_start(ent); | |
1172 | pdu_len = te_blk_io_trace(ent)->pdu_len; | |
1173 | ||
1174 | if (!pdu_len) | |
1175 | return 1; | |
1176 | ||
1177 | /* find the last zero that needs to be printed */ | |
1178 | for (end = pdu_len - 1; end >= 0; end--) | |
1179 | if (pdu_buf[end]) | |
1180 | break; | |
1181 | end++; | |
1182 | ||
1183 | if (!trace_seq_putc(s, '(')) | |
1184 | return 0; | |
1185 | ||
1186 | for (i = 0; i < pdu_len; i++) { | |
1187 | ||
1188 | ret = trace_seq_printf(s, "%s%02x", | |
1189 | i == 0 ? "" : " ", pdu_buf[i]); | |
1190 | if (!ret) | |
1191 | return ret; | |
1192 | ||
1193 | /* | |
1194 | * stop when the rest is just zeroes and indicate so | |
1195 | * with a ".." appended | |
1196 | */ | |
1197 | if (i == end && end != pdu_len - 1) | |
1198 | return trace_seq_puts(s, " ..) "); | |
1199 | } | |
1200 | ||
1201 | return trace_seq_puts(s, ") "); | |
1202 | } | |
1203 | ||
c71a8961 ACM |
1204 | static int blk_log_generic(struct trace_seq *s, const struct trace_entry *ent) |
1205 | { | |
4ca53085 SR |
1206 | char cmd[TASK_COMM_LEN]; |
1207 | ||
1208 | trace_find_cmdline(ent->pid, cmd); | |
c71a8961 | 1209 | |
66de7792 LZ |
1210 | if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { |
1211 | int ret; | |
1212 | ||
1213 | ret = trace_seq_printf(s, "%u ", t_bytes(ent)); | |
1214 | if (!ret) | |
1215 | return 0; | |
1216 | ret = blk_log_dump_pdu(s, ent); | |
1217 | if (!ret) | |
1218 | return 0; | |
1219 | return trace_seq_printf(s, "[%s]\n", cmd); | |
1220 | } else { | |
1221 | if (t_sec(ent)) | |
1222 | return trace_seq_printf(s, "%llu + %u [%s]\n", | |
1223 | t_sector(ent), t_sec(ent), cmd); | |
1224 | return trace_seq_printf(s, "[%s]\n", cmd); | |
1225 | } | |
c71a8961 ACM |
1226 | } |
1227 | ||
157f9c00 ACM |
1228 | static int blk_log_with_error(struct trace_seq *s, |
1229 | const struct trace_entry *ent) | |
c71a8961 | 1230 | { |
66de7792 LZ |
1231 | if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { |
1232 | int ret; | |
1233 | ||
1234 | ret = blk_log_dump_pdu(s, ent); | |
1235 | if (ret) | |
1236 | return trace_seq_printf(s, "[%d]\n", t_error(ent)); | |
1237 | return 0; | |
1238 | } else { | |
1239 | if (t_sec(ent)) | |
1240 | return trace_seq_printf(s, "%llu + %u [%d]\n", | |
1241 | t_sector(ent), | |
1242 | t_sec(ent), t_error(ent)); | |
1243 | return trace_seq_printf(s, "%llu [%d]\n", | |
1244 | t_sector(ent), t_error(ent)); | |
1245 | } | |
c71a8961 ACM |
1246 | } |
1247 | ||
1248 | static int blk_log_remap(struct trace_seq *s, const struct trace_entry *ent) | |
1249 | { | |
a42aaa3b | 1250 | struct blk_io_trace_remap r = { .device_from = 0, }; |
c71a8961 ACM |
1251 | |
1252 | get_pdu_remap(ent, &r); | |
1253 | return trace_seq_printf(s, "%llu + %u <- (%d,%d) %llu\n", | |
a42aaa3b AB |
1254 | t_sector(ent), t_sec(ent), |
1255 | MAJOR(r.device_from), MINOR(r.device_from), | |
1256 | (unsigned long long)r.sector_from); | |
c71a8961 ACM |
1257 | } |
1258 | ||
1259 | static int blk_log_plug(struct trace_seq *s, const struct trace_entry *ent) | |
1260 | { | |
4ca53085 SR |
1261 | char cmd[TASK_COMM_LEN]; |
1262 | ||
1263 | trace_find_cmdline(ent->pid, cmd); | |
1264 | ||
1265 | return trace_seq_printf(s, "[%s]\n", cmd); | |
c71a8961 ACM |
1266 | } |
1267 | ||
1268 | static int blk_log_unplug(struct trace_seq *s, const struct trace_entry *ent) | |
1269 | { | |
4ca53085 SR |
1270 | char cmd[TASK_COMM_LEN]; |
1271 | ||
1272 | trace_find_cmdline(ent->pid, cmd); | |
1273 | ||
1274 | return trace_seq_printf(s, "[%s] %llu\n", cmd, get_pdu_int(ent)); | |
c71a8961 ACM |
1275 | } |
1276 | ||
1277 | static int blk_log_split(struct trace_seq *s, const struct trace_entry *ent) | |
1278 | { | |
4ca53085 SR |
1279 | char cmd[TASK_COMM_LEN]; |
1280 | ||
1281 | trace_find_cmdline(ent->pid, cmd); | |
1282 | ||
c71a8961 | 1283 | return trace_seq_printf(s, "%llu / %llu [%s]\n", t_sector(ent), |
4ca53085 | 1284 | get_pdu_int(ent), cmd); |
c71a8961 ACM |
1285 | } |
1286 | ||
18cea459 LZ |
1287 | static int blk_log_msg(struct trace_seq *s, const struct trace_entry *ent) |
1288 | { | |
1289 | int ret; | |
1290 | const struct blk_io_trace *t = te_blk_io_trace(ent); | |
1291 | ||
1292 | ret = trace_seq_putmem(s, t + 1, t->pdu_len); | |
1293 | if (ret) | |
1294 | return trace_seq_putc(s, '\n'); | |
1295 | return ret; | |
1296 | } | |
1297 | ||
c71a8961 ACM |
1298 | /* |
1299 | * struct tracer operations | |
1300 | */ | |
1301 | ||
1302 | static void blk_tracer_print_header(struct seq_file *m) | |
1303 | { | |
1304 | if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) | |
1305 | return; | |
1306 | seq_puts(m, "# DEV CPU TIMESTAMP PID ACT FLG\n" | |
1307 | "# | | | | | |\n"); | |
1308 | } | |
1309 | ||
1310 | static void blk_tracer_start(struct trace_array *tr) | |
1311 | { | |
ad5dd549 | 1312 | blk_tracer_enabled = true; |
c71a8961 ACM |
1313 | } |
1314 | ||
1315 | static int blk_tracer_init(struct trace_array *tr) | |
1316 | { | |
1317 | blk_tr = tr; | |
1318 | blk_tracer_start(tr); | |
c71a8961 ACM |
1319 | return 0; |
1320 | } | |
1321 | ||
1322 | static void blk_tracer_stop(struct trace_array *tr) | |
1323 | { | |
ad5dd549 | 1324 | blk_tracer_enabled = false; |
c71a8961 ACM |
1325 | } |
1326 | ||
1327 | static void blk_tracer_reset(struct trace_array *tr) | |
1328 | { | |
c71a8961 ACM |
1329 | blk_tracer_stop(tr); |
1330 | } | |
1331 | ||
e4955c99 | 1332 | static const struct { |
c71a8961 | 1333 | const char *act[2]; |
ef18012b | 1334 | int (*print)(struct trace_seq *s, const struct trace_entry *ent); |
e4955c99 | 1335 | } what2act[] = { |
ef18012b | 1336 | [__BLK_TA_QUEUE] = {{ "Q", "queue" }, blk_log_generic }, |
c71a8961 ACM |
1337 | [__BLK_TA_BACKMERGE] = {{ "M", "backmerge" }, blk_log_generic }, |
1338 | [__BLK_TA_FRONTMERGE] = {{ "F", "frontmerge" }, blk_log_generic }, | |
1339 | [__BLK_TA_GETRQ] = {{ "G", "getrq" }, blk_log_generic }, | |
1340 | [__BLK_TA_SLEEPRQ] = {{ "S", "sleeprq" }, blk_log_generic }, | |
1341 | [__BLK_TA_REQUEUE] = {{ "R", "requeue" }, blk_log_with_error }, | |
1342 | [__BLK_TA_ISSUE] = {{ "D", "issue" }, blk_log_generic }, | |
1343 | [__BLK_TA_COMPLETE] = {{ "C", "complete" }, blk_log_with_error }, | |
1344 | [__BLK_TA_PLUG] = {{ "P", "plug" }, blk_log_plug }, | |
1345 | [__BLK_TA_UNPLUG_IO] = {{ "U", "unplug_io" }, blk_log_unplug }, | |
1346 | [__BLK_TA_UNPLUG_TIMER] = {{ "UT", "unplug_timer" }, blk_log_unplug }, | |
1347 | [__BLK_TA_INSERT] = {{ "I", "insert" }, blk_log_generic }, | |
1348 | [__BLK_TA_SPLIT] = {{ "X", "split" }, blk_log_split }, | |
1349 | [__BLK_TA_BOUNCE] = {{ "B", "bounce" }, blk_log_generic }, | |
1350 | [__BLK_TA_REMAP] = {{ "A", "remap" }, blk_log_remap }, | |
1351 | }; | |
1352 | ||
b6a4b0c3 LZ |
1353 | static enum print_line_t print_one_line(struct trace_iterator *iter, |
1354 | bool classic) | |
c71a8961 | 1355 | { |
2c9b238e | 1356 | struct trace_seq *s = &iter->seq; |
b6a4b0c3 LZ |
1357 | const struct blk_io_trace *t; |
1358 | u16 what; | |
c71a8961 | 1359 | int ret; |
b6a4b0c3 LZ |
1360 | bool long_act; |
1361 | blk_log_action_t *log_action; | |
c71a8961 | 1362 | |
b6a4b0c3 LZ |
1363 | t = te_blk_io_trace(iter->ent); |
1364 | what = t->action & ((1 << BLK_TC_SHIFT) - 1); | |
1365 | long_act = !!(trace_flags & TRACE_ITER_VERBOSE); | |
1366 | log_action = classic ? &blk_log_action_classic : &blk_log_action; | |
08a06b83 | 1367 | |
18cea459 LZ |
1368 | if (t->action == BLK_TN_MESSAGE) { |
1369 | ret = log_action(iter, long_act ? "message" : "m"); | |
1370 | if (ret) | |
1371 | ret = blk_log_msg(s, iter->ent); | |
1372 | goto out; | |
1373 | } | |
1374 | ||
eb08f8eb | 1375 | if (unlikely(what == 0 || what >= ARRAY_SIZE(what2act))) |
b78825d6 | 1376 | ret = trace_seq_printf(s, "Unknown action %x\n", what); |
c71a8961 | 1377 | else { |
b6a4b0c3 | 1378 | ret = log_action(iter, what2act[what].act[long_act]); |
c71a8961 | 1379 | if (ret) |
2c9b238e | 1380 | ret = what2act[what].print(s, iter->ent); |
c71a8961 | 1381 | } |
18cea459 | 1382 | out: |
c71a8961 ACM |
1383 | return ret ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; |
1384 | } | |
1385 | ||
b6a4b0c3 | 1386 | static enum print_line_t blk_trace_event_print(struct trace_iterator *iter, |
a9a57763 | 1387 | int flags, struct trace_event *event) |
b6a4b0c3 | 1388 | { |
b6a4b0c3 LZ |
1389 | return print_one_line(iter, false); |
1390 | } | |
1391 | ||
08a06b83 ACM |
1392 | static int blk_trace_synthesize_old_trace(struct trace_iterator *iter) |
1393 | { | |
1394 | struct trace_seq *s = &iter->seq; | |
1395 | struct blk_io_trace *t = (struct blk_io_trace *)iter->ent; | |
1396 | const int offset = offsetof(struct blk_io_trace, sector); | |
1397 | struct blk_io_trace old = { | |
1398 | .magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION, | |
6c051ce0 | 1399 | .time = iter->ts, |
08a06b83 ACM |
1400 | }; |
1401 | ||
1402 | if (!trace_seq_putmem(s, &old, offset)) | |
1403 | return 0; | |
1404 | return trace_seq_putmem(s, &t->sector, | |
1405 | sizeof(old) - offset + t->pdu_len); | |
1406 | } | |
1407 | ||
ae7462b4 | 1408 | static enum print_line_t |
a9a57763 SR |
1409 | blk_trace_event_print_binary(struct trace_iterator *iter, int flags, |
1410 | struct trace_event *event) | |
08a06b83 ACM |
1411 | { |
1412 | return blk_trace_synthesize_old_trace(iter) ? | |
1413 | TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; | |
1414 | } | |
1415 | ||
c71a8961 ACM |
1416 | static enum print_line_t blk_tracer_print_line(struct trace_iterator *iter) |
1417 | { | |
c71a8961 ACM |
1418 | if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) |
1419 | return TRACE_TYPE_UNHANDLED; | |
1420 | ||
b6a4b0c3 | 1421 | return print_one_line(iter, true); |
c71a8961 ACM |
1422 | } |
1423 | ||
f3948f88 LZ |
1424 | static int blk_tracer_set_flag(u32 old_flags, u32 bit, int set) |
1425 | { | |
1426 | /* don't output context-info for blk_classic output */ | |
1427 | if (bit == TRACE_BLK_OPT_CLASSIC) { | |
1428 | if (set) | |
1429 | trace_flags &= ~TRACE_ITER_CONTEXT_INFO; | |
1430 | else | |
1431 | trace_flags |= TRACE_ITER_CONTEXT_INFO; | |
1432 | } | |
1433 | return 0; | |
1434 | } | |
1435 | ||
c71a8961 ACM |
1436 | static struct tracer blk_tracer __read_mostly = { |
1437 | .name = "blk", | |
1438 | .init = blk_tracer_init, | |
1439 | .reset = blk_tracer_reset, | |
1440 | .start = blk_tracer_start, | |
1441 | .stop = blk_tracer_stop, | |
1442 | .print_header = blk_tracer_print_header, | |
1443 | .print_line = blk_tracer_print_line, | |
1444 | .flags = &blk_tracer_flags, | |
f3948f88 | 1445 | .set_flag = blk_tracer_set_flag, |
c71a8961 ACM |
1446 | }; |
1447 | ||
a9a57763 | 1448 | static struct trace_event_functions trace_blk_event_funcs = { |
c71a8961 | 1449 | .trace = blk_trace_event_print, |
08a06b83 | 1450 | .binary = blk_trace_event_print_binary, |
c71a8961 ACM |
1451 | }; |
1452 | ||
a9a57763 SR |
1453 | static struct trace_event trace_blk_event = { |
1454 | .type = TRACE_BLK, | |
1455 | .funcs = &trace_blk_event_funcs, | |
1456 | }; | |
1457 | ||
c71a8961 ACM |
1458 | static int __init init_blk_tracer(void) |
1459 | { | |
1460 | if (!register_ftrace_event(&trace_blk_event)) { | |
1461 | pr_warning("Warning: could not register block events\n"); | |
1462 | return 1; | |
1463 | } | |
1464 | ||
1465 | if (register_tracer(&blk_tracer) != 0) { | |
1466 | pr_warning("Warning: could not register the block tracer\n"); | |
1467 | unregister_ftrace_event(&trace_blk_event); | |
1468 | return 1; | |
1469 | } | |
1470 | ||
1471 | return 0; | |
1472 | } | |
1473 | ||
1474 | device_initcall(init_blk_tracer); | |
1475 | ||
1476 | static int blk_trace_remove_queue(struct request_queue *q) | |
1477 | { | |
1478 | struct blk_trace *bt; | |
1479 | ||
1480 | bt = xchg(&q->blk_trace, NULL); | |
1481 | if (bt == NULL) | |
1482 | return -EINVAL; | |
1483 | ||
17ba97e3 LZ |
1484 | if (atomic_dec_and_test(&blk_probes_ref)) |
1485 | blk_unregister_tracepoints(); | |
1486 | ||
ad5dd549 | 1487 | blk_trace_free(bt); |
c71a8961 ACM |
1488 | return 0; |
1489 | } | |
1490 | ||
1491 | /* | |
1492 | * Setup everything required to start tracing | |
1493 | */ | |
9908c309 LZ |
1494 | static int blk_trace_setup_queue(struct request_queue *q, |
1495 | struct block_device *bdev) | |
c71a8961 ACM |
1496 | { |
1497 | struct blk_trace *old_bt, *bt = NULL; | |
18cea459 | 1498 | int ret = -ENOMEM; |
c71a8961 | 1499 | |
c71a8961 ACM |
1500 | bt = kzalloc(sizeof(*bt), GFP_KERNEL); |
1501 | if (!bt) | |
15152e44 | 1502 | return -ENOMEM; |
c71a8961 | 1503 | |
18cea459 LZ |
1504 | bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); |
1505 | if (!bt->msg_data) | |
1506 | goto free_bt; | |
1507 | ||
9908c309 | 1508 | bt->dev = bdev->bd_dev; |
c71a8961 | 1509 | bt->act_mask = (u16)-1; |
9908c309 LZ |
1510 | |
1511 | blk_trace_setup_lba(bt, bdev); | |
c71a8961 ACM |
1512 | |
1513 | old_bt = xchg(&q->blk_trace, bt); | |
1514 | if (old_bt != NULL) { | |
1515 | (void)xchg(&q->blk_trace, old_bt); | |
18cea459 LZ |
1516 | ret = -EBUSY; |
1517 | goto free_bt; | |
c71a8961 | 1518 | } |
15152e44 | 1519 | |
17ba97e3 LZ |
1520 | if (atomic_inc_return(&blk_probes_ref) == 1) |
1521 | blk_register_tracepoints(); | |
c71a8961 | 1522 | return 0; |
18cea459 LZ |
1523 | |
1524 | free_bt: | |
1525 | blk_trace_free(bt); | |
1526 | return ret; | |
c71a8961 ACM |
1527 | } |
1528 | ||
1529 | /* | |
1530 | * sysfs interface to enable and configure tracing | |
1531 | */ | |
1532 | ||
c71a8961 ACM |
1533 | static ssize_t sysfs_blk_trace_attr_show(struct device *dev, |
1534 | struct device_attribute *attr, | |
1535 | char *buf); | |
1536 | static ssize_t sysfs_blk_trace_attr_store(struct device *dev, | |
1537 | struct device_attribute *attr, | |
1538 | const char *buf, size_t count); | |
1539 | #define BLK_TRACE_DEVICE_ATTR(_name) \ | |
1540 | DEVICE_ATTR(_name, S_IRUGO | S_IWUSR, \ | |
1541 | sysfs_blk_trace_attr_show, \ | |
1542 | sysfs_blk_trace_attr_store) | |
1543 | ||
cd649b8b | 1544 | static BLK_TRACE_DEVICE_ATTR(enable); |
c71a8961 ACM |
1545 | static BLK_TRACE_DEVICE_ATTR(act_mask); |
1546 | static BLK_TRACE_DEVICE_ATTR(pid); | |
1547 | static BLK_TRACE_DEVICE_ATTR(start_lba); | |
1548 | static BLK_TRACE_DEVICE_ATTR(end_lba); | |
1549 | ||
1550 | static struct attribute *blk_trace_attrs[] = { | |
1551 | &dev_attr_enable.attr, | |
1552 | &dev_attr_act_mask.attr, | |
1553 | &dev_attr_pid.attr, | |
1554 | &dev_attr_start_lba.attr, | |
1555 | &dev_attr_end_lba.attr, | |
1556 | NULL | |
1557 | }; | |
1558 | ||
1559 | struct attribute_group blk_trace_attr_group = { | |
1560 | .name = "trace", | |
1561 | .attrs = blk_trace_attrs, | |
1562 | }; | |
1563 | ||
09341997 LZ |
1564 | static const struct { |
1565 | int mask; | |
1566 | const char *str; | |
1567 | } mask_maps[] = { | |
1568 | { BLK_TC_READ, "read" }, | |
1569 | { BLK_TC_WRITE, "write" }, | |
1570 | { BLK_TC_BARRIER, "barrier" }, | |
1571 | { BLK_TC_SYNC, "sync" }, | |
1572 | { BLK_TC_QUEUE, "queue" }, | |
1573 | { BLK_TC_REQUEUE, "requeue" }, | |
1574 | { BLK_TC_ISSUE, "issue" }, | |
1575 | { BLK_TC_COMPLETE, "complete" }, | |
1576 | { BLK_TC_FS, "fs" }, | |
1577 | { BLK_TC_PC, "pc" }, | |
1578 | { BLK_TC_AHEAD, "ahead" }, | |
1579 | { BLK_TC_META, "meta" }, | |
1580 | { BLK_TC_DISCARD, "discard" }, | |
1581 | { BLK_TC_DRV_DATA, "drv_data" }, | |
1582 | }; | |
1583 | ||
1584 | static int blk_trace_str2mask(const char *str) | |
c71a8961 | 1585 | { |
09341997 | 1586 | int i; |
c71a8961 | 1587 | int mask = 0; |
9eb85125 | 1588 | char *buf, *s, *token; |
c71a8961 | 1589 | |
9eb85125 LZ |
1590 | buf = kstrdup(str, GFP_KERNEL); |
1591 | if (buf == NULL) | |
c71a8961 | 1592 | return -ENOMEM; |
9eb85125 | 1593 | s = strstrip(buf); |
c71a8961 ACM |
1594 | |
1595 | while (1) { | |
09341997 LZ |
1596 | token = strsep(&s, ","); |
1597 | if (token == NULL) | |
c71a8961 ACM |
1598 | break; |
1599 | ||
09341997 LZ |
1600 | if (*token == '\0') |
1601 | continue; | |
1602 | ||
1603 | for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { | |
1604 | if (strcasecmp(token, mask_maps[i].str) == 0) { | |
1605 | mask |= mask_maps[i].mask; | |
1606 | break; | |
1607 | } | |
1608 | } | |
1609 | if (i == ARRAY_SIZE(mask_maps)) { | |
1610 | mask = -EINVAL; | |
1611 | break; | |
1612 | } | |
c71a8961 | 1613 | } |
9eb85125 | 1614 | kfree(buf); |
c71a8961 ACM |
1615 | |
1616 | return mask; | |
1617 | } | |
1618 | ||
09341997 LZ |
1619 | static ssize_t blk_trace_mask2str(char *buf, int mask) |
1620 | { | |
1621 | int i; | |
1622 | char *p = buf; | |
1623 | ||
1624 | for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { | |
1625 | if (mask & mask_maps[i].mask) { | |
1626 | p += sprintf(p, "%s%s", | |
1627 | (p == buf) ? "" : ",", mask_maps[i].str); | |
1628 | } | |
1629 | } | |
1630 | *p++ = '\n'; | |
1631 | ||
1632 | return p - buf; | |
1633 | } | |
1634 | ||
b125130b LZ |
1635 | static struct request_queue *blk_trace_get_queue(struct block_device *bdev) |
1636 | { | |
1637 | if (bdev->bd_disk == NULL) | |
1638 | return NULL; | |
1639 | ||
1640 | return bdev_get_queue(bdev); | |
1641 | } | |
1642 | ||
c71a8961 ACM |
1643 | static ssize_t sysfs_blk_trace_attr_show(struct device *dev, |
1644 | struct device_attribute *attr, | |
1645 | char *buf) | |
1646 | { | |
1647 | struct hd_struct *p = dev_to_part(dev); | |
1648 | struct request_queue *q; | |
1649 | struct block_device *bdev; | |
1650 | ssize_t ret = -ENXIO; | |
1651 | ||
c71a8961 ACM |
1652 | bdev = bdget(part_devt(p)); |
1653 | if (bdev == NULL) | |
01b284f9 | 1654 | goto out; |
c71a8961 | 1655 | |
b125130b | 1656 | q = blk_trace_get_queue(bdev); |
c71a8961 ACM |
1657 | if (q == NULL) |
1658 | goto out_bdput; | |
b125130b | 1659 | |
c71a8961 | 1660 | mutex_lock(&bdev->bd_mutex); |
cd649b8b LZ |
1661 | |
1662 | if (attr == &dev_attr_enable) { | |
1663 | ret = sprintf(buf, "%u\n", !!q->blk_trace); | |
1664 | goto out_unlock_bdev; | |
1665 | } | |
1666 | ||
c71a8961 ACM |
1667 | if (q->blk_trace == NULL) |
1668 | ret = sprintf(buf, "disabled\n"); | |
1669 | else if (attr == &dev_attr_act_mask) | |
09341997 | 1670 | ret = blk_trace_mask2str(buf, q->blk_trace->act_mask); |
c71a8961 ACM |
1671 | else if (attr == &dev_attr_pid) |
1672 | ret = sprintf(buf, "%u\n", q->blk_trace->pid); | |
1673 | else if (attr == &dev_attr_start_lba) | |
1674 | ret = sprintf(buf, "%llu\n", q->blk_trace->start_lba); | |
1675 | else if (attr == &dev_attr_end_lba) | |
1676 | ret = sprintf(buf, "%llu\n", q->blk_trace->end_lba); | |
cd649b8b LZ |
1677 | |
1678 | out_unlock_bdev: | |
c71a8961 ACM |
1679 | mutex_unlock(&bdev->bd_mutex); |
1680 | out_bdput: | |
1681 | bdput(bdev); | |
01b284f9 | 1682 | out: |
c71a8961 ACM |
1683 | return ret; |
1684 | } | |
1685 | ||
1686 | static ssize_t sysfs_blk_trace_attr_store(struct device *dev, | |
1687 | struct device_attribute *attr, | |
1688 | const char *buf, size_t count) | |
1689 | { | |
1690 | struct block_device *bdev; | |
1691 | struct request_queue *q; | |
1692 | struct hd_struct *p; | |
1693 | u64 value; | |
09341997 | 1694 | ssize_t ret = -EINVAL; |
c71a8961 ACM |
1695 | |
1696 | if (count == 0) | |
1697 | goto out; | |
1698 | ||
1699 | if (attr == &dev_attr_act_mask) { | |
1700 | if (sscanf(buf, "%llx", &value) != 1) { | |
1701 | /* Assume it is a list of trace category names */ | |
09341997 LZ |
1702 | ret = blk_trace_str2mask(buf); |
1703 | if (ret < 0) | |
c71a8961 | 1704 | goto out; |
09341997 | 1705 | value = ret; |
c71a8961 ACM |
1706 | } |
1707 | } else if (sscanf(buf, "%llu", &value) != 1) | |
1708 | goto out; | |
1709 | ||
09341997 LZ |
1710 | ret = -ENXIO; |
1711 | ||
c71a8961 ACM |
1712 | p = dev_to_part(dev); |
1713 | bdev = bdget(part_devt(p)); | |
1714 | if (bdev == NULL) | |
01b284f9 | 1715 | goto out; |
c71a8961 | 1716 | |
b125130b | 1717 | q = blk_trace_get_queue(bdev); |
c71a8961 ACM |
1718 | if (q == NULL) |
1719 | goto out_bdput; | |
1720 | ||
1721 | mutex_lock(&bdev->bd_mutex); | |
cd649b8b LZ |
1722 | |
1723 | if (attr == &dev_attr_enable) { | |
1724 | if (value) | |
9908c309 | 1725 | ret = blk_trace_setup_queue(q, bdev); |
cd649b8b LZ |
1726 | else |
1727 | ret = blk_trace_remove_queue(q); | |
1728 | goto out_unlock_bdev; | |
1729 | } | |
1730 | ||
c71a8961 ACM |
1731 | ret = 0; |
1732 | if (q->blk_trace == NULL) | |
9908c309 | 1733 | ret = blk_trace_setup_queue(q, bdev); |
c71a8961 ACM |
1734 | |
1735 | if (ret == 0) { | |
1736 | if (attr == &dev_attr_act_mask) | |
1737 | q->blk_trace->act_mask = value; | |
1738 | else if (attr == &dev_attr_pid) | |
1739 | q->blk_trace->pid = value; | |
1740 | else if (attr == &dev_attr_start_lba) | |
1741 | q->blk_trace->start_lba = value; | |
1742 | else if (attr == &dev_attr_end_lba) | |
1743 | q->blk_trace->end_lba = value; | |
c71a8961 | 1744 | } |
cd649b8b LZ |
1745 | |
1746 | out_unlock_bdev: | |
c71a8961 ACM |
1747 | mutex_unlock(&bdev->bd_mutex); |
1748 | out_bdput: | |
1749 | bdput(bdev); | |
c71a8961 | 1750 | out: |
cd649b8b | 1751 | return ret ? ret : count; |
c71a8961 | 1752 | } |
cd649b8b | 1753 | |
1d54ad6d LZ |
1754 | int blk_trace_init_sysfs(struct device *dev) |
1755 | { | |
1756 | return sysfs_create_group(&dev->kobj, &blk_trace_attr_group); | |
1757 | } | |
1758 | ||
48c0d4d4 ZK |
1759 | void blk_trace_remove_sysfs(struct device *dev) |
1760 | { | |
1761 | sysfs_remove_group(&dev->kobj, &blk_trace_attr_group); | |
1762 | } | |
1763 | ||
55782138 LZ |
1764 | #endif /* CONFIG_BLK_DEV_IO_TRACE */ |
1765 | ||
1766 | #ifdef CONFIG_EVENT_TRACING | |
1767 | ||
1768 | void blk_dump_cmd(char *buf, struct request *rq) | |
1769 | { | |
1770 | int i, end; | |
1771 | int len = rq->cmd_len; | |
1772 | unsigned char *cmd = rq->cmd; | |
1773 | ||
33659ebb | 1774 | if (rq->cmd_type != REQ_TYPE_BLOCK_PC) { |
55782138 LZ |
1775 | buf[0] = '\0'; |
1776 | return; | |
1777 | } | |
1778 | ||
1779 | for (end = len - 1; end >= 0; end--) | |
1780 | if (cmd[end]) | |
1781 | break; | |
1782 | end++; | |
1783 | ||
1784 | for (i = 0; i < len; i++) { | |
1785 | buf += sprintf(buf, "%s%02x", i == 0 ? "" : " ", cmd[i]); | |
1786 | if (i == end && end != len - 1) { | |
1787 | sprintf(buf, " .."); | |
1788 | break; | |
1789 | } | |
1790 | } | |
1791 | } | |
1792 | ||
1793 | void blk_fill_rwbs(char *rwbs, u32 rw, int bytes) | |
1794 | { | |
1795 | int i = 0; | |
1796 | ||
1797 | if (rw & WRITE) | |
1798 | rwbs[i++] = 'W'; | |
7b6d91da | 1799 | else if (rw & REQ_DISCARD) |
55782138 LZ |
1800 | rwbs[i++] = 'D'; |
1801 | else if (bytes) | |
1802 | rwbs[i++] = 'R'; | |
1803 | else | |
1804 | rwbs[i++] = 'N'; | |
1805 | ||
7b6d91da | 1806 | if (rw & REQ_RAHEAD) |
55782138 | 1807 | rwbs[i++] = 'A'; |
7b6d91da | 1808 | if (rw & REQ_SYNC) |
55782138 | 1809 | rwbs[i++] = 'S'; |
7b6d91da | 1810 | if (rw & REQ_META) |
55782138 | 1811 | rwbs[i++] = 'M'; |
8d57a98c AH |
1812 | if (rw & REQ_SECURE) |
1813 | rwbs[i++] = 'E'; | |
55782138 LZ |
1814 | |
1815 | rwbs[i] = '\0'; | |
1816 | } | |
1817 | ||
1818 | void blk_fill_rwbs_rq(char *rwbs, struct request *rq) | |
1819 | { | |
1820 | int rw = rq->cmd_flags & 0x03; | |
1821 | int bytes; | |
1822 | ||
33659ebb | 1823 | if (rq->cmd_flags & REQ_DISCARD) |
7b6d91da | 1824 | rw |= REQ_DISCARD; |
55782138 | 1825 | |
8d57a98c AH |
1826 | if (rq->cmd_flags & REQ_SECURE) |
1827 | rw |= REQ_SECURE; | |
1828 | ||
c9059598 | 1829 | bytes = blk_rq_bytes(rq); |
55782138 LZ |
1830 | |
1831 | blk_fill_rwbs(rwbs, rw, bytes); | |
1832 | } | |
1833 | ||
1834 | #endif /* CONFIG_EVENT_TRACING */ | |
1835 |