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Commit | Line | Data |
---|---|---|
2056a782 | 1 | /* |
0fe23479 | 2 | * Copyright (C) 2006 Jens Axboe <axboe@kernel.dk> |
2056a782 JA |
3 | * |
4 | * This program is free software; you can redistribute it and/or modify | |
5 | * it under the terms of the GNU General Public License version 2 as | |
6 | * published by the Free Software Foundation. | |
7 | * | |
8 | * This program is distributed in the hope that it will be useful, | |
9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
11 | * GNU General Public License for more details. | |
12 | * | |
13 | * You should have received a copy of the GNU General Public License | |
14 | * along with this program; if not, write to the Free Software | |
15 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
16 | * | |
17 | */ | |
2056a782 JA |
18 | #include <linux/kernel.h> |
19 | #include <linux/blkdev.h> | |
20 | #include <linux/blktrace_api.h> | |
21 | #include <linux/percpu.h> | |
22 | #include <linux/init.h> | |
23 | #include <linux/mutex.h> | |
5a0e3ad6 | 24 | #include <linux/slab.h> |
2056a782 | 25 | #include <linux/debugfs.h> |
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 | |
35ba8f70 | 172 | /* The ilog2() calls fall out because they're constant */ |
939b3669 ACM |
173 | #define MASK_TC_BIT(rw, __name) ((rw & (1 << BIO_RW_ ## __name)) << \ |
174 | (ilog2(BLK_TC_ ## __name) + BLK_TC_SHIFT - BIO_RW_ ## __name)) | |
2056a782 JA |
175 | |
176 | /* | |
177 | * The worker for the various blk_add_trace*() types. Fills out a | |
178 | * blk_io_trace structure and places it in a per-cpu subbuffer. | |
179 | */ | |
5f3ea37c | 180 | static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, |
2056a782 JA |
181 | int rw, u32 what, int error, int pdu_len, void *pdu_data) |
182 | { | |
183 | struct task_struct *tsk = current; | |
c71a8961 | 184 | struct ring_buffer_event *event = NULL; |
e77405ad | 185 | struct ring_buffer *buffer = NULL; |
2056a782 | 186 | struct blk_io_trace *t; |
0a987751 | 187 | unsigned long flags = 0; |
2056a782 JA |
188 | unsigned long *sequence; |
189 | pid_t pid; | |
c71a8961 | 190 | int cpu, pc = 0; |
18cea459 | 191 | bool blk_tracer = blk_tracer_enabled; |
2056a782 | 192 | |
18cea459 | 193 | if (unlikely(bt->trace_state != Blktrace_running && !blk_tracer)) |
2056a782 JA |
194 | return; |
195 | ||
196 | what |= ddir_act[rw & WRITE]; | |
35ba8f70 | 197 | what |= MASK_TC_BIT(rw, BARRIER); |
93dbb393 | 198 | what |= MASK_TC_BIT(rw, SYNCIO); |
35ba8f70 DW |
199 | what |= MASK_TC_BIT(rw, AHEAD); |
200 | what |= MASK_TC_BIT(rw, META); | |
201 | what |= MASK_TC_BIT(rw, DISCARD); | |
2056a782 JA |
202 | |
203 | pid = tsk->pid; | |
d0deef5b | 204 | if (act_log_check(bt, what, sector, pid)) |
2056a782 | 205 | return; |
c71a8961 ACM |
206 | cpu = raw_smp_processor_id(); |
207 | ||
18cea459 | 208 | if (blk_tracer) { |
c71a8961 ACM |
209 | tracing_record_cmdline(current); |
210 | ||
e77405ad | 211 | buffer = blk_tr->buffer; |
51a763dd | 212 | pc = preempt_count(); |
e77405ad | 213 | event = trace_buffer_lock_reserve(buffer, TRACE_BLK, |
51a763dd ACM |
214 | sizeof(*t) + pdu_len, |
215 | 0, pc); | |
c71a8961 ACM |
216 | if (!event) |
217 | return; | |
51a763dd | 218 | t = ring_buffer_event_data(event); |
c71a8961 ACM |
219 | goto record_it; |
220 | } | |
2056a782 JA |
221 | |
222 | /* | |
223 | * A word about the locking here - we disable interrupts to reserve | |
224 | * some space in the relay per-cpu buffer, to prevent an irq | |
14a73f54 | 225 | * from coming in and stepping on our toes. |
2056a782 JA |
226 | */ |
227 | local_irq_save(flags); | |
228 | ||
229 | if (unlikely(tsk->btrace_seq != blktrace_seq)) | |
230 | trace_note_tsk(bt, tsk); | |
231 | ||
232 | t = relay_reserve(bt->rchan, sizeof(*t) + pdu_len); | |
233 | if (t) { | |
2056a782 JA |
234 | sequence = per_cpu_ptr(bt->sequence, cpu); |
235 | ||
236 | t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; | |
237 | t->sequence = ++(*sequence); | |
2997c8c4 | 238 | t->time = ktime_to_ns(ktime_get()); |
c71a8961 | 239 | record_it: |
08a06b83 | 240 | /* |
939b3669 ACM |
241 | * These two are not needed in ftrace as they are in the |
242 | * generic trace_entry, filled by tracing_generic_entry_update, | |
243 | * but for the trace_event->bin() synthesizer benefit we do it | |
244 | * here too. | |
245 | */ | |
246 | t->cpu = cpu; | |
247 | t->pid = pid; | |
08a06b83 | 248 | |
2056a782 JA |
249 | t->sector = sector; |
250 | t->bytes = bytes; | |
251 | t->action = what; | |
2056a782 | 252 | t->device = bt->dev; |
2056a782 JA |
253 | t->error = error; |
254 | t->pdu_len = pdu_len; | |
255 | ||
256 | if (pdu_len) | |
257 | memcpy((void *) t + sizeof(*t), pdu_data, pdu_len); | |
c71a8961 | 258 | |
18cea459 | 259 | if (blk_tracer) { |
e77405ad | 260 | trace_buffer_unlock_commit(buffer, event, 0, pc); |
c71a8961 ACM |
261 | return; |
262 | } | |
2056a782 JA |
263 | } |
264 | ||
265 | local_irq_restore(flags); | |
266 | } | |
267 | ||
2056a782 | 268 | static struct dentry *blk_tree_root; |
11a57153 | 269 | static DEFINE_MUTEX(blk_tree_mutex); |
2056a782 | 270 | |
ad5dd549 | 271 | static void blk_trace_free(struct blk_trace *bt) |
2056a782 | 272 | { |
02c62304 | 273 | debugfs_remove(bt->msg_file); |
2056a782 | 274 | debugfs_remove(bt->dropped_file); |
f48fc4d3 | 275 | relay_close(bt->rchan); |
39cbb602 | 276 | debugfs_remove(bt->dir); |
2056a782 | 277 | free_percpu(bt->sequence); |
64565911 | 278 | free_percpu(bt->msg_data); |
2056a782 | 279 | kfree(bt); |
ad5dd549 LZ |
280 | } |
281 | ||
282 | static void blk_trace_cleanup(struct blk_trace *bt) | |
283 | { | |
284 | blk_trace_free(bt); | |
5f3ea37c ACM |
285 | if (atomic_dec_and_test(&blk_probes_ref)) |
286 | blk_unregister_tracepoints(); | |
2056a782 JA |
287 | } |
288 | ||
6da127ad | 289 | int blk_trace_remove(struct request_queue *q) |
2056a782 JA |
290 | { |
291 | struct blk_trace *bt; | |
292 | ||
293 | bt = xchg(&q->blk_trace, NULL); | |
294 | if (!bt) | |
295 | return -EINVAL; | |
296 | ||
55547204 | 297 | if (bt->trace_state != Blktrace_running) |
2056a782 JA |
298 | blk_trace_cleanup(bt); |
299 | ||
300 | return 0; | |
301 | } | |
6da127ad | 302 | EXPORT_SYMBOL_GPL(blk_trace_remove); |
2056a782 JA |
303 | |
304 | static int blk_dropped_open(struct inode *inode, struct file *filp) | |
305 | { | |
8e18e294 | 306 | filp->private_data = inode->i_private; |
2056a782 JA |
307 | |
308 | return 0; | |
309 | } | |
310 | ||
311 | static ssize_t blk_dropped_read(struct file *filp, char __user *buffer, | |
312 | size_t count, loff_t *ppos) | |
313 | { | |
314 | struct blk_trace *bt = filp->private_data; | |
315 | char buf[16]; | |
316 | ||
317 | snprintf(buf, sizeof(buf), "%u\n", atomic_read(&bt->dropped)); | |
318 | ||
319 | return simple_read_from_buffer(buffer, count, ppos, buf, strlen(buf)); | |
320 | } | |
321 | ||
2b8693c0 | 322 | static const struct file_operations blk_dropped_fops = { |
2056a782 JA |
323 | .owner = THIS_MODULE, |
324 | .open = blk_dropped_open, | |
325 | .read = blk_dropped_read, | |
326 | }; | |
327 | ||
02c62304 AB |
328 | static int blk_msg_open(struct inode *inode, struct file *filp) |
329 | { | |
330 | filp->private_data = inode->i_private; | |
331 | ||
332 | return 0; | |
333 | } | |
334 | ||
335 | static ssize_t blk_msg_write(struct file *filp, const char __user *buffer, | |
336 | size_t count, loff_t *ppos) | |
337 | { | |
338 | char *msg; | |
339 | struct blk_trace *bt; | |
340 | ||
7635b03a | 341 | if (count >= BLK_TN_MAX_MSG) |
02c62304 AB |
342 | return -EINVAL; |
343 | ||
a4b3ada8 | 344 | msg = kmalloc(count + 1, GFP_KERNEL); |
02c62304 AB |
345 | if (msg == NULL) |
346 | return -ENOMEM; | |
347 | ||
348 | if (copy_from_user(msg, buffer, count)) { | |
349 | kfree(msg); | |
350 | return -EFAULT; | |
351 | } | |
352 | ||
a4b3ada8 | 353 | msg[count] = '\0'; |
02c62304 AB |
354 | bt = filp->private_data; |
355 | __trace_note_message(bt, "%s", msg); | |
356 | kfree(msg); | |
357 | ||
358 | return count; | |
359 | } | |
360 | ||
361 | static const struct file_operations blk_msg_fops = { | |
362 | .owner = THIS_MODULE, | |
363 | .open = blk_msg_open, | |
364 | .write = blk_msg_write, | |
365 | }; | |
366 | ||
2056a782 JA |
367 | /* |
368 | * Keep track of how many times we encountered a full subbuffer, to aid | |
369 | * the user space app in telling how many lost events there were. | |
370 | */ | |
371 | static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf, | |
372 | void *prev_subbuf, size_t prev_padding) | |
373 | { | |
374 | struct blk_trace *bt; | |
375 | ||
376 | if (!relay_buf_full(buf)) | |
377 | return 1; | |
378 | ||
379 | bt = buf->chan->private_data; | |
380 | atomic_inc(&bt->dropped); | |
381 | return 0; | |
382 | } | |
383 | ||
384 | static int blk_remove_buf_file_callback(struct dentry *dentry) | |
385 | { | |
386 | debugfs_remove(dentry); | |
f48fc4d3 | 387 | |
2056a782 JA |
388 | return 0; |
389 | } | |
390 | ||
391 | static struct dentry *blk_create_buf_file_callback(const char *filename, | |
392 | struct dentry *parent, | |
393 | int mode, | |
394 | struct rchan_buf *buf, | |
395 | int *is_global) | |
396 | { | |
397 | return debugfs_create_file(filename, mode, parent, buf, | |
398 | &relay_file_operations); | |
399 | } | |
400 | ||
401 | static struct rchan_callbacks blk_relay_callbacks = { | |
402 | .subbuf_start = blk_subbuf_start_callback, | |
403 | .create_buf_file = blk_create_buf_file_callback, | |
404 | .remove_buf_file = blk_remove_buf_file_callback, | |
405 | }; | |
406 | ||
9908c309 LZ |
407 | static void blk_trace_setup_lba(struct blk_trace *bt, |
408 | struct block_device *bdev) | |
409 | { | |
410 | struct hd_struct *part = NULL; | |
411 | ||
412 | if (bdev) | |
413 | part = bdev->bd_part; | |
414 | ||
415 | if (part) { | |
416 | bt->start_lba = part->start_sect; | |
417 | bt->end_lba = part->start_sect + part->nr_sects; | |
418 | } else { | |
419 | bt->start_lba = 0; | |
420 | bt->end_lba = -1ULL; | |
421 | } | |
422 | } | |
423 | ||
2056a782 JA |
424 | /* |
425 | * Setup everything required to start tracing | |
426 | */ | |
6da127ad | 427 | int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, |
d0deef5b SD |
428 | struct block_device *bdev, |
429 | struct blk_user_trace_setup *buts) | |
2056a782 | 430 | { |
2056a782 JA |
431 | struct blk_trace *old_bt, *bt = NULL; |
432 | struct dentry *dir = NULL; | |
2056a782 JA |
433 | int ret, i; |
434 | ||
171044d4 | 435 | if (!buts->buf_size || !buts->buf_nr) |
2056a782 JA |
436 | return -EINVAL; |
437 | ||
0497b345 JA |
438 | strncpy(buts->name, name, BLKTRACE_BDEV_SIZE); |
439 | buts->name[BLKTRACE_BDEV_SIZE - 1] = '\0'; | |
2056a782 JA |
440 | |
441 | /* | |
442 | * some device names have larger paths - convert the slashes | |
443 | * to underscores for this to work as expected | |
444 | */ | |
171044d4 AB |
445 | for (i = 0; i < strlen(buts->name); i++) |
446 | if (buts->name[i] == '/') | |
447 | buts->name[i] = '_'; | |
2056a782 | 448 | |
2056a782 JA |
449 | bt = kzalloc(sizeof(*bt), GFP_KERNEL); |
450 | if (!bt) | |
ad5dd549 | 451 | return -ENOMEM; |
2056a782 | 452 | |
ad5dd549 | 453 | ret = -ENOMEM; |
2056a782 JA |
454 | bt->sequence = alloc_percpu(unsigned long); |
455 | if (!bt->sequence) | |
456 | goto err; | |
457 | ||
313e458f | 458 | bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); |
64565911 JA |
459 | if (!bt->msg_data) |
460 | goto err; | |
461 | ||
2056a782 | 462 | ret = -ENOENT; |
f48fc4d3 | 463 | |
b5230b56 | 464 | mutex_lock(&blk_tree_mutex); |
f48fc4d3 JA |
465 | if (!blk_tree_root) { |
466 | blk_tree_root = debugfs_create_dir("block", NULL); | |
b5230b56 LZ |
467 | if (!blk_tree_root) { |
468 | mutex_unlock(&blk_tree_mutex); | |
1a17662e | 469 | goto err; |
b5230b56 | 470 | } |
f48fc4d3 | 471 | } |
b5230b56 | 472 | mutex_unlock(&blk_tree_mutex); |
f48fc4d3 JA |
473 | |
474 | dir = debugfs_create_dir(buts->name, blk_tree_root); | |
475 | ||
2056a782 JA |
476 | if (!dir) |
477 | goto err; | |
478 | ||
479 | bt->dir = dir; | |
6da127ad | 480 | bt->dev = dev; |
2056a782 JA |
481 | atomic_set(&bt->dropped, 0); |
482 | ||
483 | ret = -EIO; | |
939b3669 ACM |
484 | bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt, |
485 | &blk_dropped_fops); | |
2056a782 JA |
486 | if (!bt->dropped_file) |
487 | goto err; | |
488 | ||
02c62304 AB |
489 | bt->msg_file = debugfs_create_file("msg", 0222, dir, bt, &blk_msg_fops); |
490 | if (!bt->msg_file) | |
491 | goto err; | |
492 | ||
171044d4 AB |
493 | bt->rchan = relay_open("trace", dir, buts->buf_size, |
494 | buts->buf_nr, &blk_relay_callbacks, bt); | |
2056a782 JA |
495 | if (!bt->rchan) |
496 | goto err; | |
2056a782 | 497 | |
171044d4 | 498 | bt->act_mask = buts->act_mask; |
2056a782 JA |
499 | if (!bt->act_mask) |
500 | bt->act_mask = (u16) -1; | |
501 | ||
9908c309 | 502 | blk_trace_setup_lba(bt, bdev); |
2056a782 | 503 | |
d0deef5b SD |
504 | /* overwrite with user settings */ |
505 | if (buts->start_lba) | |
506 | bt->start_lba = buts->start_lba; | |
507 | if (buts->end_lba) | |
508 | bt->end_lba = buts->end_lba; | |
509 | ||
171044d4 | 510 | bt->pid = buts->pid; |
2056a782 JA |
511 | bt->trace_state = Blktrace_setup; |
512 | ||
513 | ret = -EBUSY; | |
514 | old_bt = xchg(&q->blk_trace, bt); | |
515 | if (old_bt) { | |
516 | (void) xchg(&q->blk_trace, old_bt); | |
517 | goto err; | |
518 | } | |
519 | ||
17ba97e3 | 520 | if (atomic_inc_return(&blk_probes_ref) == 1) |
cbe28296 LZ |
521 | blk_register_tracepoints(); |
522 | ||
2056a782 JA |
523 | return 0; |
524 | err: | |
ad5dd549 | 525 | blk_trace_free(bt); |
2056a782 JA |
526 | return ret; |
527 | } | |
171044d4 | 528 | |
6da127ad | 529 | int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, |
d0deef5b | 530 | struct block_device *bdev, |
6da127ad | 531 | char __user *arg) |
171044d4 AB |
532 | { |
533 | struct blk_user_trace_setup buts; | |
534 | int ret; | |
535 | ||
536 | ret = copy_from_user(&buts, arg, sizeof(buts)); | |
537 | if (ret) | |
538 | return -EFAULT; | |
539 | ||
d0deef5b | 540 | ret = do_blk_trace_setup(q, name, dev, bdev, &buts); |
171044d4 AB |
541 | if (ret) |
542 | return ret; | |
543 | ||
9a8c28c8 DM |
544 | if (copy_to_user(arg, &buts, sizeof(buts))) { |
545 | blk_trace_remove(q); | |
171044d4 | 546 | return -EFAULT; |
9a8c28c8 | 547 | } |
171044d4 AB |
548 | return 0; |
549 | } | |
6da127ad | 550 | EXPORT_SYMBOL_GPL(blk_trace_setup); |
2056a782 | 551 | |
6da127ad | 552 | int blk_trace_startstop(struct request_queue *q, int start) |
2056a782 | 553 | { |
2056a782 | 554 | int ret; |
939b3669 | 555 | struct blk_trace *bt = q->blk_trace; |
2056a782 | 556 | |
939b3669 | 557 | if (bt == NULL) |
2056a782 JA |
558 | return -EINVAL; |
559 | ||
560 | /* | |
561 | * For starting a trace, we can transition from a setup or stopped | |
562 | * trace. For stopping a trace, the state must be running | |
563 | */ | |
564 | ret = -EINVAL; | |
565 | if (start) { | |
566 | if (bt->trace_state == Blktrace_setup || | |
567 | bt->trace_state == Blktrace_stopped) { | |
568 | blktrace_seq++; | |
569 | smp_mb(); | |
570 | bt->trace_state = Blktrace_running; | |
be1c6341 OK |
571 | |
572 | trace_note_time(bt); | |
2056a782 JA |
573 | ret = 0; |
574 | } | |
575 | } else { | |
576 | if (bt->trace_state == Blktrace_running) { | |
577 | bt->trace_state = Blktrace_stopped; | |
578 | relay_flush(bt->rchan); | |
579 | ret = 0; | |
580 | } | |
581 | } | |
582 | ||
583 | return ret; | |
584 | } | |
6da127ad | 585 | EXPORT_SYMBOL_GPL(blk_trace_startstop); |
2056a782 JA |
586 | |
587 | /** | |
588 | * blk_trace_ioctl: - handle the ioctls associated with tracing | |
589 | * @bdev: the block device | |
ef18012b | 590 | * @cmd: the ioctl cmd |
2056a782 JA |
591 | * @arg: the argument data, if any |
592 | * | |
593 | **/ | |
594 | int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) | |
595 | { | |
165125e1 | 596 | struct request_queue *q; |
2056a782 | 597 | int ret, start = 0; |
6da127ad | 598 | char b[BDEVNAME_SIZE]; |
2056a782 JA |
599 | |
600 | q = bdev_get_queue(bdev); | |
601 | if (!q) | |
602 | return -ENXIO; | |
603 | ||
604 | mutex_lock(&bdev->bd_mutex); | |
605 | ||
606 | switch (cmd) { | |
607 | case BLKTRACESETUP: | |
f36f21ec | 608 | bdevname(bdev, b); |
d0deef5b | 609 | ret = blk_trace_setup(q, b, bdev->bd_dev, bdev, arg); |
2056a782 JA |
610 | break; |
611 | case BLKTRACESTART: | |
612 | start = 1; | |
613 | case BLKTRACESTOP: | |
614 | ret = blk_trace_startstop(q, start); | |
615 | break; | |
616 | case BLKTRACETEARDOWN: | |
617 | ret = blk_trace_remove(q); | |
618 | break; | |
619 | default: | |
620 | ret = -ENOTTY; | |
621 | break; | |
622 | } | |
623 | ||
624 | mutex_unlock(&bdev->bd_mutex); | |
625 | return ret; | |
626 | } | |
627 | ||
628 | /** | |
629 | * blk_trace_shutdown: - stop and cleanup trace structures | |
630 | * @q: the request queue associated with the device | |
631 | * | |
632 | **/ | |
165125e1 | 633 | void blk_trace_shutdown(struct request_queue *q) |
2056a782 | 634 | { |
6c5c9341 AD |
635 | if (q->blk_trace) { |
636 | blk_trace_startstop(q, 0); | |
637 | blk_trace_remove(q); | |
638 | } | |
2056a782 | 639 | } |
5f3ea37c ACM |
640 | |
641 | /* | |
642 | * blktrace probes | |
643 | */ | |
644 | ||
645 | /** | |
646 | * blk_add_trace_rq - Add a trace for a request oriented action | |
647 | * @q: queue the io is for | |
648 | * @rq: the source request | |
649 | * @what: the action | |
650 | * | |
651 | * Description: | |
652 | * Records an action against a request. Will log the bio offset + size. | |
653 | * | |
654 | **/ | |
655 | static void blk_add_trace_rq(struct request_queue *q, struct request *rq, | |
656 | u32 what) | |
657 | { | |
658 | struct blk_trace *bt = q->blk_trace; | |
659 | int rw = rq->cmd_flags & 0x03; | |
660 | ||
661 | if (likely(!bt)) | |
662 | return; | |
663 | ||
664 | if (blk_discard_rq(rq)) | |
665 | rw |= (1 << BIO_RW_DISCARD); | |
666 | ||
667 | if (blk_pc_request(rq)) { | |
668 | what |= BLK_TC_ACT(BLK_TC_PC); | |
2e46e8b2 TH |
669 | __blk_add_trace(bt, 0, blk_rq_bytes(rq), rw, |
670 | what, rq->errors, rq->cmd_len, rq->cmd); | |
5f3ea37c ACM |
671 | } else { |
672 | what |= BLK_TC_ACT(BLK_TC_FS); | |
2e46e8b2 TH |
673 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), rw, |
674 | what, rq->errors, 0, NULL); | |
5f3ea37c ACM |
675 | } |
676 | } | |
677 | ||
38516ab5 SR |
678 | static void blk_add_trace_rq_abort(void *ignore, |
679 | struct request_queue *q, struct request *rq) | |
5f3ea37c ACM |
680 | { |
681 | blk_add_trace_rq(q, rq, BLK_TA_ABORT); | |
682 | } | |
683 | ||
38516ab5 SR |
684 | static void blk_add_trace_rq_insert(void *ignore, |
685 | struct request_queue *q, struct request *rq) | |
5f3ea37c ACM |
686 | { |
687 | blk_add_trace_rq(q, rq, BLK_TA_INSERT); | |
688 | } | |
689 | ||
38516ab5 SR |
690 | static void blk_add_trace_rq_issue(void *ignore, |
691 | struct request_queue *q, struct request *rq) | |
5f3ea37c ACM |
692 | { |
693 | blk_add_trace_rq(q, rq, BLK_TA_ISSUE); | |
694 | } | |
695 | ||
38516ab5 SR |
696 | static void blk_add_trace_rq_requeue(void *ignore, |
697 | struct request_queue *q, | |
939b3669 | 698 | struct request *rq) |
5f3ea37c ACM |
699 | { |
700 | blk_add_trace_rq(q, rq, BLK_TA_REQUEUE); | |
701 | } | |
702 | ||
38516ab5 SR |
703 | static void blk_add_trace_rq_complete(void *ignore, |
704 | struct request_queue *q, | |
939b3669 | 705 | struct request *rq) |
5f3ea37c ACM |
706 | { |
707 | blk_add_trace_rq(q, rq, BLK_TA_COMPLETE); | |
708 | } | |
709 | ||
710 | /** | |
711 | * blk_add_trace_bio - Add a trace for a bio oriented action | |
712 | * @q: queue the io is for | |
713 | * @bio: the source bio | |
714 | * @what: the action | |
715 | * | |
716 | * Description: | |
717 | * Records an action against a bio. Will log the bio offset + size. | |
718 | * | |
719 | **/ | |
720 | static void blk_add_trace_bio(struct request_queue *q, struct bio *bio, | |
721 | u32 what) | |
722 | { | |
723 | struct blk_trace *bt = q->blk_trace; | |
724 | ||
725 | if (likely(!bt)) | |
726 | return; | |
727 | ||
728 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, | |
729 | !bio_flagged(bio, BIO_UPTODATE), 0, NULL); | |
730 | } | |
731 | ||
38516ab5 SR |
732 | static void blk_add_trace_bio_bounce(void *ignore, |
733 | struct request_queue *q, struct bio *bio) | |
5f3ea37c ACM |
734 | { |
735 | blk_add_trace_bio(q, bio, BLK_TA_BOUNCE); | |
736 | } | |
737 | ||
38516ab5 SR |
738 | static void blk_add_trace_bio_complete(void *ignore, |
739 | struct request_queue *q, struct bio *bio) | |
5f3ea37c ACM |
740 | { |
741 | blk_add_trace_bio(q, bio, BLK_TA_COMPLETE); | |
742 | } | |
743 | ||
38516ab5 SR |
744 | static void blk_add_trace_bio_backmerge(void *ignore, |
745 | struct request_queue *q, | |
939b3669 | 746 | struct bio *bio) |
5f3ea37c ACM |
747 | { |
748 | blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE); | |
749 | } | |
750 | ||
38516ab5 SR |
751 | static void blk_add_trace_bio_frontmerge(void *ignore, |
752 | struct request_queue *q, | |
939b3669 | 753 | struct bio *bio) |
5f3ea37c ACM |
754 | { |
755 | blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE); | |
756 | } | |
757 | ||
38516ab5 SR |
758 | static void blk_add_trace_bio_queue(void *ignore, |
759 | struct request_queue *q, struct bio *bio) | |
5f3ea37c ACM |
760 | { |
761 | blk_add_trace_bio(q, bio, BLK_TA_QUEUE); | |
762 | } | |
763 | ||
38516ab5 SR |
764 | static void blk_add_trace_getrq(void *ignore, |
765 | struct request_queue *q, | |
939b3669 | 766 | struct bio *bio, int rw) |
5f3ea37c ACM |
767 | { |
768 | if (bio) | |
769 | blk_add_trace_bio(q, bio, BLK_TA_GETRQ); | |
770 | else { | |
771 | struct blk_trace *bt = q->blk_trace; | |
772 | ||
773 | if (bt) | |
774 | __blk_add_trace(bt, 0, 0, rw, BLK_TA_GETRQ, 0, 0, NULL); | |
775 | } | |
776 | } | |
777 | ||
778 | ||
38516ab5 SR |
779 | static void blk_add_trace_sleeprq(void *ignore, |
780 | struct request_queue *q, | |
939b3669 | 781 | struct bio *bio, int rw) |
5f3ea37c ACM |
782 | { |
783 | if (bio) | |
784 | blk_add_trace_bio(q, bio, BLK_TA_SLEEPRQ); | |
785 | else { | |
786 | struct blk_trace *bt = q->blk_trace; | |
787 | ||
788 | if (bt) | |
939b3669 ACM |
789 | __blk_add_trace(bt, 0, 0, rw, BLK_TA_SLEEPRQ, |
790 | 0, 0, NULL); | |
5f3ea37c ACM |
791 | } |
792 | } | |
793 | ||
38516ab5 | 794 | static void blk_add_trace_plug(void *ignore, struct request_queue *q) |
5f3ea37c ACM |
795 | { |
796 | struct blk_trace *bt = q->blk_trace; | |
797 | ||
798 | if (bt) | |
799 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_PLUG, 0, 0, NULL); | |
800 | } | |
801 | ||
38516ab5 | 802 | static void blk_add_trace_unplug_io(void *ignore, struct request_queue *q) |
5f3ea37c ACM |
803 | { |
804 | struct blk_trace *bt = q->blk_trace; | |
805 | ||
806 | if (bt) { | |
807 | unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; | |
808 | __be64 rpdu = cpu_to_be64(pdu); | |
809 | ||
810 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_IO, 0, | |
811 | sizeof(rpdu), &rpdu); | |
812 | } | |
813 | } | |
814 | ||
38516ab5 | 815 | static void blk_add_trace_unplug_timer(void *ignore, struct request_queue *q) |
5f3ea37c ACM |
816 | { |
817 | struct blk_trace *bt = q->blk_trace; | |
818 | ||
819 | if (bt) { | |
820 | unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; | |
821 | __be64 rpdu = cpu_to_be64(pdu); | |
822 | ||
823 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_TIMER, 0, | |
824 | sizeof(rpdu), &rpdu); | |
825 | } | |
826 | } | |
827 | ||
38516ab5 SR |
828 | static void blk_add_trace_split(void *ignore, |
829 | struct request_queue *q, struct bio *bio, | |
5f3ea37c ACM |
830 | unsigned int pdu) |
831 | { | |
832 | struct blk_trace *bt = q->blk_trace; | |
833 | ||
834 | if (bt) { | |
835 | __be64 rpdu = cpu_to_be64(pdu); | |
836 | ||
837 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, | |
838 | BLK_TA_SPLIT, !bio_flagged(bio, BIO_UPTODATE), | |
839 | sizeof(rpdu), &rpdu); | |
840 | } | |
841 | } | |
842 | ||
843 | /** | |
844 | * blk_add_trace_remap - Add a trace for a remap operation | |
845 | * @q: queue the io is for | |
846 | * @bio: the source bio | |
847 | * @dev: target device | |
a42aaa3b | 848 | * @from: source sector |
5f3ea37c ACM |
849 | * |
850 | * Description: | |
851 | * Device mapper or raid target sometimes need to split a bio because | |
852 | * it spans a stripe (or similar). Add a trace for that action. | |
853 | * | |
854 | **/ | |
38516ab5 SR |
855 | static void blk_add_trace_remap(void *ignore, |
856 | struct request_queue *q, struct bio *bio, | |
857 | dev_t dev, sector_t from) | |
5f3ea37c ACM |
858 | { |
859 | struct blk_trace *bt = q->blk_trace; | |
860 | struct blk_io_trace_remap r; | |
861 | ||
862 | if (likely(!bt)) | |
863 | return; | |
864 | ||
a42aaa3b AB |
865 | r.device_from = cpu_to_be32(dev); |
866 | r.device_to = cpu_to_be32(bio->bi_bdev->bd_dev); | |
867 | r.sector_from = cpu_to_be64(from); | |
5f3ea37c | 868 | |
22a7c31a AB |
869 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, |
870 | BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), | |
871 | sizeof(r), &r); | |
5f3ea37c ACM |
872 | } |
873 | ||
b0da3f0d JN |
874 | /** |
875 | * blk_add_trace_rq_remap - Add a trace for a request-remap operation | |
876 | * @q: queue the io is for | |
877 | * @rq: the source request | |
878 | * @dev: target device | |
879 | * @from: source sector | |
880 | * | |
881 | * Description: | |
882 | * Device mapper remaps request to other devices. | |
883 | * Add a trace for that action. | |
884 | * | |
885 | **/ | |
38516ab5 SR |
886 | static void blk_add_trace_rq_remap(void *ignore, |
887 | struct request_queue *q, | |
b0da3f0d JN |
888 | struct request *rq, dev_t dev, |
889 | sector_t from) | |
890 | { | |
891 | struct blk_trace *bt = q->blk_trace; | |
892 | struct blk_io_trace_remap r; | |
893 | ||
894 | if (likely(!bt)) | |
895 | return; | |
896 | ||
897 | r.device_from = cpu_to_be32(dev); | |
898 | r.device_to = cpu_to_be32(disk_devt(rq->rq_disk)); | |
899 | r.sector_from = cpu_to_be64(from); | |
900 | ||
901 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), | |
902 | rq_data_dir(rq), BLK_TA_REMAP, !!rq->errors, | |
903 | sizeof(r), &r); | |
904 | } | |
905 | ||
5f3ea37c ACM |
906 | /** |
907 | * blk_add_driver_data - Add binary message with driver-specific data | |
908 | * @q: queue the io is for | |
909 | * @rq: io request | |
910 | * @data: driver-specific data | |
911 | * @len: length of driver-specific data | |
912 | * | |
913 | * Description: | |
914 | * Some drivers might want to write driver-specific data per request. | |
915 | * | |
916 | **/ | |
917 | void blk_add_driver_data(struct request_queue *q, | |
918 | struct request *rq, | |
919 | void *data, size_t len) | |
920 | { | |
921 | struct blk_trace *bt = q->blk_trace; | |
922 | ||
923 | if (likely(!bt)) | |
924 | return; | |
925 | ||
926 | if (blk_pc_request(rq)) | |
2e46e8b2 TH |
927 | __blk_add_trace(bt, 0, blk_rq_bytes(rq), 0, |
928 | BLK_TA_DRV_DATA, rq->errors, len, data); | |
5f3ea37c | 929 | else |
2e46e8b2 TH |
930 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), 0, |
931 | BLK_TA_DRV_DATA, rq->errors, len, data); | |
5f3ea37c ACM |
932 | } |
933 | EXPORT_SYMBOL_GPL(blk_add_driver_data); | |
934 | ||
3c289ba7 | 935 | static void blk_register_tracepoints(void) |
5f3ea37c ACM |
936 | { |
937 | int ret; | |
938 | ||
38516ab5 | 939 | ret = register_trace_block_rq_abort(blk_add_trace_rq_abort, NULL); |
5f3ea37c | 940 | WARN_ON(ret); |
38516ab5 | 941 | ret = register_trace_block_rq_insert(blk_add_trace_rq_insert, NULL); |
5f3ea37c | 942 | WARN_ON(ret); |
38516ab5 | 943 | ret = register_trace_block_rq_issue(blk_add_trace_rq_issue, NULL); |
5f3ea37c | 944 | WARN_ON(ret); |
38516ab5 | 945 | ret = register_trace_block_rq_requeue(blk_add_trace_rq_requeue, NULL); |
5f3ea37c | 946 | WARN_ON(ret); |
38516ab5 | 947 | ret = register_trace_block_rq_complete(blk_add_trace_rq_complete, NULL); |
5f3ea37c | 948 | WARN_ON(ret); |
38516ab5 | 949 | ret = register_trace_block_bio_bounce(blk_add_trace_bio_bounce, NULL); |
5f3ea37c | 950 | WARN_ON(ret); |
38516ab5 | 951 | ret = register_trace_block_bio_complete(blk_add_trace_bio_complete, NULL); |
5f3ea37c | 952 | WARN_ON(ret); |
38516ab5 | 953 | ret = register_trace_block_bio_backmerge(blk_add_trace_bio_backmerge, NULL); |
5f3ea37c | 954 | WARN_ON(ret); |
38516ab5 | 955 | ret = register_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge, NULL); |
5f3ea37c | 956 | WARN_ON(ret); |
38516ab5 | 957 | ret = register_trace_block_bio_queue(blk_add_trace_bio_queue, NULL); |
5f3ea37c | 958 | WARN_ON(ret); |
38516ab5 | 959 | ret = register_trace_block_getrq(blk_add_trace_getrq, NULL); |
5f3ea37c | 960 | WARN_ON(ret); |
38516ab5 | 961 | ret = register_trace_block_sleeprq(blk_add_trace_sleeprq, NULL); |
5f3ea37c | 962 | WARN_ON(ret); |
38516ab5 | 963 | ret = register_trace_block_plug(blk_add_trace_plug, NULL); |
5f3ea37c | 964 | WARN_ON(ret); |
38516ab5 | 965 | ret = register_trace_block_unplug_timer(blk_add_trace_unplug_timer, NULL); |
5f3ea37c | 966 | WARN_ON(ret); |
38516ab5 | 967 | ret = register_trace_block_unplug_io(blk_add_trace_unplug_io, NULL); |
5f3ea37c | 968 | WARN_ON(ret); |
38516ab5 | 969 | ret = register_trace_block_split(blk_add_trace_split, NULL); |
5f3ea37c | 970 | WARN_ON(ret); |
38516ab5 | 971 | ret = register_trace_block_remap(blk_add_trace_remap, NULL); |
5f3ea37c | 972 | WARN_ON(ret); |
38516ab5 | 973 | ret = register_trace_block_rq_remap(blk_add_trace_rq_remap, NULL); |
b0da3f0d | 974 | WARN_ON(ret); |
5f3ea37c ACM |
975 | } |
976 | ||
977 | static void blk_unregister_tracepoints(void) | |
978 | { | |
38516ab5 SR |
979 | unregister_trace_block_rq_remap(blk_add_trace_rq_remap, NULL); |
980 | unregister_trace_block_remap(blk_add_trace_remap, NULL); | |
981 | unregister_trace_block_split(blk_add_trace_split, NULL); | |
982 | unregister_trace_block_unplug_io(blk_add_trace_unplug_io, NULL); | |
983 | unregister_trace_block_unplug_timer(blk_add_trace_unplug_timer, NULL); | |
984 | unregister_trace_block_plug(blk_add_trace_plug, NULL); | |
985 | unregister_trace_block_sleeprq(blk_add_trace_sleeprq, NULL); | |
986 | unregister_trace_block_getrq(blk_add_trace_getrq, NULL); | |
987 | unregister_trace_block_bio_queue(blk_add_trace_bio_queue, NULL); | |
988 | unregister_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge, NULL); | |
989 | unregister_trace_block_bio_backmerge(blk_add_trace_bio_backmerge, NULL); | |
990 | unregister_trace_block_bio_complete(blk_add_trace_bio_complete, NULL); | |
991 | unregister_trace_block_bio_bounce(blk_add_trace_bio_bounce, NULL); | |
992 | unregister_trace_block_rq_complete(blk_add_trace_rq_complete, NULL); | |
993 | unregister_trace_block_rq_requeue(blk_add_trace_rq_requeue, NULL); | |
994 | unregister_trace_block_rq_issue(blk_add_trace_rq_issue, NULL); | |
995 | unregister_trace_block_rq_insert(blk_add_trace_rq_insert, NULL); | |
996 | unregister_trace_block_rq_abort(blk_add_trace_rq_abort, NULL); | |
5f3ea37c ACM |
997 | |
998 | tracepoint_synchronize_unregister(); | |
999 | } | |
c71a8961 ACM |
1000 | |
1001 | /* | |
1002 | * struct blk_io_tracer formatting routines | |
1003 | */ | |
1004 | ||
1005 | static void fill_rwbs(char *rwbs, const struct blk_io_trace *t) | |
1006 | { | |
157f9c00 | 1007 | int i = 0; |
65796348 | 1008 | int tc = t->action >> BLK_TC_SHIFT; |
157f9c00 | 1009 | |
18cea459 LZ |
1010 | if (t->action == BLK_TN_MESSAGE) { |
1011 | rwbs[i++] = 'N'; | |
1012 | goto out; | |
1013 | } | |
1014 | ||
65796348 | 1015 | if (tc & BLK_TC_DISCARD) |
157f9c00 | 1016 | rwbs[i++] = 'D'; |
65796348 | 1017 | else if (tc & BLK_TC_WRITE) |
157f9c00 ACM |
1018 | rwbs[i++] = 'W'; |
1019 | else if (t->bytes) | |
1020 | rwbs[i++] = 'R'; | |
1021 | else | |
1022 | rwbs[i++] = 'N'; | |
1023 | ||
65796348 | 1024 | if (tc & BLK_TC_AHEAD) |
157f9c00 | 1025 | rwbs[i++] = 'A'; |
65796348 | 1026 | if (tc & BLK_TC_BARRIER) |
157f9c00 | 1027 | rwbs[i++] = 'B'; |
65796348 | 1028 | if (tc & BLK_TC_SYNC) |
157f9c00 | 1029 | rwbs[i++] = 'S'; |
65796348 | 1030 | if (tc & BLK_TC_META) |
157f9c00 | 1031 | rwbs[i++] = 'M'; |
18cea459 | 1032 | out: |
157f9c00 | 1033 | rwbs[i] = '\0'; |
c71a8961 ACM |
1034 | } |
1035 | ||
1036 | static inline | |
1037 | const struct blk_io_trace *te_blk_io_trace(const struct trace_entry *ent) | |
1038 | { | |
1039 | return (const struct blk_io_trace *)ent; | |
1040 | } | |
1041 | ||
1042 | static inline const void *pdu_start(const struct trace_entry *ent) | |
1043 | { | |
1044 | return te_blk_io_trace(ent) + 1; | |
1045 | } | |
1046 | ||
66de7792 LZ |
1047 | static inline u32 t_action(const struct trace_entry *ent) |
1048 | { | |
1049 | return te_blk_io_trace(ent)->action; | |
1050 | } | |
1051 | ||
1052 | static inline u32 t_bytes(const struct trace_entry *ent) | |
1053 | { | |
1054 | return te_blk_io_trace(ent)->bytes; | |
1055 | } | |
1056 | ||
c71a8961 ACM |
1057 | static inline u32 t_sec(const struct trace_entry *ent) |
1058 | { | |
1059 | return te_blk_io_trace(ent)->bytes >> 9; | |
1060 | } | |
1061 | ||
1062 | static inline unsigned long long t_sector(const struct trace_entry *ent) | |
1063 | { | |
1064 | return te_blk_io_trace(ent)->sector; | |
1065 | } | |
1066 | ||
1067 | static inline __u16 t_error(const struct trace_entry *ent) | |
1068 | { | |
e0dc81be | 1069 | return te_blk_io_trace(ent)->error; |
c71a8961 ACM |
1070 | } |
1071 | ||
1072 | static __u64 get_pdu_int(const struct trace_entry *ent) | |
1073 | { | |
1074 | const __u64 *val = pdu_start(ent); | |
1075 | return be64_to_cpu(*val); | |
1076 | } | |
1077 | ||
1078 | static void get_pdu_remap(const struct trace_entry *ent, | |
1079 | struct blk_io_trace_remap *r) | |
1080 | { | |
1081 | const struct blk_io_trace_remap *__r = pdu_start(ent); | |
a42aaa3b | 1082 | __u64 sector_from = __r->sector_from; |
c71a8961 | 1083 | |
c71a8961 | 1084 | r->device_from = be32_to_cpu(__r->device_from); |
a42aaa3b AB |
1085 | r->device_to = be32_to_cpu(__r->device_to); |
1086 | r->sector_from = be64_to_cpu(sector_from); | |
c71a8961 ACM |
1087 | } |
1088 | ||
b6a4b0c3 LZ |
1089 | typedef int (blk_log_action_t) (struct trace_iterator *iter, const char *act); |
1090 | ||
1091 | static int blk_log_action_classic(struct trace_iterator *iter, const char *act) | |
c71a8961 ACM |
1092 | { |
1093 | char rwbs[6]; | |
35ac51bf LZ |
1094 | unsigned long long ts = iter->ts; |
1095 | unsigned long nsec_rem = do_div(ts, NSEC_PER_SEC); | |
c71a8961 | 1096 | unsigned secs = (unsigned long)ts; |
b6a4b0c3 | 1097 | const struct blk_io_trace *t = te_blk_io_trace(iter->ent); |
c71a8961 ACM |
1098 | |
1099 | fill_rwbs(rwbs, t); | |
1100 | ||
1101 | return trace_seq_printf(&iter->seq, | |
35ac51bf | 1102 | "%3d,%-3d %2d %5d.%09lu %5u %2s %3s ", |
c71a8961 | 1103 | MAJOR(t->device), MINOR(t->device), iter->cpu, |
b6a4b0c3 | 1104 | secs, nsec_rem, iter->ent->pid, act, rwbs); |
c71a8961 ACM |
1105 | } |
1106 | ||
b6a4b0c3 | 1107 | static int blk_log_action(struct trace_iterator *iter, const char *act) |
c71a8961 ACM |
1108 | { |
1109 | char rwbs[6]; | |
b6a4b0c3 LZ |
1110 | const struct blk_io_trace *t = te_blk_io_trace(iter->ent); |
1111 | ||
c71a8961 | 1112 | fill_rwbs(rwbs, t); |
b6a4b0c3 | 1113 | return trace_seq_printf(&iter->seq, "%3d,%-3d %2s %3s ", |
c71a8961 ACM |
1114 | MAJOR(t->device), MINOR(t->device), act, rwbs); |
1115 | } | |
1116 | ||
66de7792 LZ |
1117 | static int blk_log_dump_pdu(struct trace_seq *s, const struct trace_entry *ent) |
1118 | { | |
04986257 | 1119 | const unsigned char *pdu_buf; |
66de7792 LZ |
1120 | int pdu_len; |
1121 | int i, end, ret; | |
1122 | ||
1123 | pdu_buf = pdu_start(ent); | |
1124 | pdu_len = te_blk_io_trace(ent)->pdu_len; | |
1125 | ||
1126 | if (!pdu_len) | |
1127 | return 1; | |
1128 | ||
1129 | /* find the last zero that needs to be printed */ | |
1130 | for (end = pdu_len - 1; end >= 0; end--) | |
1131 | if (pdu_buf[end]) | |
1132 | break; | |
1133 | end++; | |
1134 | ||
1135 | if (!trace_seq_putc(s, '(')) | |
1136 | return 0; | |
1137 | ||
1138 | for (i = 0; i < pdu_len; i++) { | |
1139 | ||
1140 | ret = trace_seq_printf(s, "%s%02x", | |
1141 | i == 0 ? "" : " ", pdu_buf[i]); | |
1142 | if (!ret) | |
1143 | return ret; | |
1144 | ||
1145 | /* | |
1146 | * stop when the rest is just zeroes and indicate so | |
1147 | * with a ".." appended | |
1148 | */ | |
1149 | if (i == end && end != pdu_len - 1) | |
1150 | return trace_seq_puts(s, " ..) "); | |
1151 | } | |
1152 | ||
1153 | return trace_seq_puts(s, ") "); | |
1154 | } | |
1155 | ||
c71a8961 ACM |
1156 | static int blk_log_generic(struct trace_seq *s, const struct trace_entry *ent) |
1157 | { | |
4ca53085 SR |
1158 | char cmd[TASK_COMM_LEN]; |
1159 | ||
1160 | trace_find_cmdline(ent->pid, cmd); | |
c71a8961 | 1161 | |
66de7792 LZ |
1162 | if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { |
1163 | int ret; | |
1164 | ||
1165 | ret = trace_seq_printf(s, "%u ", t_bytes(ent)); | |
1166 | if (!ret) | |
1167 | return 0; | |
1168 | ret = blk_log_dump_pdu(s, ent); | |
1169 | if (!ret) | |
1170 | return 0; | |
1171 | return trace_seq_printf(s, "[%s]\n", cmd); | |
1172 | } else { | |
1173 | if (t_sec(ent)) | |
1174 | return trace_seq_printf(s, "%llu + %u [%s]\n", | |
1175 | t_sector(ent), t_sec(ent), cmd); | |
1176 | return trace_seq_printf(s, "[%s]\n", cmd); | |
1177 | } | |
c71a8961 ACM |
1178 | } |
1179 | ||
157f9c00 ACM |
1180 | static int blk_log_with_error(struct trace_seq *s, |
1181 | const struct trace_entry *ent) | |
c71a8961 | 1182 | { |
66de7792 LZ |
1183 | if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { |
1184 | int ret; | |
1185 | ||
1186 | ret = blk_log_dump_pdu(s, ent); | |
1187 | if (ret) | |
1188 | return trace_seq_printf(s, "[%d]\n", t_error(ent)); | |
1189 | return 0; | |
1190 | } else { | |
1191 | if (t_sec(ent)) | |
1192 | return trace_seq_printf(s, "%llu + %u [%d]\n", | |
1193 | t_sector(ent), | |
1194 | t_sec(ent), t_error(ent)); | |
1195 | return trace_seq_printf(s, "%llu [%d]\n", | |
1196 | t_sector(ent), t_error(ent)); | |
1197 | } | |
c71a8961 ACM |
1198 | } |
1199 | ||
1200 | static int blk_log_remap(struct trace_seq *s, const struct trace_entry *ent) | |
1201 | { | |
a42aaa3b | 1202 | struct blk_io_trace_remap r = { .device_from = 0, }; |
c71a8961 ACM |
1203 | |
1204 | get_pdu_remap(ent, &r); | |
1205 | return trace_seq_printf(s, "%llu + %u <- (%d,%d) %llu\n", | |
a42aaa3b AB |
1206 | t_sector(ent), t_sec(ent), |
1207 | MAJOR(r.device_from), MINOR(r.device_from), | |
1208 | (unsigned long long)r.sector_from); | |
c71a8961 ACM |
1209 | } |
1210 | ||
1211 | static int blk_log_plug(struct trace_seq *s, const struct trace_entry *ent) | |
1212 | { | |
4ca53085 SR |
1213 | char cmd[TASK_COMM_LEN]; |
1214 | ||
1215 | trace_find_cmdline(ent->pid, cmd); | |
1216 | ||
1217 | return trace_seq_printf(s, "[%s]\n", cmd); | |
c71a8961 ACM |
1218 | } |
1219 | ||
1220 | static int blk_log_unplug(struct trace_seq *s, const struct trace_entry *ent) | |
1221 | { | |
4ca53085 SR |
1222 | char cmd[TASK_COMM_LEN]; |
1223 | ||
1224 | trace_find_cmdline(ent->pid, cmd); | |
1225 | ||
1226 | return trace_seq_printf(s, "[%s] %llu\n", cmd, get_pdu_int(ent)); | |
c71a8961 ACM |
1227 | } |
1228 | ||
1229 | static int blk_log_split(struct trace_seq *s, const struct trace_entry *ent) | |
1230 | { | |
4ca53085 SR |
1231 | char cmd[TASK_COMM_LEN]; |
1232 | ||
1233 | trace_find_cmdline(ent->pid, cmd); | |
1234 | ||
c71a8961 | 1235 | return trace_seq_printf(s, "%llu / %llu [%s]\n", t_sector(ent), |
4ca53085 | 1236 | get_pdu_int(ent), cmd); |
c71a8961 ACM |
1237 | } |
1238 | ||
18cea459 LZ |
1239 | static int blk_log_msg(struct trace_seq *s, const struct trace_entry *ent) |
1240 | { | |
1241 | int ret; | |
1242 | const struct blk_io_trace *t = te_blk_io_trace(ent); | |
1243 | ||
1244 | ret = trace_seq_putmem(s, t + 1, t->pdu_len); | |
1245 | if (ret) | |
1246 | return trace_seq_putc(s, '\n'); | |
1247 | return ret; | |
1248 | } | |
1249 | ||
c71a8961 ACM |
1250 | /* |
1251 | * struct tracer operations | |
1252 | */ | |
1253 | ||
1254 | static void blk_tracer_print_header(struct seq_file *m) | |
1255 | { | |
1256 | if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) | |
1257 | return; | |
1258 | seq_puts(m, "# DEV CPU TIMESTAMP PID ACT FLG\n" | |
1259 | "# | | | | | |\n"); | |
1260 | } | |
1261 | ||
1262 | static void blk_tracer_start(struct trace_array *tr) | |
1263 | { | |
ad5dd549 | 1264 | blk_tracer_enabled = true; |
c71a8961 ACM |
1265 | } |
1266 | ||
1267 | static int blk_tracer_init(struct trace_array *tr) | |
1268 | { | |
1269 | blk_tr = tr; | |
1270 | blk_tracer_start(tr); | |
c71a8961 ACM |
1271 | return 0; |
1272 | } | |
1273 | ||
1274 | static void blk_tracer_stop(struct trace_array *tr) | |
1275 | { | |
ad5dd549 | 1276 | blk_tracer_enabled = false; |
c71a8961 ACM |
1277 | } |
1278 | ||
1279 | static void blk_tracer_reset(struct trace_array *tr) | |
1280 | { | |
c71a8961 ACM |
1281 | blk_tracer_stop(tr); |
1282 | } | |
1283 | ||
e4955c99 | 1284 | static const struct { |
c71a8961 | 1285 | const char *act[2]; |
ef18012b | 1286 | int (*print)(struct trace_seq *s, const struct trace_entry *ent); |
e4955c99 | 1287 | } what2act[] = { |
ef18012b | 1288 | [__BLK_TA_QUEUE] = {{ "Q", "queue" }, blk_log_generic }, |
c71a8961 ACM |
1289 | [__BLK_TA_BACKMERGE] = {{ "M", "backmerge" }, blk_log_generic }, |
1290 | [__BLK_TA_FRONTMERGE] = {{ "F", "frontmerge" }, blk_log_generic }, | |
1291 | [__BLK_TA_GETRQ] = {{ "G", "getrq" }, blk_log_generic }, | |
1292 | [__BLK_TA_SLEEPRQ] = {{ "S", "sleeprq" }, blk_log_generic }, | |
1293 | [__BLK_TA_REQUEUE] = {{ "R", "requeue" }, blk_log_with_error }, | |
1294 | [__BLK_TA_ISSUE] = {{ "D", "issue" }, blk_log_generic }, | |
1295 | [__BLK_TA_COMPLETE] = {{ "C", "complete" }, blk_log_with_error }, | |
1296 | [__BLK_TA_PLUG] = {{ "P", "plug" }, blk_log_plug }, | |
1297 | [__BLK_TA_UNPLUG_IO] = {{ "U", "unplug_io" }, blk_log_unplug }, | |
1298 | [__BLK_TA_UNPLUG_TIMER] = {{ "UT", "unplug_timer" }, blk_log_unplug }, | |
1299 | [__BLK_TA_INSERT] = {{ "I", "insert" }, blk_log_generic }, | |
1300 | [__BLK_TA_SPLIT] = {{ "X", "split" }, blk_log_split }, | |
1301 | [__BLK_TA_BOUNCE] = {{ "B", "bounce" }, blk_log_generic }, | |
1302 | [__BLK_TA_REMAP] = {{ "A", "remap" }, blk_log_remap }, | |
1303 | }; | |
1304 | ||
b6a4b0c3 LZ |
1305 | static enum print_line_t print_one_line(struct trace_iterator *iter, |
1306 | bool classic) | |
c71a8961 | 1307 | { |
2c9b238e | 1308 | struct trace_seq *s = &iter->seq; |
b6a4b0c3 LZ |
1309 | const struct blk_io_trace *t; |
1310 | u16 what; | |
c71a8961 | 1311 | int ret; |
b6a4b0c3 LZ |
1312 | bool long_act; |
1313 | blk_log_action_t *log_action; | |
c71a8961 | 1314 | |
b6a4b0c3 LZ |
1315 | t = te_blk_io_trace(iter->ent); |
1316 | what = t->action & ((1 << BLK_TC_SHIFT) - 1); | |
1317 | long_act = !!(trace_flags & TRACE_ITER_VERBOSE); | |
1318 | log_action = classic ? &blk_log_action_classic : &blk_log_action; | |
08a06b83 | 1319 | |
18cea459 LZ |
1320 | if (t->action == BLK_TN_MESSAGE) { |
1321 | ret = log_action(iter, long_act ? "message" : "m"); | |
1322 | if (ret) | |
1323 | ret = blk_log_msg(s, iter->ent); | |
1324 | goto out; | |
1325 | } | |
1326 | ||
eb08f8eb | 1327 | if (unlikely(what == 0 || what >= ARRAY_SIZE(what2act))) |
b78825d6 | 1328 | ret = trace_seq_printf(s, "Unknown action %x\n", what); |
c71a8961 | 1329 | else { |
b6a4b0c3 | 1330 | ret = log_action(iter, what2act[what].act[long_act]); |
c71a8961 | 1331 | if (ret) |
2c9b238e | 1332 | ret = what2act[what].print(s, iter->ent); |
c71a8961 | 1333 | } |
18cea459 | 1334 | out: |
c71a8961 ACM |
1335 | return ret ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; |
1336 | } | |
1337 | ||
b6a4b0c3 LZ |
1338 | static enum print_line_t blk_trace_event_print(struct trace_iterator *iter, |
1339 | int flags) | |
1340 | { | |
b6a4b0c3 LZ |
1341 | return print_one_line(iter, false); |
1342 | } | |
1343 | ||
08a06b83 ACM |
1344 | static int blk_trace_synthesize_old_trace(struct trace_iterator *iter) |
1345 | { | |
1346 | struct trace_seq *s = &iter->seq; | |
1347 | struct blk_io_trace *t = (struct blk_io_trace *)iter->ent; | |
1348 | const int offset = offsetof(struct blk_io_trace, sector); | |
1349 | struct blk_io_trace old = { | |
1350 | .magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION, | |
6c051ce0 | 1351 | .time = iter->ts, |
08a06b83 ACM |
1352 | }; |
1353 | ||
1354 | if (!trace_seq_putmem(s, &old, offset)) | |
1355 | return 0; | |
1356 | return trace_seq_putmem(s, &t->sector, | |
1357 | sizeof(old) - offset + t->pdu_len); | |
1358 | } | |
1359 | ||
ae7462b4 ACM |
1360 | static enum print_line_t |
1361 | blk_trace_event_print_binary(struct trace_iterator *iter, int flags) | |
08a06b83 ACM |
1362 | { |
1363 | return blk_trace_synthesize_old_trace(iter) ? | |
1364 | TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; | |
1365 | } | |
1366 | ||
c71a8961 ACM |
1367 | static enum print_line_t blk_tracer_print_line(struct trace_iterator *iter) |
1368 | { | |
c71a8961 ACM |
1369 | if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) |
1370 | return TRACE_TYPE_UNHANDLED; | |
1371 | ||
b6a4b0c3 | 1372 | return print_one_line(iter, true); |
c71a8961 ACM |
1373 | } |
1374 | ||
f3948f88 LZ |
1375 | static int blk_tracer_set_flag(u32 old_flags, u32 bit, int set) |
1376 | { | |
1377 | /* don't output context-info for blk_classic output */ | |
1378 | if (bit == TRACE_BLK_OPT_CLASSIC) { | |
1379 | if (set) | |
1380 | trace_flags &= ~TRACE_ITER_CONTEXT_INFO; | |
1381 | else | |
1382 | trace_flags |= TRACE_ITER_CONTEXT_INFO; | |
1383 | } | |
1384 | return 0; | |
1385 | } | |
1386 | ||
c71a8961 ACM |
1387 | static struct tracer blk_tracer __read_mostly = { |
1388 | .name = "blk", | |
1389 | .init = blk_tracer_init, | |
1390 | .reset = blk_tracer_reset, | |
1391 | .start = blk_tracer_start, | |
1392 | .stop = blk_tracer_stop, | |
1393 | .print_header = blk_tracer_print_header, | |
1394 | .print_line = blk_tracer_print_line, | |
1395 | .flags = &blk_tracer_flags, | |
f3948f88 | 1396 | .set_flag = blk_tracer_set_flag, |
c71a8961 ACM |
1397 | }; |
1398 | ||
1399 | static struct trace_event trace_blk_event = { | |
ef18012b | 1400 | .type = TRACE_BLK, |
c71a8961 | 1401 | .trace = blk_trace_event_print, |
08a06b83 | 1402 | .binary = blk_trace_event_print_binary, |
c71a8961 ACM |
1403 | }; |
1404 | ||
1405 | static int __init init_blk_tracer(void) | |
1406 | { | |
1407 | if (!register_ftrace_event(&trace_blk_event)) { | |
1408 | pr_warning("Warning: could not register block events\n"); | |
1409 | return 1; | |
1410 | } | |
1411 | ||
1412 | if (register_tracer(&blk_tracer) != 0) { | |
1413 | pr_warning("Warning: could not register the block tracer\n"); | |
1414 | unregister_ftrace_event(&trace_blk_event); | |
1415 | return 1; | |
1416 | } | |
1417 | ||
1418 | return 0; | |
1419 | } | |
1420 | ||
1421 | device_initcall(init_blk_tracer); | |
1422 | ||
1423 | static int blk_trace_remove_queue(struct request_queue *q) | |
1424 | { | |
1425 | struct blk_trace *bt; | |
1426 | ||
1427 | bt = xchg(&q->blk_trace, NULL); | |
1428 | if (bt == NULL) | |
1429 | return -EINVAL; | |
1430 | ||
17ba97e3 LZ |
1431 | if (atomic_dec_and_test(&blk_probes_ref)) |
1432 | blk_unregister_tracepoints(); | |
1433 | ||
ad5dd549 | 1434 | blk_trace_free(bt); |
c71a8961 ACM |
1435 | return 0; |
1436 | } | |
1437 | ||
1438 | /* | |
1439 | * Setup everything required to start tracing | |
1440 | */ | |
9908c309 LZ |
1441 | static int blk_trace_setup_queue(struct request_queue *q, |
1442 | struct block_device *bdev) | |
c71a8961 ACM |
1443 | { |
1444 | struct blk_trace *old_bt, *bt = NULL; | |
18cea459 | 1445 | int ret = -ENOMEM; |
c71a8961 | 1446 | |
c71a8961 ACM |
1447 | bt = kzalloc(sizeof(*bt), GFP_KERNEL); |
1448 | if (!bt) | |
15152e44 | 1449 | return -ENOMEM; |
c71a8961 | 1450 | |
18cea459 LZ |
1451 | bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); |
1452 | if (!bt->msg_data) | |
1453 | goto free_bt; | |
1454 | ||
9908c309 | 1455 | bt->dev = bdev->bd_dev; |
c71a8961 | 1456 | bt->act_mask = (u16)-1; |
9908c309 LZ |
1457 | |
1458 | blk_trace_setup_lba(bt, bdev); | |
c71a8961 ACM |
1459 | |
1460 | old_bt = xchg(&q->blk_trace, bt); | |
1461 | if (old_bt != NULL) { | |
1462 | (void)xchg(&q->blk_trace, old_bt); | |
18cea459 LZ |
1463 | ret = -EBUSY; |
1464 | goto free_bt; | |
c71a8961 | 1465 | } |
15152e44 | 1466 | |
17ba97e3 LZ |
1467 | if (atomic_inc_return(&blk_probes_ref) == 1) |
1468 | blk_register_tracepoints(); | |
c71a8961 | 1469 | return 0; |
18cea459 LZ |
1470 | |
1471 | free_bt: | |
1472 | blk_trace_free(bt); | |
1473 | return ret; | |
c71a8961 ACM |
1474 | } |
1475 | ||
1476 | /* | |
1477 | * sysfs interface to enable and configure tracing | |
1478 | */ | |
1479 | ||
c71a8961 ACM |
1480 | static ssize_t sysfs_blk_trace_attr_show(struct device *dev, |
1481 | struct device_attribute *attr, | |
1482 | char *buf); | |
1483 | static ssize_t sysfs_blk_trace_attr_store(struct device *dev, | |
1484 | struct device_attribute *attr, | |
1485 | const char *buf, size_t count); | |
1486 | #define BLK_TRACE_DEVICE_ATTR(_name) \ | |
1487 | DEVICE_ATTR(_name, S_IRUGO | S_IWUSR, \ | |
1488 | sysfs_blk_trace_attr_show, \ | |
1489 | sysfs_blk_trace_attr_store) | |
1490 | ||
cd649b8b | 1491 | static BLK_TRACE_DEVICE_ATTR(enable); |
c71a8961 ACM |
1492 | static BLK_TRACE_DEVICE_ATTR(act_mask); |
1493 | static BLK_TRACE_DEVICE_ATTR(pid); | |
1494 | static BLK_TRACE_DEVICE_ATTR(start_lba); | |
1495 | static BLK_TRACE_DEVICE_ATTR(end_lba); | |
1496 | ||
1497 | static struct attribute *blk_trace_attrs[] = { | |
1498 | &dev_attr_enable.attr, | |
1499 | &dev_attr_act_mask.attr, | |
1500 | &dev_attr_pid.attr, | |
1501 | &dev_attr_start_lba.attr, | |
1502 | &dev_attr_end_lba.attr, | |
1503 | NULL | |
1504 | }; | |
1505 | ||
1506 | struct attribute_group blk_trace_attr_group = { | |
1507 | .name = "trace", | |
1508 | .attrs = blk_trace_attrs, | |
1509 | }; | |
1510 | ||
09341997 LZ |
1511 | static const struct { |
1512 | int mask; | |
1513 | const char *str; | |
1514 | } mask_maps[] = { | |
1515 | { BLK_TC_READ, "read" }, | |
1516 | { BLK_TC_WRITE, "write" }, | |
1517 | { BLK_TC_BARRIER, "barrier" }, | |
1518 | { BLK_TC_SYNC, "sync" }, | |
1519 | { BLK_TC_QUEUE, "queue" }, | |
1520 | { BLK_TC_REQUEUE, "requeue" }, | |
1521 | { BLK_TC_ISSUE, "issue" }, | |
1522 | { BLK_TC_COMPLETE, "complete" }, | |
1523 | { BLK_TC_FS, "fs" }, | |
1524 | { BLK_TC_PC, "pc" }, | |
1525 | { BLK_TC_AHEAD, "ahead" }, | |
1526 | { BLK_TC_META, "meta" }, | |
1527 | { BLK_TC_DISCARD, "discard" }, | |
1528 | { BLK_TC_DRV_DATA, "drv_data" }, | |
1529 | }; | |
1530 | ||
1531 | static int blk_trace_str2mask(const char *str) | |
c71a8961 | 1532 | { |
09341997 | 1533 | int i; |
c71a8961 | 1534 | int mask = 0; |
9eb85125 | 1535 | char *buf, *s, *token; |
c71a8961 | 1536 | |
9eb85125 LZ |
1537 | buf = kstrdup(str, GFP_KERNEL); |
1538 | if (buf == NULL) | |
c71a8961 | 1539 | return -ENOMEM; |
9eb85125 | 1540 | s = strstrip(buf); |
c71a8961 ACM |
1541 | |
1542 | while (1) { | |
09341997 LZ |
1543 | token = strsep(&s, ","); |
1544 | if (token == NULL) | |
c71a8961 ACM |
1545 | break; |
1546 | ||
09341997 LZ |
1547 | if (*token == '\0') |
1548 | continue; | |
1549 | ||
1550 | for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { | |
1551 | if (strcasecmp(token, mask_maps[i].str) == 0) { | |
1552 | mask |= mask_maps[i].mask; | |
1553 | break; | |
1554 | } | |
1555 | } | |
1556 | if (i == ARRAY_SIZE(mask_maps)) { | |
1557 | mask = -EINVAL; | |
1558 | break; | |
1559 | } | |
c71a8961 | 1560 | } |
9eb85125 | 1561 | kfree(buf); |
c71a8961 ACM |
1562 | |
1563 | return mask; | |
1564 | } | |
1565 | ||
09341997 LZ |
1566 | static ssize_t blk_trace_mask2str(char *buf, int mask) |
1567 | { | |
1568 | int i; | |
1569 | char *p = buf; | |
1570 | ||
1571 | for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { | |
1572 | if (mask & mask_maps[i].mask) { | |
1573 | p += sprintf(p, "%s%s", | |
1574 | (p == buf) ? "" : ",", mask_maps[i].str); | |
1575 | } | |
1576 | } | |
1577 | *p++ = '\n'; | |
1578 | ||
1579 | return p - buf; | |
1580 | } | |
1581 | ||
b125130b LZ |
1582 | static struct request_queue *blk_trace_get_queue(struct block_device *bdev) |
1583 | { | |
1584 | if (bdev->bd_disk == NULL) | |
1585 | return NULL; | |
1586 | ||
1587 | return bdev_get_queue(bdev); | |
1588 | } | |
1589 | ||
c71a8961 ACM |
1590 | static ssize_t sysfs_blk_trace_attr_show(struct device *dev, |
1591 | struct device_attribute *attr, | |
1592 | char *buf) | |
1593 | { | |
1594 | struct hd_struct *p = dev_to_part(dev); | |
1595 | struct request_queue *q; | |
1596 | struct block_device *bdev; | |
1597 | ssize_t ret = -ENXIO; | |
1598 | ||
1599 | lock_kernel(); | |
1600 | bdev = bdget(part_devt(p)); | |
1601 | if (bdev == NULL) | |
1602 | goto out_unlock_kernel; | |
1603 | ||
b125130b | 1604 | q = blk_trace_get_queue(bdev); |
c71a8961 ACM |
1605 | if (q == NULL) |
1606 | goto out_bdput; | |
b125130b | 1607 | |
c71a8961 | 1608 | mutex_lock(&bdev->bd_mutex); |
cd649b8b LZ |
1609 | |
1610 | if (attr == &dev_attr_enable) { | |
1611 | ret = sprintf(buf, "%u\n", !!q->blk_trace); | |
1612 | goto out_unlock_bdev; | |
1613 | } | |
1614 | ||
c71a8961 ACM |
1615 | if (q->blk_trace == NULL) |
1616 | ret = sprintf(buf, "disabled\n"); | |
1617 | else if (attr == &dev_attr_act_mask) | |
09341997 | 1618 | ret = blk_trace_mask2str(buf, q->blk_trace->act_mask); |
c71a8961 ACM |
1619 | else if (attr == &dev_attr_pid) |
1620 | ret = sprintf(buf, "%u\n", q->blk_trace->pid); | |
1621 | else if (attr == &dev_attr_start_lba) | |
1622 | ret = sprintf(buf, "%llu\n", q->blk_trace->start_lba); | |
1623 | else if (attr == &dev_attr_end_lba) | |
1624 | ret = sprintf(buf, "%llu\n", q->blk_trace->end_lba); | |
cd649b8b LZ |
1625 | |
1626 | out_unlock_bdev: | |
c71a8961 ACM |
1627 | mutex_unlock(&bdev->bd_mutex); |
1628 | out_bdput: | |
1629 | bdput(bdev); | |
1630 | out_unlock_kernel: | |
1631 | unlock_kernel(); | |
1632 | return ret; | |
1633 | } | |
1634 | ||
1635 | static ssize_t sysfs_blk_trace_attr_store(struct device *dev, | |
1636 | struct device_attribute *attr, | |
1637 | const char *buf, size_t count) | |
1638 | { | |
1639 | struct block_device *bdev; | |
1640 | struct request_queue *q; | |
1641 | struct hd_struct *p; | |
1642 | u64 value; | |
09341997 | 1643 | ssize_t ret = -EINVAL; |
c71a8961 ACM |
1644 | |
1645 | if (count == 0) | |
1646 | goto out; | |
1647 | ||
1648 | if (attr == &dev_attr_act_mask) { | |
1649 | if (sscanf(buf, "%llx", &value) != 1) { | |
1650 | /* Assume it is a list of trace category names */ | |
09341997 LZ |
1651 | ret = blk_trace_str2mask(buf); |
1652 | if (ret < 0) | |
c71a8961 | 1653 | goto out; |
09341997 | 1654 | value = ret; |
c71a8961 ACM |
1655 | } |
1656 | } else if (sscanf(buf, "%llu", &value) != 1) | |
1657 | goto out; | |
1658 | ||
09341997 LZ |
1659 | ret = -ENXIO; |
1660 | ||
c71a8961 ACM |
1661 | lock_kernel(); |
1662 | p = dev_to_part(dev); | |
1663 | bdev = bdget(part_devt(p)); | |
1664 | if (bdev == NULL) | |
1665 | goto out_unlock_kernel; | |
1666 | ||
b125130b | 1667 | q = blk_trace_get_queue(bdev); |
c71a8961 ACM |
1668 | if (q == NULL) |
1669 | goto out_bdput; | |
1670 | ||
1671 | mutex_lock(&bdev->bd_mutex); | |
cd649b8b LZ |
1672 | |
1673 | if (attr == &dev_attr_enable) { | |
1674 | if (value) | |
9908c309 | 1675 | ret = blk_trace_setup_queue(q, bdev); |
cd649b8b LZ |
1676 | else |
1677 | ret = blk_trace_remove_queue(q); | |
1678 | goto out_unlock_bdev; | |
1679 | } | |
1680 | ||
c71a8961 ACM |
1681 | ret = 0; |
1682 | if (q->blk_trace == NULL) | |
9908c309 | 1683 | ret = blk_trace_setup_queue(q, bdev); |
c71a8961 ACM |
1684 | |
1685 | if (ret == 0) { | |
1686 | if (attr == &dev_attr_act_mask) | |
1687 | q->blk_trace->act_mask = value; | |
1688 | else if (attr == &dev_attr_pid) | |
1689 | q->blk_trace->pid = value; | |
1690 | else if (attr == &dev_attr_start_lba) | |
1691 | q->blk_trace->start_lba = value; | |
1692 | else if (attr == &dev_attr_end_lba) | |
1693 | q->blk_trace->end_lba = value; | |
c71a8961 | 1694 | } |
cd649b8b LZ |
1695 | |
1696 | out_unlock_bdev: | |
c71a8961 ACM |
1697 | mutex_unlock(&bdev->bd_mutex); |
1698 | out_bdput: | |
1699 | bdput(bdev); | |
1700 | out_unlock_kernel: | |
1701 | unlock_kernel(); | |
1702 | out: | |
cd649b8b | 1703 | return ret ? ret : count; |
c71a8961 | 1704 | } |
cd649b8b | 1705 | |
1d54ad6d LZ |
1706 | int blk_trace_init_sysfs(struct device *dev) |
1707 | { | |
1708 | return sysfs_create_group(&dev->kobj, &blk_trace_attr_group); | |
1709 | } | |
1710 | ||
48c0d4d4 ZK |
1711 | void blk_trace_remove_sysfs(struct device *dev) |
1712 | { | |
1713 | sysfs_remove_group(&dev->kobj, &blk_trace_attr_group); | |
1714 | } | |
1715 | ||
55782138 LZ |
1716 | #endif /* CONFIG_BLK_DEV_IO_TRACE */ |
1717 | ||
1718 | #ifdef CONFIG_EVENT_TRACING | |
1719 | ||
1720 | void blk_dump_cmd(char *buf, struct request *rq) | |
1721 | { | |
1722 | int i, end; | |
1723 | int len = rq->cmd_len; | |
1724 | unsigned char *cmd = rq->cmd; | |
1725 | ||
1726 | if (!blk_pc_request(rq)) { | |
1727 | buf[0] = '\0'; | |
1728 | return; | |
1729 | } | |
1730 | ||
1731 | for (end = len - 1; end >= 0; end--) | |
1732 | if (cmd[end]) | |
1733 | break; | |
1734 | end++; | |
1735 | ||
1736 | for (i = 0; i < len; i++) { | |
1737 | buf += sprintf(buf, "%s%02x", i == 0 ? "" : " ", cmd[i]); | |
1738 | if (i == end && end != len - 1) { | |
1739 | sprintf(buf, " .."); | |
1740 | break; | |
1741 | } | |
1742 | } | |
1743 | } | |
1744 | ||
1745 | void blk_fill_rwbs(char *rwbs, u32 rw, int bytes) | |
1746 | { | |
1747 | int i = 0; | |
1748 | ||
1749 | if (rw & WRITE) | |
1750 | rwbs[i++] = 'W'; | |
1751 | else if (rw & 1 << BIO_RW_DISCARD) | |
1752 | rwbs[i++] = 'D'; | |
1753 | else if (bytes) | |
1754 | rwbs[i++] = 'R'; | |
1755 | else | |
1756 | rwbs[i++] = 'N'; | |
1757 | ||
1758 | if (rw & 1 << BIO_RW_AHEAD) | |
1759 | rwbs[i++] = 'A'; | |
1760 | if (rw & 1 << BIO_RW_BARRIER) | |
1761 | rwbs[i++] = 'B'; | |
1762 | if (rw & 1 << BIO_RW_SYNCIO) | |
1763 | rwbs[i++] = 'S'; | |
1764 | if (rw & 1 << BIO_RW_META) | |
1765 | rwbs[i++] = 'M'; | |
1766 | ||
1767 | rwbs[i] = '\0'; | |
1768 | } | |
1769 | ||
1770 | void blk_fill_rwbs_rq(char *rwbs, struct request *rq) | |
1771 | { | |
1772 | int rw = rq->cmd_flags & 0x03; | |
1773 | int bytes; | |
1774 | ||
1775 | if (blk_discard_rq(rq)) | |
1776 | rw |= (1 << BIO_RW_DISCARD); | |
1777 | ||
c9059598 | 1778 | bytes = blk_rq_bytes(rq); |
55782138 LZ |
1779 | |
1780 | blk_fill_rwbs(rwbs, rw, bytes); | |
1781 | } | |
1782 | ||
1783 | #endif /* CONFIG_EVENT_TRACING */ | |
1784 |