Commit | Line | Data |
---|---|---|
2056a782 | 1 | /* |
0fe23479 | 2 | * Copyright (C) 2006 Jens Axboe <axboe@kernel.dk> |
2056a782 JA |
3 | * |
4 | * This program is free software; you can redistribute it and/or modify | |
5 | * it under the terms of the GNU General Public License version 2 as | |
6 | * published by the Free Software Foundation. | |
7 | * | |
8 | * This program is distributed in the hope that it will be useful, | |
9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
11 | * GNU General Public License for more details. | |
12 | * | |
13 | * You should have received a copy of the GNU General Public License | |
14 | * along with this program; if not, write to the Free Software | |
15 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
16 | * | |
17 | */ | |
2056a782 JA |
18 | #include <linux/kernel.h> |
19 | #include <linux/blkdev.h> | |
20 | #include <linux/blktrace_api.h> | |
21 | #include <linux/percpu.h> | |
22 | #include <linux/init.h> | |
23 | #include <linux/mutex.h> | |
24 | #include <linux/debugfs.h> | |
405f5571 | 25 | #include <linux/smp_lock.h> |
be1c6341 | 26 | #include <linux/time.h> |
939b3669 | 27 | #include <linux/uaccess.h> |
55782138 LZ |
28 | |
29 | #include <trace/events/block.h> | |
30 | ||
2db270a8 | 31 | #include "trace_output.h" |
2056a782 | 32 | |
55782138 LZ |
33 | #ifdef CONFIG_BLK_DEV_IO_TRACE |
34 | ||
2056a782 JA |
35 | static unsigned int blktrace_seq __read_mostly = 1; |
36 | ||
c71a8961 | 37 | static struct trace_array *blk_tr; |
5006ea73 | 38 | static bool blk_tracer_enabled __read_mostly; |
c71a8961 ACM |
39 | |
40 | /* Select an alternative, minimalistic output than the original one */ | |
ef18012b | 41 | #define TRACE_BLK_OPT_CLASSIC 0x1 |
c71a8961 ACM |
42 | |
43 | static struct tracer_opt blk_tracer_opts[] = { | |
44 | /* Default disable the minimalistic output */ | |
157f9c00 | 45 | { TRACER_OPT(blk_classic, TRACE_BLK_OPT_CLASSIC) }, |
c71a8961 ACM |
46 | { } |
47 | }; | |
48 | ||
49 | static struct tracer_flags blk_tracer_flags = { | |
50 | .val = 0, | |
51 | .opts = blk_tracer_opts, | |
52 | }; | |
53 | ||
5f3ea37c | 54 | /* Global reference count of probes */ |
5f3ea37c ACM |
55 | static atomic_t blk_probes_ref = ATOMIC_INIT(0); |
56 | ||
3c289ba7 | 57 | static void blk_register_tracepoints(void); |
5f3ea37c ACM |
58 | static void blk_unregister_tracepoints(void); |
59 | ||
be1c6341 OK |
60 | /* |
61 | * Send out a notify message. | |
62 | */ | |
a863055b JA |
63 | static void trace_note(struct blk_trace *bt, pid_t pid, int action, |
64 | const void *data, size_t len) | |
be1c6341 OK |
65 | { |
66 | struct blk_io_trace *t; | |
18cea459 | 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 | |
35ba8f70 | 171 | /* The ilog2() calls fall out because they're constant */ |
939b3669 ACM |
172 | #define MASK_TC_BIT(rw, __name) ((rw & (1 << BIO_RW_ ## __name)) << \ |
173 | (ilog2(BLK_TC_ ## __name) + BLK_TC_SHIFT - BIO_RW_ ## __name)) | |
2056a782 JA |
174 | |
175 | /* | |
176 | * The worker for the various blk_add_trace*() types. Fills out a | |
177 | * blk_io_trace structure and places it in a per-cpu subbuffer. | |
178 | */ | |
5f3ea37c | 179 | static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, |
2056a782 JA |
180 | int rw, u32 what, int error, int pdu_len, void *pdu_data) |
181 | { | |
182 | struct task_struct *tsk = current; | |
c71a8961 | 183 | struct ring_buffer_event *event = NULL; |
e77405ad | 184 | struct ring_buffer *buffer = NULL; |
2056a782 | 185 | struct blk_io_trace *t; |
0a987751 | 186 | unsigned long flags = 0; |
2056a782 JA |
187 | unsigned long *sequence; |
188 | pid_t pid; | |
c71a8961 | 189 | int cpu, pc = 0; |
18cea459 | 190 | bool blk_tracer = blk_tracer_enabled; |
2056a782 | 191 | |
18cea459 | 192 | if (unlikely(bt->trace_state != Blktrace_running && !blk_tracer)) |
2056a782 JA |
193 | return; |
194 | ||
195 | what |= ddir_act[rw & WRITE]; | |
35ba8f70 | 196 | what |= MASK_TC_BIT(rw, BARRIER); |
93dbb393 | 197 | what |= MASK_TC_BIT(rw, SYNCIO); |
35ba8f70 DW |
198 | what |= MASK_TC_BIT(rw, AHEAD); |
199 | what |= MASK_TC_BIT(rw, META); | |
200 | what |= MASK_TC_BIT(rw, DISCARD); | |
2056a782 JA |
201 | |
202 | pid = tsk->pid; | |
d0deef5b | 203 | if (act_log_check(bt, what, sector, pid)) |
2056a782 | 204 | return; |
c71a8961 ACM |
205 | cpu = raw_smp_processor_id(); |
206 | ||
18cea459 | 207 | if (blk_tracer) { |
c71a8961 ACM |
208 | tracing_record_cmdline(current); |
209 | ||
e77405ad | 210 | buffer = blk_tr->buffer; |
51a763dd | 211 | pc = preempt_count(); |
e77405ad | 212 | event = trace_buffer_lock_reserve(buffer, TRACE_BLK, |
51a763dd ACM |
213 | sizeof(*t) + pdu_len, |
214 | 0, pc); | |
c71a8961 ACM |
215 | if (!event) |
216 | return; | |
51a763dd | 217 | t = ring_buffer_event_data(event); |
c71a8961 ACM |
218 | goto record_it; |
219 | } | |
2056a782 JA |
220 | |
221 | /* | |
222 | * A word about the locking here - we disable interrupts to reserve | |
223 | * some space in the relay per-cpu buffer, to prevent an irq | |
14a73f54 | 224 | * from coming in and stepping on our toes. |
2056a782 JA |
225 | */ |
226 | local_irq_save(flags); | |
227 | ||
228 | if (unlikely(tsk->btrace_seq != blktrace_seq)) | |
229 | trace_note_tsk(bt, tsk); | |
230 | ||
231 | t = relay_reserve(bt->rchan, sizeof(*t) + pdu_len); | |
232 | if (t) { | |
2056a782 JA |
233 | sequence = per_cpu_ptr(bt->sequence, cpu); |
234 | ||
235 | t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; | |
236 | t->sequence = ++(*sequence); | |
2997c8c4 | 237 | t->time = ktime_to_ns(ktime_get()); |
c71a8961 | 238 | record_it: |
08a06b83 | 239 | /* |
939b3669 ACM |
240 | * These two are not needed in ftrace as they are in the |
241 | * generic trace_entry, filled by tracing_generic_entry_update, | |
242 | * but for the trace_event->bin() synthesizer benefit we do it | |
243 | * here too. | |
244 | */ | |
245 | t->cpu = cpu; | |
246 | t->pid = pid; | |
08a06b83 | 247 | |
2056a782 JA |
248 | t->sector = sector; |
249 | t->bytes = bytes; | |
250 | t->action = what; | |
2056a782 | 251 | t->device = bt->dev; |
2056a782 JA |
252 | t->error = error; |
253 | t->pdu_len = pdu_len; | |
254 | ||
255 | if (pdu_len) | |
256 | memcpy((void *) t + sizeof(*t), pdu_data, pdu_len); | |
c71a8961 | 257 | |
18cea459 | 258 | if (blk_tracer) { |
e77405ad | 259 | trace_buffer_unlock_commit(buffer, event, 0, pc); |
c71a8961 ACM |
260 | return; |
261 | } | |
2056a782 JA |
262 | } |
263 | ||
264 | local_irq_restore(flags); | |
265 | } | |
266 | ||
2056a782 | 267 | static struct dentry *blk_tree_root; |
11a57153 | 268 | static DEFINE_MUTEX(blk_tree_mutex); |
2056a782 | 269 | |
ad5dd549 | 270 | static void blk_trace_free(struct blk_trace *bt) |
2056a782 | 271 | { |
02c62304 | 272 | debugfs_remove(bt->msg_file); |
2056a782 | 273 | debugfs_remove(bt->dropped_file); |
f48fc4d3 | 274 | relay_close(bt->rchan); |
39cbb602 | 275 | debugfs_remove(bt->dir); |
2056a782 | 276 | free_percpu(bt->sequence); |
64565911 | 277 | free_percpu(bt->msg_data); |
2056a782 | 278 | kfree(bt); |
ad5dd549 LZ |
279 | } |
280 | ||
281 | static void blk_trace_cleanup(struct blk_trace *bt) | |
282 | { | |
283 | blk_trace_free(bt); | |
5f3ea37c ACM |
284 | if (atomic_dec_and_test(&blk_probes_ref)) |
285 | blk_unregister_tracepoints(); | |
2056a782 JA |
286 | } |
287 | ||
6da127ad | 288 | int blk_trace_remove(struct request_queue *q) |
2056a782 JA |
289 | { |
290 | struct blk_trace *bt; | |
291 | ||
292 | bt = xchg(&q->blk_trace, NULL); | |
293 | if (!bt) | |
294 | return -EINVAL; | |
295 | ||
55547204 | 296 | if (bt->trace_state != Blktrace_running) |
2056a782 JA |
297 | blk_trace_cleanup(bt); |
298 | ||
299 | return 0; | |
300 | } | |
6da127ad | 301 | EXPORT_SYMBOL_GPL(blk_trace_remove); |
2056a782 JA |
302 | |
303 | static int blk_dropped_open(struct inode *inode, struct file *filp) | |
304 | { | |
8e18e294 | 305 | filp->private_data = inode->i_private; |
2056a782 JA |
306 | |
307 | return 0; | |
308 | } | |
309 | ||
310 | static ssize_t blk_dropped_read(struct file *filp, char __user *buffer, | |
311 | size_t count, loff_t *ppos) | |
312 | { | |
313 | struct blk_trace *bt = filp->private_data; | |
314 | char buf[16]; | |
315 | ||
316 | snprintf(buf, sizeof(buf), "%u\n", atomic_read(&bt->dropped)); | |
317 | ||
318 | return simple_read_from_buffer(buffer, count, ppos, buf, strlen(buf)); | |
319 | } | |
320 | ||
2b8693c0 | 321 | static const struct file_operations blk_dropped_fops = { |
2056a782 JA |
322 | .owner = THIS_MODULE, |
323 | .open = blk_dropped_open, | |
324 | .read = blk_dropped_read, | |
325 | }; | |
326 | ||
02c62304 AB |
327 | static int blk_msg_open(struct inode *inode, struct file *filp) |
328 | { | |
329 | filp->private_data = inode->i_private; | |
330 | ||
331 | return 0; | |
332 | } | |
333 | ||
334 | static ssize_t blk_msg_write(struct file *filp, const char __user *buffer, | |
335 | size_t count, loff_t *ppos) | |
336 | { | |
337 | char *msg; | |
338 | struct blk_trace *bt; | |
339 | ||
7635b03a | 340 | if (count >= BLK_TN_MAX_MSG) |
02c62304 AB |
341 | return -EINVAL; |
342 | ||
a4b3ada8 | 343 | msg = kmalloc(count + 1, GFP_KERNEL); |
02c62304 AB |
344 | if (msg == NULL) |
345 | return -ENOMEM; | |
346 | ||
347 | if (copy_from_user(msg, buffer, count)) { | |
348 | kfree(msg); | |
349 | return -EFAULT; | |
350 | } | |
351 | ||
a4b3ada8 | 352 | msg[count] = '\0'; |
02c62304 AB |
353 | bt = filp->private_data; |
354 | __trace_note_message(bt, "%s", msg); | |
355 | kfree(msg); | |
356 | ||
357 | return count; | |
358 | } | |
359 | ||
360 | static const struct file_operations blk_msg_fops = { | |
361 | .owner = THIS_MODULE, | |
362 | .open = blk_msg_open, | |
363 | .write = blk_msg_write, | |
364 | }; | |
365 | ||
2056a782 JA |
366 | /* |
367 | * Keep track of how many times we encountered a full subbuffer, to aid | |
368 | * the user space app in telling how many lost events there were. | |
369 | */ | |
370 | static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf, | |
371 | void *prev_subbuf, size_t prev_padding) | |
372 | { | |
373 | struct blk_trace *bt; | |
374 | ||
375 | if (!relay_buf_full(buf)) | |
376 | return 1; | |
377 | ||
378 | bt = buf->chan->private_data; | |
379 | atomic_inc(&bt->dropped); | |
380 | return 0; | |
381 | } | |
382 | ||
383 | static int blk_remove_buf_file_callback(struct dentry *dentry) | |
384 | { | |
385 | debugfs_remove(dentry); | |
f48fc4d3 | 386 | |
2056a782 JA |
387 | return 0; |
388 | } | |
389 | ||
390 | static struct dentry *blk_create_buf_file_callback(const char *filename, | |
391 | struct dentry *parent, | |
392 | int mode, | |
393 | struct rchan_buf *buf, | |
394 | int *is_global) | |
395 | { | |
396 | return debugfs_create_file(filename, mode, parent, buf, | |
397 | &relay_file_operations); | |
398 | } | |
399 | ||
400 | static struct rchan_callbacks blk_relay_callbacks = { | |
401 | .subbuf_start = blk_subbuf_start_callback, | |
402 | .create_buf_file = blk_create_buf_file_callback, | |
403 | .remove_buf_file = blk_remove_buf_file_callback, | |
404 | }; | |
405 | ||
9908c309 LZ |
406 | static void blk_trace_setup_lba(struct blk_trace *bt, |
407 | struct block_device *bdev) | |
408 | { | |
409 | struct hd_struct *part = NULL; | |
410 | ||
411 | if (bdev) | |
412 | part = bdev->bd_part; | |
413 | ||
414 | if (part) { | |
415 | bt->start_lba = part->start_sect; | |
416 | bt->end_lba = part->start_sect + part->nr_sects; | |
417 | } else { | |
418 | bt->start_lba = 0; | |
419 | bt->end_lba = -1ULL; | |
420 | } | |
421 | } | |
422 | ||
2056a782 JA |
423 | /* |
424 | * Setup everything required to start tracing | |
425 | */ | |
6da127ad | 426 | int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, |
d0deef5b SD |
427 | struct block_device *bdev, |
428 | struct blk_user_trace_setup *buts) | |
2056a782 | 429 | { |
2056a782 JA |
430 | struct blk_trace *old_bt, *bt = NULL; |
431 | struct dentry *dir = NULL; | |
2056a782 JA |
432 | int ret, i; |
433 | ||
171044d4 | 434 | if (!buts->buf_size || !buts->buf_nr) |
2056a782 JA |
435 | return -EINVAL; |
436 | ||
0497b345 JA |
437 | strncpy(buts->name, name, BLKTRACE_BDEV_SIZE); |
438 | buts->name[BLKTRACE_BDEV_SIZE - 1] = '\0'; | |
2056a782 JA |
439 | |
440 | /* | |
441 | * some device names have larger paths - convert the slashes | |
442 | * to underscores for this to work as expected | |
443 | */ | |
171044d4 AB |
444 | for (i = 0; i < strlen(buts->name); i++) |
445 | if (buts->name[i] == '/') | |
446 | buts->name[i] = '_'; | |
2056a782 | 447 | |
2056a782 JA |
448 | bt = kzalloc(sizeof(*bt), GFP_KERNEL); |
449 | if (!bt) | |
ad5dd549 | 450 | return -ENOMEM; |
2056a782 | 451 | |
ad5dd549 | 452 | ret = -ENOMEM; |
2056a782 JA |
453 | bt->sequence = alloc_percpu(unsigned long); |
454 | if (!bt->sequence) | |
455 | goto err; | |
456 | ||
313e458f | 457 | bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); |
64565911 JA |
458 | if (!bt->msg_data) |
459 | goto err; | |
460 | ||
2056a782 | 461 | ret = -ENOENT; |
f48fc4d3 | 462 | |
b5230b56 | 463 | mutex_lock(&blk_tree_mutex); |
f48fc4d3 JA |
464 | if (!blk_tree_root) { |
465 | blk_tree_root = debugfs_create_dir("block", NULL); | |
b5230b56 LZ |
466 | if (!blk_tree_root) { |
467 | mutex_unlock(&blk_tree_mutex); | |
1a17662e | 468 | goto err; |
b5230b56 | 469 | } |
f48fc4d3 | 470 | } |
b5230b56 | 471 | mutex_unlock(&blk_tree_mutex); |
f48fc4d3 JA |
472 | |
473 | dir = debugfs_create_dir(buts->name, blk_tree_root); | |
474 | ||
2056a782 JA |
475 | if (!dir) |
476 | goto err; | |
477 | ||
478 | bt->dir = dir; | |
6da127ad | 479 | bt->dev = dev; |
2056a782 JA |
480 | atomic_set(&bt->dropped, 0); |
481 | ||
482 | ret = -EIO; | |
939b3669 ACM |
483 | bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt, |
484 | &blk_dropped_fops); | |
2056a782 JA |
485 | if (!bt->dropped_file) |
486 | goto err; | |
487 | ||
02c62304 AB |
488 | bt->msg_file = debugfs_create_file("msg", 0222, dir, bt, &blk_msg_fops); |
489 | if (!bt->msg_file) | |
490 | goto err; | |
491 | ||
171044d4 AB |
492 | bt->rchan = relay_open("trace", dir, buts->buf_size, |
493 | buts->buf_nr, &blk_relay_callbacks, bt); | |
2056a782 JA |
494 | if (!bt->rchan) |
495 | goto err; | |
2056a782 | 496 | |
171044d4 | 497 | bt->act_mask = buts->act_mask; |
2056a782 JA |
498 | if (!bt->act_mask) |
499 | bt->act_mask = (u16) -1; | |
500 | ||
9908c309 | 501 | blk_trace_setup_lba(bt, bdev); |
2056a782 | 502 | |
d0deef5b SD |
503 | /* overwrite with user settings */ |
504 | if (buts->start_lba) | |
505 | bt->start_lba = buts->start_lba; | |
506 | if (buts->end_lba) | |
507 | bt->end_lba = buts->end_lba; | |
508 | ||
171044d4 | 509 | bt->pid = buts->pid; |
2056a782 JA |
510 | bt->trace_state = Blktrace_setup; |
511 | ||
512 | ret = -EBUSY; | |
513 | old_bt = xchg(&q->blk_trace, bt); | |
514 | if (old_bt) { | |
515 | (void) xchg(&q->blk_trace, old_bt); | |
516 | goto err; | |
517 | } | |
518 | ||
17ba97e3 | 519 | if (atomic_inc_return(&blk_probes_ref) == 1) |
cbe28296 LZ |
520 | blk_register_tracepoints(); |
521 | ||
2056a782 JA |
522 | return 0; |
523 | err: | |
ad5dd549 | 524 | blk_trace_free(bt); |
2056a782 JA |
525 | return ret; |
526 | } | |
171044d4 | 527 | |
6da127ad | 528 | int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, |
d0deef5b | 529 | struct block_device *bdev, |
6da127ad | 530 | char __user *arg) |
171044d4 AB |
531 | { |
532 | struct blk_user_trace_setup buts; | |
533 | int ret; | |
534 | ||
535 | ret = copy_from_user(&buts, arg, sizeof(buts)); | |
536 | if (ret) | |
537 | return -EFAULT; | |
538 | ||
d0deef5b | 539 | ret = do_blk_trace_setup(q, name, dev, bdev, &buts); |
171044d4 AB |
540 | if (ret) |
541 | return ret; | |
542 | ||
543 | if (copy_to_user(arg, &buts, sizeof(buts))) | |
544 | return -EFAULT; | |
545 | ||
546 | return 0; | |
547 | } | |
6da127ad | 548 | EXPORT_SYMBOL_GPL(blk_trace_setup); |
2056a782 | 549 | |
6da127ad | 550 | int blk_trace_startstop(struct request_queue *q, int start) |
2056a782 | 551 | { |
2056a782 | 552 | int ret; |
939b3669 | 553 | struct blk_trace *bt = q->blk_trace; |
2056a782 | 554 | |
939b3669 | 555 | if (bt == NULL) |
2056a782 JA |
556 | return -EINVAL; |
557 | ||
558 | /* | |
559 | * For starting a trace, we can transition from a setup or stopped | |
560 | * trace. For stopping a trace, the state must be running | |
561 | */ | |
562 | ret = -EINVAL; | |
563 | if (start) { | |
564 | if (bt->trace_state == Blktrace_setup || | |
565 | bt->trace_state == Blktrace_stopped) { | |
566 | blktrace_seq++; | |
567 | smp_mb(); | |
568 | bt->trace_state = Blktrace_running; | |
be1c6341 OK |
569 | |
570 | trace_note_time(bt); | |
2056a782 JA |
571 | ret = 0; |
572 | } | |
573 | } else { | |
574 | if (bt->trace_state == Blktrace_running) { | |
575 | bt->trace_state = Blktrace_stopped; | |
576 | relay_flush(bt->rchan); | |
577 | ret = 0; | |
578 | } | |
579 | } | |
580 | ||
581 | return ret; | |
582 | } | |
6da127ad | 583 | EXPORT_SYMBOL_GPL(blk_trace_startstop); |
2056a782 JA |
584 | |
585 | /** | |
586 | * blk_trace_ioctl: - handle the ioctls associated with tracing | |
587 | * @bdev: the block device | |
ef18012b | 588 | * @cmd: the ioctl cmd |
2056a782 JA |
589 | * @arg: the argument data, if any |
590 | * | |
591 | **/ | |
592 | int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) | |
593 | { | |
165125e1 | 594 | struct request_queue *q; |
2056a782 | 595 | int ret, start = 0; |
6da127ad | 596 | char b[BDEVNAME_SIZE]; |
2056a782 JA |
597 | |
598 | q = bdev_get_queue(bdev); | |
599 | if (!q) | |
600 | return -ENXIO; | |
601 | ||
602 | mutex_lock(&bdev->bd_mutex); | |
603 | ||
604 | switch (cmd) { | |
605 | case BLKTRACESETUP: | |
f36f21ec | 606 | bdevname(bdev, b); |
d0deef5b | 607 | ret = blk_trace_setup(q, b, bdev->bd_dev, bdev, arg); |
2056a782 JA |
608 | break; |
609 | case BLKTRACESTART: | |
610 | start = 1; | |
611 | case BLKTRACESTOP: | |
612 | ret = blk_trace_startstop(q, start); | |
613 | break; | |
614 | case BLKTRACETEARDOWN: | |
615 | ret = blk_trace_remove(q); | |
616 | break; | |
617 | default: | |
618 | ret = -ENOTTY; | |
619 | break; | |
620 | } | |
621 | ||
622 | mutex_unlock(&bdev->bd_mutex); | |
623 | return ret; | |
624 | } | |
625 | ||
626 | /** | |
627 | * blk_trace_shutdown: - stop and cleanup trace structures | |
628 | * @q: the request queue associated with the device | |
629 | * | |
630 | **/ | |
165125e1 | 631 | void blk_trace_shutdown(struct request_queue *q) |
2056a782 | 632 | { |
6c5c9341 AD |
633 | if (q->blk_trace) { |
634 | blk_trace_startstop(q, 0); | |
635 | blk_trace_remove(q); | |
636 | } | |
2056a782 | 637 | } |
5f3ea37c ACM |
638 | |
639 | /* | |
640 | * blktrace probes | |
641 | */ | |
642 | ||
643 | /** | |
644 | * blk_add_trace_rq - Add a trace for a request oriented action | |
645 | * @q: queue the io is for | |
646 | * @rq: the source request | |
647 | * @what: the action | |
648 | * | |
649 | * Description: | |
650 | * Records an action against a request. Will log the bio offset + size. | |
651 | * | |
652 | **/ | |
653 | static void blk_add_trace_rq(struct request_queue *q, struct request *rq, | |
654 | u32 what) | |
655 | { | |
656 | struct blk_trace *bt = q->blk_trace; | |
657 | int rw = rq->cmd_flags & 0x03; | |
658 | ||
659 | if (likely(!bt)) | |
660 | return; | |
661 | ||
662 | if (blk_discard_rq(rq)) | |
663 | rw |= (1 << BIO_RW_DISCARD); | |
664 | ||
665 | if (blk_pc_request(rq)) { | |
666 | what |= BLK_TC_ACT(BLK_TC_PC); | |
2e46e8b2 TH |
667 | __blk_add_trace(bt, 0, blk_rq_bytes(rq), rw, |
668 | what, rq->errors, rq->cmd_len, rq->cmd); | |
5f3ea37c ACM |
669 | } else { |
670 | what |= BLK_TC_ACT(BLK_TC_FS); | |
2e46e8b2 TH |
671 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), rw, |
672 | what, rq->errors, 0, NULL); | |
5f3ea37c ACM |
673 | } |
674 | } | |
675 | ||
676 | static void blk_add_trace_rq_abort(struct request_queue *q, struct request *rq) | |
677 | { | |
678 | blk_add_trace_rq(q, rq, BLK_TA_ABORT); | |
679 | } | |
680 | ||
681 | static void blk_add_trace_rq_insert(struct request_queue *q, struct request *rq) | |
682 | { | |
683 | blk_add_trace_rq(q, rq, BLK_TA_INSERT); | |
684 | } | |
685 | ||
686 | static void blk_add_trace_rq_issue(struct request_queue *q, struct request *rq) | |
687 | { | |
688 | blk_add_trace_rq(q, rq, BLK_TA_ISSUE); | |
689 | } | |
690 | ||
939b3669 ACM |
691 | static void blk_add_trace_rq_requeue(struct request_queue *q, |
692 | struct request *rq) | |
5f3ea37c ACM |
693 | { |
694 | blk_add_trace_rq(q, rq, BLK_TA_REQUEUE); | |
695 | } | |
696 | ||
939b3669 ACM |
697 | static void blk_add_trace_rq_complete(struct request_queue *q, |
698 | struct request *rq) | |
5f3ea37c ACM |
699 | { |
700 | blk_add_trace_rq(q, rq, BLK_TA_COMPLETE); | |
701 | } | |
702 | ||
703 | /** | |
704 | * blk_add_trace_bio - Add a trace for a bio oriented action | |
705 | * @q: queue the io is for | |
706 | * @bio: the source bio | |
707 | * @what: the action | |
708 | * | |
709 | * Description: | |
710 | * Records an action against a bio. Will log the bio offset + size. | |
711 | * | |
712 | **/ | |
713 | static void blk_add_trace_bio(struct request_queue *q, struct bio *bio, | |
714 | u32 what) | |
715 | { | |
716 | struct blk_trace *bt = q->blk_trace; | |
717 | ||
718 | if (likely(!bt)) | |
719 | return; | |
720 | ||
721 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, | |
722 | !bio_flagged(bio, BIO_UPTODATE), 0, NULL); | |
723 | } | |
724 | ||
725 | static void blk_add_trace_bio_bounce(struct request_queue *q, struct bio *bio) | |
726 | { | |
727 | blk_add_trace_bio(q, bio, BLK_TA_BOUNCE); | |
728 | } | |
729 | ||
730 | static void blk_add_trace_bio_complete(struct request_queue *q, struct bio *bio) | |
731 | { | |
732 | blk_add_trace_bio(q, bio, BLK_TA_COMPLETE); | |
733 | } | |
734 | ||
939b3669 ACM |
735 | static void blk_add_trace_bio_backmerge(struct request_queue *q, |
736 | struct bio *bio) | |
5f3ea37c ACM |
737 | { |
738 | blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE); | |
739 | } | |
740 | ||
939b3669 ACM |
741 | static void blk_add_trace_bio_frontmerge(struct request_queue *q, |
742 | struct bio *bio) | |
5f3ea37c ACM |
743 | { |
744 | blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE); | |
745 | } | |
746 | ||
747 | static void blk_add_trace_bio_queue(struct request_queue *q, struct bio *bio) | |
748 | { | |
749 | blk_add_trace_bio(q, bio, BLK_TA_QUEUE); | |
750 | } | |
751 | ||
939b3669 ACM |
752 | static void blk_add_trace_getrq(struct request_queue *q, |
753 | struct bio *bio, int rw) | |
5f3ea37c ACM |
754 | { |
755 | if (bio) | |
756 | blk_add_trace_bio(q, bio, BLK_TA_GETRQ); | |
757 | else { | |
758 | struct blk_trace *bt = q->blk_trace; | |
759 | ||
760 | if (bt) | |
761 | __blk_add_trace(bt, 0, 0, rw, BLK_TA_GETRQ, 0, 0, NULL); | |
762 | } | |
763 | } | |
764 | ||
765 | ||
939b3669 ACM |
766 | static void blk_add_trace_sleeprq(struct request_queue *q, |
767 | struct bio *bio, int rw) | |
5f3ea37c ACM |
768 | { |
769 | if (bio) | |
770 | blk_add_trace_bio(q, bio, BLK_TA_SLEEPRQ); | |
771 | else { | |
772 | struct blk_trace *bt = q->blk_trace; | |
773 | ||
774 | if (bt) | |
939b3669 ACM |
775 | __blk_add_trace(bt, 0, 0, rw, BLK_TA_SLEEPRQ, |
776 | 0, 0, NULL); | |
5f3ea37c ACM |
777 | } |
778 | } | |
779 | ||
780 | static void blk_add_trace_plug(struct request_queue *q) | |
781 | { | |
782 | struct blk_trace *bt = q->blk_trace; | |
783 | ||
784 | if (bt) | |
785 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_PLUG, 0, 0, NULL); | |
786 | } | |
787 | ||
788 | static void blk_add_trace_unplug_io(struct request_queue *q) | |
789 | { | |
790 | struct blk_trace *bt = q->blk_trace; | |
791 | ||
792 | if (bt) { | |
793 | unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; | |
794 | __be64 rpdu = cpu_to_be64(pdu); | |
795 | ||
796 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_IO, 0, | |
797 | sizeof(rpdu), &rpdu); | |
798 | } | |
799 | } | |
800 | ||
801 | static void blk_add_trace_unplug_timer(struct request_queue *q) | |
802 | { | |
803 | struct blk_trace *bt = q->blk_trace; | |
804 | ||
805 | if (bt) { | |
806 | unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; | |
807 | __be64 rpdu = cpu_to_be64(pdu); | |
808 | ||
809 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_TIMER, 0, | |
810 | sizeof(rpdu), &rpdu); | |
811 | } | |
812 | } | |
813 | ||
814 | static void blk_add_trace_split(struct request_queue *q, struct bio *bio, | |
815 | unsigned int pdu) | |
816 | { | |
817 | struct blk_trace *bt = q->blk_trace; | |
818 | ||
819 | if (bt) { | |
820 | __be64 rpdu = cpu_to_be64(pdu); | |
821 | ||
822 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, | |
823 | BLK_TA_SPLIT, !bio_flagged(bio, BIO_UPTODATE), | |
824 | sizeof(rpdu), &rpdu); | |
825 | } | |
826 | } | |
827 | ||
828 | /** | |
829 | * blk_add_trace_remap - Add a trace for a remap operation | |
830 | * @q: queue the io is for | |
831 | * @bio: the source bio | |
832 | * @dev: target device | |
a42aaa3b | 833 | * @from: source sector |
5f3ea37c ACM |
834 | * |
835 | * Description: | |
836 | * Device mapper or raid target sometimes need to split a bio because | |
837 | * it spans a stripe (or similar). Add a trace for that action. | |
838 | * | |
839 | **/ | |
840 | static void blk_add_trace_remap(struct request_queue *q, struct bio *bio, | |
22a7c31a | 841 | dev_t dev, sector_t from) |
5f3ea37c ACM |
842 | { |
843 | struct blk_trace *bt = q->blk_trace; | |
844 | struct blk_io_trace_remap r; | |
845 | ||
846 | if (likely(!bt)) | |
847 | return; | |
848 | ||
a42aaa3b AB |
849 | r.device_from = cpu_to_be32(dev); |
850 | r.device_to = cpu_to_be32(bio->bi_bdev->bd_dev); | |
851 | r.sector_from = cpu_to_be64(from); | |
5f3ea37c | 852 | |
22a7c31a AB |
853 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, |
854 | BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), | |
855 | sizeof(r), &r); | |
5f3ea37c ACM |
856 | } |
857 | ||
858 | /** | |
859 | * blk_add_driver_data - Add binary message with driver-specific data | |
860 | * @q: queue the io is for | |
861 | * @rq: io request | |
862 | * @data: driver-specific data | |
863 | * @len: length of driver-specific data | |
864 | * | |
865 | * Description: | |
866 | * Some drivers might want to write driver-specific data per request. | |
867 | * | |
868 | **/ | |
869 | void blk_add_driver_data(struct request_queue *q, | |
870 | struct request *rq, | |
871 | void *data, size_t len) | |
872 | { | |
873 | struct blk_trace *bt = q->blk_trace; | |
874 | ||
875 | if (likely(!bt)) | |
876 | return; | |
877 | ||
878 | if (blk_pc_request(rq)) | |
2e46e8b2 TH |
879 | __blk_add_trace(bt, 0, blk_rq_bytes(rq), 0, |
880 | BLK_TA_DRV_DATA, rq->errors, len, data); | |
5f3ea37c | 881 | else |
2e46e8b2 TH |
882 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), 0, |
883 | BLK_TA_DRV_DATA, rq->errors, len, data); | |
5f3ea37c ACM |
884 | } |
885 | EXPORT_SYMBOL_GPL(blk_add_driver_data); | |
886 | ||
3c289ba7 | 887 | static void blk_register_tracepoints(void) |
5f3ea37c ACM |
888 | { |
889 | int ret; | |
890 | ||
891 | ret = register_trace_block_rq_abort(blk_add_trace_rq_abort); | |
892 | WARN_ON(ret); | |
893 | ret = register_trace_block_rq_insert(blk_add_trace_rq_insert); | |
894 | WARN_ON(ret); | |
895 | ret = register_trace_block_rq_issue(blk_add_trace_rq_issue); | |
896 | WARN_ON(ret); | |
897 | ret = register_trace_block_rq_requeue(blk_add_trace_rq_requeue); | |
898 | WARN_ON(ret); | |
899 | ret = register_trace_block_rq_complete(blk_add_trace_rq_complete); | |
900 | WARN_ON(ret); | |
901 | ret = register_trace_block_bio_bounce(blk_add_trace_bio_bounce); | |
902 | WARN_ON(ret); | |
903 | ret = register_trace_block_bio_complete(blk_add_trace_bio_complete); | |
904 | WARN_ON(ret); | |
905 | ret = register_trace_block_bio_backmerge(blk_add_trace_bio_backmerge); | |
906 | WARN_ON(ret); | |
907 | ret = register_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge); | |
908 | WARN_ON(ret); | |
909 | ret = register_trace_block_bio_queue(blk_add_trace_bio_queue); | |
910 | WARN_ON(ret); | |
911 | ret = register_trace_block_getrq(blk_add_trace_getrq); | |
912 | WARN_ON(ret); | |
913 | ret = register_trace_block_sleeprq(blk_add_trace_sleeprq); | |
914 | WARN_ON(ret); | |
915 | ret = register_trace_block_plug(blk_add_trace_plug); | |
916 | WARN_ON(ret); | |
917 | ret = register_trace_block_unplug_timer(blk_add_trace_unplug_timer); | |
918 | WARN_ON(ret); | |
919 | ret = register_trace_block_unplug_io(blk_add_trace_unplug_io); | |
920 | WARN_ON(ret); | |
921 | ret = register_trace_block_split(blk_add_trace_split); | |
922 | WARN_ON(ret); | |
923 | ret = register_trace_block_remap(blk_add_trace_remap); | |
924 | WARN_ON(ret); | |
5f3ea37c ACM |
925 | } |
926 | ||
927 | static void blk_unregister_tracepoints(void) | |
928 | { | |
929 | unregister_trace_block_remap(blk_add_trace_remap); | |
930 | unregister_trace_block_split(blk_add_trace_split); | |
931 | unregister_trace_block_unplug_io(blk_add_trace_unplug_io); | |
932 | unregister_trace_block_unplug_timer(blk_add_trace_unplug_timer); | |
933 | unregister_trace_block_plug(blk_add_trace_plug); | |
934 | unregister_trace_block_sleeprq(blk_add_trace_sleeprq); | |
935 | unregister_trace_block_getrq(blk_add_trace_getrq); | |
936 | unregister_trace_block_bio_queue(blk_add_trace_bio_queue); | |
937 | unregister_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge); | |
938 | unregister_trace_block_bio_backmerge(blk_add_trace_bio_backmerge); | |
939 | unregister_trace_block_bio_complete(blk_add_trace_bio_complete); | |
940 | unregister_trace_block_bio_bounce(blk_add_trace_bio_bounce); | |
941 | unregister_trace_block_rq_complete(blk_add_trace_rq_complete); | |
942 | unregister_trace_block_rq_requeue(blk_add_trace_rq_requeue); | |
943 | unregister_trace_block_rq_issue(blk_add_trace_rq_issue); | |
944 | unregister_trace_block_rq_insert(blk_add_trace_rq_insert); | |
945 | unregister_trace_block_rq_abort(blk_add_trace_rq_abort); | |
946 | ||
947 | tracepoint_synchronize_unregister(); | |
948 | } | |
c71a8961 ACM |
949 | |
950 | /* | |
951 | * struct blk_io_tracer formatting routines | |
952 | */ | |
953 | ||
954 | static void fill_rwbs(char *rwbs, const struct blk_io_trace *t) | |
955 | { | |
157f9c00 | 956 | int i = 0; |
65796348 | 957 | int tc = t->action >> BLK_TC_SHIFT; |
157f9c00 | 958 | |
18cea459 LZ |
959 | if (t->action == BLK_TN_MESSAGE) { |
960 | rwbs[i++] = 'N'; | |
961 | goto out; | |
962 | } | |
963 | ||
65796348 | 964 | if (tc & BLK_TC_DISCARD) |
157f9c00 | 965 | rwbs[i++] = 'D'; |
65796348 | 966 | else if (tc & BLK_TC_WRITE) |
157f9c00 ACM |
967 | rwbs[i++] = 'W'; |
968 | else if (t->bytes) | |
969 | rwbs[i++] = 'R'; | |
970 | else | |
971 | rwbs[i++] = 'N'; | |
972 | ||
65796348 | 973 | if (tc & BLK_TC_AHEAD) |
157f9c00 | 974 | rwbs[i++] = 'A'; |
65796348 | 975 | if (tc & BLK_TC_BARRIER) |
157f9c00 | 976 | rwbs[i++] = 'B'; |
65796348 | 977 | if (tc & BLK_TC_SYNC) |
157f9c00 | 978 | rwbs[i++] = 'S'; |
65796348 | 979 | if (tc & BLK_TC_META) |
157f9c00 | 980 | rwbs[i++] = 'M'; |
18cea459 | 981 | out: |
157f9c00 | 982 | rwbs[i] = '\0'; |
c71a8961 ACM |
983 | } |
984 | ||
985 | static inline | |
986 | const struct blk_io_trace *te_blk_io_trace(const struct trace_entry *ent) | |
987 | { | |
988 | return (const struct blk_io_trace *)ent; | |
989 | } | |
990 | ||
991 | static inline const void *pdu_start(const struct trace_entry *ent) | |
992 | { | |
993 | return te_blk_io_trace(ent) + 1; | |
994 | } | |
995 | ||
66de7792 LZ |
996 | static inline u32 t_action(const struct trace_entry *ent) |
997 | { | |
998 | return te_blk_io_trace(ent)->action; | |
999 | } | |
1000 | ||
1001 | static inline u32 t_bytes(const struct trace_entry *ent) | |
1002 | { | |
1003 | return te_blk_io_trace(ent)->bytes; | |
1004 | } | |
1005 | ||
c71a8961 ACM |
1006 | static inline u32 t_sec(const struct trace_entry *ent) |
1007 | { | |
1008 | return te_blk_io_trace(ent)->bytes >> 9; | |
1009 | } | |
1010 | ||
1011 | static inline unsigned long long t_sector(const struct trace_entry *ent) | |
1012 | { | |
1013 | return te_blk_io_trace(ent)->sector; | |
1014 | } | |
1015 | ||
1016 | static inline __u16 t_error(const struct trace_entry *ent) | |
1017 | { | |
e0dc81be | 1018 | return te_blk_io_trace(ent)->error; |
c71a8961 ACM |
1019 | } |
1020 | ||
1021 | static __u64 get_pdu_int(const struct trace_entry *ent) | |
1022 | { | |
1023 | const __u64 *val = pdu_start(ent); | |
1024 | return be64_to_cpu(*val); | |
1025 | } | |
1026 | ||
1027 | static void get_pdu_remap(const struct trace_entry *ent, | |
1028 | struct blk_io_trace_remap *r) | |
1029 | { | |
1030 | const struct blk_io_trace_remap *__r = pdu_start(ent); | |
a42aaa3b | 1031 | __u64 sector_from = __r->sector_from; |
c71a8961 | 1032 | |
c71a8961 | 1033 | r->device_from = be32_to_cpu(__r->device_from); |
a42aaa3b AB |
1034 | r->device_to = be32_to_cpu(__r->device_to); |
1035 | r->sector_from = be64_to_cpu(sector_from); | |
c71a8961 ACM |
1036 | } |
1037 | ||
b6a4b0c3 LZ |
1038 | typedef int (blk_log_action_t) (struct trace_iterator *iter, const char *act); |
1039 | ||
1040 | static int blk_log_action_classic(struct trace_iterator *iter, const char *act) | |
c71a8961 ACM |
1041 | { |
1042 | char rwbs[6]; | |
35ac51bf LZ |
1043 | unsigned long long ts = iter->ts; |
1044 | unsigned long nsec_rem = do_div(ts, NSEC_PER_SEC); | |
c71a8961 | 1045 | unsigned secs = (unsigned long)ts; |
b6a4b0c3 | 1046 | const struct blk_io_trace *t = te_blk_io_trace(iter->ent); |
c71a8961 ACM |
1047 | |
1048 | fill_rwbs(rwbs, t); | |
1049 | ||
1050 | return trace_seq_printf(&iter->seq, | |
35ac51bf | 1051 | "%3d,%-3d %2d %5d.%09lu %5u %2s %3s ", |
c71a8961 | 1052 | MAJOR(t->device), MINOR(t->device), iter->cpu, |
b6a4b0c3 | 1053 | secs, nsec_rem, iter->ent->pid, act, rwbs); |
c71a8961 ACM |
1054 | } |
1055 | ||
b6a4b0c3 | 1056 | static int blk_log_action(struct trace_iterator *iter, const char *act) |
c71a8961 ACM |
1057 | { |
1058 | char rwbs[6]; | |
b6a4b0c3 LZ |
1059 | const struct blk_io_trace *t = te_blk_io_trace(iter->ent); |
1060 | ||
c71a8961 | 1061 | fill_rwbs(rwbs, t); |
b6a4b0c3 | 1062 | return trace_seq_printf(&iter->seq, "%3d,%-3d %2s %3s ", |
c71a8961 ACM |
1063 | MAJOR(t->device), MINOR(t->device), act, rwbs); |
1064 | } | |
1065 | ||
66de7792 LZ |
1066 | static int blk_log_dump_pdu(struct trace_seq *s, const struct trace_entry *ent) |
1067 | { | |
04986257 | 1068 | const unsigned char *pdu_buf; |
66de7792 LZ |
1069 | int pdu_len; |
1070 | int i, end, ret; | |
1071 | ||
1072 | pdu_buf = pdu_start(ent); | |
1073 | pdu_len = te_blk_io_trace(ent)->pdu_len; | |
1074 | ||
1075 | if (!pdu_len) | |
1076 | return 1; | |
1077 | ||
1078 | /* find the last zero that needs to be printed */ | |
1079 | for (end = pdu_len - 1; end >= 0; end--) | |
1080 | if (pdu_buf[end]) | |
1081 | break; | |
1082 | end++; | |
1083 | ||
1084 | if (!trace_seq_putc(s, '(')) | |
1085 | return 0; | |
1086 | ||
1087 | for (i = 0; i < pdu_len; i++) { | |
1088 | ||
1089 | ret = trace_seq_printf(s, "%s%02x", | |
1090 | i == 0 ? "" : " ", pdu_buf[i]); | |
1091 | if (!ret) | |
1092 | return ret; | |
1093 | ||
1094 | /* | |
1095 | * stop when the rest is just zeroes and indicate so | |
1096 | * with a ".." appended | |
1097 | */ | |
1098 | if (i == end && end != pdu_len - 1) | |
1099 | return trace_seq_puts(s, " ..) "); | |
1100 | } | |
1101 | ||
1102 | return trace_seq_puts(s, ") "); | |
1103 | } | |
1104 | ||
c71a8961 ACM |
1105 | static int blk_log_generic(struct trace_seq *s, const struct trace_entry *ent) |
1106 | { | |
4ca53085 SR |
1107 | char cmd[TASK_COMM_LEN]; |
1108 | ||
1109 | trace_find_cmdline(ent->pid, cmd); | |
c71a8961 | 1110 | |
66de7792 LZ |
1111 | if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { |
1112 | int ret; | |
1113 | ||
1114 | ret = trace_seq_printf(s, "%u ", t_bytes(ent)); | |
1115 | if (!ret) | |
1116 | return 0; | |
1117 | ret = blk_log_dump_pdu(s, ent); | |
1118 | if (!ret) | |
1119 | return 0; | |
1120 | return trace_seq_printf(s, "[%s]\n", cmd); | |
1121 | } else { | |
1122 | if (t_sec(ent)) | |
1123 | return trace_seq_printf(s, "%llu + %u [%s]\n", | |
1124 | t_sector(ent), t_sec(ent), cmd); | |
1125 | return trace_seq_printf(s, "[%s]\n", cmd); | |
1126 | } | |
c71a8961 ACM |
1127 | } |
1128 | ||
157f9c00 ACM |
1129 | static int blk_log_with_error(struct trace_seq *s, |
1130 | const struct trace_entry *ent) | |
c71a8961 | 1131 | { |
66de7792 LZ |
1132 | if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { |
1133 | int ret; | |
1134 | ||
1135 | ret = blk_log_dump_pdu(s, ent); | |
1136 | if (ret) | |
1137 | return trace_seq_printf(s, "[%d]\n", t_error(ent)); | |
1138 | return 0; | |
1139 | } else { | |
1140 | if (t_sec(ent)) | |
1141 | return trace_seq_printf(s, "%llu + %u [%d]\n", | |
1142 | t_sector(ent), | |
1143 | t_sec(ent), t_error(ent)); | |
1144 | return trace_seq_printf(s, "%llu [%d]\n", | |
1145 | t_sector(ent), t_error(ent)); | |
1146 | } | |
c71a8961 ACM |
1147 | } |
1148 | ||
1149 | static int blk_log_remap(struct trace_seq *s, const struct trace_entry *ent) | |
1150 | { | |
a42aaa3b | 1151 | struct blk_io_trace_remap r = { .device_from = 0, }; |
c71a8961 ACM |
1152 | |
1153 | get_pdu_remap(ent, &r); | |
1154 | return trace_seq_printf(s, "%llu + %u <- (%d,%d) %llu\n", | |
a42aaa3b AB |
1155 | t_sector(ent), t_sec(ent), |
1156 | MAJOR(r.device_from), MINOR(r.device_from), | |
1157 | (unsigned long long)r.sector_from); | |
c71a8961 ACM |
1158 | } |
1159 | ||
1160 | static int blk_log_plug(struct trace_seq *s, const struct trace_entry *ent) | |
1161 | { | |
4ca53085 SR |
1162 | char cmd[TASK_COMM_LEN]; |
1163 | ||
1164 | trace_find_cmdline(ent->pid, cmd); | |
1165 | ||
1166 | return trace_seq_printf(s, "[%s]\n", cmd); | |
c71a8961 ACM |
1167 | } |
1168 | ||
1169 | static int blk_log_unplug(struct trace_seq *s, const struct trace_entry *ent) | |
1170 | { | |
4ca53085 SR |
1171 | char cmd[TASK_COMM_LEN]; |
1172 | ||
1173 | trace_find_cmdline(ent->pid, cmd); | |
1174 | ||
1175 | return trace_seq_printf(s, "[%s] %llu\n", cmd, get_pdu_int(ent)); | |
c71a8961 ACM |
1176 | } |
1177 | ||
1178 | static int blk_log_split(struct trace_seq *s, const struct trace_entry *ent) | |
1179 | { | |
4ca53085 SR |
1180 | char cmd[TASK_COMM_LEN]; |
1181 | ||
1182 | trace_find_cmdline(ent->pid, cmd); | |
1183 | ||
c71a8961 | 1184 | return trace_seq_printf(s, "%llu / %llu [%s]\n", t_sector(ent), |
4ca53085 | 1185 | get_pdu_int(ent), cmd); |
c71a8961 ACM |
1186 | } |
1187 | ||
18cea459 LZ |
1188 | static int blk_log_msg(struct trace_seq *s, const struct trace_entry *ent) |
1189 | { | |
1190 | int ret; | |
1191 | const struct blk_io_trace *t = te_blk_io_trace(ent); | |
1192 | ||
1193 | ret = trace_seq_putmem(s, t + 1, t->pdu_len); | |
1194 | if (ret) | |
1195 | return trace_seq_putc(s, '\n'); | |
1196 | return ret; | |
1197 | } | |
1198 | ||
c71a8961 ACM |
1199 | /* |
1200 | * struct tracer operations | |
1201 | */ | |
1202 | ||
1203 | static void blk_tracer_print_header(struct seq_file *m) | |
1204 | { | |
1205 | if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) | |
1206 | return; | |
1207 | seq_puts(m, "# DEV CPU TIMESTAMP PID ACT FLG\n" | |
1208 | "# | | | | | |\n"); | |
1209 | } | |
1210 | ||
1211 | static void blk_tracer_start(struct trace_array *tr) | |
1212 | { | |
ad5dd549 | 1213 | blk_tracer_enabled = true; |
c71a8961 ACM |
1214 | } |
1215 | ||
1216 | static int blk_tracer_init(struct trace_array *tr) | |
1217 | { | |
1218 | blk_tr = tr; | |
1219 | blk_tracer_start(tr); | |
c71a8961 ACM |
1220 | return 0; |
1221 | } | |
1222 | ||
1223 | static void blk_tracer_stop(struct trace_array *tr) | |
1224 | { | |
ad5dd549 | 1225 | blk_tracer_enabled = false; |
c71a8961 ACM |
1226 | } |
1227 | ||
1228 | static void blk_tracer_reset(struct trace_array *tr) | |
1229 | { | |
c71a8961 ACM |
1230 | blk_tracer_stop(tr); |
1231 | } | |
1232 | ||
e4955c99 | 1233 | static const struct { |
c71a8961 | 1234 | const char *act[2]; |
ef18012b | 1235 | int (*print)(struct trace_seq *s, const struct trace_entry *ent); |
e4955c99 | 1236 | } what2act[] = { |
ef18012b | 1237 | [__BLK_TA_QUEUE] = {{ "Q", "queue" }, blk_log_generic }, |
c71a8961 ACM |
1238 | [__BLK_TA_BACKMERGE] = {{ "M", "backmerge" }, blk_log_generic }, |
1239 | [__BLK_TA_FRONTMERGE] = {{ "F", "frontmerge" }, blk_log_generic }, | |
1240 | [__BLK_TA_GETRQ] = {{ "G", "getrq" }, blk_log_generic }, | |
1241 | [__BLK_TA_SLEEPRQ] = {{ "S", "sleeprq" }, blk_log_generic }, | |
1242 | [__BLK_TA_REQUEUE] = {{ "R", "requeue" }, blk_log_with_error }, | |
1243 | [__BLK_TA_ISSUE] = {{ "D", "issue" }, blk_log_generic }, | |
1244 | [__BLK_TA_COMPLETE] = {{ "C", "complete" }, blk_log_with_error }, | |
1245 | [__BLK_TA_PLUG] = {{ "P", "plug" }, blk_log_plug }, | |
1246 | [__BLK_TA_UNPLUG_IO] = {{ "U", "unplug_io" }, blk_log_unplug }, | |
1247 | [__BLK_TA_UNPLUG_TIMER] = {{ "UT", "unplug_timer" }, blk_log_unplug }, | |
1248 | [__BLK_TA_INSERT] = {{ "I", "insert" }, blk_log_generic }, | |
1249 | [__BLK_TA_SPLIT] = {{ "X", "split" }, blk_log_split }, | |
1250 | [__BLK_TA_BOUNCE] = {{ "B", "bounce" }, blk_log_generic }, | |
1251 | [__BLK_TA_REMAP] = {{ "A", "remap" }, blk_log_remap }, | |
1252 | }; | |
1253 | ||
b6a4b0c3 LZ |
1254 | static enum print_line_t print_one_line(struct trace_iterator *iter, |
1255 | bool classic) | |
c71a8961 | 1256 | { |
2c9b238e | 1257 | struct trace_seq *s = &iter->seq; |
b6a4b0c3 LZ |
1258 | const struct blk_io_trace *t; |
1259 | u16 what; | |
c71a8961 | 1260 | int ret; |
b6a4b0c3 LZ |
1261 | bool long_act; |
1262 | blk_log_action_t *log_action; | |
c71a8961 | 1263 | |
b6a4b0c3 LZ |
1264 | t = te_blk_io_trace(iter->ent); |
1265 | what = t->action & ((1 << BLK_TC_SHIFT) - 1); | |
1266 | long_act = !!(trace_flags & TRACE_ITER_VERBOSE); | |
1267 | log_action = classic ? &blk_log_action_classic : &blk_log_action; | |
08a06b83 | 1268 | |
18cea459 LZ |
1269 | if (t->action == BLK_TN_MESSAGE) { |
1270 | ret = log_action(iter, long_act ? "message" : "m"); | |
1271 | if (ret) | |
1272 | ret = blk_log_msg(s, iter->ent); | |
1273 | goto out; | |
1274 | } | |
1275 | ||
eb08f8eb | 1276 | if (unlikely(what == 0 || what >= ARRAY_SIZE(what2act))) |
b78825d6 | 1277 | ret = trace_seq_printf(s, "Unknown action %x\n", what); |
c71a8961 | 1278 | else { |
b6a4b0c3 | 1279 | ret = log_action(iter, what2act[what].act[long_act]); |
c71a8961 | 1280 | if (ret) |
2c9b238e | 1281 | ret = what2act[what].print(s, iter->ent); |
c71a8961 | 1282 | } |
18cea459 | 1283 | out: |
c71a8961 ACM |
1284 | return ret ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; |
1285 | } | |
1286 | ||
b6a4b0c3 LZ |
1287 | static enum print_line_t blk_trace_event_print(struct trace_iterator *iter, |
1288 | int flags) | |
1289 | { | |
b6a4b0c3 LZ |
1290 | return print_one_line(iter, false); |
1291 | } | |
1292 | ||
08a06b83 ACM |
1293 | static int blk_trace_synthesize_old_trace(struct trace_iterator *iter) |
1294 | { | |
1295 | struct trace_seq *s = &iter->seq; | |
1296 | struct blk_io_trace *t = (struct blk_io_trace *)iter->ent; | |
1297 | const int offset = offsetof(struct blk_io_trace, sector); | |
1298 | struct blk_io_trace old = { | |
1299 | .magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION, | |
6c051ce0 | 1300 | .time = iter->ts, |
08a06b83 ACM |
1301 | }; |
1302 | ||
1303 | if (!trace_seq_putmem(s, &old, offset)) | |
1304 | return 0; | |
1305 | return trace_seq_putmem(s, &t->sector, | |
1306 | sizeof(old) - offset + t->pdu_len); | |
1307 | } | |
1308 | ||
ae7462b4 ACM |
1309 | static enum print_line_t |
1310 | blk_trace_event_print_binary(struct trace_iterator *iter, int flags) | |
08a06b83 ACM |
1311 | { |
1312 | return blk_trace_synthesize_old_trace(iter) ? | |
1313 | TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; | |
1314 | } | |
1315 | ||
c71a8961 ACM |
1316 | static enum print_line_t blk_tracer_print_line(struct trace_iterator *iter) |
1317 | { | |
c71a8961 ACM |
1318 | if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) |
1319 | return TRACE_TYPE_UNHANDLED; | |
1320 | ||
b6a4b0c3 | 1321 | return print_one_line(iter, true); |
c71a8961 ACM |
1322 | } |
1323 | ||
f3948f88 LZ |
1324 | static int blk_tracer_set_flag(u32 old_flags, u32 bit, int set) |
1325 | { | |
1326 | /* don't output context-info for blk_classic output */ | |
1327 | if (bit == TRACE_BLK_OPT_CLASSIC) { | |
1328 | if (set) | |
1329 | trace_flags &= ~TRACE_ITER_CONTEXT_INFO; | |
1330 | else | |
1331 | trace_flags |= TRACE_ITER_CONTEXT_INFO; | |
1332 | } | |
1333 | return 0; | |
1334 | } | |
1335 | ||
c71a8961 ACM |
1336 | static struct tracer blk_tracer __read_mostly = { |
1337 | .name = "blk", | |
1338 | .init = blk_tracer_init, | |
1339 | .reset = blk_tracer_reset, | |
1340 | .start = blk_tracer_start, | |
1341 | .stop = blk_tracer_stop, | |
1342 | .print_header = blk_tracer_print_header, | |
1343 | .print_line = blk_tracer_print_line, | |
1344 | .flags = &blk_tracer_flags, | |
f3948f88 | 1345 | .set_flag = blk_tracer_set_flag, |
c71a8961 ACM |
1346 | }; |
1347 | ||
1348 | static struct trace_event trace_blk_event = { | |
ef18012b | 1349 | .type = TRACE_BLK, |
c71a8961 | 1350 | .trace = blk_trace_event_print, |
08a06b83 | 1351 | .binary = blk_trace_event_print_binary, |
c71a8961 ACM |
1352 | }; |
1353 | ||
1354 | static int __init init_blk_tracer(void) | |
1355 | { | |
1356 | if (!register_ftrace_event(&trace_blk_event)) { | |
1357 | pr_warning("Warning: could not register block events\n"); | |
1358 | return 1; | |
1359 | } | |
1360 | ||
1361 | if (register_tracer(&blk_tracer) != 0) { | |
1362 | pr_warning("Warning: could not register the block tracer\n"); | |
1363 | unregister_ftrace_event(&trace_blk_event); | |
1364 | return 1; | |
1365 | } | |
1366 | ||
1367 | return 0; | |
1368 | } | |
1369 | ||
1370 | device_initcall(init_blk_tracer); | |
1371 | ||
1372 | static int blk_trace_remove_queue(struct request_queue *q) | |
1373 | { | |
1374 | struct blk_trace *bt; | |
1375 | ||
1376 | bt = xchg(&q->blk_trace, NULL); | |
1377 | if (bt == NULL) | |
1378 | return -EINVAL; | |
1379 | ||
17ba97e3 LZ |
1380 | if (atomic_dec_and_test(&blk_probes_ref)) |
1381 | blk_unregister_tracepoints(); | |
1382 | ||
ad5dd549 | 1383 | blk_trace_free(bt); |
c71a8961 ACM |
1384 | return 0; |
1385 | } | |
1386 | ||
1387 | /* | |
1388 | * Setup everything required to start tracing | |
1389 | */ | |
9908c309 LZ |
1390 | static int blk_trace_setup_queue(struct request_queue *q, |
1391 | struct block_device *bdev) | |
c71a8961 ACM |
1392 | { |
1393 | struct blk_trace *old_bt, *bt = NULL; | |
18cea459 | 1394 | int ret = -ENOMEM; |
c71a8961 | 1395 | |
c71a8961 ACM |
1396 | bt = kzalloc(sizeof(*bt), GFP_KERNEL); |
1397 | if (!bt) | |
15152e44 | 1398 | return -ENOMEM; |
c71a8961 | 1399 | |
18cea459 LZ |
1400 | bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); |
1401 | if (!bt->msg_data) | |
1402 | goto free_bt; | |
1403 | ||
9908c309 | 1404 | bt->dev = bdev->bd_dev; |
c71a8961 | 1405 | bt->act_mask = (u16)-1; |
9908c309 LZ |
1406 | |
1407 | blk_trace_setup_lba(bt, bdev); | |
c71a8961 ACM |
1408 | |
1409 | old_bt = xchg(&q->blk_trace, bt); | |
1410 | if (old_bt != NULL) { | |
1411 | (void)xchg(&q->blk_trace, old_bt); | |
18cea459 LZ |
1412 | ret = -EBUSY; |
1413 | goto free_bt; | |
c71a8961 | 1414 | } |
15152e44 | 1415 | |
17ba97e3 LZ |
1416 | if (atomic_inc_return(&blk_probes_ref) == 1) |
1417 | blk_register_tracepoints(); | |
c71a8961 | 1418 | return 0; |
18cea459 LZ |
1419 | |
1420 | free_bt: | |
1421 | blk_trace_free(bt); | |
1422 | return ret; | |
c71a8961 ACM |
1423 | } |
1424 | ||
1425 | /* | |
1426 | * sysfs interface to enable and configure tracing | |
1427 | */ | |
1428 | ||
c71a8961 ACM |
1429 | static ssize_t sysfs_blk_trace_attr_show(struct device *dev, |
1430 | struct device_attribute *attr, | |
1431 | char *buf); | |
1432 | static ssize_t sysfs_blk_trace_attr_store(struct device *dev, | |
1433 | struct device_attribute *attr, | |
1434 | const char *buf, size_t count); | |
1435 | #define BLK_TRACE_DEVICE_ATTR(_name) \ | |
1436 | DEVICE_ATTR(_name, S_IRUGO | S_IWUSR, \ | |
1437 | sysfs_blk_trace_attr_show, \ | |
1438 | sysfs_blk_trace_attr_store) | |
1439 | ||
cd649b8b | 1440 | static BLK_TRACE_DEVICE_ATTR(enable); |
c71a8961 ACM |
1441 | static BLK_TRACE_DEVICE_ATTR(act_mask); |
1442 | static BLK_TRACE_DEVICE_ATTR(pid); | |
1443 | static BLK_TRACE_DEVICE_ATTR(start_lba); | |
1444 | static BLK_TRACE_DEVICE_ATTR(end_lba); | |
1445 | ||
1446 | static struct attribute *blk_trace_attrs[] = { | |
1447 | &dev_attr_enable.attr, | |
1448 | &dev_attr_act_mask.attr, | |
1449 | &dev_attr_pid.attr, | |
1450 | &dev_attr_start_lba.attr, | |
1451 | &dev_attr_end_lba.attr, | |
1452 | NULL | |
1453 | }; | |
1454 | ||
1455 | struct attribute_group blk_trace_attr_group = { | |
1456 | .name = "trace", | |
1457 | .attrs = blk_trace_attrs, | |
1458 | }; | |
1459 | ||
09341997 LZ |
1460 | static const struct { |
1461 | int mask; | |
1462 | const char *str; | |
1463 | } mask_maps[] = { | |
1464 | { BLK_TC_READ, "read" }, | |
1465 | { BLK_TC_WRITE, "write" }, | |
1466 | { BLK_TC_BARRIER, "barrier" }, | |
1467 | { BLK_TC_SYNC, "sync" }, | |
1468 | { BLK_TC_QUEUE, "queue" }, | |
1469 | { BLK_TC_REQUEUE, "requeue" }, | |
1470 | { BLK_TC_ISSUE, "issue" }, | |
1471 | { BLK_TC_COMPLETE, "complete" }, | |
1472 | { BLK_TC_FS, "fs" }, | |
1473 | { BLK_TC_PC, "pc" }, | |
1474 | { BLK_TC_AHEAD, "ahead" }, | |
1475 | { BLK_TC_META, "meta" }, | |
1476 | { BLK_TC_DISCARD, "discard" }, | |
1477 | { BLK_TC_DRV_DATA, "drv_data" }, | |
1478 | }; | |
1479 | ||
1480 | static int blk_trace_str2mask(const char *str) | |
c71a8961 | 1481 | { |
09341997 | 1482 | int i; |
c71a8961 | 1483 | int mask = 0; |
9eb85125 | 1484 | char *buf, *s, *token; |
c71a8961 | 1485 | |
9eb85125 LZ |
1486 | buf = kstrdup(str, GFP_KERNEL); |
1487 | if (buf == NULL) | |
c71a8961 | 1488 | return -ENOMEM; |
9eb85125 | 1489 | s = strstrip(buf); |
c71a8961 ACM |
1490 | |
1491 | while (1) { | |
09341997 LZ |
1492 | token = strsep(&s, ","); |
1493 | if (token == NULL) | |
c71a8961 ACM |
1494 | break; |
1495 | ||
09341997 LZ |
1496 | if (*token == '\0') |
1497 | continue; | |
1498 | ||
1499 | for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { | |
1500 | if (strcasecmp(token, mask_maps[i].str) == 0) { | |
1501 | mask |= mask_maps[i].mask; | |
1502 | break; | |
1503 | } | |
1504 | } | |
1505 | if (i == ARRAY_SIZE(mask_maps)) { | |
1506 | mask = -EINVAL; | |
1507 | break; | |
1508 | } | |
c71a8961 | 1509 | } |
9eb85125 | 1510 | kfree(buf); |
c71a8961 ACM |
1511 | |
1512 | return mask; | |
1513 | } | |
1514 | ||
09341997 LZ |
1515 | static ssize_t blk_trace_mask2str(char *buf, int mask) |
1516 | { | |
1517 | int i; | |
1518 | char *p = buf; | |
1519 | ||
1520 | for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { | |
1521 | if (mask & mask_maps[i].mask) { | |
1522 | p += sprintf(p, "%s%s", | |
1523 | (p == buf) ? "" : ",", mask_maps[i].str); | |
1524 | } | |
1525 | } | |
1526 | *p++ = '\n'; | |
1527 | ||
1528 | return p - buf; | |
1529 | } | |
1530 | ||
b125130b LZ |
1531 | static struct request_queue *blk_trace_get_queue(struct block_device *bdev) |
1532 | { | |
1533 | if (bdev->bd_disk == NULL) | |
1534 | return NULL; | |
1535 | ||
1536 | return bdev_get_queue(bdev); | |
1537 | } | |
1538 | ||
c71a8961 ACM |
1539 | static ssize_t sysfs_blk_trace_attr_show(struct device *dev, |
1540 | struct device_attribute *attr, | |
1541 | char *buf) | |
1542 | { | |
1543 | struct hd_struct *p = dev_to_part(dev); | |
1544 | struct request_queue *q; | |
1545 | struct block_device *bdev; | |
1546 | ssize_t ret = -ENXIO; | |
1547 | ||
1548 | lock_kernel(); | |
1549 | bdev = bdget(part_devt(p)); | |
1550 | if (bdev == NULL) | |
1551 | goto out_unlock_kernel; | |
1552 | ||
b125130b | 1553 | q = blk_trace_get_queue(bdev); |
c71a8961 ACM |
1554 | if (q == NULL) |
1555 | goto out_bdput; | |
b125130b | 1556 | |
c71a8961 | 1557 | mutex_lock(&bdev->bd_mutex); |
cd649b8b LZ |
1558 | |
1559 | if (attr == &dev_attr_enable) { | |
1560 | ret = sprintf(buf, "%u\n", !!q->blk_trace); | |
1561 | goto out_unlock_bdev; | |
1562 | } | |
1563 | ||
c71a8961 ACM |
1564 | if (q->blk_trace == NULL) |
1565 | ret = sprintf(buf, "disabled\n"); | |
1566 | else if (attr == &dev_attr_act_mask) | |
09341997 | 1567 | ret = blk_trace_mask2str(buf, q->blk_trace->act_mask); |
c71a8961 ACM |
1568 | else if (attr == &dev_attr_pid) |
1569 | ret = sprintf(buf, "%u\n", q->blk_trace->pid); | |
1570 | else if (attr == &dev_attr_start_lba) | |
1571 | ret = sprintf(buf, "%llu\n", q->blk_trace->start_lba); | |
1572 | else if (attr == &dev_attr_end_lba) | |
1573 | ret = sprintf(buf, "%llu\n", q->blk_trace->end_lba); | |
cd649b8b LZ |
1574 | |
1575 | out_unlock_bdev: | |
c71a8961 ACM |
1576 | mutex_unlock(&bdev->bd_mutex); |
1577 | out_bdput: | |
1578 | bdput(bdev); | |
1579 | out_unlock_kernel: | |
1580 | unlock_kernel(); | |
1581 | return ret; | |
1582 | } | |
1583 | ||
1584 | static ssize_t sysfs_blk_trace_attr_store(struct device *dev, | |
1585 | struct device_attribute *attr, | |
1586 | const char *buf, size_t count) | |
1587 | { | |
1588 | struct block_device *bdev; | |
1589 | struct request_queue *q; | |
1590 | struct hd_struct *p; | |
1591 | u64 value; | |
09341997 | 1592 | ssize_t ret = -EINVAL; |
c71a8961 ACM |
1593 | |
1594 | if (count == 0) | |
1595 | goto out; | |
1596 | ||
1597 | if (attr == &dev_attr_act_mask) { | |
1598 | if (sscanf(buf, "%llx", &value) != 1) { | |
1599 | /* Assume it is a list of trace category names */ | |
09341997 LZ |
1600 | ret = blk_trace_str2mask(buf); |
1601 | if (ret < 0) | |
c71a8961 | 1602 | goto out; |
09341997 | 1603 | value = ret; |
c71a8961 ACM |
1604 | } |
1605 | } else if (sscanf(buf, "%llu", &value) != 1) | |
1606 | goto out; | |
1607 | ||
09341997 LZ |
1608 | ret = -ENXIO; |
1609 | ||
c71a8961 ACM |
1610 | lock_kernel(); |
1611 | p = dev_to_part(dev); | |
1612 | bdev = bdget(part_devt(p)); | |
1613 | if (bdev == NULL) | |
1614 | goto out_unlock_kernel; | |
1615 | ||
b125130b | 1616 | q = blk_trace_get_queue(bdev); |
c71a8961 ACM |
1617 | if (q == NULL) |
1618 | goto out_bdput; | |
1619 | ||
1620 | mutex_lock(&bdev->bd_mutex); | |
cd649b8b LZ |
1621 | |
1622 | if (attr == &dev_attr_enable) { | |
1623 | if (value) | |
9908c309 | 1624 | ret = blk_trace_setup_queue(q, bdev); |
cd649b8b LZ |
1625 | else |
1626 | ret = blk_trace_remove_queue(q); | |
1627 | goto out_unlock_bdev; | |
1628 | } | |
1629 | ||
c71a8961 ACM |
1630 | ret = 0; |
1631 | if (q->blk_trace == NULL) | |
9908c309 | 1632 | ret = blk_trace_setup_queue(q, bdev); |
c71a8961 ACM |
1633 | |
1634 | if (ret == 0) { | |
1635 | if (attr == &dev_attr_act_mask) | |
1636 | q->blk_trace->act_mask = value; | |
1637 | else if (attr == &dev_attr_pid) | |
1638 | q->blk_trace->pid = value; | |
1639 | else if (attr == &dev_attr_start_lba) | |
1640 | q->blk_trace->start_lba = value; | |
1641 | else if (attr == &dev_attr_end_lba) | |
1642 | q->blk_trace->end_lba = value; | |
c71a8961 | 1643 | } |
cd649b8b LZ |
1644 | |
1645 | out_unlock_bdev: | |
c71a8961 ACM |
1646 | mutex_unlock(&bdev->bd_mutex); |
1647 | out_bdput: | |
1648 | bdput(bdev); | |
1649 | out_unlock_kernel: | |
1650 | unlock_kernel(); | |
1651 | out: | |
cd649b8b | 1652 | return ret ? ret : count; |
c71a8961 | 1653 | } |
cd649b8b | 1654 | |
1d54ad6d LZ |
1655 | int blk_trace_init_sysfs(struct device *dev) |
1656 | { | |
1657 | return sysfs_create_group(&dev->kobj, &blk_trace_attr_group); | |
1658 | } | |
1659 | ||
55782138 LZ |
1660 | #endif /* CONFIG_BLK_DEV_IO_TRACE */ |
1661 | ||
1662 | #ifdef CONFIG_EVENT_TRACING | |
1663 | ||
1664 | void blk_dump_cmd(char *buf, struct request *rq) | |
1665 | { | |
1666 | int i, end; | |
1667 | int len = rq->cmd_len; | |
1668 | unsigned char *cmd = rq->cmd; | |
1669 | ||
1670 | if (!blk_pc_request(rq)) { | |
1671 | buf[0] = '\0'; | |
1672 | return; | |
1673 | } | |
1674 | ||
1675 | for (end = len - 1; end >= 0; end--) | |
1676 | if (cmd[end]) | |
1677 | break; | |
1678 | end++; | |
1679 | ||
1680 | for (i = 0; i < len; i++) { | |
1681 | buf += sprintf(buf, "%s%02x", i == 0 ? "" : " ", cmd[i]); | |
1682 | if (i == end && end != len - 1) { | |
1683 | sprintf(buf, " .."); | |
1684 | break; | |
1685 | } | |
1686 | } | |
1687 | } | |
1688 | ||
1689 | void blk_fill_rwbs(char *rwbs, u32 rw, int bytes) | |
1690 | { | |
1691 | int i = 0; | |
1692 | ||
1693 | if (rw & WRITE) | |
1694 | rwbs[i++] = 'W'; | |
1695 | else if (rw & 1 << BIO_RW_DISCARD) | |
1696 | rwbs[i++] = 'D'; | |
1697 | else if (bytes) | |
1698 | rwbs[i++] = 'R'; | |
1699 | else | |
1700 | rwbs[i++] = 'N'; | |
1701 | ||
1702 | if (rw & 1 << BIO_RW_AHEAD) | |
1703 | rwbs[i++] = 'A'; | |
1704 | if (rw & 1 << BIO_RW_BARRIER) | |
1705 | rwbs[i++] = 'B'; | |
1706 | if (rw & 1 << BIO_RW_SYNCIO) | |
1707 | rwbs[i++] = 'S'; | |
1708 | if (rw & 1 << BIO_RW_META) | |
1709 | rwbs[i++] = 'M'; | |
1710 | ||
1711 | rwbs[i] = '\0'; | |
1712 | } | |
1713 | ||
1714 | void blk_fill_rwbs_rq(char *rwbs, struct request *rq) | |
1715 | { | |
1716 | int rw = rq->cmd_flags & 0x03; | |
1717 | int bytes; | |
1718 | ||
1719 | if (blk_discard_rq(rq)) | |
1720 | rw |= (1 << BIO_RW_DISCARD); | |
1721 | ||
c9059598 | 1722 | bytes = blk_rq_bytes(rq); |
55782138 LZ |
1723 | |
1724 | blk_fill_rwbs(rwbs, rw, bytes); | |
1725 | } | |
1726 | ||
1727 | #endif /* CONFIG_EVENT_TRACING */ | |
1728 |