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> |
405f5571 | 26 | #include <linux/smp_lock.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 | ||
14a73f54 | 142 | local_irq_save(flags); |
64565911 | 143 | buf = per_cpu_ptr(bt->msg_data, smp_processor_id()); |
9d5f09a4 | 144 | va_start(args, fmt); |
64565911 | 145 | n = vscnprintf(buf, BLK_TN_MAX_MSG, fmt, args); |
9d5f09a4 AB |
146 | va_end(args); |
147 | ||
64565911 | 148 | trace_note(bt, 0, BLK_TN_MESSAGE, buf, n); |
14a73f54 | 149 | local_irq_restore(flags); |
9d5f09a4 AB |
150 | } |
151 | EXPORT_SYMBOL_GPL(__trace_note_message); | |
152 | ||
2056a782 JA |
153 | static int act_log_check(struct blk_trace *bt, u32 what, sector_t sector, |
154 | pid_t pid) | |
155 | { | |
156 | if (((bt->act_mask << BLK_TC_SHIFT) & what) == 0) | |
157 | return 1; | |
d0deef5b | 158 | if (sector && (sector < bt->start_lba || sector > bt->end_lba)) |
2056a782 JA |
159 | return 1; |
160 | if (bt->pid && pid != bt->pid) | |
161 | return 1; | |
162 | ||
163 | return 0; | |
164 | } | |
165 | ||
166 | /* | |
167 | * Data direction bit lookup | |
168 | */ | |
e4955c99 LZ |
169 | static const u32 ddir_act[2] = { BLK_TC_ACT(BLK_TC_READ), |
170 | BLK_TC_ACT(BLK_TC_WRITE) }; | |
2056a782 | 171 | |
7b6d91da CH |
172 | #define BLK_TC_HARDBARRIER BLK_TC_BARRIER |
173 | #define BLK_TC_RAHEAD BLK_TC_AHEAD | |
174 | ||
35ba8f70 | 175 | /* The ilog2() calls fall out because they're constant */ |
7b6d91da CH |
176 | #define MASK_TC_BIT(rw, __name) ((rw & REQ_ ## __name) << \ |
177 | (ilog2(BLK_TC_ ## __name) + BLK_TC_SHIFT - __REQ_ ## __name)) | |
2056a782 JA |
178 | |
179 | /* | |
180 | * The worker for the various blk_add_trace*() types. Fills out a | |
181 | * blk_io_trace structure and places it in a per-cpu subbuffer. | |
182 | */ | |
5f3ea37c | 183 | static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, |
2056a782 JA |
184 | int rw, u32 what, int error, int pdu_len, void *pdu_data) |
185 | { | |
186 | struct task_struct *tsk = current; | |
c71a8961 | 187 | struct ring_buffer_event *event = NULL; |
e77405ad | 188 | struct ring_buffer *buffer = NULL; |
2056a782 | 189 | struct blk_io_trace *t; |
0a987751 | 190 | unsigned long flags = 0; |
2056a782 JA |
191 | unsigned long *sequence; |
192 | pid_t pid; | |
c71a8961 | 193 | int cpu, pc = 0; |
18cea459 | 194 | bool blk_tracer = blk_tracer_enabled; |
2056a782 | 195 | |
18cea459 | 196 | if (unlikely(bt->trace_state != Blktrace_running && !blk_tracer)) |
2056a782 JA |
197 | return; |
198 | ||
199 | what |= ddir_act[rw & WRITE]; | |
7b6d91da CH |
200 | what |= MASK_TC_BIT(rw, HARDBARRIER); |
201 | what |= MASK_TC_BIT(rw, SYNC); | |
202 | what |= MASK_TC_BIT(rw, RAHEAD); | |
35ba8f70 DW |
203 | what |= MASK_TC_BIT(rw, META); |
204 | what |= MASK_TC_BIT(rw, DISCARD); | |
2056a782 JA |
205 | |
206 | pid = tsk->pid; | |
d0deef5b | 207 | if (act_log_check(bt, what, sector, pid)) |
2056a782 | 208 | return; |
c71a8961 ACM |
209 | cpu = raw_smp_processor_id(); |
210 | ||
18cea459 | 211 | if (blk_tracer) { |
c71a8961 ACM |
212 | tracing_record_cmdline(current); |
213 | ||
e77405ad | 214 | buffer = blk_tr->buffer; |
51a763dd | 215 | pc = preempt_count(); |
e77405ad | 216 | event = trace_buffer_lock_reserve(buffer, TRACE_BLK, |
51a763dd ACM |
217 | sizeof(*t) + pdu_len, |
218 | 0, pc); | |
c71a8961 ACM |
219 | if (!event) |
220 | return; | |
51a763dd | 221 | t = ring_buffer_event_data(event); |
c71a8961 ACM |
222 | goto record_it; |
223 | } | |
2056a782 JA |
224 | |
225 | /* | |
226 | * A word about the locking here - we disable interrupts to reserve | |
227 | * some space in the relay per-cpu buffer, to prevent an irq | |
14a73f54 | 228 | * from coming in and stepping on our toes. |
2056a782 JA |
229 | */ |
230 | local_irq_save(flags); | |
231 | ||
232 | if (unlikely(tsk->btrace_seq != blktrace_seq)) | |
233 | trace_note_tsk(bt, tsk); | |
234 | ||
235 | t = relay_reserve(bt->rchan, sizeof(*t) + pdu_len); | |
236 | if (t) { | |
2056a782 JA |
237 | sequence = per_cpu_ptr(bt->sequence, cpu); |
238 | ||
239 | t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; | |
240 | t->sequence = ++(*sequence); | |
2997c8c4 | 241 | t->time = ktime_to_ns(ktime_get()); |
c71a8961 | 242 | record_it: |
08a06b83 | 243 | /* |
939b3669 ACM |
244 | * These two are not needed in ftrace as they are in the |
245 | * generic trace_entry, filled by tracing_generic_entry_update, | |
246 | * but for the trace_event->bin() synthesizer benefit we do it | |
247 | * here too. | |
248 | */ | |
249 | t->cpu = cpu; | |
250 | t->pid = pid; | |
08a06b83 | 251 | |
2056a782 JA |
252 | t->sector = sector; |
253 | t->bytes = bytes; | |
254 | t->action = what; | |
2056a782 | 255 | t->device = bt->dev; |
2056a782 JA |
256 | t->error = error; |
257 | t->pdu_len = pdu_len; | |
258 | ||
259 | if (pdu_len) | |
260 | memcpy((void *) t + sizeof(*t), pdu_data, pdu_len); | |
c71a8961 | 261 | |
18cea459 | 262 | if (blk_tracer) { |
e77405ad | 263 | trace_buffer_unlock_commit(buffer, event, 0, pc); |
c71a8961 ACM |
264 | return; |
265 | } | |
2056a782 JA |
266 | } |
267 | ||
268 | local_irq_restore(flags); | |
269 | } | |
270 | ||
2056a782 | 271 | static struct dentry *blk_tree_root; |
11a57153 | 272 | static DEFINE_MUTEX(blk_tree_mutex); |
2056a782 | 273 | |
ad5dd549 | 274 | static void blk_trace_free(struct blk_trace *bt) |
2056a782 | 275 | { |
02c62304 | 276 | debugfs_remove(bt->msg_file); |
2056a782 | 277 | debugfs_remove(bt->dropped_file); |
f48fc4d3 | 278 | relay_close(bt->rchan); |
39cbb602 | 279 | debugfs_remove(bt->dir); |
2056a782 | 280 | free_percpu(bt->sequence); |
64565911 | 281 | free_percpu(bt->msg_data); |
2056a782 | 282 | kfree(bt); |
ad5dd549 LZ |
283 | } |
284 | ||
285 | static void blk_trace_cleanup(struct blk_trace *bt) | |
286 | { | |
287 | blk_trace_free(bt); | |
5f3ea37c ACM |
288 | if (atomic_dec_and_test(&blk_probes_ref)) |
289 | blk_unregister_tracepoints(); | |
2056a782 JA |
290 | } |
291 | ||
6da127ad | 292 | int blk_trace_remove(struct request_queue *q) |
2056a782 JA |
293 | { |
294 | struct blk_trace *bt; | |
295 | ||
296 | bt = xchg(&q->blk_trace, NULL); | |
297 | if (!bt) | |
298 | return -EINVAL; | |
299 | ||
55547204 | 300 | if (bt->trace_state != Blktrace_running) |
2056a782 JA |
301 | blk_trace_cleanup(bt); |
302 | ||
303 | return 0; | |
304 | } | |
6da127ad | 305 | EXPORT_SYMBOL_GPL(blk_trace_remove); |
2056a782 JA |
306 | |
307 | static int blk_dropped_open(struct inode *inode, struct file *filp) | |
308 | { | |
8e18e294 | 309 | filp->private_data = inode->i_private; |
2056a782 JA |
310 | |
311 | return 0; | |
312 | } | |
313 | ||
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 JA |
326 | .owner = THIS_MODULE, |
327 | .open = blk_dropped_open, | |
328 | .read = blk_dropped_read, | |
329 | }; | |
330 | ||
02c62304 AB |
331 | static int blk_msg_open(struct inode *inode, struct file *filp) |
332 | { | |
333 | filp->private_data = inode->i_private; | |
334 | ||
335 | return 0; | |
336 | } | |
337 | ||
338 | static ssize_t blk_msg_write(struct file *filp, const char __user *buffer, | |
339 | size_t count, loff_t *ppos) | |
340 | { | |
341 | char *msg; | |
342 | struct blk_trace *bt; | |
343 | ||
7635b03a | 344 | if (count >= BLK_TN_MAX_MSG) |
02c62304 AB |
345 | return -EINVAL; |
346 | ||
a4b3ada8 | 347 | msg = kmalloc(count + 1, GFP_KERNEL); |
02c62304 AB |
348 | if (msg == NULL) |
349 | return -ENOMEM; | |
350 | ||
351 | if (copy_from_user(msg, buffer, count)) { | |
352 | kfree(msg); | |
353 | return -EFAULT; | |
354 | } | |
355 | ||
a4b3ada8 | 356 | msg[count] = '\0'; |
02c62304 AB |
357 | bt = filp->private_data; |
358 | __trace_note_message(bt, "%s", msg); | |
359 | kfree(msg); | |
360 | ||
361 | return count; | |
362 | } | |
363 | ||
364 | static const struct file_operations blk_msg_fops = { | |
365 | .owner = THIS_MODULE, | |
366 | .open = blk_msg_open, | |
367 | .write = blk_msg_write, | |
368 | }; | |
369 | ||
2056a782 JA |
370 | /* |
371 | * Keep track of how many times we encountered a full subbuffer, to aid | |
372 | * the user space app in telling how many lost events there were. | |
373 | */ | |
374 | static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf, | |
375 | void *prev_subbuf, size_t prev_padding) | |
376 | { | |
377 | struct blk_trace *bt; | |
378 | ||
379 | if (!relay_buf_full(buf)) | |
380 | return 1; | |
381 | ||
382 | bt = buf->chan->private_data; | |
383 | atomic_inc(&bt->dropped); | |
384 | return 0; | |
385 | } | |
386 | ||
387 | static int blk_remove_buf_file_callback(struct dentry *dentry) | |
388 | { | |
389 | debugfs_remove(dentry); | |
f48fc4d3 | 390 | |
2056a782 JA |
391 | return 0; |
392 | } | |
393 | ||
394 | static struct dentry *blk_create_buf_file_callback(const char *filename, | |
395 | struct dentry *parent, | |
396 | int mode, | |
397 | struct rchan_buf *buf, | |
398 | int *is_global) | |
399 | { | |
400 | return debugfs_create_file(filename, mode, parent, buf, | |
401 | &relay_file_operations); | |
402 | } | |
403 | ||
404 | static struct rchan_callbacks blk_relay_callbacks = { | |
405 | .subbuf_start = blk_subbuf_start_callback, | |
406 | .create_buf_file = blk_create_buf_file_callback, | |
407 | .remove_buf_file = blk_remove_buf_file_callback, | |
408 | }; | |
409 | ||
9908c309 LZ |
410 | static void blk_trace_setup_lba(struct blk_trace *bt, |
411 | struct block_device *bdev) | |
412 | { | |
413 | struct hd_struct *part = NULL; | |
414 | ||
415 | if (bdev) | |
416 | part = bdev->bd_part; | |
417 | ||
418 | if (part) { | |
419 | bt->start_lba = part->start_sect; | |
420 | bt->end_lba = part->start_sect + part->nr_sects; | |
421 | } else { | |
422 | bt->start_lba = 0; | |
423 | bt->end_lba = -1ULL; | |
424 | } | |
425 | } | |
426 | ||
2056a782 JA |
427 | /* |
428 | * Setup everything required to start tracing | |
429 | */ | |
6da127ad | 430 | int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, |
d0deef5b SD |
431 | struct block_device *bdev, |
432 | struct blk_user_trace_setup *buts) | |
2056a782 | 433 | { |
2056a782 JA |
434 | struct blk_trace *old_bt, *bt = NULL; |
435 | struct dentry *dir = NULL; | |
2056a782 JA |
436 | int ret, i; |
437 | ||
171044d4 | 438 | if (!buts->buf_size || !buts->buf_nr) |
2056a782 JA |
439 | return -EINVAL; |
440 | ||
0497b345 JA |
441 | strncpy(buts->name, name, BLKTRACE_BDEV_SIZE); |
442 | buts->name[BLKTRACE_BDEV_SIZE - 1] = '\0'; | |
2056a782 JA |
443 | |
444 | /* | |
445 | * some device names have larger paths - convert the slashes | |
446 | * to underscores for this to work as expected | |
447 | */ | |
171044d4 AB |
448 | for (i = 0; i < strlen(buts->name); i++) |
449 | if (buts->name[i] == '/') | |
450 | buts->name[i] = '_'; | |
2056a782 | 451 | |
2056a782 JA |
452 | bt = kzalloc(sizeof(*bt), GFP_KERNEL); |
453 | if (!bt) | |
ad5dd549 | 454 | return -ENOMEM; |
2056a782 | 455 | |
ad5dd549 | 456 | ret = -ENOMEM; |
2056a782 JA |
457 | bt->sequence = alloc_percpu(unsigned long); |
458 | if (!bt->sequence) | |
459 | goto err; | |
460 | ||
313e458f | 461 | bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); |
64565911 JA |
462 | if (!bt->msg_data) |
463 | goto err; | |
464 | ||
2056a782 | 465 | ret = -ENOENT; |
f48fc4d3 | 466 | |
b5230b56 | 467 | mutex_lock(&blk_tree_mutex); |
f48fc4d3 JA |
468 | if (!blk_tree_root) { |
469 | blk_tree_root = debugfs_create_dir("block", NULL); | |
b5230b56 LZ |
470 | if (!blk_tree_root) { |
471 | mutex_unlock(&blk_tree_mutex); | |
1a17662e | 472 | goto err; |
b5230b56 | 473 | } |
f48fc4d3 | 474 | } |
b5230b56 | 475 | mutex_unlock(&blk_tree_mutex); |
f48fc4d3 JA |
476 | |
477 | dir = debugfs_create_dir(buts->name, blk_tree_root); | |
478 | ||
2056a782 JA |
479 | if (!dir) |
480 | goto err; | |
481 | ||
482 | bt->dir = dir; | |
6da127ad | 483 | bt->dev = dev; |
2056a782 JA |
484 | atomic_set(&bt->dropped, 0); |
485 | ||
486 | ret = -EIO; | |
939b3669 ACM |
487 | bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt, |
488 | &blk_dropped_fops); | |
2056a782 JA |
489 | if (!bt->dropped_file) |
490 | goto err; | |
491 | ||
02c62304 AB |
492 | bt->msg_file = debugfs_create_file("msg", 0222, dir, bt, &blk_msg_fops); |
493 | if (!bt->msg_file) | |
494 | goto err; | |
495 | ||
171044d4 AB |
496 | bt->rchan = relay_open("trace", dir, buts->buf_size, |
497 | buts->buf_nr, &blk_relay_callbacks, bt); | |
2056a782 JA |
498 | if (!bt->rchan) |
499 | goto err; | |
2056a782 | 500 | |
171044d4 | 501 | bt->act_mask = buts->act_mask; |
2056a782 JA |
502 | if (!bt->act_mask) |
503 | bt->act_mask = (u16) -1; | |
504 | ||
9908c309 | 505 | blk_trace_setup_lba(bt, bdev); |
2056a782 | 506 | |
d0deef5b SD |
507 | /* overwrite with user settings */ |
508 | if (buts->start_lba) | |
509 | bt->start_lba = buts->start_lba; | |
510 | if (buts->end_lba) | |
511 | bt->end_lba = buts->end_lba; | |
512 | ||
171044d4 | 513 | bt->pid = buts->pid; |
2056a782 JA |
514 | bt->trace_state = Blktrace_setup; |
515 | ||
516 | ret = -EBUSY; | |
517 | old_bt = xchg(&q->blk_trace, bt); | |
518 | if (old_bt) { | |
519 | (void) xchg(&q->blk_trace, old_bt); | |
520 | goto err; | |
521 | } | |
522 | ||
17ba97e3 | 523 | if (atomic_inc_return(&blk_probes_ref) == 1) |
cbe28296 LZ |
524 | blk_register_tracepoints(); |
525 | ||
2056a782 JA |
526 | return 0; |
527 | err: | |
ad5dd549 | 528 | blk_trace_free(bt); |
2056a782 JA |
529 | return ret; |
530 | } | |
171044d4 | 531 | |
6da127ad | 532 | int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, |
d0deef5b | 533 | struct block_device *bdev, |
6da127ad | 534 | char __user *arg) |
171044d4 AB |
535 | { |
536 | struct blk_user_trace_setup buts; | |
537 | int ret; | |
538 | ||
539 | ret = copy_from_user(&buts, arg, sizeof(buts)); | |
540 | if (ret) | |
541 | return -EFAULT; | |
542 | ||
d0deef5b | 543 | ret = do_blk_trace_setup(q, name, dev, bdev, &buts); |
171044d4 AB |
544 | if (ret) |
545 | return ret; | |
546 | ||
9a8c28c8 DM |
547 | if (copy_to_user(arg, &buts, sizeof(buts))) { |
548 | blk_trace_remove(q); | |
171044d4 | 549 | return -EFAULT; |
9a8c28c8 | 550 | } |
171044d4 AB |
551 | return 0; |
552 | } | |
6da127ad | 553 | EXPORT_SYMBOL_GPL(blk_trace_setup); |
2056a782 | 554 | |
62c2a7d9 AB |
555 | #if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64) |
556 | static int compat_blk_trace_setup(struct request_queue *q, char *name, | |
557 | dev_t dev, struct block_device *bdev, | |
558 | char __user *arg) | |
559 | { | |
560 | struct blk_user_trace_setup buts; | |
561 | struct compat_blk_user_trace_setup cbuts; | |
562 | int ret; | |
563 | ||
564 | if (copy_from_user(&cbuts, arg, sizeof(cbuts))) | |
565 | return -EFAULT; | |
566 | ||
567 | buts = (struct blk_user_trace_setup) { | |
568 | .act_mask = cbuts.act_mask, | |
569 | .buf_size = cbuts.buf_size, | |
570 | .buf_nr = cbuts.buf_nr, | |
571 | .start_lba = cbuts.start_lba, | |
572 | .end_lba = cbuts.end_lba, | |
573 | .pid = cbuts.pid, | |
574 | }; | |
575 | memcpy(&buts.name, &cbuts.name, 32); | |
576 | ||
577 | ret = do_blk_trace_setup(q, name, dev, bdev, &buts); | |
578 | if (ret) | |
579 | return ret; | |
580 | ||
581 | if (copy_to_user(arg, &buts.name, 32)) { | |
582 | blk_trace_remove(q); | |
583 | return -EFAULT; | |
584 | } | |
585 | ||
586 | return 0; | |
587 | } | |
588 | #endif | |
589 | ||
6da127ad | 590 | int blk_trace_startstop(struct request_queue *q, int start) |
2056a782 | 591 | { |
2056a782 | 592 | int ret; |
939b3669 | 593 | struct blk_trace *bt = q->blk_trace; |
2056a782 | 594 | |
939b3669 | 595 | if (bt == NULL) |
2056a782 JA |
596 | return -EINVAL; |
597 | ||
598 | /* | |
599 | * For starting a trace, we can transition from a setup or stopped | |
600 | * trace. For stopping a trace, the state must be running | |
601 | */ | |
602 | ret = -EINVAL; | |
603 | if (start) { | |
604 | if (bt->trace_state == Blktrace_setup || | |
605 | bt->trace_state == Blktrace_stopped) { | |
606 | blktrace_seq++; | |
607 | smp_mb(); | |
608 | bt->trace_state = Blktrace_running; | |
be1c6341 OK |
609 | |
610 | trace_note_time(bt); | |
2056a782 JA |
611 | ret = 0; |
612 | } | |
613 | } else { | |
614 | if (bt->trace_state == Blktrace_running) { | |
615 | bt->trace_state = Blktrace_stopped; | |
616 | relay_flush(bt->rchan); | |
617 | ret = 0; | |
618 | } | |
619 | } | |
620 | ||
621 | return ret; | |
622 | } | |
6da127ad | 623 | EXPORT_SYMBOL_GPL(blk_trace_startstop); |
2056a782 JA |
624 | |
625 | /** | |
626 | * blk_trace_ioctl: - handle the ioctls associated with tracing | |
627 | * @bdev: the block device | |
ef18012b | 628 | * @cmd: the ioctl cmd |
2056a782 JA |
629 | * @arg: the argument data, if any |
630 | * | |
631 | **/ | |
632 | int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) | |
633 | { | |
165125e1 | 634 | struct request_queue *q; |
2056a782 | 635 | int ret, start = 0; |
6da127ad | 636 | char b[BDEVNAME_SIZE]; |
2056a782 JA |
637 | |
638 | q = bdev_get_queue(bdev); | |
639 | if (!q) | |
640 | return -ENXIO; | |
641 | ||
62c2a7d9 | 642 | lock_kernel(); |
2056a782 JA |
643 | mutex_lock(&bdev->bd_mutex); |
644 | ||
645 | switch (cmd) { | |
646 | case BLKTRACESETUP: | |
f36f21ec | 647 | bdevname(bdev, b); |
d0deef5b | 648 | ret = blk_trace_setup(q, b, bdev->bd_dev, bdev, arg); |
2056a782 | 649 | break; |
62c2a7d9 AB |
650 | #if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64) |
651 | case BLKTRACESETUP32: | |
652 | bdevname(bdev, b); | |
653 | ret = compat_blk_trace_setup(q, b, bdev->bd_dev, bdev, arg); | |
654 | break; | |
655 | #endif | |
2056a782 JA |
656 | case BLKTRACESTART: |
657 | start = 1; | |
658 | case BLKTRACESTOP: | |
659 | ret = blk_trace_startstop(q, start); | |
660 | break; | |
661 | case BLKTRACETEARDOWN: | |
662 | ret = blk_trace_remove(q); | |
663 | break; | |
664 | default: | |
665 | ret = -ENOTTY; | |
666 | break; | |
667 | } | |
668 | ||
669 | mutex_unlock(&bdev->bd_mutex); | |
62c2a7d9 | 670 | unlock_kernel(); |
2056a782 JA |
671 | return ret; |
672 | } | |
673 | ||
674 | /** | |
675 | * blk_trace_shutdown: - stop and cleanup trace structures | |
676 | * @q: the request queue associated with the device | |
677 | * | |
678 | **/ | |
165125e1 | 679 | void blk_trace_shutdown(struct request_queue *q) |
2056a782 | 680 | { |
6c5c9341 AD |
681 | if (q->blk_trace) { |
682 | blk_trace_startstop(q, 0); | |
683 | blk_trace_remove(q); | |
684 | } | |
2056a782 | 685 | } |
5f3ea37c ACM |
686 | |
687 | /* | |
688 | * blktrace probes | |
689 | */ | |
690 | ||
691 | /** | |
692 | * blk_add_trace_rq - Add a trace for a request oriented action | |
693 | * @q: queue the io is for | |
694 | * @rq: the source request | |
695 | * @what: the action | |
696 | * | |
697 | * Description: | |
698 | * Records an action against a request. Will log the bio offset + size. | |
699 | * | |
700 | **/ | |
701 | static void blk_add_trace_rq(struct request_queue *q, struct request *rq, | |
702 | u32 what) | |
703 | { | |
704 | struct blk_trace *bt = q->blk_trace; | |
705 | int rw = rq->cmd_flags & 0x03; | |
706 | ||
707 | if (likely(!bt)) | |
708 | return; | |
709 | ||
33659ebb | 710 | if (rq->cmd_flags & REQ_DISCARD) |
7b6d91da | 711 | rw |= REQ_DISCARD; |
5f3ea37c | 712 | |
8d57a98c AH |
713 | if (rq->cmd_flags & REQ_SECURE) |
714 | rw |= REQ_SECURE; | |
715 | ||
33659ebb | 716 | if (rq->cmd_type == REQ_TYPE_BLOCK_PC) { |
5f3ea37c | 717 | what |= BLK_TC_ACT(BLK_TC_PC); |
2e46e8b2 TH |
718 | __blk_add_trace(bt, 0, blk_rq_bytes(rq), rw, |
719 | what, rq->errors, rq->cmd_len, rq->cmd); | |
5f3ea37c ACM |
720 | } else { |
721 | what |= BLK_TC_ACT(BLK_TC_FS); | |
2e46e8b2 TH |
722 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), rw, |
723 | what, rq->errors, 0, NULL); | |
5f3ea37c ACM |
724 | } |
725 | } | |
726 | ||
38516ab5 SR |
727 | static void blk_add_trace_rq_abort(void *ignore, |
728 | struct request_queue *q, struct request *rq) | |
5f3ea37c ACM |
729 | { |
730 | blk_add_trace_rq(q, rq, BLK_TA_ABORT); | |
731 | } | |
732 | ||
38516ab5 SR |
733 | static void blk_add_trace_rq_insert(void *ignore, |
734 | struct request_queue *q, struct request *rq) | |
5f3ea37c ACM |
735 | { |
736 | blk_add_trace_rq(q, rq, BLK_TA_INSERT); | |
737 | } | |
738 | ||
38516ab5 SR |
739 | static void blk_add_trace_rq_issue(void *ignore, |
740 | struct request_queue *q, struct request *rq) | |
5f3ea37c ACM |
741 | { |
742 | blk_add_trace_rq(q, rq, BLK_TA_ISSUE); | |
743 | } | |
744 | ||
38516ab5 SR |
745 | static void blk_add_trace_rq_requeue(void *ignore, |
746 | struct request_queue *q, | |
939b3669 | 747 | struct request *rq) |
5f3ea37c ACM |
748 | { |
749 | blk_add_trace_rq(q, rq, BLK_TA_REQUEUE); | |
750 | } | |
751 | ||
38516ab5 SR |
752 | static void blk_add_trace_rq_complete(void *ignore, |
753 | struct request_queue *q, | |
939b3669 | 754 | struct request *rq) |
5f3ea37c ACM |
755 | { |
756 | blk_add_trace_rq(q, rq, BLK_TA_COMPLETE); | |
757 | } | |
758 | ||
759 | /** | |
760 | * blk_add_trace_bio - Add a trace for a bio oriented action | |
761 | * @q: queue the io is for | |
762 | * @bio: the source bio | |
763 | * @what: the action | |
764 | * | |
765 | * Description: | |
766 | * Records an action against a bio. Will log the bio offset + size. | |
767 | * | |
768 | **/ | |
769 | static void blk_add_trace_bio(struct request_queue *q, struct bio *bio, | |
770 | u32 what) | |
771 | { | |
772 | struct blk_trace *bt = q->blk_trace; | |
773 | ||
774 | if (likely(!bt)) | |
775 | return; | |
776 | ||
777 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, | |
778 | !bio_flagged(bio, BIO_UPTODATE), 0, NULL); | |
779 | } | |
780 | ||
38516ab5 SR |
781 | static void blk_add_trace_bio_bounce(void *ignore, |
782 | struct request_queue *q, struct bio *bio) | |
5f3ea37c ACM |
783 | { |
784 | blk_add_trace_bio(q, bio, BLK_TA_BOUNCE); | |
785 | } | |
786 | ||
38516ab5 SR |
787 | static void blk_add_trace_bio_complete(void *ignore, |
788 | struct request_queue *q, struct bio *bio) | |
5f3ea37c ACM |
789 | { |
790 | blk_add_trace_bio(q, bio, BLK_TA_COMPLETE); | |
791 | } | |
792 | ||
38516ab5 SR |
793 | static void blk_add_trace_bio_backmerge(void *ignore, |
794 | struct request_queue *q, | |
939b3669 | 795 | struct bio *bio) |
5f3ea37c ACM |
796 | { |
797 | blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE); | |
798 | } | |
799 | ||
38516ab5 SR |
800 | static void blk_add_trace_bio_frontmerge(void *ignore, |
801 | struct request_queue *q, | |
939b3669 | 802 | struct bio *bio) |
5f3ea37c ACM |
803 | { |
804 | blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE); | |
805 | } | |
806 | ||
38516ab5 SR |
807 | static void blk_add_trace_bio_queue(void *ignore, |
808 | struct request_queue *q, struct bio *bio) | |
5f3ea37c ACM |
809 | { |
810 | blk_add_trace_bio(q, bio, BLK_TA_QUEUE); | |
811 | } | |
812 | ||
38516ab5 SR |
813 | static void blk_add_trace_getrq(void *ignore, |
814 | struct request_queue *q, | |
939b3669 | 815 | struct bio *bio, int rw) |
5f3ea37c ACM |
816 | { |
817 | if (bio) | |
818 | blk_add_trace_bio(q, bio, BLK_TA_GETRQ); | |
819 | else { | |
820 | struct blk_trace *bt = q->blk_trace; | |
821 | ||
822 | if (bt) | |
823 | __blk_add_trace(bt, 0, 0, rw, BLK_TA_GETRQ, 0, 0, NULL); | |
824 | } | |
825 | } | |
826 | ||
827 | ||
38516ab5 SR |
828 | static void blk_add_trace_sleeprq(void *ignore, |
829 | struct request_queue *q, | |
939b3669 | 830 | struct bio *bio, int rw) |
5f3ea37c ACM |
831 | { |
832 | if (bio) | |
833 | blk_add_trace_bio(q, bio, BLK_TA_SLEEPRQ); | |
834 | else { | |
835 | struct blk_trace *bt = q->blk_trace; | |
836 | ||
837 | if (bt) | |
939b3669 ACM |
838 | __blk_add_trace(bt, 0, 0, rw, BLK_TA_SLEEPRQ, |
839 | 0, 0, NULL); | |
5f3ea37c ACM |
840 | } |
841 | } | |
842 | ||
38516ab5 | 843 | static void blk_add_trace_plug(void *ignore, struct request_queue *q) |
5f3ea37c ACM |
844 | { |
845 | struct blk_trace *bt = q->blk_trace; | |
846 | ||
847 | if (bt) | |
848 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_PLUG, 0, 0, NULL); | |
849 | } | |
850 | ||
38516ab5 | 851 | static void blk_add_trace_unplug_io(void *ignore, struct request_queue *q) |
5f3ea37c ACM |
852 | { |
853 | struct blk_trace *bt = q->blk_trace; | |
854 | ||
855 | if (bt) { | |
856 | unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; | |
857 | __be64 rpdu = cpu_to_be64(pdu); | |
858 | ||
859 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_IO, 0, | |
860 | sizeof(rpdu), &rpdu); | |
861 | } | |
862 | } | |
863 | ||
38516ab5 | 864 | static void blk_add_trace_unplug_timer(void *ignore, struct request_queue *q) |
5f3ea37c ACM |
865 | { |
866 | struct blk_trace *bt = q->blk_trace; | |
867 | ||
868 | if (bt) { | |
869 | unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; | |
870 | __be64 rpdu = cpu_to_be64(pdu); | |
871 | ||
872 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_TIMER, 0, | |
873 | sizeof(rpdu), &rpdu); | |
874 | } | |
875 | } | |
876 | ||
38516ab5 SR |
877 | static void blk_add_trace_split(void *ignore, |
878 | struct request_queue *q, struct bio *bio, | |
5f3ea37c ACM |
879 | unsigned int pdu) |
880 | { | |
881 | struct blk_trace *bt = q->blk_trace; | |
882 | ||
883 | if (bt) { | |
884 | __be64 rpdu = cpu_to_be64(pdu); | |
885 | ||
886 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, | |
887 | BLK_TA_SPLIT, !bio_flagged(bio, BIO_UPTODATE), | |
888 | sizeof(rpdu), &rpdu); | |
889 | } | |
890 | } | |
891 | ||
892 | /** | |
893 | * blk_add_trace_remap - Add a trace for a remap operation | |
546cf44a | 894 | * @ignore: trace callback data parameter (not used) |
5f3ea37c ACM |
895 | * @q: queue the io is for |
896 | * @bio: the source bio | |
897 | * @dev: target device | |
a42aaa3b | 898 | * @from: source sector |
5f3ea37c ACM |
899 | * |
900 | * Description: | |
901 | * Device mapper or raid target sometimes need to split a bio because | |
902 | * it spans a stripe (or similar). Add a trace for that action. | |
903 | * | |
904 | **/ | |
38516ab5 SR |
905 | static void blk_add_trace_remap(void *ignore, |
906 | struct request_queue *q, struct bio *bio, | |
907 | dev_t dev, sector_t from) | |
5f3ea37c ACM |
908 | { |
909 | struct blk_trace *bt = q->blk_trace; | |
910 | struct blk_io_trace_remap r; | |
911 | ||
912 | if (likely(!bt)) | |
913 | return; | |
914 | ||
a42aaa3b AB |
915 | r.device_from = cpu_to_be32(dev); |
916 | r.device_to = cpu_to_be32(bio->bi_bdev->bd_dev); | |
917 | r.sector_from = cpu_to_be64(from); | |
5f3ea37c | 918 | |
22a7c31a AB |
919 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, |
920 | BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), | |
921 | sizeof(r), &r); | |
5f3ea37c ACM |
922 | } |
923 | ||
b0da3f0d JN |
924 | /** |
925 | * blk_add_trace_rq_remap - Add a trace for a request-remap operation | |
546cf44a | 926 | * @ignore: trace callback data parameter (not used) |
b0da3f0d JN |
927 | * @q: queue the io is for |
928 | * @rq: the source request | |
929 | * @dev: target device | |
930 | * @from: source sector | |
931 | * | |
932 | * Description: | |
933 | * Device mapper remaps request to other devices. | |
934 | * Add a trace for that action. | |
935 | * | |
936 | **/ | |
38516ab5 SR |
937 | static void blk_add_trace_rq_remap(void *ignore, |
938 | struct request_queue *q, | |
b0da3f0d JN |
939 | struct request *rq, dev_t dev, |
940 | sector_t from) | |
941 | { | |
942 | struct blk_trace *bt = q->blk_trace; | |
943 | struct blk_io_trace_remap r; | |
944 | ||
945 | if (likely(!bt)) | |
946 | return; | |
947 | ||
948 | r.device_from = cpu_to_be32(dev); | |
949 | r.device_to = cpu_to_be32(disk_devt(rq->rq_disk)); | |
950 | r.sector_from = cpu_to_be64(from); | |
951 | ||
952 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), | |
953 | rq_data_dir(rq), BLK_TA_REMAP, !!rq->errors, | |
954 | sizeof(r), &r); | |
955 | } | |
956 | ||
5f3ea37c ACM |
957 | /** |
958 | * blk_add_driver_data - Add binary message with driver-specific data | |
959 | * @q: queue the io is for | |
960 | * @rq: io request | |
961 | * @data: driver-specific data | |
962 | * @len: length of driver-specific data | |
963 | * | |
964 | * Description: | |
965 | * Some drivers might want to write driver-specific data per request. | |
966 | * | |
967 | **/ | |
968 | void blk_add_driver_data(struct request_queue *q, | |
969 | struct request *rq, | |
970 | void *data, size_t len) | |
971 | { | |
972 | struct blk_trace *bt = q->blk_trace; | |
973 | ||
974 | if (likely(!bt)) | |
975 | return; | |
976 | ||
33659ebb | 977 | if (rq->cmd_type == REQ_TYPE_BLOCK_PC) |
2e46e8b2 TH |
978 | __blk_add_trace(bt, 0, blk_rq_bytes(rq), 0, |
979 | BLK_TA_DRV_DATA, rq->errors, len, data); | |
5f3ea37c | 980 | else |
2e46e8b2 TH |
981 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), 0, |
982 | BLK_TA_DRV_DATA, rq->errors, len, data); | |
5f3ea37c ACM |
983 | } |
984 | EXPORT_SYMBOL_GPL(blk_add_driver_data); | |
985 | ||
3c289ba7 | 986 | static void blk_register_tracepoints(void) |
5f3ea37c ACM |
987 | { |
988 | int ret; | |
989 | ||
38516ab5 | 990 | ret = register_trace_block_rq_abort(blk_add_trace_rq_abort, NULL); |
5f3ea37c | 991 | WARN_ON(ret); |
38516ab5 | 992 | ret = register_trace_block_rq_insert(blk_add_trace_rq_insert, NULL); |
5f3ea37c | 993 | WARN_ON(ret); |
38516ab5 | 994 | ret = register_trace_block_rq_issue(blk_add_trace_rq_issue, NULL); |
5f3ea37c | 995 | WARN_ON(ret); |
38516ab5 | 996 | ret = register_trace_block_rq_requeue(blk_add_trace_rq_requeue, NULL); |
5f3ea37c | 997 | WARN_ON(ret); |
38516ab5 | 998 | ret = register_trace_block_rq_complete(blk_add_trace_rq_complete, NULL); |
5f3ea37c | 999 | WARN_ON(ret); |
38516ab5 | 1000 | ret = register_trace_block_bio_bounce(blk_add_trace_bio_bounce, NULL); |
5f3ea37c | 1001 | WARN_ON(ret); |
38516ab5 | 1002 | ret = register_trace_block_bio_complete(blk_add_trace_bio_complete, NULL); |
5f3ea37c | 1003 | WARN_ON(ret); |
38516ab5 | 1004 | ret = register_trace_block_bio_backmerge(blk_add_trace_bio_backmerge, NULL); |
5f3ea37c | 1005 | WARN_ON(ret); |
38516ab5 | 1006 | ret = register_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge, NULL); |
5f3ea37c | 1007 | WARN_ON(ret); |
38516ab5 | 1008 | ret = register_trace_block_bio_queue(blk_add_trace_bio_queue, NULL); |
5f3ea37c | 1009 | WARN_ON(ret); |
38516ab5 | 1010 | ret = register_trace_block_getrq(blk_add_trace_getrq, NULL); |
5f3ea37c | 1011 | WARN_ON(ret); |
38516ab5 | 1012 | ret = register_trace_block_sleeprq(blk_add_trace_sleeprq, NULL); |
5f3ea37c | 1013 | WARN_ON(ret); |
38516ab5 | 1014 | ret = register_trace_block_plug(blk_add_trace_plug, NULL); |
5f3ea37c | 1015 | WARN_ON(ret); |
38516ab5 | 1016 | ret = register_trace_block_unplug_timer(blk_add_trace_unplug_timer, NULL); |
5f3ea37c | 1017 | WARN_ON(ret); |
38516ab5 | 1018 | ret = register_trace_block_unplug_io(blk_add_trace_unplug_io, NULL); |
5f3ea37c | 1019 | WARN_ON(ret); |
38516ab5 | 1020 | ret = register_trace_block_split(blk_add_trace_split, NULL); |
5f3ea37c | 1021 | WARN_ON(ret); |
38516ab5 | 1022 | ret = register_trace_block_remap(blk_add_trace_remap, NULL); |
5f3ea37c | 1023 | WARN_ON(ret); |
38516ab5 | 1024 | ret = register_trace_block_rq_remap(blk_add_trace_rq_remap, NULL); |
b0da3f0d | 1025 | WARN_ON(ret); |
5f3ea37c ACM |
1026 | } |
1027 | ||
1028 | static void blk_unregister_tracepoints(void) | |
1029 | { | |
38516ab5 SR |
1030 | unregister_trace_block_rq_remap(blk_add_trace_rq_remap, NULL); |
1031 | unregister_trace_block_remap(blk_add_trace_remap, NULL); | |
1032 | unregister_trace_block_split(blk_add_trace_split, NULL); | |
1033 | unregister_trace_block_unplug_io(blk_add_trace_unplug_io, NULL); | |
1034 | unregister_trace_block_unplug_timer(blk_add_trace_unplug_timer, NULL); | |
1035 | unregister_trace_block_plug(blk_add_trace_plug, NULL); | |
1036 | unregister_trace_block_sleeprq(blk_add_trace_sleeprq, NULL); | |
1037 | unregister_trace_block_getrq(blk_add_trace_getrq, NULL); | |
1038 | unregister_trace_block_bio_queue(blk_add_trace_bio_queue, NULL); | |
1039 | unregister_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge, NULL); | |
1040 | unregister_trace_block_bio_backmerge(blk_add_trace_bio_backmerge, NULL); | |
1041 | unregister_trace_block_bio_complete(blk_add_trace_bio_complete, NULL); | |
1042 | unregister_trace_block_bio_bounce(blk_add_trace_bio_bounce, NULL); | |
1043 | unregister_trace_block_rq_complete(blk_add_trace_rq_complete, NULL); | |
1044 | unregister_trace_block_rq_requeue(blk_add_trace_rq_requeue, NULL); | |
1045 | unregister_trace_block_rq_issue(blk_add_trace_rq_issue, NULL); | |
1046 | unregister_trace_block_rq_insert(blk_add_trace_rq_insert, NULL); | |
1047 | unregister_trace_block_rq_abort(blk_add_trace_rq_abort, NULL); | |
5f3ea37c ACM |
1048 | |
1049 | tracepoint_synchronize_unregister(); | |
1050 | } | |
c71a8961 ACM |
1051 | |
1052 | /* | |
1053 | * struct blk_io_tracer formatting routines | |
1054 | */ | |
1055 | ||
1056 | static void fill_rwbs(char *rwbs, const struct blk_io_trace *t) | |
1057 | { | |
157f9c00 | 1058 | int i = 0; |
65796348 | 1059 | int tc = t->action >> BLK_TC_SHIFT; |
157f9c00 | 1060 | |
18cea459 LZ |
1061 | if (t->action == BLK_TN_MESSAGE) { |
1062 | rwbs[i++] = 'N'; | |
1063 | goto out; | |
1064 | } | |
1065 | ||
65796348 | 1066 | if (tc & BLK_TC_DISCARD) |
157f9c00 | 1067 | rwbs[i++] = 'D'; |
65796348 | 1068 | else if (tc & BLK_TC_WRITE) |
157f9c00 ACM |
1069 | rwbs[i++] = 'W'; |
1070 | else if (t->bytes) | |
1071 | rwbs[i++] = 'R'; | |
1072 | else | |
1073 | rwbs[i++] = 'N'; | |
1074 | ||
65796348 | 1075 | if (tc & BLK_TC_AHEAD) |
157f9c00 | 1076 | rwbs[i++] = 'A'; |
65796348 | 1077 | if (tc & BLK_TC_BARRIER) |
157f9c00 | 1078 | rwbs[i++] = 'B'; |
65796348 | 1079 | if (tc & BLK_TC_SYNC) |
157f9c00 | 1080 | rwbs[i++] = 'S'; |
65796348 | 1081 | if (tc & BLK_TC_META) |
157f9c00 | 1082 | rwbs[i++] = 'M'; |
18cea459 | 1083 | out: |
157f9c00 | 1084 | rwbs[i] = '\0'; |
c71a8961 ACM |
1085 | } |
1086 | ||
1087 | static inline | |
1088 | const struct blk_io_trace *te_blk_io_trace(const struct trace_entry *ent) | |
1089 | { | |
1090 | return (const struct blk_io_trace *)ent; | |
1091 | } | |
1092 | ||
1093 | static inline const void *pdu_start(const struct trace_entry *ent) | |
1094 | { | |
1095 | return te_blk_io_trace(ent) + 1; | |
1096 | } | |
1097 | ||
66de7792 LZ |
1098 | static inline u32 t_action(const struct trace_entry *ent) |
1099 | { | |
1100 | return te_blk_io_trace(ent)->action; | |
1101 | } | |
1102 | ||
1103 | static inline u32 t_bytes(const struct trace_entry *ent) | |
1104 | { | |
1105 | return te_blk_io_trace(ent)->bytes; | |
1106 | } | |
1107 | ||
c71a8961 ACM |
1108 | static inline u32 t_sec(const struct trace_entry *ent) |
1109 | { | |
1110 | return te_blk_io_trace(ent)->bytes >> 9; | |
1111 | } | |
1112 | ||
1113 | static inline unsigned long long t_sector(const struct trace_entry *ent) | |
1114 | { | |
1115 | return te_blk_io_trace(ent)->sector; | |
1116 | } | |
1117 | ||
1118 | static inline __u16 t_error(const struct trace_entry *ent) | |
1119 | { | |
e0dc81be | 1120 | return te_blk_io_trace(ent)->error; |
c71a8961 ACM |
1121 | } |
1122 | ||
1123 | static __u64 get_pdu_int(const struct trace_entry *ent) | |
1124 | { | |
1125 | const __u64 *val = pdu_start(ent); | |
1126 | return be64_to_cpu(*val); | |
1127 | } | |
1128 | ||
1129 | static void get_pdu_remap(const struct trace_entry *ent, | |
1130 | struct blk_io_trace_remap *r) | |
1131 | { | |
1132 | const struct blk_io_trace_remap *__r = pdu_start(ent); | |
a42aaa3b | 1133 | __u64 sector_from = __r->sector_from; |
c71a8961 | 1134 | |
c71a8961 | 1135 | r->device_from = be32_to_cpu(__r->device_from); |
a42aaa3b AB |
1136 | r->device_to = be32_to_cpu(__r->device_to); |
1137 | r->sector_from = be64_to_cpu(sector_from); | |
c71a8961 ACM |
1138 | } |
1139 | ||
b6a4b0c3 LZ |
1140 | typedef int (blk_log_action_t) (struct trace_iterator *iter, const char *act); |
1141 | ||
1142 | static int blk_log_action_classic(struct trace_iterator *iter, const char *act) | |
c71a8961 ACM |
1143 | { |
1144 | char rwbs[6]; | |
35ac51bf LZ |
1145 | unsigned long long ts = iter->ts; |
1146 | unsigned long nsec_rem = do_div(ts, NSEC_PER_SEC); | |
c71a8961 | 1147 | unsigned secs = (unsigned long)ts; |
b6a4b0c3 | 1148 | const struct blk_io_trace *t = te_blk_io_trace(iter->ent); |
c71a8961 ACM |
1149 | |
1150 | fill_rwbs(rwbs, t); | |
1151 | ||
1152 | return trace_seq_printf(&iter->seq, | |
35ac51bf | 1153 | "%3d,%-3d %2d %5d.%09lu %5u %2s %3s ", |
c71a8961 | 1154 | MAJOR(t->device), MINOR(t->device), iter->cpu, |
b6a4b0c3 | 1155 | secs, nsec_rem, iter->ent->pid, act, rwbs); |
c71a8961 ACM |
1156 | } |
1157 | ||
b6a4b0c3 | 1158 | static int blk_log_action(struct trace_iterator *iter, const char *act) |
c71a8961 ACM |
1159 | { |
1160 | char rwbs[6]; | |
b6a4b0c3 LZ |
1161 | const struct blk_io_trace *t = te_blk_io_trace(iter->ent); |
1162 | ||
c71a8961 | 1163 | fill_rwbs(rwbs, t); |
b6a4b0c3 | 1164 | return trace_seq_printf(&iter->seq, "%3d,%-3d %2s %3s ", |
c71a8961 ACM |
1165 | MAJOR(t->device), MINOR(t->device), act, rwbs); |
1166 | } | |
1167 | ||
66de7792 LZ |
1168 | static int blk_log_dump_pdu(struct trace_seq *s, const struct trace_entry *ent) |
1169 | { | |
04986257 | 1170 | const unsigned char *pdu_buf; |
66de7792 LZ |
1171 | int pdu_len; |
1172 | int i, end, ret; | |
1173 | ||
1174 | pdu_buf = pdu_start(ent); | |
1175 | pdu_len = te_blk_io_trace(ent)->pdu_len; | |
1176 | ||
1177 | if (!pdu_len) | |
1178 | return 1; | |
1179 | ||
1180 | /* find the last zero that needs to be printed */ | |
1181 | for (end = pdu_len - 1; end >= 0; end--) | |
1182 | if (pdu_buf[end]) | |
1183 | break; | |
1184 | end++; | |
1185 | ||
1186 | if (!trace_seq_putc(s, '(')) | |
1187 | return 0; | |
1188 | ||
1189 | for (i = 0; i < pdu_len; i++) { | |
1190 | ||
1191 | ret = trace_seq_printf(s, "%s%02x", | |
1192 | i == 0 ? "" : " ", pdu_buf[i]); | |
1193 | if (!ret) | |
1194 | return ret; | |
1195 | ||
1196 | /* | |
1197 | * stop when the rest is just zeroes and indicate so | |
1198 | * with a ".." appended | |
1199 | */ | |
1200 | if (i == end && end != pdu_len - 1) | |
1201 | return trace_seq_puts(s, " ..) "); | |
1202 | } | |
1203 | ||
1204 | return trace_seq_puts(s, ") "); | |
1205 | } | |
1206 | ||
c71a8961 ACM |
1207 | static int blk_log_generic(struct trace_seq *s, const struct trace_entry *ent) |
1208 | { | |
4ca53085 SR |
1209 | char cmd[TASK_COMM_LEN]; |
1210 | ||
1211 | trace_find_cmdline(ent->pid, cmd); | |
c71a8961 | 1212 | |
66de7792 LZ |
1213 | if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { |
1214 | int ret; | |
1215 | ||
1216 | ret = trace_seq_printf(s, "%u ", t_bytes(ent)); | |
1217 | if (!ret) | |
1218 | return 0; | |
1219 | ret = blk_log_dump_pdu(s, ent); | |
1220 | if (!ret) | |
1221 | return 0; | |
1222 | return trace_seq_printf(s, "[%s]\n", cmd); | |
1223 | } else { | |
1224 | if (t_sec(ent)) | |
1225 | return trace_seq_printf(s, "%llu + %u [%s]\n", | |
1226 | t_sector(ent), t_sec(ent), cmd); | |
1227 | return trace_seq_printf(s, "[%s]\n", cmd); | |
1228 | } | |
c71a8961 ACM |
1229 | } |
1230 | ||
157f9c00 ACM |
1231 | static int blk_log_with_error(struct trace_seq *s, |
1232 | const struct trace_entry *ent) | |
c71a8961 | 1233 | { |
66de7792 LZ |
1234 | if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { |
1235 | int ret; | |
1236 | ||
1237 | ret = blk_log_dump_pdu(s, ent); | |
1238 | if (ret) | |
1239 | return trace_seq_printf(s, "[%d]\n", t_error(ent)); | |
1240 | return 0; | |
1241 | } else { | |
1242 | if (t_sec(ent)) | |
1243 | return trace_seq_printf(s, "%llu + %u [%d]\n", | |
1244 | t_sector(ent), | |
1245 | t_sec(ent), t_error(ent)); | |
1246 | return trace_seq_printf(s, "%llu [%d]\n", | |
1247 | t_sector(ent), t_error(ent)); | |
1248 | } | |
c71a8961 ACM |
1249 | } |
1250 | ||
1251 | static int blk_log_remap(struct trace_seq *s, const struct trace_entry *ent) | |
1252 | { | |
a42aaa3b | 1253 | struct blk_io_trace_remap r = { .device_from = 0, }; |
c71a8961 ACM |
1254 | |
1255 | get_pdu_remap(ent, &r); | |
1256 | return trace_seq_printf(s, "%llu + %u <- (%d,%d) %llu\n", | |
a42aaa3b AB |
1257 | t_sector(ent), t_sec(ent), |
1258 | MAJOR(r.device_from), MINOR(r.device_from), | |
1259 | (unsigned long long)r.sector_from); | |
c71a8961 ACM |
1260 | } |
1261 | ||
1262 | static int blk_log_plug(struct trace_seq *s, const struct trace_entry *ent) | |
1263 | { | |
4ca53085 SR |
1264 | char cmd[TASK_COMM_LEN]; |
1265 | ||
1266 | trace_find_cmdline(ent->pid, cmd); | |
1267 | ||
1268 | return trace_seq_printf(s, "[%s]\n", cmd); | |
c71a8961 ACM |
1269 | } |
1270 | ||
1271 | static int blk_log_unplug(struct trace_seq *s, const struct trace_entry *ent) | |
1272 | { | |
4ca53085 SR |
1273 | char cmd[TASK_COMM_LEN]; |
1274 | ||
1275 | trace_find_cmdline(ent->pid, cmd); | |
1276 | ||
1277 | return trace_seq_printf(s, "[%s] %llu\n", cmd, get_pdu_int(ent)); | |
c71a8961 ACM |
1278 | } |
1279 | ||
1280 | static int blk_log_split(struct trace_seq *s, const struct trace_entry *ent) | |
1281 | { | |
4ca53085 SR |
1282 | char cmd[TASK_COMM_LEN]; |
1283 | ||
1284 | trace_find_cmdline(ent->pid, cmd); | |
1285 | ||
c71a8961 | 1286 | return trace_seq_printf(s, "%llu / %llu [%s]\n", t_sector(ent), |
4ca53085 | 1287 | get_pdu_int(ent), cmd); |
c71a8961 ACM |
1288 | } |
1289 | ||
18cea459 LZ |
1290 | static int blk_log_msg(struct trace_seq *s, const struct trace_entry *ent) |
1291 | { | |
1292 | int ret; | |
1293 | const struct blk_io_trace *t = te_blk_io_trace(ent); | |
1294 | ||
1295 | ret = trace_seq_putmem(s, t + 1, t->pdu_len); | |
1296 | if (ret) | |
1297 | return trace_seq_putc(s, '\n'); | |
1298 | return ret; | |
1299 | } | |
1300 | ||
c71a8961 ACM |
1301 | /* |
1302 | * struct tracer operations | |
1303 | */ | |
1304 | ||
1305 | static void blk_tracer_print_header(struct seq_file *m) | |
1306 | { | |
1307 | if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) | |
1308 | return; | |
1309 | seq_puts(m, "# DEV CPU TIMESTAMP PID ACT FLG\n" | |
1310 | "# | | | | | |\n"); | |
1311 | } | |
1312 | ||
1313 | static void blk_tracer_start(struct trace_array *tr) | |
1314 | { | |
ad5dd549 | 1315 | blk_tracer_enabled = true; |
c71a8961 ACM |
1316 | } |
1317 | ||
1318 | static int blk_tracer_init(struct trace_array *tr) | |
1319 | { | |
1320 | blk_tr = tr; | |
1321 | blk_tracer_start(tr); | |
c71a8961 ACM |
1322 | return 0; |
1323 | } | |
1324 | ||
1325 | static void blk_tracer_stop(struct trace_array *tr) | |
1326 | { | |
ad5dd549 | 1327 | blk_tracer_enabled = false; |
c71a8961 ACM |
1328 | } |
1329 | ||
1330 | static void blk_tracer_reset(struct trace_array *tr) | |
1331 | { | |
c71a8961 ACM |
1332 | blk_tracer_stop(tr); |
1333 | } | |
1334 | ||
e4955c99 | 1335 | static const struct { |
c71a8961 | 1336 | const char *act[2]; |
ef18012b | 1337 | int (*print)(struct trace_seq *s, const struct trace_entry *ent); |
e4955c99 | 1338 | } what2act[] = { |
ef18012b | 1339 | [__BLK_TA_QUEUE] = {{ "Q", "queue" }, blk_log_generic }, |
c71a8961 ACM |
1340 | [__BLK_TA_BACKMERGE] = {{ "M", "backmerge" }, blk_log_generic }, |
1341 | [__BLK_TA_FRONTMERGE] = {{ "F", "frontmerge" }, blk_log_generic }, | |
1342 | [__BLK_TA_GETRQ] = {{ "G", "getrq" }, blk_log_generic }, | |
1343 | [__BLK_TA_SLEEPRQ] = {{ "S", "sleeprq" }, blk_log_generic }, | |
1344 | [__BLK_TA_REQUEUE] = {{ "R", "requeue" }, blk_log_with_error }, | |
1345 | [__BLK_TA_ISSUE] = {{ "D", "issue" }, blk_log_generic }, | |
1346 | [__BLK_TA_COMPLETE] = {{ "C", "complete" }, blk_log_with_error }, | |
1347 | [__BLK_TA_PLUG] = {{ "P", "plug" }, blk_log_plug }, | |
1348 | [__BLK_TA_UNPLUG_IO] = {{ "U", "unplug_io" }, blk_log_unplug }, | |
1349 | [__BLK_TA_UNPLUG_TIMER] = {{ "UT", "unplug_timer" }, blk_log_unplug }, | |
1350 | [__BLK_TA_INSERT] = {{ "I", "insert" }, blk_log_generic }, | |
1351 | [__BLK_TA_SPLIT] = {{ "X", "split" }, blk_log_split }, | |
1352 | [__BLK_TA_BOUNCE] = {{ "B", "bounce" }, blk_log_generic }, | |
1353 | [__BLK_TA_REMAP] = {{ "A", "remap" }, blk_log_remap }, | |
1354 | }; | |
1355 | ||
b6a4b0c3 LZ |
1356 | static enum print_line_t print_one_line(struct trace_iterator *iter, |
1357 | bool classic) | |
c71a8961 | 1358 | { |
2c9b238e | 1359 | struct trace_seq *s = &iter->seq; |
b6a4b0c3 LZ |
1360 | const struct blk_io_trace *t; |
1361 | u16 what; | |
c71a8961 | 1362 | int ret; |
b6a4b0c3 LZ |
1363 | bool long_act; |
1364 | blk_log_action_t *log_action; | |
c71a8961 | 1365 | |
b6a4b0c3 LZ |
1366 | t = te_blk_io_trace(iter->ent); |
1367 | what = t->action & ((1 << BLK_TC_SHIFT) - 1); | |
1368 | long_act = !!(trace_flags & TRACE_ITER_VERBOSE); | |
1369 | log_action = classic ? &blk_log_action_classic : &blk_log_action; | |
08a06b83 | 1370 | |
18cea459 LZ |
1371 | if (t->action == BLK_TN_MESSAGE) { |
1372 | ret = log_action(iter, long_act ? "message" : "m"); | |
1373 | if (ret) | |
1374 | ret = blk_log_msg(s, iter->ent); | |
1375 | goto out; | |
1376 | } | |
1377 | ||
eb08f8eb | 1378 | if (unlikely(what == 0 || what >= ARRAY_SIZE(what2act))) |
b78825d6 | 1379 | ret = trace_seq_printf(s, "Unknown action %x\n", what); |
c71a8961 | 1380 | else { |
b6a4b0c3 | 1381 | ret = log_action(iter, what2act[what].act[long_act]); |
c71a8961 | 1382 | if (ret) |
2c9b238e | 1383 | ret = what2act[what].print(s, iter->ent); |
c71a8961 | 1384 | } |
18cea459 | 1385 | out: |
c71a8961 ACM |
1386 | return ret ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; |
1387 | } | |
1388 | ||
b6a4b0c3 | 1389 | static enum print_line_t blk_trace_event_print(struct trace_iterator *iter, |
a9a57763 | 1390 | int flags, struct trace_event *event) |
b6a4b0c3 | 1391 | { |
b6a4b0c3 LZ |
1392 | return print_one_line(iter, false); |
1393 | } | |
1394 | ||
08a06b83 ACM |
1395 | static int blk_trace_synthesize_old_trace(struct trace_iterator *iter) |
1396 | { | |
1397 | struct trace_seq *s = &iter->seq; | |
1398 | struct blk_io_trace *t = (struct blk_io_trace *)iter->ent; | |
1399 | const int offset = offsetof(struct blk_io_trace, sector); | |
1400 | struct blk_io_trace old = { | |
1401 | .magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION, | |
6c051ce0 | 1402 | .time = iter->ts, |
08a06b83 ACM |
1403 | }; |
1404 | ||
1405 | if (!trace_seq_putmem(s, &old, offset)) | |
1406 | return 0; | |
1407 | return trace_seq_putmem(s, &t->sector, | |
1408 | sizeof(old) - offset + t->pdu_len); | |
1409 | } | |
1410 | ||
ae7462b4 | 1411 | static enum print_line_t |
a9a57763 SR |
1412 | blk_trace_event_print_binary(struct trace_iterator *iter, int flags, |
1413 | struct trace_event *event) | |
08a06b83 ACM |
1414 | { |
1415 | return blk_trace_synthesize_old_trace(iter) ? | |
1416 | TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; | |
1417 | } | |
1418 | ||
c71a8961 ACM |
1419 | static enum print_line_t blk_tracer_print_line(struct trace_iterator *iter) |
1420 | { | |
c71a8961 ACM |
1421 | if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) |
1422 | return TRACE_TYPE_UNHANDLED; | |
1423 | ||
b6a4b0c3 | 1424 | return print_one_line(iter, true); |
c71a8961 ACM |
1425 | } |
1426 | ||
f3948f88 LZ |
1427 | static int blk_tracer_set_flag(u32 old_flags, u32 bit, int set) |
1428 | { | |
1429 | /* don't output context-info for blk_classic output */ | |
1430 | if (bit == TRACE_BLK_OPT_CLASSIC) { | |
1431 | if (set) | |
1432 | trace_flags &= ~TRACE_ITER_CONTEXT_INFO; | |
1433 | else | |
1434 | trace_flags |= TRACE_ITER_CONTEXT_INFO; | |
1435 | } | |
1436 | return 0; | |
1437 | } | |
1438 | ||
c71a8961 ACM |
1439 | static struct tracer blk_tracer __read_mostly = { |
1440 | .name = "blk", | |
1441 | .init = blk_tracer_init, | |
1442 | .reset = blk_tracer_reset, | |
1443 | .start = blk_tracer_start, | |
1444 | .stop = blk_tracer_stop, | |
1445 | .print_header = blk_tracer_print_header, | |
1446 | .print_line = blk_tracer_print_line, | |
1447 | .flags = &blk_tracer_flags, | |
f3948f88 | 1448 | .set_flag = blk_tracer_set_flag, |
c71a8961 ACM |
1449 | }; |
1450 | ||
a9a57763 | 1451 | static struct trace_event_functions trace_blk_event_funcs = { |
c71a8961 | 1452 | .trace = blk_trace_event_print, |
08a06b83 | 1453 | .binary = blk_trace_event_print_binary, |
c71a8961 ACM |
1454 | }; |
1455 | ||
a9a57763 SR |
1456 | static struct trace_event trace_blk_event = { |
1457 | .type = TRACE_BLK, | |
1458 | .funcs = &trace_blk_event_funcs, | |
1459 | }; | |
1460 | ||
c71a8961 ACM |
1461 | static int __init init_blk_tracer(void) |
1462 | { | |
1463 | if (!register_ftrace_event(&trace_blk_event)) { | |
1464 | pr_warning("Warning: could not register block events\n"); | |
1465 | return 1; | |
1466 | } | |
1467 | ||
1468 | if (register_tracer(&blk_tracer) != 0) { | |
1469 | pr_warning("Warning: could not register the block tracer\n"); | |
1470 | unregister_ftrace_event(&trace_blk_event); | |
1471 | return 1; | |
1472 | } | |
1473 | ||
1474 | return 0; | |
1475 | } | |
1476 | ||
1477 | device_initcall(init_blk_tracer); | |
1478 | ||
1479 | static int blk_trace_remove_queue(struct request_queue *q) | |
1480 | { | |
1481 | struct blk_trace *bt; | |
1482 | ||
1483 | bt = xchg(&q->blk_trace, NULL); | |
1484 | if (bt == NULL) | |
1485 | return -EINVAL; | |
1486 | ||
17ba97e3 LZ |
1487 | if (atomic_dec_and_test(&blk_probes_ref)) |
1488 | blk_unregister_tracepoints(); | |
1489 | ||
ad5dd549 | 1490 | blk_trace_free(bt); |
c71a8961 ACM |
1491 | return 0; |
1492 | } | |
1493 | ||
1494 | /* | |
1495 | * Setup everything required to start tracing | |
1496 | */ | |
9908c309 LZ |
1497 | static int blk_trace_setup_queue(struct request_queue *q, |
1498 | struct block_device *bdev) | |
c71a8961 ACM |
1499 | { |
1500 | struct blk_trace *old_bt, *bt = NULL; | |
18cea459 | 1501 | int ret = -ENOMEM; |
c71a8961 | 1502 | |
c71a8961 ACM |
1503 | bt = kzalloc(sizeof(*bt), GFP_KERNEL); |
1504 | if (!bt) | |
15152e44 | 1505 | return -ENOMEM; |
c71a8961 | 1506 | |
18cea459 LZ |
1507 | bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); |
1508 | if (!bt->msg_data) | |
1509 | goto free_bt; | |
1510 | ||
9908c309 | 1511 | bt->dev = bdev->bd_dev; |
c71a8961 | 1512 | bt->act_mask = (u16)-1; |
9908c309 LZ |
1513 | |
1514 | blk_trace_setup_lba(bt, bdev); | |
c71a8961 ACM |
1515 | |
1516 | old_bt = xchg(&q->blk_trace, bt); | |
1517 | if (old_bt != NULL) { | |
1518 | (void)xchg(&q->blk_trace, old_bt); | |
18cea459 LZ |
1519 | ret = -EBUSY; |
1520 | goto free_bt; | |
c71a8961 | 1521 | } |
15152e44 | 1522 | |
17ba97e3 LZ |
1523 | if (atomic_inc_return(&blk_probes_ref) == 1) |
1524 | blk_register_tracepoints(); | |
c71a8961 | 1525 | return 0; |
18cea459 LZ |
1526 | |
1527 | free_bt: | |
1528 | blk_trace_free(bt); | |
1529 | return ret; | |
c71a8961 ACM |
1530 | } |
1531 | ||
1532 | /* | |
1533 | * sysfs interface to enable and configure tracing | |
1534 | */ | |
1535 | ||
c71a8961 ACM |
1536 | static ssize_t sysfs_blk_trace_attr_show(struct device *dev, |
1537 | struct device_attribute *attr, | |
1538 | char *buf); | |
1539 | static ssize_t sysfs_blk_trace_attr_store(struct device *dev, | |
1540 | struct device_attribute *attr, | |
1541 | const char *buf, size_t count); | |
1542 | #define BLK_TRACE_DEVICE_ATTR(_name) \ | |
1543 | DEVICE_ATTR(_name, S_IRUGO | S_IWUSR, \ | |
1544 | sysfs_blk_trace_attr_show, \ | |
1545 | sysfs_blk_trace_attr_store) | |
1546 | ||
cd649b8b | 1547 | static BLK_TRACE_DEVICE_ATTR(enable); |
c71a8961 ACM |
1548 | static BLK_TRACE_DEVICE_ATTR(act_mask); |
1549 | static BLK_TRACE_DEVICE_ATTR(pid); | |
1550 | static BLK_TRACE_DEVICE_ATTR(start_lba); | |
1551 | static BLK_TRACE_DEVICE_ATTR(end_lba); | |
1552 | ||
1553 | static struct attribute *blk_trace_attrs[] = { | |
1554 | &dev_attr_enable.attr, | |
1555 | &dev_attr_act_mask.attr, | |
1556 | &dev_attr_pid.attr, | |
1557 | &dev_attr_start_lba.attr, | |
1558 | &dev_attr_end_lba.attr, | |
1559 | NULL | |
1560 | }; | |
1561 | ||
1562 | struct attribute_group blk_trace_attr_group = { | |
1563 | .name = "trace", | |
1564 | .attrs = blk_trace_attrs, | |
1565 | }; | |
1566 | ||
09341997 LZ |
1567 | static const struct { |
1568 | int mask; | |
1569 | const char *str; | |
1570 | } mask_maps[] = { | |
1571 | { BLK_TC_READ, "read" }, | |
1572 | { BLK_TC_WRITE, "write" }, | |
1573 | { BLK_TC_BARRIER, "barrier" }, | |
1574 | { BLK_TC_SYNC, "sync" }, | |
1575 | { BLK_TC_QUEUE, "queue" }, | |
1576 | { BLK_TC_REQUEUE, "requeue" }, | |
1577 | { BLK_TC_ISSUE, "issue" }, | |
1578 | { BLK_TC_COMPLETE, "complete" }, | |
1579 | { BLK_TC_FS, "fs" }, | |
1580 | { BLK_TC_PC, "pc" }, | |
1581 | { BLK_TC_AHEAD, "ahead" }, | |
1582 | { BLK_TC_META, "meta" }, | |
1583 | { BLK_TC_DISCARD, "discard" }, | |
1584 | { BLK_TC_DRV_DATA, "drv_data" }, | |
1585 | }; | |
1586 | ||
1587 | static int blk_trace_str2mask(const char *str) | |
c71a8961 | 1588 | { |
09341997 | 1589 | int i; |
c71a8961 | 1590 | int mask = 0; |
9eb85125 | 1591 | char *buf, *s, *token; |
c71a8961 | 1592 | |
9eb85125 LZ |
1593 | buf = kstrdup(str, GFP_KERNEL); |
1594 | if (buf == NULL) | |
c71a8961 | 1595 | return -ENOMEM; |
9eb85125 | 1596 | s = strstrip(buf); |
c71a8961 ACM |
1597 | |
1598 | while (1) { | |
09341997 LZ |
1599 | token = strsep(&s, ","); |
1600 | if (token == NULL) | |
c71a8961 ACM |
1601 | break; |
1602 | ||
09341997 LZ |
1603 | if (*token == '\0') |
1604 | continue; | |
1605 | ||
1606 | for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { | |
1607 | if (strcasecmp(token, mask_maps[i].str) == 0) { | |
1608 | mask |= mask_maps[i].mask; | |
1609 | break; | |
1610 | } | |
1611 | } | |
1612 | if (i == ARRAY_SIZE(mask_maps)) { | |
1613 | mask = -EINVAL; | |
1614 | break; | |
1615 | } | |
c71a8961 | 1616 | } |
9eb85125 | 1617 | kfree(buf); |
c71a8961 ACM |
1618 | |
1619 | return mask; | |
1620 | } | |
1621 | ||
09341997 LZ |
1622 | static ssize_t blk_trace_mask2str(char *buf, int mask) |
1623 | { | |
1624 | int i; | |
1625 | char *p = buf; | |
1626 | ||
1627 | for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { | |
1628 | if (mask & mask_maps[i].mask) { | |
1629 | p += sprintf(p, "%s%s", | |
1630 | (p == buf) ? "" : ",", mask_maps[i].str); | |
1631 | } | |
1632 | } | |
1633 | *p++ = '\n'; | |
1634 | ||
1635 | return p - buf; | |
1636 | } | |
1637 | ||
b125130b LZ |
1638 | static struct request_queue *blk_trace_get_queue(struct block_device *bdev) |
1639 | { | |
1640 | if (bdev->bd_disk == NULL) | |
1641 | return NULL; | |
1642 | ||
1643 | return bdev_get_queue(bdev); | |
1644 | } | |
1645 | ||
c71a8961 ACM |
1646 | static ssize_t sysfs_blk_trace_attr_show(struct device *dev, |
1647 | struct device_attribute *attr, | |
1648 | char *buf) | |
1649 | { | |
1650 | struct hd_struct *p = dev_to_part(dev); | |
1651 | struct request_queue *q; | |
1652 | struct block_device *bdev; | |
1653 | ssize_t ret = -ENXIO; | |
1654 | ||
1655 | lock_kernel(); | |
1656 | bdev = bdget(part_devt(p)); | |
1657 | if (bdev == NULL) | |
1658 | goto out_unlock_kernel; | |
1659 | ||
b125130b | 1660 | q = blk_trace_get_queue(bdev); |
c71a8961 ACM |
1661 | if (q == NULL) |
1662 | goto out_bdput; | |
b125130b | 1663 | |
c71a8961 | 1664 | mutex_lock(&bdev->bd_mutex); |
cd649b8b LZ |
1665 | |
1666 | if (attr == &dev_attr_enable) { | |
1667 | ret = sprintf(buf, "%u\n", !!q->blk_trace); | |
1668 | goto out_unlock_bdev; | |
1669 | } | |
1670 | ||
c71a8961 ACM |
1671 | if (q->blk_trace == NULL) |
1672 | ret = sprintf(buf, "disabled\n"); | |
1673 | else if (attr == &dev_attr_act_mask) | |
09341997 | 1674 | ret = blk_trace_mask2str(buf, q->blk_trace->act_mask); |
c71a8961 ACM |
1675 | else if (attr == &dev_attr_pid) |
1676 | ret = sprintf(buf, "%u\n", q->blk_trace->pid); | |
1677 | else if (attr == &dev_attr_start_lba) | |
1678 | ret = sprintf(buf, "%llu\n", q->blk_trace->start_lba); | |
1679 | else if (attr == &dev_attr_end_lba) | |
1680 | ret = sprintf(buf, "%llu\n", q->blk_trace->end_lba); | |
cd649b8b LZ |
1681 | |
1682 | out_unlock_bdev: | |
c71a8961 ACM |
1683 | mutex_unlock(&bdev->bd_mutex); |
1684 | out_bdput: | |
1685 | bdput(bdev); | |
1686 | out_unlock_kernel: | |
1687 | unlock_kernel(); | |
1688 | return ret; | |
1689 | } | |
1690 | ||
1691 | static ssize_t sysfs_blk_trace_attr_store(struct device *dev, | |
1692 | struct device_attribute *attr, | |
1693 | const char *buf, size_t count) | |
1694 | { | |
1695 | struct block_device *bdev; | |
1696 | struct request_queue *q; | |
1697 | struct hd_struct *p; | |
1698 | u64 value; | |
09341997 | 1699 | ssize_t ret = -EINVAL; |
c71a8961 ACM |
1700 | |
1701 | if (count == 0) | |
1702 | goto out; | |
1703 | ||
1704 | if (attr == &dev_attr_act_mask) { | |
1705 | if (sscanf(buf, "%llx", &value) != 1) { | |
1706 | /* Assume it is a list of trace category names */ | |
09341997 LZ |
1707 | ret = blk_trace_str2mask(buf); |
1708 | if (ret < 0) | |
c71a8961 | 1709 | goto out; |
09341997 | 1710 | value = ret; |
c71a8961 ACM |
1711 | } |
1712 | } else if (sscanf(buf, "%llu", &value) != 1) | |
1713 | goto out; | |
1714 | ||
09341997 LZ |
1715 | ret = -ENXIO; |
1716 | ||
c71a8961 ACM |
1717 | lock_kernel(); |
1718 | p = dev_to_part(dev); | |
1719 | bdev = bdget(part_devt(p)); | |
1720 | if (bdev == NULL) | |
1721 | goto out_unlock_kernel; | |
1722 | ||
b125130b | 1723 | q = blk_trace_get_queue(bdev); |
c71a8961 ACM |
1724 | if (q == NULL) |
1725 | goto out_bdput; | |
1726 | ||
1727 | mutex_lock(&bdev->bd_mutex); | |
cd649b8b LZ |
1728 | |
1729 | if (attr == &dev_attr_enable) { | |
1730 | if (value) | |
9908c309 | 1731 | ret = blk_trace_setup_queue(q, bdev); |
cd649b8b LZ |
1732 | else |
1733 | ret = blk_trace_remove_queue(q); | |
1734 | goto out_unlock_bdev; | |
1735 | } | |
1736 | ||
c71a8961 ACM |
1737 | ret = 0; |
1738 | if (q->blk_trace == NULL) | |
9908c309 | 1739 | ret = blk_trace_setup_queue(q, bdev); |
c71a8961 ACM |
1740 | |
1741 | if (ret == 0) { | |
1742 | if (attr == &dev_attr_act_mask) | |
1743 | q->blk_trace->act_mask = value; | |
1744 | else if (attr == &dev_attr_pid) | |
1745 | q->blk_trace->pid = value; | |
1746 | else if (attr == &dev_attr_start_lba) | |
1747 | q->blk_trace->start_lba = value; | |
1748 | else if (attr == &dev_attr_end_lba) | |
1749 | q->blk_trace->end_lba = value; | |
c71a8961 | 1750 | } |
cd649b8b LZ |
1751 | |
1752 | out_unlock_bdev: | |
c71a8961 ACM |
1753 | mutex_unlock(&bdev->bd_mutex); |
1754 | out_bdput: | |
1755 | bdput(bdev); | |
1756 | out_unlock_kernel: | |
1757 | unlock_kernel(); | |
1758 | out: | |
cd649b8b | 1759 | return ret ? ret : count; |
c71a8961 | 1760 | } |
cd649b8b | 1761 | |
1d54ad6d LZ |
1762 | int blk_trace_init_sysfs(struct device *dev) |
1763 | { | |
1764 | return sysfs_create_group(&dev->kobj, &blk_trace_attr_group); | |
1765 | } | |
1766 | ||
48c0d4d4 ZK |
1767 | void blk_trace_remove_sysfs(struct device *dev) |
1768 | { | |
1769 | sysfs_remove_group(&dev->kobj, &blk_trace_attr_group); | |
1770 | } | |
1771 | ||
55782138 LZ |
1772 | #endif /* CONFIG_BLK_DEV_IO_TRACE */ |
1773 | ||
1774 | #ifdef CONFIG_EVENT_TRACING | |
1775 | ||
1776 | void blk_dump_cmd(char *buf, struct request *rq) | |
1777 | { | |
1778 | int i, end; | |
1779 | int len = rq->cmd_len; | |
1780 | unsigned char *cmd = rq->cmd; | |
1781 | ||
33659ebb | 1782 | if (rq->cmd_type != REQ_TYPE_BLOCK_PC) { |
55782138 LZ |
1783 | buf[0] = '\0'; |
1784 | return; | |
1785 | } | |
1786 | ||
1787 | for (end = len - 1; end >= 0; end--) | |
1788 | if (cmd[end]) | |
1789 | break; | |
1790 | end++; | |
1791 | ||
1792 | for (i = 0; i < len; i++) { | |
1793 | buf += sprintf(buf, "%s%02x", i == 0 ? "" : " ", cmd[i]); | |
1794 | if (i == end && end != len - 1) { | |
1795 | sprintf(buf, " .."); | |
1796 | break; | |
1797 | } | |
1798 | } | |
1799 | } | |
1800 | ||
1801 | void blk_fill_rwbs(char *rwbs, u32 rw, int bytes) | |
1802 | { | |
1803 | int i = 0; | |
1804 | ||
1805 | if (rw & WRITE) | |
1806 | rwbs[i++] = 'W'; | |
7b6d91da | 1807 | else if (rw & REQ_DISCARD) |
55782138 LZ |
1808 | rwbs[i++] = 'D'; |
1809 | else if (bytes) | |
1810 | rwbs[i++] = 'R'; | |
1811 | else | |
1812 | rwbs[i++] = 'N'; | |
1813 | ||
7b6d91da | 1814 | if (rw & REQ_RAHEAD) |
55782138 | 1815 | rwbs[i++] = 'A'; |
7b6d91da | 1816 | if (rw & REQ_HARDBARRIER) |
55782138 | 1817 | rwbs[i++] = 'B'; |
7b6d91da | 1818 | if (rw & REQ_SYNC) |
55782138 | 1819 | rwbs[i++] = 'S'; |
7b6d91da | 1820 | if (rw & REQ_META) |
55782138 | 1821 | rwbs[i++] = 'M'; |
8d57a98c AH |
1822 | if (rw & REQ_SECURE) |
1823 | rwbs[i++] = 'E'; | |
55782138 LZ |
1824 | |
1825 | rwbs[i] = '\0'; | |
1826 | } | |
1827 | ||
1828 | void blk_fill_rwbs_rq(char *rwbs, struct request *rq) | |
1829 | { | |
1830 | int rw = rq->cmd_flags & 0x03; | |
1831 | int bytes; | |
1832 | ||
33659ebb | 1833 | if (rq->cmd_flags & REQ_DISCARD) |
7b6d91da | 1834 | rw |= REQ_DISCARD; |
55782138 | 1835 | |
8d57a98c AH |
1836 | if (rq->cmd_flags & REQ_SECURE) |
1837 | rw |= REQ_SECURE; | |
1838 | ||
c9059598 | 1839 | bytes = blk_rq_bytes(rq); |
55782138 LZ |
1840 | |
1841 | blk_fill_rwbs(rwbs, rw, bytes); | |
1842 | } | |
1843 | ||
1844 | #endif /* CONFIG_EVENT_TRACING */ | |
1845 |