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> |
6e5fdeed | 26 | #include <linux/export.h> |
be1c6341 | 27 | #include <linux/time.h> |
939b3669 | 28 | #include <linux/uaccess.h> |
55782138 LZ |
29 | |
30 | #include <trace/events/block.h> | |
31 | ||
2db270a8 | 32 | #include "trace_output.h" |
2056a782 | 33 | |
55782138 LZ |
34 | #ifdef CONFIG_BLK_DEV_IO_TRACE |
35 | ||
2056a782 JA |
36 | static unsigned int blktrace_seq __read_mostly = 1; |
37 | ||
c71a8961 | 38 | static struct trace_array *blk_tr; |
5006ea73 | 39 | static bool blk_tracer_enabled __read_mostly; |
c71a8961 ACM |
40 | |
41 | /* Select an alternative, minimalistic output than the original one */ | |
ef18012b | 42 | #define TRACE_BLK_OPT_CLASSIC 0x1 |
c71a8961 ACM |
43 | |
44 | static struct tracer_opt blk_tracer_opts[] = { | |
45 | /* Default disable the minimalistic output */ | |
157f9c00 | 46 | { TRACER_OPT(blk_classic, TRACE_BLK_OPT_CLASSIC) }, |
c71a8961 ACM |
47 | { } |
48 | }; | |
49 | ||
50 | static struct tracer_flags blk_tracer_flags = { | |
51 | .val = 0, | |
52 | .opts = blk_tracer_opts, | |
53 | }; | |
54 | ||
5f3ea37c | 55 | /* Global reference count of probes */ |
5f3ea37c ACM |
56 | static atomic_t blk_probes_ref = ATOMIC_INIT(0); |
57 | ||
3c289ba7 | 58 | static void blk_register_tracepoints(void); |
5f3ea37c ACM |
59 | static void blk_unregister_tracepoints(void); |
60 | ||
be1c6341 OK |
61 | /* |
62 | * Send out a notify message. | |
63 | */ | |
a863055b JA |
64 | static void trace_note(struct blk_trace *bt, pid_t pid, int action, |
65 | const void *data, size_t len) | |
be1c6341 OK |
66 | { |
67 | struct blk_io_trace *t; | |
18cea459 | 68 | struct ring_buffer_event *event = NULL; |
e77405ad | 69 | struct ring_buffer *buffer = NULL; |
18cea459 LZ |
70 | int pc = 0; |
71 | int cpu = smp_processor_id(); | |
72 | bool blk_tracer = blk_tracer_enabled; | |
73 | ||
74 | if (blk_tracer) { | |
e77405ad | 75 | buffer = blk_tr->buffer; |
18cea459 | 76 | pc = preempt_count(); |
e77405ad | 77 | event = trace_buffer_lock_reserve(buffer, TRACE_BLK, |
18cea459 LZ |
78 | sizeof(*t) + len, |
79 | 0, pc); | |
80 | if (!event) | |
81 | return; | |
82 | t = ring_buffer_event_data(event); | |
83 | goto record_it; | |
84 | } | |
be1c6341 | 85 | |
c71a8961 ACM |
86 | if (!bt->rchan) |
87 | return; | |
88 | ||
be1c6341 | 89 | t = relay_reserve(bt->rchan, sizeof(*t) + len); |
d3d9d2a5 | 90 | if (t) { |
d3d9d2a5 | 91 | t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; |
2997c8c4 | 92 | t->time = ktime_to_ns(ktime_get()); |
18cea459 | 93 | record_it: |
d3d9d2a5 JA |
94 | t->device = bt->dev; |
95 | t->action = action; | |
96 | t->pid = pid; | |
97 | t->cpu = cpu; | |
98 | t->pdu_len = len; | |
99 | memcpy((void *) t + sizeof(*t), data, len); | |
18cea459 LZ |
100 | |
101 | if (blk_tracer) | |
e77405ad | 102 | trace_buffer_unlock_commit(buffer, event, 0, pc); |
d3d9d2a5 | 103 | } |
be1c6341 OK |
104 | } |
105 | ||
2056a782 JA |
106 | /* |
107 | * Send out a notify for this process, if we haven't done so since a trace | |
108 | * started | |
109 | */ | |
110 | static void trace_note_tsk(struct blk_trace *bt, struct task_struct *tsk) | |
111 | { | |
a863055b JA |
112 | tsk->btrace_seq = blktrace_seq; |
113 | trace_note(bt, tsk->pid, BLK_TN_PROCESS, tsk->comm, sizeof(tsk->comm)); | |
be1c6341 | 114 | } |
2056a782 | 115 | |
be1c6341 OK |
116 | static void trace_note_time(struct blk_trace *bt) |
117 | { | |
118 | struct timespec now; | |
119 | unsigned long flags; | |
120 | u32 words[2]; | |
121 | ||
122 | getnstimeofday(&now); | |
123 | words[0] = now.tv_sec; | |
124 | words[1] = now.tv_nsec; | |
125 | ||
126 | local_irq_save(flags); | |
127 | trace_note(bt, 0, BLK_TN_TIMESTAMP, words, sizeof(words)); | |
128 | local_irq_restore(flags); | |
2056a782 JA |
129 | } |
130 | ||
9d5f09a4 AB |
131 | void __trace_note_message(struct blk_trace *bt, const char *fmt, ...) |
132 | { | |
133 | int n; | |
134 | va_list args; | |
14a73f54 | 135 | unsigned long flags; |
64565911 | 136 | char *buf; |
9d5f09a4 | 137 | |
18cea459 LZ |
138 | if (unlikely(bt->trace_state != Blktrace_running && |
139 | !blk_tracer_enabled)) | |
c71a8961 ACM |
140 | return; |
141 | ||
490da40d TM |
142 | /* |
143 | * If the BLK_TC_NOTIFY action mask isn't set, don't send any note | |
144 | * message to the trace. | |
145 | */ | |
146 | if (!(bt->act_mask & BLK_TC_NOTIFY)) | |
147 | return; | |
148 | ||
14a73f54 | 149 | local_irq_save(flags); |
d8a0349c | 150 | buf = this_cpu_ptr(bt->msg_data); |
9d5f09a4 | 151 | va_start(args, fmt); |
64565911 | 152 | n = vscnprintf(buf, BLK_TN_MAX_MSG, fmt, args); |
9d5f09a4 AB |
153 | va_end(args); |
154 | ||
64565911 | 155 | trace_note(bt, 0, BLK_TN_MESSAGE, buf, n); |
14a73f54 | 156 | local_irq_restore(flags); |
9d5f09a4 AB |
157 | } |
158 | EXPORT_SYMBOL_GPL(__trace_note_message); | |
159 | ||
2056a782 JA |
160 | static int act_log_check(struct blk_trace *bt, u32 what, sector_t sector, |
161 | pid_t pid) | |
162 | { | |
163 | if (((bt->act_mask << BLK_TC_SHIFT) & what) == 0) | |
164 | return 1; | |
d0deef5b | 165 | if (sector && (sector < bt->start_lba || sector > bt->end_lba)) |
2056a782 JA |
166 | return 1; |
167 | if (bt->pid && pid != bt->pid) | |
168 | return 1; | |
169 | ||
170 | return 0; | |
171 | } | |
172 | ||
173 | /* | |
174 | * Data direction bit lookup | |
175 | */ | |
e4955c99 LZ |
176 | static const u32 ddir_act[2] = { BLK_TC_ACT(BLK_TC_READ), |
177 | BLK_TC_ACT(BLK_TC_WRITE) }; | |
2056a782 | 178 | |
7b6d91da CH |
179 | #define BLK_TC_RAHEAD BLK_TC_AHEAD |
180 | ||
35ba8f70 | 181 | /* The ilog2() calls fall out because they're constant */ |
7b6d91da CH |
182 | #define MASK_TC_BIT(rw, __name) ((rw & REQ_ ## __name) << \ |
183 | (ilog2(BLK_TC_ ## __name) + BLK_TC_SHIFT - __REQ_ ## __name)) | |
2056a782 JA |
184 | |
185 | /* | |
186 | * The worker for the various blk_add_trace*() types. Fills out a | |
187 | * blk_io_trace structure and places it in a per-cpu subbuffer. | |
188 | */ | |
5f3ea37c | 189 | static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, |
2056a782 JA |
190 | int rw, u32 what, int error, int pdu_len, void *pdu_data) |
191 | { | |
192 | struct task_struct *tsk = current; | |
c71a8961 | 193 | struct ring_buffer_event *event = NULL; |
e77405ad | 194 | struct ring_buffer *buffer = NULL; |
2056a782 | 195 | struct blk_io_trace *t; |
0a987751 | 196 | unsigned long flags = 0; |
2056a782 JA |
197 | unsigned long *sequence; |
198 | pid_t pid; | |
c71a8961 | 199 | int cpu, pc = 0; |
18cea459 | 200 | bool blk_tracer = blk_tracer_enabled; |
2056a782 | 201 | |
18cea459 | 202 | if (unlikely(bt->trace_state != Blktrace_running && !blk_tracer)) |
2056a782 JA |
203 | return; |
204 | ||
205 | what |= ddir_act[rw & WRITE]; | |
7b6d91da CH |
206 | what |= MASK_TC_BIT(rw, SYNC); |
207 | what |= MASK_TC_BIT(rw, RAHEAD); | |
35ba8f70 DW |
208 | what |= MASK_TC_BIT(rw, META); |
209 | what |= MASK_TC_BIT(rw, DISCARD); | |
c09c47ca NK |
210 | what |= MASK_TC_BIT(rw, FLUSH); |
211 | what |= MASK_TC_BIT(rw, FUA); | |
2056a782 JA |
212 | |
213 | pid = tsk->pid; | |
d0deef5b | 214 | if (act_log_check(bt, what, sector, pid)) |
2056a782 | 215 | return; |
c71a8961 ACM |
216 | cpu = raw_smp_processor_id(); |
217 | ||
18cea459 | 218 | if (blk_tracer) { |
c71a8961 ACM |
219 | tracing_record_cmdline(current); |
220 | ||
e77405ad | 221 | buffer = blk_tr->buffer; |
51a763dd | 222 | pc = preempt_count(); |
e77405ad | 223 | event = trace_buffer_lock_reserve(buffer, TRACE_BLK, |
51a763dd ACM |
224 | sizeof(*t) + pdu_len, |
225 | 0, pc); | |
c71a8961 ACM |
226 | if (!event) |
227 | return; | |
51a763dd | 228 | t = ring_buffer_event_data(event); |
c71a8961 ACM |
229 | goto record_it; |
230 | } | |
2056a782 JA |
231 | |
232 | /* | |
233 | * A word about the locking here - we disable interrupts to reserve | |
234 | * some space in the relay per-cpu buffer, to prevent an irq | |
14a73f54 | 235 | * from coming in and stepping on our toes. |
2056a782 JA |
236 | */ |
237 | local_irq_save(flags); | |
238 | ||
239 | if (unlikely(tsk->btrace_seq != blktrace_seq)) | |
240 | trace_note_tsk(bt, tsk); | |
241 | ||
242 | t = relay_reserve(bt->rchan, sizeof(*t) + pdu_len); | |
243 | if (t) { | |
2056a782 JA |
244 | sequence = per_cpu_ptr(bt->sequence, cpu); |
245 | ||
246 | t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; | |
247 | t->sequence = ++(*sequence); | |
2997c8c4 | 248 | t->time = ktime_to_ns(ktime_get()); |
c71a8961 | 249 | record_it: |
08a06b83 | 250 | /* |
939b3669 ACM |
251 | * These two are not needed in ftrace as they are in the |
252 | * generic trace_entry, filled by tracing_generic_entry_update, | |
253 | * but for the trace_event->bin() synthesizer benefit we do it | |
254 | * here too. | |
255 | */ | |
256 | t->cpu = cpu; | |
257 | t->pid = pid; | |
08a06b83 | 258 | |
2056a782 JA |
259 | t->sector = sector; |
260 | t->bytes = bytes; | |
261 | t->action = what; | |
2056a782 | 262 | t->device = bt->dev; |
2056a782 JA |
263 | t->error = error; |
264 | t->pdu_len = pdu_len; | |
265 | ||
266 | if (pdu_len) | |
267 | memcpy((void *) t + sizeof(*t), pdu_data, pdu_len); | |
c71a8961 | 268 | |
18cea459 | 269 | if (blk_tracer) { |
e77405ad | 270 | trace_buffer_unlock_commit(buffer, event, 0, pc); |
c71a8961 ACM |
271 | return; |
272 | } | |
2056a782 JA |
273 | } |
274 | ||
275 | local_irq_restore(flags); | |
276 | } | |
277 | ||
2056a782 | 278 | static struct dentry *blk_tree_root; |
11a57153 | 279 | static DEFINE_MUTEX(blk_tree_mutex); |
2056a782 | 280 | |
ad5dd549 | 281 | static void blk_trace_free(struct blk_trace *bt) |
2056a782 | 282 | { |
02c62304 | 283 | debugfs_remove(bt->msg_file); |
2056a782 | 284 | debugfs_remove(bt->dropped_file); |
f48fc4d3 | 285 | relay_close(bt->rchan); |
39cbb602 | 286 | debugfs_remove(bt->dir); |
2056a782 | 287 | free_percpu(bt->sequence); |
64565911 | 288 | free_percpu(bt->msg_data); |
2056a782 | 289 | kfree(bt); |
ad5dd549 LZ |
290 | } |
291 | ||
292 | static void blk_trace_cleanup(struct blk_trace *bt) | |
293 | { | |
294 | blk_trace_free(bt); | |
5f3ea37c ACM |
295 | if (atomic_dec_and_test(&blk_probes_ref)) |
296 | blk_unregister_tracepoints(); | |
2056a782 JA |
297 | } |
298 | ||
6da127ad | 299 | int blk_trace_remove(struct request_queue *q) |
2056a782 JA |
300 | { |
301 | struct blk_trace *bt; | |
302 | ||
303 | bt = xchg(&q->blk_trace, NULL); | |
304 | if (!bt) | |
305 | return -EINVAL; | |
306 | ||
55547204 | 307 | if (bt->trace_state != Blktrace_running) |
2056a782 JA |
308 | blk_trace_cleanup(bt); |
309 | ||
310 | return 0; | |
311 | } | |
6da127ad | 312 | EXPORT_SYMBOL_GPL(blk_trace_remove); |
2056a782 | 313 | |
2056a782 JA |
314 | static ssize_t blk_dropped_read(struct file *filp, char __user *buffer, |
315 | size_t count, loff_t *ppos) | |
316 | { | |
317 | struct blk_trace *bt = filp->private_data; | |
318 | char buf[16]; | |
319 | ||
320 | snprintf(buf, sizeof(buf), "%u\n", atomic_read(&bt->dropped)); | |
321 | ||
322 | return simple_read_from_buffer(buffer, count, ppos, buf, strlen(buf)); | |
323 | } | |
324 | ||
2b8693c0 | 325 | static const struct file_operations blk_dropped_fops = { |
2056a782 | 326 | .owner = THIS_MODULE, |
234e3405 | 327 | .open = simple_open, |
2056a782 | 328 | .read = blk_dropped_read, |
6038f373 | 329 | .llseek = default_llseek, |
2056a782 JA |
330 | }; |
331 | ||
02c62304 AB |
332 | static ssize_t blk_msg_write(struct file *filp, const char __user *buffer, |
333 | size_t count, loff_t *ppos) | |
334 | { | |
335 | char *msg; | |
336 | struct blk_trace *bt; | |
337 | ||
7635b03a | 338 | if (count >= BLK_TN_MAX_MSG) |
02c62304 AB |
339 | return -EINVAL; |
340 | ||
a4b3ada8 | 341 | msg = kmalloc(count + 1, GFP_KERNEL); |
02c62304 AB |
342 | if (msg == NULL) |
343 | return -ENOMEM; | |
344 | ||
345 | if (copy_from_user(msg, buffer, count)) { | |
346 | kfree(msg); | |
347 | return -EFAULT; | |
348 | } | |
349 | ||
a4b3ada8 | 350 | msg[count] = '\0'; |
02c62304 AB |
351 | bt = filp->private_data; |
352 | __trace_note_message(bt, "%s", msg); | |
353 | kfree(msg); | |
354 | ||
355 | return count; | |
356 | } | |
357 | ||
358 | static const struct file_operations blk_msg_fops = { | |
359 | .owner = THIS_MODULE, | |
234e3405 | 360 | .open = simple_open, |
02c62304 | 361 | .write = blk_msg_write, |
6038f373 | 362 | .llseek = noop_llseek, |
02c62304 AB |
363 | }; |
364 | ||
2056a782 JA |
365 | /* |
366 | * Keep track of how many times we encountered a full subbuffer, to aid | |
367 | * the user space app in telling how many lost events there were. | |
368 | */ | |
369 | static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf, | |
370 | void *prev_subbuf, size_t prev_padding) | |
371 | { | |
372 | struct blk_trace *bt; | |
373 | ||
374 | if (!relay_buf_full(buf)) | |
375 | return 1; | |
376 | ||
377 | bt = buf->chan->private_data; | |
378 | atomic_inc(&bt->dropped); | |
379 | return 0; | |
380 | } | |
381 | ||
382 | static int blk_remove_buf_file_callback(struct dentry *dentry) | |
383 | { | |
384 | debugfs_remove(dentry); | |
f48fc4d3 | 385 | |
2056a782 JA |
386 | return 0; |
387 | } | |
388 | ||
389 | static struct dentry *blk_create_buf_file_callback(const char *filename, | |
390 | struct dentry *parent, | |
f4ae40a6 | 391 | umode_t mode, |
2056a782 JA |
392 | struct rchan_buf *buf, |
393 | int *is_global) | |
394 | { | |
395 | return debugfs_create_file(filename, mode, parent, buf, | |
396 | &relay_file_operations); | |
397 | } | |
398 | ||
399 | static struct rchan_callbacks blk_relay_callbacks = { | |
400 | .subbuf_start = blk_subbuf_start_callback, | |
401 | .create_buf_file = blk_create_buf_file_callback, | |
402 | .remove_buf_file = blk_remove_buf_file_callback, | |
403 | }; | |
404 | ||
9908c309 LZ |
405 | static void blk_trace_setup_lba(struct blk_trace *bt, |
406 | struct block_device *bdev) | |
407 | { | |
408 | struct hd_struct *part = NULL; | |
409 | ||
410 | if (bdev) | |
411 | part = bdev->bd_part; | |
412 | ||
413 | if (part) { | |
414 | bt->start_lba = part->start_sect; | |
415 | bt->end_lba = part->start_sect + part->nr_sects; | |
416 | } else { | |
417 | bt->start_lba = 0; | |
418 | bt->end_lba = -1ULL; | |
419 | } | |
420 | } | |
421 | ||
2056a782 JA |
422 | /* |
423 | * Setup everything required to start tracing | |
424 | */ | |
6da127ad | 425 | int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, |
d0deef5b SD |
426 | struct block_device *bdev, |
427 | struct blk_user_trace_setup *buts) | |
2056a782 | 428 | { |
2056a782 JA |
429 | struct blk_trace *old_bt, *bt = NULL; |
430 | struct dentry *dir = NULL; | |
2056a782 JA |
431 | int ret, i; |
432 | ||
171044d4 | 433 | if (!buts->buf_size || !buts->buf_nr) |
2056a782 JA |
434 | return -EINVAL; |
435 | ||
0497b345 JA |
436 | strncpy(buts->name, name, BLKTRACE_BDEV_SIZE); |
437 | buts->name[BLKTRACE_BDEV_SIZE - 1] = '\0'; | |
2056a782 JA |
438 | |
439 | /* | |
440 | * some device names have larger paths - convert the slashes | |
441 | * to underscores for this to work as expected | |
442 | */ | |
171044d4 AB |
443 | for (i = 0; i < strlen(buts->name); i++) |
444 | if (buts->name[i] == '/') | |
445 | buts->name[i] = '_'; | |
2056a782 | 446 | |
2056a782 JA |
447 | bt = kzalloc(sizeof(*bt), GFP_KERNEL); |
448 | if (!bt) | |
ad5dd549 | 449 | return -ENOMEM; |
2056a782 | 450 | |
ad5dd549 | 451 | ret = -ENOMEM; |
2056a782 JA |
452 | bt->sequence = alloc_percpu(unsigned long); |
453 | if (!bt->sequence) | |
454 | goto err; | |
455 | ||
313e458f | 456 | bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); |
64565911 JA |
457 | if (!bt->msg_data) |
458 | goto err; | |
459 | ||
2056a782 | 460 | ret = -ENOENT; |
f48fc4d3 | 461 | |
b5230b56 | 462 | mutex_lock(&blk_tree_mutex); |
f48fc4d3 JA |
463 | if (!blk_tree_root) { |
464 | blk_tree_root = debugfs_create_dir("block", NULL); | |
b5230b56 LZ |
465 | if (!blk_tree_root) { |
466 | mutex_unlock(&blk_tree_mutex); | |
1a17662e | 467 | goto err; |
b5230b56 | 468 | } |
f48fc4d3 | 469 | } |
b5230b56 | 470 | mutex_unlock(&blk_tree_mutex); |
f48fc4d3 JA |
471 | |
472 | dir = debugfs_create_dir(buts->name, blk_tree_root); | |
473 | ||
2056a782 JA |
474 | if (!dir) |
475 | goto err; | |
476 | ||
477 | bt->dir = dir; | |
6da127ad | 478 | bt->dev = dev; |
2056a782 JA |
479 | atomic_set(&bt->dropped, 0); |
480 | ||
481 | ret = -EIO; | |
939b3669 ACM |
482 | bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt, |
483 | &blk_dropped_fops); | |
2056a782 JA |
484 | if (!bt->dropped_file) |
485 | goto err; | |
486 | ||
02c62304 AB |
487 | bt->msg_file = debugfs_create_file("msg", 0222, dir, bt, &blk_msg_fops); |
488 | if (!bt->msg_file) | |
489 | goto err; | |
490 | ||
171044d4 AB |
491 | bt->rchan = relay_open("trace", dir, buts->buf_size, |
492 | buts->buf_nr, &blk_relay_callbacks, bt); | |
2056a782 JA |
493 | if (!bt->rchan) |
494 | goto err; | |
2056a782 | 495 | |
171044d4 | 496 | bt->act_mask = buts->act_mask; |
2056a782 JA |
497 | if (!bt->act_mask) |
498 | bt->act_mask = (u16) -1; | |
499 | ||
9908c309 | 500 | blk_trace_setup_lba(bt, bdev); |
2056a782 | 501 | |
d0deef5b SD |
502 | /* overwrite with user settings */ |
503 | if (buts->start_lba) | |
504 | bt->start_lba = buts->start_lba; | |
505 | if (buts->end_lba) | |
506 | bt->end_lba = buts->end_lba; | |
507 | ||
171044d4 | 508 | bt->pid = buts->pid; |
2056a782 JA |
509 | bt->trace_state = Blktrace_setup; |
510 | ||
511 | ret = -EBUSY; | |
512 | old_bt = xchg(&q->blk_trace, bt); | |
513 | if (old_bt) { | |
514 | (void) xchg(&q->blk_trace, old_bt); | |
515 | goto err; | |
516 | } | |
517 | ||
17ba97e3 | 518 | if (atomic_inc_return(&blk_probes_ref) == 1) |
cbe28296 LZ |
519 | blk_register_tracepoints(); |
520 | ||
2056a782 JA |
521 | return 0; |
522 | err: | |
ad5dd549 | 523 | blk_trace_free(bt); |
2056a782 JA |
524 | return ret; |
525 | } | |
171044d4 | 526 | |
6da127ad | 527 | int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, |
d0deef5b | 528 | struct block_device *bdev, |
6da127ad | 529 | char __user *arg) |
171044d4 AB |
530 | { |
531 | struct blk_user_trace_setup buts; | |
532 | int ret; | |
533 | ||
534 | ret = copy_from_user(&buts, arg, sizeof(buts)); | |
535 | if (ret) | |
536 | return -EFAULT; | |
537 | ||
d0deef5b | 538 | ret = do_blk_trace_setup(q, name, dev, bdev, &buts); |
171044d4 AB |
539 | if (ret) |
540 | return ret; | |
541 | ||
9a8c28c8 DM |
542 | if (copy_to_user(arg, &buts, sizeof(buts))) { |
543 | blk_trace_remove(q); | |
171044d4 | 544 | return -EFAULT; |
9a8c28c8 | 545 | } |
171044d4 AB |
546 | return 0; |
547 | } | |
6da127ad | 548 | EXPORT_SYMBOL_GPL(blk_trace_setup); |
2056a782 | 549 | |
62c2a7d9 AB |
550 | #if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64) |
551 | static int compat_blk_trace_setup(struct request_queue *q, char *name, | |
552 | dev_t dev, struct block_device *bdev, | |
553 | char __user *arg) | |
554 | { | |
555 | struct blk_user_trace_setup buts; | |
556 | struct compat_blk_user_trace_setup cbuts; | |
557 | int ret; | |
558 | ||
559 | if (copy_from_user(&cbuts, arg, sizeof(cbuts))) | |
560 | return -EFAULT; | |
561 | ||
562 | buts = (struct blk_user_trace_setup) { | |
563 | .act_mask = cbuts.act_mask, | |
564 | .buf_size = cbuts.buf_size, | |
565 | .buf_nr = cbuts.buf_nr, | |
566 | .start_lba = cbuts.start_lba, | |
567 | .end_lba = cbuts.end_lba, | |
568 | .pid = cbuts.pid, | |
569 | }; | |
570 | memcpy(&buts.name, &cbuts.name, 32); | |
571 | ||
572 | ret = do_blk_trace_setup(q, name, dev, bdev, &buts); | |
573 | if (ret) | |
574 | return ret; | |
575 | ||
576 | if (copy_to_user(arg, &buts.name, 32)) { | |
577 | blk_trace_remove(q); | |
578 | return -EFAULT; | |
579 | } | |
580 | ||
581 | return 0; | |
582 | } | |
583 | #endif | |
584 | ||
6da127ad | 585 | int blk_trace_startstop(struct request_queue *q, int start) |
2056a782 | 586 | { |
2056a782 | 587 | int ret; |
939b3669 | 588 | struct blk_trace *bt = q->blk_trace; |
2056a782 | 589 | |
939b3669 | 590 | if (bt == NULL) |
2056a782 JA |
591 | return -EINVAL; |
592 | ||
593 | /* | |
594 | * For starting a trace, we can transition from a setup or stopped | |
595 | * trace. For stopping a trace, the state must be running | |
596 | */ | |
597 | ret = -EINVAL; | |
598 | if (start) { | |
599 | if (bt->trace_state == Blktrace_setup || | |
600 | bt->trace_state == Blktrace_stopped) { | |
601 | blktrace_seq++; | |
602 | smp_mb(); | |
603 | bt->trace_state = Blktrace_running; | |
be1c6341 OK |
604 | |
605 | trace_note_time(bt); | |
2056a782 JA |
606 | ret = 0; |
607 | } | |
608 | } else { | |
609 | if (bt->trace_state == Blktrace_running) { | |
610 | bt->trace_state = Blktrace_stopped; | |
611 | relay_flush(bt->rchan); | |
612 | ret = 0; | |
613 | } | |
614 | } | |
615 | ||
616 | return ret; | |
617 | } | |
6da127ad | 618 | EXPORT_SYMBOL_GPL(blk_trace_startstop); |
2056a782 JA |
619 | |
620 | /** | |
621 | * blk_trace_ioctl: - handle the ioctls associated with tracing | |
622 | * @bdev: the block device | |
ef18012b | 623 | * @cmd: the ioctl cmd |
2056a782 JA |
624 | * @arg: the argument data, if any |
625 | * | |
626 | **/ | |
627 | int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) | |
628 | { | |
165125e1 | 629 | struct request_queue *q; |
2056a782 | 630 | int ret, start = 0; |
6da127ad | 631 | char b[BDEVNAME_SIZE]; |
2056a782 JA |
632 | |
633 | q = bdev_get_queue(bdev); | |
634 | if (!q) | |
635 | return -ENXIO; | |
636 | ||
637 | mutex_lock(&bdev->bd_mutex); | |
638 | ||
639 | switch (cmd) { | |
640 | case BLKTRACESETUP: | |
f36f21ec | 641 | bdevname(bdev, b); |
d0deef5b | 642 | ret = blk_trace_setup(q, b, bdev->bd_dev, bdev, arg); |
2056a782 | 643 | break; |
62c2a7d9 AB |
644 | #if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64) |
645 | case BLKTRACESETUP32: | |
646 | bdevname(bdev, b); | |
647 | ret = compat_blk_trace_setup(q, b, bdev->bd_dev, bdev, arg); | |
648 | break; | |
649 | #endif | |
2056a782 JA |
650 | case BLKTRACESTART: |
651 | start = 1; | |
652 | case BLKTRACESTOP: | |
653 | ret = blk_trace_startstop(q, start); | |
654 | break; | |
655 | case BLKTRACETEARDOWN: | |
656 | ret = blk_trace_remove(q); | |
657 | break; | |
658 | default: | |
659 | ret = -ENOTTY; | |
660 | break; | |
661 | } | |
662 | ||
663 | mutex_unlock(&bdev->bd_mutex); | |
664 | return ret; | |
665 | } | |
666 | ||
667 | /** | |
668 | * blk_trace_shutdown: - stop and cleanup trace structures | |
669 | * @q: the request queue associated with the device | |
670 | * | |
671 | **/ | |
165125e1 | 672 | void blk_trace_shutdown(struct request_queue *q) |
2056a782 | 673 | { |
6c5c9341 AD |
674 | if (q->blk_trace) { |
675 | blk_trace_startstop(q, 0); | |
676 | blk_trace_remove(q); | |
677 | } | |
2056a782 | 678 | } |
5f3ea37c ACM |
679 | |
680 | /* | |
681 | * blktrace probes | |
682 | */ | |
683 | ||
684 | /** | |
685 | * blk_add_trace_rq - Add a trace for a request oriented action | |
686 | * @q: queue the io is for | |
687 | * @rq: the source request | |
688 | * @what: the action | |
689 | * | |
690 | * Description: | |
691 | * Records an action against a request. Will log the bio offset + size. | |
692 | * | |
693 | **/ | |
694 | static void blk_add_trace_rq(struct request_queue *q, struct request *rq, | |
805f6b5e | 695 | u32 what) |
5f3ea37c ACM |
696 | { |
697 | struct blk_trace *bt = q->blk_trace; | |
5f3ea37c ACM |
698 | |
699 | if (likely(!bt)) | |
700 | return; | |
701 | ||
33659ebb | 702 | if (rq->cmd_type == REQ_TYPE_BLOCK_PC) { |
5f3ea37c | 703 | what |= BLK_TC_ACT(BLK_TC_PC); |
805f6b5e | 704 | __blk_add_trace(bt, 0, blk_rq_bytes(rq), rq->cmd_flags, |
2e46e8b2 | 705 | what, rq->errors, rq->cmd_len, rq->cmd); |
5f3ea37c ACM |
706 | } else { |
707 | what |= BLK_TC_ACT(BLK_TC_FS); | |
805f6b5e TM |
708 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), |
709 | rq->cmd_flags, what, rq->errors, 0, NULL); | |
5f3ea37c ACM |
710 | } |
711 | } | |
712 | ||
38516ab5 SR |
713 | static void blk_add_trace_rq_abort(void *ignore, |
714 | struct request_queue *q, struct request *rq) | |
5f3ea37c ACM |
715 | { |
716 | blk_add_trace_rq(q, rq, BLK_TA_ABORT); | |
717 | } | |
718 | ||
38516ab5 SR |
719 | static void blk_add_trace_rq_insert(void *ignore, |
720 | struct request_queue *q, struct request *rq) | |
5f3ea37c ACM |
721 | { |
722 | blk_add_trace_rq(q, rq, BLK_TA_INSERT); | |
723 | } | |
724 | ||
38516ab5 SR |
725 | static void blk_add_trace_rq_issue(void *ignore, |
726 | struct request_queue *q, struct request *rq) | |
5f3ea37c ACM |
727 | { |
728 | blk_add_trace_rq(q, rq, BLK_TA_ISSUE); | |
729 | } | |
730 | ||
38516ab5 SR |
731 | static void blk_add_trace_rq_requeue(void *ignore, |
732 | struct request_queue *q, | |
939b3669 | 733 | struct request *rq) |
5f3ea37c ACM |
734 | { |
735 | blk_add_trace_rq(q, rq, BLK_TA_REQUEUE); | |
736 | } | |
737 | ||
38516ab5 SR |
738 | static void blk_add_trace_rq_complete(void *ignore, |
739 | struct request_queue *q, | |
939b3669 | 740 | struct request *rq) |
5f3ea37c ACM |
741 | { |
742 | blk_add_trace_rq(q, rq, BLK_TA_COMPLETE); | |
743 | } | |
744 | ||
745 | /** | |
746 | * blk_add_trace_bio - Add a trace for a bio oriented action | |
747 | * @q: queue the io is for | |
748 | * @bio: the source bio | |
749 | * @what: the action | |
797a455d | 750 | * @error: error, if any |
5f3ea37c ACM |
751 | * |
752 | * Description: | |
753 | * Records an action against a bio. Will log the bio offset + size. | |
754 | * | |
755 | **/ | |
756 | static void blk_add_trace_bio(struct request_queue *q, struct bio *bio, | |
797a455d | 757 | u32 what, int error) |
5f3ea37c ACM |
758 | { |
759 | struct blk_trace *bt = q->blk_trace; | |
760 | ||
761 | if (likely(!bt)) | |
762 | return; | |
763 | ||
797a455d JA |
764 | if (!error && !bio_flagged(bio, BIO_UPTODATE)) |
765 | error = EIO; | |
766 | ||
5f3ea37c | 767 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, |
797a455d | 768 | error, 0, NULL); |
5f3ea37c ACM |
769 | } |
770 | ||
38516ab5 SR |
771 | static void blk_add_trace_bio_bounce(void *ignore, |
772 | struct request_queue *q, struct bio *bio) | |
5f3ea37c | 773 | { |
797a455d | 774 | blk_add_trace_bio(q, bio, BLK_TA_BOUNCE, 0); |
5f3ea37c ACM |
775 | } |
776 | ||
0a82a8d1 LT |
777 | static void blk_add_trace_bio_complete(void *ignore, |
778 | struct request_queue *q, struct bio *bio, | |
779 | int error) | |
5f3ea37c | 780 | { |
797a455d | 781 | blk_add_trace_bio(q, bio, BLK_TA_COMPLETE, error); |
5f3ea37c ACM |
782 | } |
783 | ||
38516ab5 SR |
784 | static void blk_add_trace_bio_backmerge(void *ignore, |
785 | struct request_queue *q, | |
8c1cf6bb | 786 | struct request *rq, |
939b3669 | 787 | struct bio *bio) |
5f3ea37c | 788 | { |
797a455d | 789 | blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE, 0); |
5f3ea37c ACM |
790 | } |
791 | ||
38516ab5 SR |
792 | static void blk_add_trace_bio_frontmerge(void *ignore, |
793 | struct request_queue *q, | |
8c1cf6bb | 794 | struct request *rq, |
939b3669 | 795 | struct bio *bio) |
5f3ea37c | 796 | { |
797a455d | 797 | blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE, 0); |
5f3ea37c ACM |
798 | } |
799 | ||
38516ab5 SR |
800 | static void blk_add_trace_bio_queue(void *ignore, |
801 | struct request_queue *q, struct bio *bio) | |
5f3ea37c | 802 | { |
797a455d | 803 | blk_add_trace_bio(q, bio, BLK_TA_QUEUE, 0); |
5f3ea37c ACM |
804 | } |
805 | ||
38516ab5 SR |
806 | static void blk_add_trace_getrq(void *ignore, |
807 | struct request_queue *q, | |
939b3669 | 808 | struct bio *bio, int rw) |
5f3ea37c ACM |
809 | { |
810 | if (bio) | |
797a455d | 811 | blk_add_trace_bio(q, bio, BLK_TA_GETRQ, 0); |
5f3ea37c ACM |
812 | else { |
813 | struct blk_trace *bt = q->blk_trace; | |
814 | ||
815 | if (bt) | |
816 | __blk_add_trace(bt, 0, 0, rw, BLK_TA_GETRQ, 0, 0, NULL); | |
817 | } | |
818 | } | |
819 | ||
820 | ||
38516ab5 SR |
821 | static void blk_add_trace_sleeprq(void *ignore, |
822 | struct request_queue *q, | |
939b3669 | 823 | struct bio *bio, int rw) |
5f3ea37c ACM |
824 | { |
825 | if (bio) | |
797a455d | 826 | blk_add_trace_bio(q, bio, BLK_TA_SLEEPRQ, 0); |
5f3ea37c ACM |
827 | else { |
828 | struct blk_trace *bt = q->blk_trace; | |
829 | ||
830 | if (bt) | |
939b3669 ACM |
831 | __blk_add_trace(bt, 0, 0, rw, BLK_TA_SLEEPRQ, |
832 | 0, 0, NULL); | |
5f3ea37c ACM |
833 | } |
834 | } | |
835 | ||
38516ab5 | 836 | static void blk_add_trace_plug(void *ignore, struct request_queue *q) |
5f3ea37c ACM |
837 | { |
838 | struct blk_trace *bt = q->blk_trace; | |
839 | ||
840 | if (bt) | |
841 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_PLUG, 0, 0, NULL); | |
842 | } | |
843 | ||
49cac01e JA |
844 | static void blk_add_trace_unplug(void *ignore, struct request_queue *q, |
845 | unsigned int depth, bool explicit) | |
5f3ea37c ACM |
846 | { |
847 | struct blk_trace *bt = q->blk_trace; | |
848 | ||
849 | if (bt) { | |
94b5eb28 | 850 | __be64 rpdu = cpu_to_be64(depth); |
49cac01e | 851 | u32 what; |
5f3ea37c | 852 | |
49cac01e JA |
853 | if (explicit) |
854 | what = BLK_TA_UNPLUG_IO; | |
855 | else | |
856 | what = BLK_TA_UNPLUG_TIMER; | |
857 | ||
858 | __blk_add_trace(bt, 0, 0, 0, what, 0, sizeof(rpdu), &rpdu); | |
5f3ea37c ACM |
859 | } |
860 | } | |
861 | ||
38516ab5 SR |
862 | static void blk_add_trace_split(void *ignore, |
863 | struct request_queue *q, struct bio *bio, | |
5f3ea37c ACM |
864 | unsigned int pdu) |
865 | { | |
866 | struct blk_trace *bt = q->blk_trace; | |
867 | ||
868 | if (bt) { | |
869 | __be64 rpdu = cpu_to_be64(pdu); | |
870 | ||
871 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, | |
872 | BLK_TA_SPLIT, !bio_flagged(bio, BIO_UPTODATE), | |
873 | sizeof(rpdu), &rpdu); | |
874 | } | |
875 | } | |
876 | ||
877 | /** | |
d07335e5 | 878 | * blk_add_trace_bio_remap - Add a trace for a bio-remap operation |
546cf44a | 879 | * @ignore: trace callback data parameter (not used) |
5f3ea37c ACM |
880 | * @q: queue the io is for |
881 | * @bio: the source bio | |
882 | * @dev: target device | |
a42aaa3b | 883 | * @from: source sector |
5f3ea37c ACM |
884 | * |
885 | * Description: | |
886 | * Device mapper or raid target sometimes need to split a bio because | |
887 | * it spans a stripe (or similar). Add a trace for that action. | |
888 | * | |
889 | **/ | |
d07335e5 MS |
890 | static void blk_add_trace_bio_remap(void *ignore, |
891 | struct request_queue *q, struct bio *bio, | |
892 | dev_t dev, sector_t from) | |
5f3ea37c ACM |
893 | { |
894 | struct blk_trace *bt = q->blk_trace; | |
895 | struct blk_io_trace_remap r; | |
896 | ||
897 | if (likely(!bt)) | |
898 | return; | |
899 | ||
a42aaa3b AB |
900 | r.device_from = cpu_to_be32(dev); |
901 | r.device_to = cpu_to_be32(bio->bi_bdev->bd_dev); | |
902 | r.sector_from = cpu_to_be64(from); | |
5f3ea37c | 903 | |
22a7c31a AB |
904 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, |
905 | BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), | |
906 | sizeof(r), &r); | |
5f3ea37c ACM |
907 | } |
908 | ||
b0da3f0d JN |
909 | /** |
910 | * blk_add_trace_rq_remap - Add a trace for a request-remap operation | |
546cf44a | 911 | * @ignore: trace callback data parameter (not used) |
b0da3f0d JN |
912 | * @q: queue the io is for |
913 | * @rq: the source request | |
914 | * @dev: target device | |
915 | * @from: source sector | |
916 | * | |
917 | * Description: | |
918 | * Device mapper remaps request to other devices. | |
919 | * Add a trace for that action. | |
920 | * | |
921 | **/ | |
38516ab5 SR |
922 | static void blk_add_trace_rq_remap(void *ignore, |
923 | struct request_queue *q, | |
b0da3f0d JN |
924 | struct request *rq, dev_t dev, |
925 | sector_t from) | |
926 | { | |
927 | struct blk_trace *bt = q->blk_trace; | |
928 | struct blk_io_trace_remap r; | |
929 | ||
930 | if (likely(!bt)) | |
931 | return; | |
932 | ||
933 | r.device_from = cpu_to_be32(dev); | |
934 | r.device_to = cpu_to_be32(disk_devt(rq->rq_disk)); | |
935 | r.sector_from = cpu_to_be64(from); | |
936 | ||
937 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), | |
938 | rq_data_dir(rq), BLK_TA_REMAP, !!rq->errors, | |
939 | sizeof(r), &r); | |
940 | } | |
941 | ||
5f3ea37c ACM |
942 | /** |
943 | * blk_add_driver_data - Add binary message with driver-specific data | |
944 | * @q: queue the io is for | |
945 | * @rq: io request | |
946 | * @data: driver-specific data | |
947 | * @len: length of driver-specific data | |
948 | * | |
949 | * Description: | |
950 | * Some drivers might want to write driver-specific data per request. | |
951 | * | |
952 | **/ | |
953 | void blk_add_driver_data(struct request_queue *q, | |
954 | struct request *rq, | |
955 | void *data, size_t len) | |
956 | { | |
957 | struct blk_trace *bt = q->blk_trace; | |
958 | ||
959 | if (likely(!bt)) | |
960 | return; | |
961 | ||
33659ebb | 962 | if (rq->cmd_type == REQ_TYPE_BLOCK_PC) |
2e46e8b2 TH |
963 | __blk_add_trace(bt, 0, blk_rq_bytes(rq), 0, |
964 | BLK_TA_DRV_DATA, rq->errors, len, data); | |
5f3ea37c | 965 | else |
2e46e8b2 TH |
966 | __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), 0, |
967 | BLK_TA_DRV_DATA, rq->errors, len, data); | |
5f3ea37c ACM |
968 | } |
969 | EXPORT_SYMBOL_GPL(blk_add_driver_data); | |
970 | ||
3c289ba7 | 971 | static void blk_register_tracepoints(void) |
5f3ea37c ACM |
972 | { |
973 | int ret; | |
974 | ||
38516ab5 | 975 | ret = register_trace_block_rq_abort(blk_add_trace_rq_abort, NULL); |
5f3ea37c | 976 | WARN_ON(ret); |
38516ab5 | 977 | ret = register_trace_block_rq_insert(blk_add_trace_rq_insert, NULL); |
5f3ea37c | 978 | WARN_ON(ret); |
38516ab5 | 979 | ret = register_trace_block_rq_issue(blk_add_trace_rq_issue, NULL); |
5f3ea37c | 980 | WARN_ON(ret); |
38516ab5 | 981 | ret = register_trace_block_rq_requeue(blk_add_trace_rq_requeue, NULL); |
5f3ea37c | 982 | WARN_ON(ret); |
38516ab5 | 983 | ret = register_trace_block_rq_complete(blk_add_trace_rq_complete, NULL); |
5f3ea37c | 984 | WARN_ON(ret); |
38516ab5 | 985 | ret = register_trace_block_bio_bounce(blk_add_trace_bio_bounce, NULL); |
5f3ea37c | 986 | WARN_ON(ret); |
38516ab5 | 987 | ret = register_trace_block_bio_complete(blk_add_trace_bio_complete, NULL); |
5f3ea37c | 988 | WARN_ON(ret); |
38516ab5 | 989 | ret = register_trace_block_bio_backmerge(blk_add_trace_bio_backmerge, NULL); |
5f3ea37c | 990 | WARN_ON(ret); |
38516ab5 | 991 | ret = register_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge, NULL); |
5f3ea37c | 992 | WARN_ON(ret); |
38516ab5 | 993 | ret = register_trace_block_bio_queue(blk_add_trace_bio_queue, NULL); |
5f3ea37c | 994 | WARN_ON(ret); |
38516ab5 | 995 | ret = register_trace_block_getrq(blk_add_trace_getrq, NULL); |
5f3ea37c | 996 | WARN_ON(ret); |
38516ab5 | 997 | ret = register_trace_block_sleeprq(blk_add_trace_sleeprq, NULL); |
5f3ea37c | 998 | WARN_ON(ret); |
38516ab5 | 999 | ret = register_trace_block_plug(blk_add_trace_plug, NULL); |
5f3ea37c | 1000 | WARN_ON(ret); |
49cac01e | 1001 | ret = register_trace_block_unplug(blk_add_trace_unplug, NULL); |
5f3ea37c | 1002 | WARN_ON(ret); |
38516ab5 | 1003 | ret = register_trace_block_split(blk_add_trace_split, NULL); |
5f3ea37c | 1004 | WARN_ON(ret); |
d07335e5 | 1005 | ret = register_trace_block_bio_remap(blk_add_trace_bio_remap, NULL); |
5f3ea37c | 1006 | WARN_ON(ret); |
38516ab5 | 1007 | ret = register_trace_block_rq_remap(blk_add_trace_rq_remap, NULL); |
b0da3f0d | 1008 | WARN_ON(ret); |
5f3ea37c ACM |
1009 | } |
1010 | ||
1011 | static void blk_unregister_tracepoints(void) | |
1012 | { | |
38516ab5 | 1013 | unregister_trace_block_rq_remap(blk_add_trace_rq_remap, NULL); |
d07335e5 | 1014 | unregister_trace_block_bio_remap(blk_add_trace_bio_remap, NULL); |
38516ab5 | 1015 | unregister_trace_block_split(blk_add_trace_split, NULL); |
49cac01e | 1016 | unregister_trace_block_unplug(blk_add_trace_unplug, NULL); |
38516ab5 SR |
1017 | unregister_trace_block_plug(blk_add_trace_plug, NULL); |
1018 | unregister_trace_block_sleeprq(blk_add_trace_sleeprq, NULL); | |
1019 | unregister_trace_block_getrq(blk_add_trace_getrq, NULL); | |
1020 | unregister_trace_block_bio_queue(blk_add_trace_bio_queue, NULL); | |
1021 | unregister_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge, NULL); | |
1022 | unregister_trace_block_bio_backmerge(blk_add_trace_bio_backmerge, NULL); | |
1023 | unregister_trace_block_bio_complete(blk_add_trace_bio_complete, NULL); | |
1024 | unregister_trace_block_bio_bounce(blk_add_trace_bio_bounce, NULL); | |
1025 | unregister_trace_block_rq_complete(blk_add_trace_rq_complete, NULL); | |
1026 | unregister_trace_block_rq_requeue(blk_add_trace_rq_requeue, NULL); | |
1027 | unregister_trace_block_rq_issue(blk_add_trace_rq_issue, NULL); | |
1028 | unregister_trace_block_rq_insert(blk_add_trace_rq_insert, NULL); | |
1029 | unregister_trace_block_rq_abort(blk_add_trace_rq_abort, NULL); | |
5f3ea37c ACM |
1030 | |
1031 | tracepoint_synchronize_unregister(); | |
1032 | } | |
c71a8961 ACM |
1033 | |
1034 | /* | |
1035 | * struct blk_io_tracer formatting routines | |
1036 | */ | |
1037 | ||
1038 | static void fill_rwbs(char *rwbs, const struct blk_io_trace *t) | |
1039 | { | |
157f9c00 | 1040 | int i = 0; |
65796348 | 1041 | int tc = t->action >> BLK_TC_SHIFT; |
157f9c00 | 1042 | |
18cea459 LZ |
1043 | if (t->action == BLK_TN_MESSAGE) { |
1044 | rwbs[i++] = 'N'; | |
1045 | goto out; | |
1046 | } | |
1047 | ||
c09c47ca NK |
1048 | if (tc & BLK_TC_FLUSH) |
1049 | rwbs[i++] = 'F'; | |
1050 | ||
65796348 | 1051 | if (tc & BLK_TC_DISCARD) |
157f9c00 | 1052 | rwbs[i++] = 'D'; |
65796348 | 1053 | else if (tc & BLK_TC_WRITE) |
157f9c00 ACM |
1054 | rwbs[i++] = 'W'; |
1055 | else if (t->bytes) | |
1056 | rwbs[i++] = 'R'; | |
1057 | else | |
1058 | rwbs[i++] = 'N'; | |
1059 | ||
c09c47ca NK |
1060 | if (tc & BLK_TC_FUA) |
1061 | rwbs[i++] = 'F'; | |
65796348 | 1062 | if (tc & BLK_TC_AHEAD) |
157f9c00 | 1063 | rwbs[i++] = 'A'; |
65796348 | 1064 | if (tc & BLK_TC_SYNC) |
157f9c00 | 1065 | rwbs[i++] = 'S'; |
65796348 | 1066 | if (tc & BLK_TC_META) |
157f9c00 | 1067 | rwbs[i++] = 'M'; |
18cea459 | 1068 | out: |
157f9c00 | 1069 | rwbs[i] = '\0'; |
c71a8961 ACM |
1070 | } |
1071 | ||
1072 | static inline | |
1073 | const struct blk_io_trace *te_blk_io_trace(const struct trace_entry *ent) | |
1074 | { | |
1075 | return (const struct blk_io_trace *)ent; | |
1076 | } | |
1077 | ||
1078 | static inline const void *pdu_start(const struct trace_entry *ent) | |
1079 | { | |
1080 | return te_blk_io_trace(ent) + 1; | |
1081 | } | |
1082 | ||
66de7792 LZ |
1083 | static inline u32 t_action(const struct trace_entry *ent) |
1084 | { | |
1085 | return te_blk_io_trace(ent)->action; | |
1086 | } | |
1087 | ||
1088 | static inline u32 t_bytes(const struct trace_entry *ent) | |
1089 | { | |
1090 | return te_blk_io_trace(ent)->bytes; | |
1091 | } | |
1092 | ||
c71a8961 ACM |
1093 | static inline u32 t_sec(const struct trace_entry *ent) |
1094 | { | |
1095 | return te_blk_io_trace(ent)->bytes >> 9; | |
1096 | } | |
1097 | ||
1098 | static inline unsigned long long t_sector(const struct trace_entry *ent) | |
1099 | { | |
1100 | return te_blk_io_trace(ent)->sector; | |
1101 | } | |
1102 | ||
1103 | static inline __u16 t_error(const struct trace_entry *ent) | |
1104 | { | |
e0dc81be | 1105 | return te_blk_io_trace(ent)->error; |
c71a8961 ACM |
1106 | } |
1107 | ||
1108 | static __u64 get_pdu_int(const struct trace_entry *ent) | |
1109 | { | |
1110 | const __u64 *val = pdu_start(ent); | |
1111 | return be64_to_cpu(*val); | |
1112 | } | |
1113 | ||
1114 | static void get_pdu_remap(const struct trace_entry *ent, | |
1115 | struct blk_io_trace_remap *r) | |
1116 | { | |
1117 | const struct blk_io_trace_remap *__r = pdu_start(ent); | |
a42aaa3b | 1118 | __u64 sector_from = __r->sector_from; |
c71a8961 | 1119 | |
c71a8961 | 1120 | r->device_from = be32_to_cpu(__r->device_from); |
a42aaa3b AB |
1121 | r->device_to = be32_to_cpu(__r->device_to); |
1122 | r->sector_from = be64_to_cpu(sector_from); | |
c71a8961 ACM |
1123 | } |
1124 | ||
b6a4b0c3 LZ |
1125 | typedef int (blk_log_action_t) (struct trace_iterator *iter, const char *act); |
1126 | ||
1127 | static int blk_log_action_classic(struct trace_iterator *iter, const char *act) | |
c71a8961 | 1128 | { |
c09c47ca | 1129 | char rwbs[RWBS_LEN]; |
35ac51bf LZ |
1130 | unsigned long long ts = iter->ts; |
1131 | unsigned long nsec_rem = do_div(ts, NSEC_PER_SEC); | |
c71a8961 | 1132 | unsigned secs = (unsigned long)ts; |
b6a4b0c3 | 1133 | const struct blk_io_trace *t = te_blk_io_trace(iter->ent); |
c71a8961 ACM |
1134 | |
1135 | fill_rwbs(rwbs, t); | |
1136 | ||
1137 | return trace_seq_printf(&iter->seq, | |
35ac51bf | 1138 | "%3d,%-3d %2d %5d.%09lu %5u %2s %3s ", |
c71a8961 | 1139 | MAJOR(t->device), MINOR(t->device), iter->cpu, |
b6a4b0c3 | 1140 | secs, nsec_rem, iter->ent->pid, act, rwbs); |
c71a8961 ACM |
1141 | } |
1142 | ||
b6a4b0c3 | 1143 | static int blk_log_action(struct trace_iterator *iter, const char *act) |
c71a8961 | 1144 | { |
c09c47ca | 1145 | char rwbs[RWBS_LEN]; |
b6a4b0c3 LZ |
1146 | const struct blk_io_trace *t = te_blk_io_trace(iter->ent); |
1147 | ||
c71a8961 | 1148 | fill_rwbs(rwbs, t); |
b6a4b0c3 | 1149 | return trace_seq_printf(&iter->seq, "%3d,%-3d %2s %3s ", |
c71a8961 ACM |
1150 | MAJOR(t->device), MINOR(t->device), act, rwbs); |
1151 | } | |
1152 | ||
66de7792 LZ |
1153 | static int blk_log_dump_pdu(struct trace_seq *s, const struct trace_entry *ent) |
1154 | { | |
04986257 | 1155 | const unsigned char *pdu_buf; |
66de7792 LZ |
1156 | int pdu_len; |
1157 | int i, end, ret; | |
1158 | ||
1159 | pdu_buf = pdu_start(ent); | |
1160 | pdu_len = te_blk_io_trace(ent)->pdu_len; | |
1161 | ||
1162 | if (!pdu_len) | |
1163 | return 1; | |
1164 | ||
1165 | /* find the last zero that needs to be printed */ | |
1166 | for (end = pdu_len - 1; end >= 0; end--) | |
1167 | if (pdu_buf[end]) | |
1168 | break; | |
1169 | end++; | |
1170 | ||
1171 | if (!trace_seq_putc(s, '(')) | |
1172 | return 0; | |
1173 | ||
1174 | for (i = 0; i < pdu_len; i++) { | |
1175 | ||
1176 | ret = trace_seq_printf(s, "%s%02x", | |
1177 | i == 0 ? "" : " ", pdu_buf[i]); | |
1178 | if (!ret) | |
1179 | return ret; | |
1180 | ||
1181 | /* | |
1182 | * stop when the rest is just zeroes and indicate so | |
1183 | * with a ".." appended | |
1184 | */ | |
1185 | if (i == end && end != pdu_len - 1) | |
1186 | return trace_seq_puts(s, " ..) "); | |
1187 | } | |
1188 | ||
1189 | return trace_seq_puts(s, ") "); | |
1190 | } | |
1191 | ||
c71a8961 ACM |
1192 | static int blk_log_generic(struct trace_seq *s, const struct trace_entry *ent) |
1193 | { | |
4ca53085 SR |
1194 | char cmd[TASK_COMM_LEN]; |
1195 | ||
1196 | trace_find_cmdline(ent->pid, cmd); | |
c71a8961 | 1197 | |
66de7792 LZ |
1198 | if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { |
1199 | int ret; | |
1200 | ||
1201 | ret = trace_seq_printf(s, "%u ", t_bytes(ent)); | |
1202 | if (!ret) | |
1203 | return 0; | |
1204 | ret = blk_log_dump_pdu(s, ent); | |
1205 | if (!ret) | |
1206 | return 0; | |
1207 | return trace_seq_printf(s, "[%s]\n", cmd); | |
1208 | } else { | |
1209 | if (t_sec(ent)) | |
1210 | return trace_seq_printf(s, "%llu + %u [%s]\n", | |
1211 | t_sector(ent), t_sec(ent), cmd); | |
1212 | return trace_seq_printf(s, "[%s]\n", cmd); | |
1213 | } | |
c71a8961 ACM |
1214 | } |
1215 | ||
157f9c00 ACM |
1216 | static int blk_log_with_error(struct trace_seq *s, |
1217 | const struct trace_entry *ent) | |
c71a8961 | 1218 | { |
66de7792 LZ |
1219 | if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) { |
1220 | int ret; | |
1221 | ||
1222 | ret = blk_log_dump_pdu(s, ent); | |
1223 | if (ret) | |
1224 | return trace_seq_printf(s, "[%d]\n", t_error(ent)); | |
1225 | return 0; | |
1226 | } else { | |
1227 | if (t_sec(ent)) | |
1228 | return trace_seq_printf(s, "%llu + %u [%d]\n", | |
1229 | t_sector(ent), | |
1230 | t_sec(ent), t_error(ent)); | |
1231 | return trace_seq_printf(s, "%llu [%d]\n", | |
1232 | t_sector(ent), t_error(ent)); | |
1233 | } | |
c71a8961 ACM |
1234 | } |
1235 | ||
1236 | static int blk_log_remap(struct trace_seq *s, const struct trace_entry *ent) | |
1237 | { | |
a42aaa3b | 1238 | struct blk_io_trace_remap r = { .device_from = 0, }; |
c71a8961 ACM |
1239 | |
1240 | get_pdu_remap(ent, &r); | |
1241 | return trace_seq_printf(s, "%llu + %u <- (%d,%d) %llu\n", | |
a42aaa3b AB |
1242 | t_sector(ent), t_sec(ent), |
1243 | MAJOR(r.device_from), MINOR(r.device_from), | |
1244 | (unsigned long long)r.sector_from); | |
c71a8961 ACM |
1245 | } |
1246 | ||
1247 | static int blk_log_plug(struct trace_seq *s, const struct trace_entry *ent) | |
1248 | { | |
4ca53085 SR |
1249 | char cmd[TASK_COMM_LEN]; |
1250 | ||
1251 | trace_find_cmdline(ent->pid, cmd); | |
1252 | ||
1253 | return trace_seq_printf(s, "[%s]\n", cmd); | |
c71a8961 ACM |
1254 | } |
1255 | ||
1256 | static int blk_log_unplug(struct trace_seq *s, const struct trace_entry *ent) | |
1257 | { | |
4ca53085 SR |
1258 | char cmd[TASK_COMM_LEN]; |
1259 | ||
1260 | trace_find_cmdline(ent->pid, cmd); | |
1261 | ||
1262 | return trace_seq_printf(s, "[%s] %llu\n", cmd, get_pdu_int(ent)); | |
c71a8961 ACM |
1263 | } |
1264 | ||
1265 | static int blk_log_split(struct trace_seq *s, const struct trace_entry *ent) | |
1266 | { | |
4ca53085 SR |
1267 | char cmd[TASK_COMM_LEN]; |
1268 | ||
1269 | trace_find_cmdline(ent->pid, cmd); | |
1270 | ||
c71a8961 | 1271 | return trace_seq_printf(s, "%llu / %llu [%s]\n", t_sector(ent), |
4ca53085 | 1272 | get_pdu_int(ent), cmd); |
c71a8961 ACM |
1273 | } |
1274 | ||
18cea459 LZ |
1275 | static int blk_log_msg(struct trace_seq *s, const struct trace_entry *ent) |
1276 | { | |
1277 | int ret; | |
1278 | const struct blk_io_trace *t = te_blk_io_trace(ent); | |
1279 | ||
1280 | ret = trace_seq_putmem(s, t + 1, t->pdu_len); | |
1281 | if (ret) | |
1282 | return trace_seq_putc(s, '\n'); | |
1283 | return ret; | |
1284 | } | |
1285 | ||
c71a8961 ACM |
1286 | /* |
1287 | * struct tracer operations | |
1288 | */ | |
1289 | ||
1290 | static void blk_tracer_print_header(struct seq_file *m) | |
1291 | { | |
1292 | if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) | |
1293 | return; | |
1294 | seq_puts(m, "# DEV CPU TIMESTAMP PID ACT FLG\n" | |
1295 | "# | | | | | |\n"); | |
1296 | } | |
1297 | ||
1298 | static void blk_tracer_start(struct trace_array *tr) | |
1299 | { | |
ad5dd549 | 1300 | blk_tracer_enabled = true; |
c71a8961 ACM |
1301 | } |
1302 | ||
1303 | static int blk_tracer_init(struct trace_array *tr) | |
1304 | { | |
1305 | blk_tr = tr; | |
1306 | blk_tracer_start(tr); | |
c71a8961 ACM |
1307 | return 0; |
1308 | } | |
1309 | ||
1310 | static void blk_tracer_stop(struct trace_array *tr) | |
1311 | { | |
ad5dd549 | 1312 | blk_tracer_enabled = false; |
c71a8961 ACM |
1313 | } |
1314 | ||
1315 | static void blk_tracer_reset(struct trace_array *tr) | |
1316 | { | |
c71a8961 ACM |
1317 | blk_tracer_stop(tr); |
1318 | } | |
1319 | ||
e4955c99 | 1320 | static const struct { |
c71a8961 | 1321 | const char *act[2]; |
ef18012b | 1322 | int (*print)(struct trace_seq *s, const struct trace_entry *ent); |
e4955c99 | 1323 | } what2act[] = { |
ef18012b | 1324 | [__BLK_TA_QUEUE] = {{ "Q", "queue" }, blk_log_generic }, |
c71a8961 ACM |
1325 | [__BLK_TA_BACKMERGE] = {{ "M", "backmerge" }, blk_log_generic }, |
1326 | [__BLK_TA_FRONTMERGE] = {{ "F", "frontmerge" }, blk_log_generic }, | |
1327 | [__BLK_TA_GETRQ] = {{ "G", "getrq" }, blk_log_generic }, | |
1328 | [__BLK_TA_SLEEPRQ] = {{ "S", "sleeprq" }, blk_log_generic }, | |
1329 | [__BLK_TA_REQUEUE] = {{ "R", "requeue" }, blk_log_with_error }, | |
1330 | [__BLK_TA_ISSUE] = {{ "D", "issue" }, blk_log_generic }, | |
1331 | [__BLK_TA_COMPLETE] = {{ "C", "complete" }, blk_log_with_error }, | |
1332 | [__BLK_TA_PLUG] = {{ "P", "plug" }, blk_log_plug }, | |
1333 | [__BLK_TA_UNPLUG_IO] = {{ "U", "unplug_io" }, blk_log_unplug }, | |
49cac01e | 1334 | [__BLK_TA_UNPLUG_TIMER] = {{ "UT", "unplug_timer" }, blk_log_unplug }, |
c71a8961 ACM |
1335 | [__BLK_TA_INSERT] = {{ "I", "insert" }, blk_log_generic }, |
1336 | [__BLK_TA_SPLIT] = {{ "X", "split" }, blk_log_split }, | |
1337 | [__BLK_TA_BOUNCE] = {{ "B", "bounce" }, blk_log_generic }, | |
1338 | [__BLK_TA_REMAP] = {{ "A", "remap" }, blk_log_remap }, | |
1339 | }; | |
1340 | ||
b6a4b0c3 LZ |
1341 | static enum print_line_t print_one_line(struct trace_iterator *iter, |
1342 | bool classic) | |
c71a8961 | 1343 | { |
2c9b238e | 1344 | struct trace_seq *s = &iter->seq; |
b6a4b0c3 LZ |
1345 | const struct blk_io_trace *t; |
1346 | u16 what; | |
c71a8961 | 1347 | int ret; |
b6a4b0c3 LZ |
1348 | bool long_act; |
1349 | blk_log_action_t *log_action; | |
c71a8961 | 1350 | |
b6a4b0c3 LZ |
1351 | t = te_blk_io_trace(iter->ent); |
1352 | what = t->action & ((1 << BLK_TC_SHIFT) - 1); | |
1353 | long_act = !!(trace_flags & TRACE_ITER_VERBOSE); | |
1354 | log_action = classic ? &blk_log_action_classic : &blk_log_action; | |
08a06b83 | 1355 | |
18cea459 LZ |
1356 | if (t->action == BLK_TN_MESSAGE) { |
1357 | ret = log_action(iter, long_act ? "message" : "m"); | |
1358 | if (ret) | |
1359 | ret = blk_log_msg(s, iter->ent); | |
1360 | goto out; | |
1361 | } | |
1362 | ||
eb08f8eb | 1363 | if (unlikely(what == 0 || what >= ARRAY_SIZE(what2act))) |
b78825d6 | 1364 | ret = trace_seq_printf(s, "Unknown action %x\n", what); |
c71a8961 | 1365 | else { |
b6a4b0c3 | 1366 | ret = log_action(iter, what2act[what].act[long_act]); |
c71a8961 | 1367 | if (ret) |
2c9b238e | 1368 | ret = what2act[what].print(s, iter->ent); |
c71a8961 | 1369 | } |
18cea459 | 1370 | out: |
c71a8961 ACM |
1371 | return ret ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; |
1372 | } | |
1373 | ||
b6a4b0c3 | 1374 | static enum print_line_t blk_trace_event_print(struct trace_iterator *iter, |
a9a57763 | 1375 | int flags, struct trace_event *event) |
b6a4b0c3 | 1376 | { |
b6a4b0c3 LZ |
1377 | return print_one_line(iter, false); |
1378 | } | |
1379 | ||
08a06b83 ACM |
1380 | static int blk_trace_synthesize_old_trace(struct trace_iterator *iter) |
1381 | { | |
1382 | struct trace_seq *s = &iter->seq; | |
1383 | struct blk_io_trace *t = (struct blk_io_trace *)iter->ent; | |
1384 | const int offset = offsetof(struct blk_io_trace, sector); | |
1385 | struct blk_io_trace old = { | |
1386 | .magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION, | |
6c051ce0 | 1387 | .time = iter->ts, |
08a06b83 ACM |
1388 | }; |
1389 | ||
1390 | if (!trace_seq_putmem(s, &old, offset)) | |
1391 | return 0; | |
1392 | return trace_seq_putmem(s, &t->sector, | |
1393 | sizeof(old) - offset + t->pdu_len); | |
1394 | } | |
1395 | ||
ae7462b4 | 1396 | static enum print_line_t |
a9a57763 SR |
1397 | blk_trace_event_print_binary(struct trace_iterator *iter, int flags, |
1398 | struct trace_event *event) | |
08a06b83 ACM |
1399 | { |
1400 | return blk_trace_synthesize_old_trace(iter) ? | |
1401 | TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE; | |
1402 | } | |
1403 | ||
c71a8961 ACM |
1404 | static enum print_line_t blk_tracer_print_line(struct trace_iterator *iter) |
1405 | { | |
c71a8961 ACM |
1406 | if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC)) |
1407 | return TRACE_TYPE_UNHANDLED; | |
1408 | ||
b6a4b0c3 | 1409 | return print_one_line(iter, true); |
c71a8961 ACM |
1410 | } |
1411 | ||
f3948f88 LZ |
1412 | static int blk_tracer_set_flag(u32 old_flags, u32 bit, int set) |
1413 | { | |
1414 | /* don't output context-info for blk_classic output */ | |
1415 | if (bit == TRACE_BLK_OPT_CLASSIC) { | |
1416 | if (set) | |
1417 | trace_flags &= ~TRACE_ITER_CONTEXT_INFO; | |
1418 | else | |
1419 | trace_flags |= TRACE_ITER_CONTEXT_INFO; | |
1420 | } | |
1421 | return 0; | |
1422 | } | |
1423 | ||
c71a8961 ACM |
1424 | static struct tracer blk_tracer __read_mostly = { |
1425 | .name = "blk", | |
1426 | .init = blk_tracer_init, | |
1427 | .reset = blk_tracer_reset, | |
1428 | .start = blk_tracer_start, | |
1429 | .stop = blk_tracer_stop, | |
1430 | .print_header = blk_tracer_print_header, | |
1431 | .print_line = blk_tracer_print_line, | |
1432 | .flags = &blk_tracer_flags, | |
f3948f88 | 1433 | .set_flag = blk_tracer_set_flag, |
c71a8961 ACM |
1434 | }; |
1435 | ||
a9a57763 | 1436 | static struct trace_event_functions trace_blk_event_funcs = { |
c71a8961 | 1437 | .trace = blk_trace_event_print, |
08a06b83 | 1438 | .binary = blk_trace_event_print_binary, |
c71a8961 ACM |
1439 | }; |
1440 | ||
a9a57763 SR |
1441 | static struct trace_event trace_blk_event = { |
1442 | .type = TRACE_BLK, | |
1443 | .funcs = &trace_blk_event_funcs, | |
1444 | }; | |
1445 | ||
c71a8961 ACM |
1446 | static int __init init_blk_tracer(void) |
1447 | { | |
1448 | if (!register_ftrace_event(&trace_blk_event)) { | |
1449 | pr_warning("Warning: could not register block events\n"); | |
1450 | return 1; | |
1451 | } | |
1452 | ||
1453 | if (register_tracer(&blk_tracer) != 0) { | |
1454 | pr_warning("Warning: could not register the block tracer\n"); | |
1455 | unregister_ftrace_event(&trace_blk_event); | |
1456 | return 1; | |
1457 | } | |
1458 | ||
1459 | return 0; | |
1460 | } | |
1461 | ||
1462 | device_initcall(init_blk_tracer); | |
1463 | ||
1464 | static int blk_trace_remove_queue(struct request_queue *q) | |
1465 | { | |
1466 | struct blk_trace *bt; | |
1467 | ||
1468 | bt = xchg(&q->blk_trace, NULL); | |
1469 | if (bt == NULL) | |
1470 | return -EINVAL; | |
1471 | ||
17ba97e3 LZ |
1472 | if (atomic_dec_and_test(&blk_probes_ref)) |
1473 | blk_unregister_tracepoints(); | |
1474 | ||
ad5dd549 | 1475 | blk_trace_free(bt); |
c71a8961 ACM |
1476 | return 0; |
1477 | } | |
1478 | ||
1479 | /* | |
1480 | * Setup everything required to start tracing | |
1481 | */ | |
9908c309 LZ |
1482 | static int blk_trace_setup_queue(struct request_queue *q, |
1483 | struct block_device *bdev) | |
c71a8961 ACM |
1484 | { |
1485 | struct blk_trace *old_bt, *bt = NULL; | |
18cea459 | 1486 | int ret = -ENOMEM; |
c71a8961 | 1487 | |
c71a8961 ACM |
1488 | bt = kzalloc(sizeof(*bt), GFP_KERNEL); |
1489 | if (!bt) | |
15152e44 | 1490 | return -ENOMEM; |
c71a8961 | 1491 | |
18cea459 LZ |
1492 | bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char)); |
1493 | if (!bt->msg_data) | |
1494 | goto free_bt; | |
1495 | ||
9908c309 | 1496 | bt->dev = bdev->bd_dev; |
c71a8961 | 1497 | bt->act_mask = (u16)-1; |
9908c309 LZ |
1498 | |
1499 | blk_trace_setup_lba(bt, bdev); | |
c71a8961 ACM |
1500 | |
1501 | old_bt = xchg(&q->blk_trace, bt); | |
1502 | if (old_bt != NULL) { | |
1503 | (void)xchg(&q->blk_trace, old_bt); | |
18cea459 LZ |
1504 | ret = -EBUSY; |
1505 | goto free_bt; | |
c71a8961 | 1506 | } |
15152e44 | 1507 | |
17ba97e3 LZ |
1508 | if (atomic_inc_return(&blk_probes_ref) == 1) |
1509 | blk_register_tracepoints(); | |
c71a8961 | 1510 | return 0; |
18cea459 LZ |
1511 | |
1512 | free_bt: | |
1513 | blk_trace_free(bt); | |
1514 | return ret; | |
c71a8961 ACM |
1515 | } |
1516 | ||
1517 | /* | |
1518 | * sysfs interface to enable and configure tracing | |
1519 | */ | |
1520 | ||
c71a8961 ACM |
1521 | static ssize_t sysfs_blk_trace_attr_show(struct device *dev, |
1522 | struct device_attribute *attr, | |
1523 | char *buf); | |
1524 | static ssize_t sysfs_blk_trace_attr_store(struct device *dev, | |
1525 | struct device_attribute *attr, | |
1526 | const char *buf, size_t count); | |
1527 | #define BLK_TRACE_DEVICE_ATTR(_name) \ | |
1528 | DEVICE_ATTR(_name, S_IRUGO | S_IWUSR, \ | |
1529 | sysfs_blk_trace_attr_show, \ | |
1530 | sysfs_blk_trace_attr_store) | |
1531 | ||
cd649b8b | 1532 | static BLK_TRACE_DEVICE_ATTR(enable); |
c71a8961 ACM |
1533 | static BLK_TRACE_DEVICE_ATTR(act_mask); |
1534 | static BLK_TRACE_DEVICE_ATTR(pid); | |
1535 | static BLK_TRACE_DEVICE_ATTR(start_lba); | |
1536 | static BLK_TRACE_DEVICE_ATTR(end_lba); | |
1537 | ||
1538 | static struct attribute *blk_trace_attrs[] = { | |
1539 | &dev_attr_enable.attr, | |
1540 | &dev_attr_act_mask.attr, | |
1541 | &dev_attr_pid.attr, | |
1542 | &dev_attr_start_lba.attr, | |
1543 | &dev_attr_end_lba.attr, | |
1544 | NULL | |
1545 | }; | |
1546 | ||
1547 | struct attribute_group blk_trace_attr_group = { | |
1548 | .name = "trace", | |
1549 | .attrs = blk_trace_attrs, | |
1550 | }; | |
1551 | ||
09341997 LZ |
1552 | static const struct { |
1553 | int mask; | |
1554 | const char *str; | |
1555 | } mask_maps[] = { | |
1556 | { BLK_TC_READ, "read" }, | |
1557 | { BLK_TC_WRITE, "write" }, | |
c09c47ca | 1558 | { BLK_TC_FLUSH, "flush" }, |
09341997 LZ |
1559 | { BLK_TC_SYNC, "sync" }, |
1560 | { BLK_TC_QUEUE, "queue" }, | |
1561 | { BLK_TC_REQUEUE, "requeue" }, | |
1562 | { BLK_TC_ISSUE, "issue" }, | |
1563 | { BLK_TC_COMPLETE, "complete" }, | |
1564 | { BLK_TC_FS, "fs" }, | |
1565 | { BLK_TC_PC, "pc" }, | |
1566 | { BLK_TC_AHEAD, "ahead" }, | |
1567 | { BLK_TC_META, "meta" }, | |
1568 | { BLK_TC_DISCARD, "discard" }, | |
1569 | { BLK_TC_DRV_DATA, "drv_data" }, | |
c09c47ca | 1570 | { BLK_TC_FUA, "fua" }, |
09341997 LZ |
1571 | }; |
1572 | ||
1573 | static int blk_trace_str2mask(const char *str) | |
c71a8961 | 1574 | { |
09341997 | 1575 | int i; |
c71a8961 | 1576 | int mask = 0; |
9eb85125 | 1577 | char *buf, *s, *token; |
c71a8961 | 1578 | |
9eb85125 LZ |
1579 | buf = kstrdup(str, GFP_KERNEL); |
1580 | if (buf == NULL) | |
c71a8961 | 1581 | return -ENOMEM; |
9eb85125 | 1582 | s = strstrip(buf); |
c71a8961 ACM |
1583 | |
1584 | while (1) { | |
09341997 LZ |
1585 | token = strsep(&s, ","); |
1586 | if (token == NULL) | |
c71a8961 ACM |
1587 | break; |
1588 | ||
09341997 LZ |
1589 | if (*token == '\0') |
1590 | continue; | |
1591 | ||
1592 | for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { | |
1593 | if (strcasecmp(token, mask_maps[i].str) == 0) { | |
1594 | mask |= mask_maps[i].mask; | |
1595 | break; | |
1596 | } | |
1597 | } | |
1598 | if (i == ARRAY_SIZE(mask_maps)) { | |
1599 | mask = -EINVAL; | |
1600 | break; | |
1601 | } | |
c71a8961 | 1602 | } |
9eb85125 | 1603 | kfree(buf); |
c71a8961 ACM |
1604 | |
1605 | return mask; | |
1606 | } | |
1607 | ||
09341997 LZ |
1608 | static ssize_t blk_trace_mask2str(char *buf, int mask) |
1609 | { | |
1610 | int i; | |
1611 | char *p = buf; | |
1612 | ||
1613 | for (i = 0; i < ARRAY_SIZE(mask_maps); i++) { | |
1614 | if (mask & mask_maps[i].mask) { | |
1615 | p += sprintf(p, "%s%s", | |
1616 | (p == buf) ? "" : ",", mask_maps[i].str); | |
1617 | } | |
1618 | } | |
1619 | *p++ = '\n'; | |
1620 | ||
1621 | return p - buf; | |
1622 | } | |
1623 | ||
b125130b LZ |
1624 | static struct request_queue *blk_trace_get_queue(struct block_device *bdev) |
1625 | { | |
1626 | if (bdev->bd_disk == NULL) | |
1627 | return NULL; | |
1628 | ||
1629 | return bdev_get_queue(bdev); | |
1630 | } | |
1631 | ||
c71a8961 ACM |
1632 | static ssize_t sysfs_blk_trace_attr_show(struct device *dev, |
1633 | struct device_attribute *attr, | |
1634 | char *buf) | |
1635 | { | |
1636 | struct hd_struct *p = dev_to_part(dev); | |
1637 | struct request_queue *q; | |
1638 | struct block_device *bdev; | |
1639 | ssize_t ret = -ENXIO; | |
1640 | ||
c71a8961 ACM |
1641 | bdev = bdget(part_devt(p)); |
1642 | if (bdev == NULL) | |
01b284f9 | 1643 | goto out; |
c71a8961 | 1644 | |
b125130b | 1645 | q = blk_trace_get_queue(bdev); |
c71a8961 ACM |
1646 | if (q == NULL) |
1647 | goto out_bdput; | |
b125130b | 1648 | |
c71a8961 | 1649 | mutex_lock(&bdev->bd_mutex); |
cd649b8b LZ |
1650 | |
1651 | if (attr == &dev_attr_enable) { | |
1652 | ret = sprintf(buf, "%u\n", !!q->blk_trace); | |
1653 | goto out_unlock_bdev; | |
1654 | } | |
1655 | ||
c71a8961 ACM |
1656 | if (q->blk_trace == NULL) |
1657 | ret = sprintf(buf, "disabled\n"); | |
1658 | else if (attr == &dev_attr_act_mask) | |
09341997 | 1659 | ret = blk_trace_mask2str(buf, q->blk_trace->act_mask); |
c71a8961 ACM |
1660 | else if (attr == &dev_attr_pid) |
1661 | ret = sprintf(buf, "%u\n", q->blk_trace->pid); | |
1662 | else if (attr == &dev_attr_start_lba) | |
1663 | ret = sprintf(buf, "%llu\n", q->blk_trace->start_lba); | |
1664 | else if (attr == &dev_attr_end_lba) | |
1665 | ret = sprintf(buf, "%llu\n", q->blk_trace->end_lba); | |
cd649b8b LZ |
1666 | |
1667 | out_unlock_bdev: | |
c71a8961 ACM |
1668 | mutex_unlock(&bdev->bd_mutex); |
1669 | out_bdput: | |
1670 | bdput(bdev); | |
01b284f9 | 1671 | out: |
c71a8961 ACM |
1672 | return ret; |
1673 | } | |
1674 | ||
1675 | static ssize_t sysfs_blk_trace_attr_store(struct device *dev, | |
1676 | struct device_attribute *attr, | |
1677 | const char *buf, size_t count) | |
1678 | { | |
1679 | struct block_device *bdev; | |
1680 | struct request_queue *q; | |
1681 | struct hd_struct *p; | |
1682 | u64 value; | |
09341997 | 1683 | ssize_t ret = -EINVAL; |
c71a8961 ACM |
1684 | |
1685 | if (count == 0) | |
1686 | goto out; | |
1687 | ||
1688 | if (attr == &dev_attr_act_mask) { | |
1689 | if (sscanf(buf, "%llx", &value) != 1) { | |
1690 | /* Assume it is a list of trace category names */ | |
09341997 LZ |
1691 | ret = blk_trace_str2mask(buf); |
1692 | if (ret < 0) | |
c71a8961 | 1693 | goto out; |
09341997 | 1694 | value = ret; |
c71a8961 ACM |
1695 | } |
1696 | } else if (sscanf(buf, "%llu", &value) != 1) | |
1697 | goto out; | |
1698 | ||
09341997 LZ |
1699 | ret = -ENXIO; |
1700 | ||
c71a8961 ACM |
1701 | p = dev_to_part(dev); |
1702 | bdev = bdget(part_devt(p)); | |
1703 | if (bdev == NULL) | |
01b284f9 | 1704 | goto out; |
c71a8961 | 1705 | |
b125130b | 1706 | q = blk_trace_get_queue(bdev); |
c71a8961 ACM |
1707 | if (q == NULL) |
1708 | goto out_bdput; | |
1709 | ||
1710 | mutex_lock(&bdev->bd_mutex); | |
cd649b8b LZ |
1711 | |
1712 | if (attr == &dev_attr_enable) { | |
1713 | if (value) | |
9908c309 | 1714 | ret = blk_trace_setup_queue(q, bdev); |
cd649b8b LZ |
1715 | else |
1716 | ret = blk_trace_remove_queue(q); | |
1717 | goto out_unlock_bdev; | |
1718 | } | |
1719 | ||
c71a8961 ACM |
1720 | ret = 0; |
1721 | if (q->blk_trace == NULL) | |
9908c309 | 1722 | ret = blk_trace_setup_queue(q, bdev); |
c71a8961 ACM |
1723 | |
1724 | if (ret == 0) { | |
1725 | if (attr == &dev_attr_act_mask) | |
1726 | q->blk_trace->act_mask = value; | |
1727 | else if (attr == &dev_attr_pid) | |
1728 | q->blk_trace->pid = value; | |
1729 | else if (attr == &dev_attr_start_lba) | |
1730 | q->blk_trace->start_lba = value; | |
1731 | else if (attr == &dev_attr_end_lba) | |
1732 | q->blk_trace->end_lba = value; | |
c71a8961 | 1733 | } |
cd649b8b LZ |
1734 | |
1735 | out_unlock_bdev: | |
c71a8961 ACM |
1736 | mutex_unlock(&bdev->bd_mutex); |
1737 | out_bdput: | |
1738 | bdput(bdev); | |
c71a8961 | 1739 | out: |
cd649b8b | 1740 | return ret ? ret : count; |
c71a8961 | 1741 | } |
cd649b8b | 1742 | |
1d54ad6d LZ |
1743 | int blk_trace_init_sysfs(struct device *dev) |
1744 | { | |
1745 | return sysfs_create_group(&dev->kobj, &blk_trace_attr_group); | |
1746 | } | |
1747 | ||
48c0d4d4 ZK |
1748 | void blk_trace_remove_sysfs(struct device *dev) |
1749 | { | |
1750 | sysfs_remove_group(&dev->kobj, &blk_trace_attr_group); | |
1751 | } | |
1752 | ||
55782138 LZ |
1753 | #endif /* CONFIG_BLK_DEV_IO_TRACE */ |
1754 | ||
1755 | #ifdef CONFIG_EVENT_TRACING | |
1756 | ||
1757 | void blk_dump_cmd(char *buf, struct request *rq) | |
1758 | { | |
1759 | int i, end; | |
1760 | int len = rq->cmd_len; | |
1761 | unsigned char *cmd = rq->cmd; | |
1762 | ||
33659ebb | 1763 | if (rq->cmd_type != REQ_TYPE_BLOCK_PC) { |
55782138 LZ |
1764 | buf[0] = '\0'; |
1765 | return; | |
1766 | } | |
1767 | ||
1768 | for (end = len - 1; end >= 0; end--) | |
1769 | if (cmd[end]) | |
1770 | break; | |
1771 | end++; | |
1772 | ||
1773 | for (i = 0; i < len; i++) { | |
1774 | buf += sprintf(buf, "%s%02x", i == 0 ? "" : " ", cmd[i]); | |
1775 | if (i == end && end != len - 1) { | |
1776 | sprintf(buf, " .."); | |
1777 | break; | |
1778 | } | |
1779 | } | |
1780 | } | |
1781 | ||
1782 | void blk_fill_rwbs(char *rwbs, u32 rw, int bytes) | |
1783 | { | |
1784 | int i = 0; | |
1785 | ||
c09c47ca NK |
1786 | if (rw & REQ_FLUSH) |
1787 | rwbs[i++] = 'F'; | |
1788 | ||
55782138 LZ |
1789 | if (rw & WRITE) |
1790 | rwbs[i++] = 'W'; | |
7b6d91da | 1791 | else if (rw & REQ_DISCARD) |
55782138 LZ |
1792 | rwbs[i++] = 'D'; |
1793 | else if (bytes) | |
1794 | rwbs[i++] = 'R'; | |
1795 | else | |
1796 | rwbs[i++] = 'N'; | |
1797 | ||
c09c47ca NK |
1798 | if (rw & REQ_FUA) |
1799 | rwbs[i++] = 'F'; | |
7b6d91da | 1800 | if (rw & REQ_RAHEAD) |
55782138 | 1801 | rwbs[i++] = 'A'; |
7b6d91da | 1802 | if (rw & REQ_SYNC) |
55782138 | 1803 | rwbs[i++] = 'S'; |
7b6d91da | 1804 | if (rw & REQ_META) |
55782138 | 1805 | rwbs[i++] = 'M'; |
8d57a98c AH |
1806 | if (rw & REQ_SECURE) |
1807 | rwbs[i++] = 'E'; | |
55782138 LZ |
1808 | |
1809 | rwbs[i] = '\0'; | |
1810 | } | |
1811 | ||
55782138 LZ |
1812 | #endif /* CONFIG_EVENT_TRACING */ |
1813 |