diff options
Diffstat (limited to 'block')
-rw-r--r-- | block/Kconfig | 16 | ||||
-rw-r--r-- | block/Makefile | 1 | ||||
-rw-r--r-- | block/blktrace.c | 860 |
3 files changed, 0 insertions, 877 deletions
diff --git a/block/Kconfig b/block/Kconfig index 0cbb3b88b59a..e7d12782bcfb 100644 --- a/block/Kconfig +++ b/block/Kconfig | |||
@@ -44,22 +44,6 @@ config LBD | |||
44 | 44 | ||
45 | If unsure, say N. | 45 | If unsure, say N. |
46 | 46 | ||
47 | config BLK_DEV_IO_TRACE | ||
48 | bool "Support for tracing block io actions" | ||
49 | depends on SYSFS | ||
50 | select RELAY | ||
51 | select DEBUG_FS | ||
52 | select TRACEPOINTS | ||
53 | help | ||
54 | Say Y here if you want to be able to trace the block layer actions | ||
55 | on a given queue. Tracing allows you to see any traffic happening | ||
56 | on a block device queue. For more information (and the userspace | ||
57 | support tools needed), fetch the blktrace tools from: | ||
58 | |||
59 | git://git.kernel.dk/blktrace.git | ||
60 | |||
61 | If unsure, say N. | ||
62 | |||
63 | config BLK_DEV_BSG | 47 | config BLK_DEV_BSG |
64 | bool "Block layer SG support v4 (EXPERIMENTAL)" | 48 | bool "Block layer SG support v4 (EXPERIMENTAL)" |
65 | depends on EXPERIMENTAL | 49 | depends on EXPERIMENTAL |
diff --git a/block/Makefile b/block/Makefile index bfe73049f939..e9fa4dd690f2 100644 --- a/block/Makefile +++ b/block/Makefile | |||
@@ -13,6 +13,5 @@ obj-$(CONFIG_IOSCHED_AS) += as-iosched.o | |||
13 | obj-$(CONFIG_IOSCHED_DEADLINE) += deadline-iosched.o | 13 | obj-$(CONFIG_IOSCHED_DEADLINE) += deadline-iosched.o |
14 | obj-$(CONFIG_IOSCHED_CFQ) += cfq-iosched.o | 14 | obj-$(CONFIG_IOSCHED_CFQ) += cfq-iosched.o |
15 | 15 | ||
16 | obj-$(CONFIG_BLK_DEV_IO_TRACE) += blktrace.o | ||
17 | obj-$(CONFIG_BLOCK_COMPAT) += compat_ioctl.o | 16 | obj-$(CONFIG_BLOCK_COMPAT) += compat_ioctl.o |
18 | obj-$(CONFIG_BLK_DEV_INTEGRITY) += blk-integrity.o | 17 | obj-$(CONFIG_BLK_DEV_INTEGRITY) += blk-integrity.o |
diff --git a/block/blktrace.c b/block/blktrace.c deleted file mode 100644 index 7cf9d1ff45a0..000000000000 --- a/block/blktrace.c +++ /dev/null | |||
@@ -1,860 +0,0 @@ | |||
1 | /* | ||
2 | * Copyright (C) 2006 Jens Axboe <axboe@kernel.dk> | ||
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 | */ | ||
18 | #include <linux/kernel.h> | ||
19 | #include <linux/blkdev.h> | ||
20 | #include <linux/blktrace_api.h> | ||
21 | #include <linux/percpu.h> | ||
22 | #include <linux/init.h> | ||
23 | #include <linux/mutex.h> | ||
24 | #include <linux/debugfs.h> | ||
25 | #include <linux/time.h> | ||
26 | #include <trace/block.h> | ||
27 | #include <asm/uaccess.h> | ||
28 | |||
29 | static unsigned int blktrace_seq __read_mostly = 1; | ||
30 | |||
31 | /* Global reference count of probes */ | ||
32 | static DEFINE_MUTEX(blk_probe_mutex); | ||
33 | static atomic_t blk_probes_ref = ATOMIC_INIT(0); | ||
34 | |||
35 | static int blk_register_tracepoints(void); | ||
36 | static void blk_unregister_tracepoints(void); | ||
37 | |||
38 | /* | ||
39 | * Send out a notify message. | ||
40 | */ | ||
41 | static void trace_note(struct blk_trace *bt, pid_t pid, int action, | ||
42 | const void *data, size_t len) | ||
43 | { | ||
44 | struct blk_io_trace *t; | ||
45 | |||
46 | t = relay_reserve(bt->rchan, sizeof(*t) + len); | ||
47 | if (t) { | ||
48 | const int cpu = smp_processor_id(); | ||
49 | |||
50 | t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; | ||
51 | t->time = ktime_to_ns(ktime_get()); | ||
52 | t->device = bt->dev; | ||
53 | t->action = action; | ||
54 | t->pid = pid; | ||
55 | t->cpu = cpu; | ||
56 | t->pdu_len = len; | ||
57 | memcpy((void *) t + sizeof(*t), data, len); | ||
58 | } | ||
59 | } | ||
60 | |||
61 | /* | ||
62 | * Send out a notify for this process, if we haven't done so since a trace | ||
63 | * started | ||
64 | */ | ||
65 | static void trace_note_tsk(struct blk_trace *bt, struct task_struct *tsk) | ||
66 | { | ||
67 | tsk->btrace_seq = blktrace_seq; | ||
68 | trace_note(bt, tsk->pid, BLK_TN_PROCESS, tsk->comm, sizeof(tsk->comm)); | ||
69 | } | ||
70 | |||
71 | static void trace_note_time(struct blk_trace *bt) | ||
72 | { | ||
73 | struct timespec now; | ||
74 | unsigned long flags; | ||
75 | u32 words[2]; | ||
76 | |||
77 | getnstimeofday(&now); | ||
78 | words[0] = now.tv_sec; | ||
79 | words[1] = now.tv_nsec; | ||
80 | |||
81 | local_irq_save(flags); | ||
82 | trace_note(bt, 0, BLK_TN_TIMESTAMP, words, sizeof(words)); | ||
83 | local_irq_restore(flags); | ||
84 | } | ||
85 | |||
86 | void __trace_note_message(struct blk_trace *bt, const char *fmt, ...) | ||
87 | { | ||
88 | int n; | ||
89 | va_list args; | ||
90 | unsigned long flags; | ||
91 | char *buf; | ||
92 | |||
93 | local_irq_save(flags); | ||
94 | buf = per_cpu_ptr(bt->msg_data, smp_processor_id()); | ||
95 | va_start(args, fmt); | ||
96 | n = vscnprintf(buf, BLK_TN_MAX_MSG, fmt, args); | ||
97 | va_end(args); | ||
98 | |||
99 | trace_note(bt, 0, BLK_TN_MESSAGE, buf, n); | ||
100 | local_irq_restore(flags); | ||
101 | } | ||
102 | EXPORT_SYMBOL_GPL(__trace_note_message); | ||
103 | |||
104 | static int act_log_check(struct blk_trace *bt, u32 what, sector_t sector, | ||
105 | pid_t pid) | ||
106 | { | ||
107 | if (((bt->act_mask << BLK_TC_SHIFT) & what) == 0) | ||
108 | return 1; | ||
109 | if (sector < bt->start_lba || sector > bt->end_lba) | ||
110 | return 1; | ||
111 | if (bt->pid && pid != bt->pid) | ||
112 | return 1; | ||
113 | |||
114 | return 0; | ||
115 | } | ||
116 | |||
117 | /* | ||
118 | * Data direction bit lookup | ||
119 | */ | ||
120 | static u32 ddir_act[2] __read_mostly = { BLK_TC_ACT(BLK_TC_READ), BLK_TC_ACT(BLK_TC_WRITE) }; | ||
121 | |||
122 | /* The ilog2() calls fall out because they're constant */ | ||
123 | #define MASK_TC_BIT(rw, __name) ( (rw & (1 << BIO_RW_ ## __name)) << \ | ||
124 | (ilog2(BLK_TC_ ## __name) + BLK_TC_SHIFT - BIO_RW_ ## __name) ) | ||
125 | |||
126 | /* | ||
127 | * The worker for the various blk_add_trace*() types. Fills out a | ||
128 | * blk_io_trace structure and places it in a per-cpu subbuffer. | ||
129 | */ | ||
130 | static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, | ||
131 | int rw, u32 what, int error, int pdu_len, void *pdu_data) | ||
132 | { | ||
133 | struct task_struct *tsk = current; | ||
134 | struct blk_io_trace *t; | ||
135 | unsigned long flags; | ||
136 | unsigned long *sequence; | ||
137 | pid_t pid; | ||
138 | int cpu; | ||
139 | |||
140 | if (unlikely(bt->trace_state != Blktrace_running)) | ||
141 | return; | ||
142 | |||
143 | what |= ddir_act[rw & WRITE]; | ||
144 | what |= MASK_TC_BIT(rw, BARRIER); | ||
145 | what |= MASK_TC_BIT(rw, SYNCIO); | ||
146 | what |= MASK_TC_BIT(rw, AHEAD); | ||
147 | what |= MASK_TC_BIT(rw, META); | ||
148 | what |= MASK_TC_BIT(rw, DISCARD); | ||
149 | |||
150 | pid = tsk->pid; | ||
151 | if (unlikely(act_log_check(bt, what, sector, pid))) | ||
152 | return; | ||
153 | |||
154 | /* | ||
155 | * A word about the locking here - we disable interrupts to reserve | ||
156 | * some space in the relay per-cpu buffer, to prevent an irq | ||
157 | * from coming in and stepping on our toes. | ||
158 | */ | ||
159 | local_irq_save(flags); | ||
160 | |||
161 | if (unlikely(tsk->btrace_seq != blktrace_seq)) | ||
162 | trace_note_tsk(bt, tsk); | ||
163 | |||
164 | t = relay_reserve(bt->rchan, sizeof(*t) + pdu_len); | ||
165 | if (t) { | ||
166 | cpu = smp_processor_id(); | ||
167 | sequence = per_cpu_ptr(bt->sequence, cpu); | ||
168 | |||
169 | t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; | ||
170 | t->sequence = ++(*sequence); | ||
171 | t->time = ktime_to_ns(ktime_get()); | ||
172 | t->sector = sector; | ||
173 | t->bytes = bytes; | ||
174 | t->action = what; | ||
175 | t->pid = pid; | ||
176 | t->device = bt->dev; | ||
177 | t->cpu = cpu; | ||
178 | t->error = error; | ||
179 | t->pdu_len = pdu_len; | ||
180 | |||
181 | if (pdu_len) | ||
182 | memcpy((void *) t + sizeof(*t), pdu_data, pdu_len); | ||
183 | } | ||
184 | |||
185 | local_irq_restore(flags); | ||
186 | } | ||
187 | |||
188 | static struct dentry *blk_tree_root; | ||
189 | static DEFINE_MUTEX(blk_tree_mutex); | ||
190 | |||
191 | static void blk_trace_cleanup(struct blk_trace *bt) | ||
192 | { | ||
193 | debugfs_remove(bt->msg_file); | ||
194 | debugfs_remove(bt->dropped_file); | ||
195 | relay_close(bt->rchan); | ||
196 | free_percpu(bt->sequence); | ||
197 | free_percpu(bt->msg_data); | ||
198 | kfree(bt); | ||
199 | mutex_lock(&blk_probe_mutex); | ||
200 | if (atomic_dec_and_test(&blk_probes_ref)) | ||
201 | blk_unregister_tracepoints(); | ||
202 | mutex_unlock(&blk_probe_mutex); | ||
203 | } | ||
204 | |||
205 | int blk_trace_remove(struct request_queue *q) | ||
206 | { | ||
207 | struct blk_trace *bt; | ||
208 | |||
209 | bt = xchg(&q->blk_trace, NULL); | ||
210 | if (!bt) | ||
211 | return -EINVAL; | ||
212 | |||
213 | if (bt->trace_state == Blktrace_setup || | ||
214 | bt->trace_state == Blktrace_stopped) | ||
215 | blk_trace_cleanup(bt); | ||
216 | |||
217 | return 0; | ||
218 | } | ||
219 | EXPORT_SYMBOL_GPL(blk_trace_remove); | ||
220 | |||
221 | static int blk_dropped_open(struct inode *inode, struct file *filp) | ||
222 | { | ||
223 | filp->private_data = inode->i_private; | ||
224 | |||
225 | return 0; | ||
226 | } | ||
227 | |||
228 | static ssize_t blk_dropped_read(struct file *filp, char __user *buffer, | ||
229 | size_t count, loff_t *ppos) | ||
230 | { | ||
231 | struct blk_trace *bt = filp->private_data; | ||
232 | char buf[16]; | ||
233 | |||
234 | snprintf(buf, sizeof(buf), "%u\n", atomic_read(&bt->dropped)); | ||
235 | |||
236 | return simple_read_from_buffer(buffer, count, ppos, buf, strlen(buf)); | ||
237 | } | ||
238 | |||
239 | static const struct file_operations blk_dropped_fops = { | ||
240 | .owner = THIS_MODULE, | ||
241 | .open = blk_dropped_open, | ||
242 | .read = blk_dropped_read, | ||
243 | }; | ||
244 | |||
245 | static int blk_msg_open(struct inode *inode, struct file *filp) | ||
246 | { | ||
247 | filp->private_data = inode->i_private; | ||
248 | |||
249 | return 0; | ||
250 | } | ||
251 | |||
252 | static ssize_t blk_msg_write(struct file *filp, const char __user *buffer, | ||
253 | size_t count, loff_t *ppos) | ||
254 | { | ||
255 | char *msg; | ||
256 | struct blk_trace *bt; | ||
257 | |||
258 | if (count > BLK_TN_MAX_MSG) | ||
259 | return -EINVAL; | ||
260 | |||
261 | msg = kmalloc(count, GFP_KERNEL); | ||
262 | if (msg == NULL) | ||
263 | return -ENOMEM; | ||
264 | |||
265 | if (copy_from_user(msg, buffer, count)) { | ||
266 | kfree(msg); | ||
267 | return -EFAULT; | ||
268 | } | ||
269 | |||
270 | bt = filp->private_data; | ||
271 | __trace_note_message(bt, "%s", msg); | ||
272 | kfree(msg); | ||
273 | |||
274 | return count; | ||
275 | } | ||
276 | |||
277 | static const struct file_operations blk_msg_fops = { | ||
278 | .owner = THIS_MODULE, | ||
279 | .open = blk_msg_open, | ||
280 | .write = blk_msg_write, | ||
281 | }; | ||
282 | |||
283 | /* | ||
284 | * Keep track of how many times we encountered a full subbuffer, to aid | ||
285 | * the user space app in telling how many lost events there were. | ||
286 | */ | ||
287 | static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf, | ||
288 | void *prev_subbuf, size_t prev_padding) | ||
289 | { | ||
290 | struct blk_trace *bt; | ||
291 | |||
292 | if (!relay_buf_full(buf)) | ||
293 | return 1; | ||
294 | |||
295 | bt = buf->chan->private_data; | ||
296 | atomic_inc(&bt->dropped); | ||
297 | return 0; | ||
298 | } | ||
299 | |||
300 | static int blk_remove_buf_file_callback(struct dentry *dentry) | ||
301 | { | ||
302 | struct dentry *parent = dentry->d_parent; | ||
303 | debugfs_remove(dentry); | ||
304 | |||
305 | /* | ||
306 | * this will fail for all but the last file, but that is ok. what we | ||
307 | * care about is the top level buts->name directory going away, when | ||
308 | * the last trace file is gone. Then we don't have to rmdir() that | ||
309 | * manually on trace stop, so it nicely solves the issue with | ||
310 | * force killing of running traces. | ||
311 | */ | ||
312 | |||
313 | debugfs_remove(parent); | ||
314 | return 0; | ||
315 | } | ||
316 | |||
317 | static struct dentry *blk_create_buf_file_callback(const char *filename, | ||
318 | struct dentry *parent, | ||
319 | int mode, | ||
320 | struct rchan_buf *buf, | ||
321 | int *is_global) | ||
322 | { | ||
323 | return debugfs_create_file(filename, mode, parent, buf, | ||
324 | &relay_file_operations); | ||
325 | } | ||
326 | |||
327 | static struct rchan_callbacks blk_relay_callbacks = { | ||
328 | .subbuf_start = blk_subbuf_start_callback, | ||
329 | .create_buf_file = blk_create_buf_file_callback, | ||
330 | .remove_buf_file = blk_remove_buf_file_callback, | ||
331 | }; | ||
332 | |||
333 | /* | ||
334 | * Setup everything required to start tracing | ||
335 | */ | ||
336 | int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, | ||
337 | struct blk_user_trace_setup *buts) | ||
338 | { | ||
339 | struct blk_trace *old_bt, *bt = NULL; | ||
340 | struct dentry *dir = NULL; | ||
341 | int ret, i; | ||
342 | |||
343 | if (!buts->buf_size || !buts->buf_nr) | ||
344 | return -EINVAL; | ||
345 | |||
346 | strncpy(buts->name, name, BLKTRACE_BDEV_SIZE); | ||
347 | buts->name[BLKTRACE_BDEV_SIZE - 1] = '\0'; | ||
348 | |||
349 | /* | ||
350 | * some device names have larger paths - convert the slashes | ||
351 | * to underscores for this to work as expected | ||
352 | */ | ||
353 | for (i = 0; i < strlen(buts->name); i++) | ||
354 | if (buts->name[i] == '/') | ||
355 | buts->name[i] = '_'; | ||
356 | |||
357 | ret = -ENOMEM; | ||
358 | bt = kzalloc(sizeof(*bt), GFP_KERNEL); | ||
359 | if (!bt) | ||
360 | goto err; | ||
361 | |||
362 | bt->sequence = alloc_percpu(unsigned long); | ||
363 | if (!bt->sequence) | ||
364 | goto err; | ||
365 | |||
366 | bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG); | ||
367 | if (!bt->msg_data) | ||
368 | goto err; | ||
369 | |||
370 | ret = -ENOENT; | ||
371 | |||
372 | if (!blk_tree_root) { | ||
373 | blk_tree_root = debugfs_create_dir("block", NULL); | ||
374 | if (!blk_tree_root) | ||
375 | return -ENOMEM; | ||
376 | } | ||
377 | |||
378 | dir = debugfs_create_dir(buts->name, blk_tree_root); | ||
379 | |||
380 | if (!dir) | ||
381 | goto err; | ||
382 | |||
383 | bt->dir = dir; | ||
384 | bt->dev = dev; | ||
385 | atomic_set(&bt->dropped, 0); | ||
386 | |||
387 | ret = -EIO; | ||
388 | bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt, &blk_dropped_fops); | ||
389 | if (!bt->dropped_file) | ||
390 | goto err; | ||
391 | |||
392 | bt->msg_file = debugfs_create_file("msg", 0222, dir, bt, &blk_msg_fops); | ||
393 | if (!bt->msg_file) | ||
394 | goto err; | ||
395 | |||
396 | bt->rchan = relay_open("trace", dir, buts->buf_size, | ||
397 | buts->buf_nr, &blk_relay_callbacks, bt); | ||
398 | if (!bt->rchan) | ||
399 | goto err; | ||
400 | |||
401 | bt->act_mask = buts->act_mask; | ||
402 | if (!bt->act_mask) | ||
403 | bt->act_mask = (u16) -1; | ||
404 | |||
405 | bt->start_lba = buts->start_lba; | ||
406 | bt->end_lba = buts->end_lba; | ||
407 | if (!bt->end_lba) | ||
408 | bt->end_lba = -1ULL; | ||
409 | |||
410 | bt->pid = buts->pid; | ||
411 | bt->trace_state = Blktrace_setup; | ||
412 | |||
413 | mutex_lock(&blk_probe_mutex); | ||
414 | if (atomic_add_return(1, &blk_probes_ref) == 1) { | ||
415 | ret = blk_register_tracepoints(); | ||
416 | if (ret) | ||
417 | goto probe_err; | ||
418 | } | ||
419 | mutex_unlock(&blk_probe_mutex); | ||
420 | |||
421 | ret = -EBUSY; | ||
422 | old_bt = xchg(&q->blk_trace, bt); | ||
423 | if (old_bt) { | ||
424 | (void) xchg(&q->blk_trace, old_bt); | ||
425 | goto err; | ||
426 | } | ||
427 | |||
428 | return 0; | ||
429 | probe_err: | ||
430 | atomic_dec(&blk_probes_ref); | ||
431 | mutex_unlock(&blk_probe_mutex); | ||
432 | err: | ||
433 | if (bt) { | ||
434 | if (bt->msg_file) | ||
435 | debugfs_remove(bt->msg_file); | ||
436 | if (bt->dropped_file) | ||
437 | debugfs_remove(bt->dropped_file); | ||
438 | free_percpu(bt->sequence); | ||
439 | free_percpu(bt->msg_data); | ||
440 | if (bt->rchan) | ||
441 | relay_close(bt->rchan); | ||
442 | kfree(bt); | ||
443 | } | ||
444 | return ret; | ||
445 | } | ||
446 | |||
447 | int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, | ||
448 | char __user *arg) | ||
449 | { | ||
450 | struct blk_user_trace_setup buts; | ||
451 | int ret; | ||
452 | |||
453 | ret = copy_from_user(&buts, arg, sizeof(buts)); | ||
454 | if (ret) | ||
455 | return -EFAULT; | ||
456 | |||
457 | ret = do_blk_trace_setup(q, name, dev, &buts); | ||
458 | if (ret) | ||
459 | return ret; | ||
460 | |||
461 | if (copy_to_user(arg, &buts, sizeof(buts))) | ||
462 | return -EFAULT; | ||
463 | |||
464 | return 0; | ||
465 | } | ||
466 | EXPORT_SYMBOL_GPL(blk_trace_setup); | ||
467 | |||
468 | int blk_trace_startstop(struct request_queue *q, int start) | ||
469 | { | ||
470 | struct blk_trace *bt; | ||
471 | int ret; | ||
472 | |||
473 | if ((bt = q->blk_trace) == NULL) | ||
474 | return -EINVAL; | ||
475 | |||
476 | /* | ||
477 | * For starting a trace, we can transition from a setup or stopped | ||
478 | * trace. For stopping a trace, the state must be running | ||
479 | */ | ||
480 | ret = -EINVAL; | ||
481 | if (start) { | ||
482 | if (bt->trace_state == Blktrace_setup || | ||
483 | bt->trace_state == Blktrace_stopped) { | ||
484 | blktrace_seq++; | ||
485 | smp_mb(); | ||
486 | bt->trace_state = Blktrace_running; | ||
487 | |||
488 | trace_note_time(bt); | ||
489 | ret = 0; | ||
490 | } | ||
491 | } else { | ||
492 | if (bt->trace_state == Blktrace_running) { | ||
493 | bt->trace_state = Blktrace_stopped; | ||
494 | relay_flush(bt->rchan); | ||
495 | ret = 0; | ||
496 | } | ||
497 | } | ||
498 | |||
499 | return ret; | ||
500 | } | ||
501 | EXPORT_SYMBOL_GPL(blk_trace_startstop); | ||
502 | |||
503 | /** | ||
504 | * blk_trace_ioctl: - handle the ioctls associated with tracing | ||
505 | * @bdev: the block device | ||
506 | * @cmd: the ioctl cmd | ||
507 | * @arg: the argument data, if any | ||
508 | * | ||
509 | **/ | ||
510 | int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) | ||
511 | { | ||
512 | struct request_queue *q; | ||
513 | int ret, start = 0; | ||
514 | char b[BDEVNAME_SIZE]; | ||
515 | |||
516 | q = bdev_get_queue(bdev); | ||
517 | if (!q) | ||
518 | return -ENXIO; | ||
519 | |||
520 | mutex_lock(&bdev->bd_mutex); | ||
521 | |||
522 | switch (cmd) { | ||
523 | case BLKTRACESETUP: | ||
524 | bdevname(bdev, b); | ||
525 | ret = blk_trace_setup(q, b, bdev->bd_dev, arg); | ||
526 | break; | ||
527 | case BLKTRACESTART: | ||
528 | start = 1; | ||
529 | case BLKTRACESTOP: | ||
530 | ret = blk_trace_startstop(q, start); | ||
531 | break; | ||
532 | case BLKTRACETEARDOWN: | ||
533 | ret = blk_trace_remove(q); | ||
534 | break; | ||
535 | default: | ||
536 | ret = -ENOTTY; | ||
537 | break; | ||
538 | } | ||
539 | |||
540 | mutex_unlock(&bdev->bd_mutex); | ||
541 | return ret; | ||
542 | } | ||
543 | |||
544 | /** | ||
545 | * blk_trace_shutdown: - stop and cleanup trace structures | ||
546 | * @q: the request queue associated with the device | ||
547 | * | ||
548 | **/ | ||
549 | void blk_trace_shutdown(struct request_queue *q) | ||
550 | { | ||
551 | if (q->blk_trace) { | ||
552 | blk_trace_startstop(q, 0); | ||
553 | blk_trace_remove(q); | ||
554 | } | ||
555 | } | ||
556 | |||
557 | /* | ||
558 | * blktrace probes | ||
559 | */ | ||
560 | |||
561 | /** | ||
562 | * blk_add_trace_rq - Add a trace for a request oriented action | ||
563 | * @q: queue the io is for | ||
564 | * @rq: the source request | ||
565 | * @what: the action | ||
566 | * | ||
567 | * Description: | ||
568 | * Records an action against a request. Will log the bio offset + size. | ||
569 | * | ||
570 | **/ | ||
571 | static void blk_add_trace_rq(struct request_queue *q, struct request *rq, | ||
572 | u32 what) | ||
573 | { | ||
574 | struct blk_trace *bt = q->blk_trace; | ||
575 | int rw = rq->cmd_flags & 0x03; | ||
576 | |||
577 | if (likely(!bt)) | ||
578 | return; | ||
579 | |||
580 | if (blk_discard_rq(rq)) | ||
581 | rw |= (1 << BIO_RW_DISCARD); | ||
582 | |||
583 | if (blk_pc_request(rq)) { | ||
584 | what |= BLK_TC_ACT(BLK_TC_PC); | ||
585 | __blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors, | ||
586 | sizeof(rq->cmd), rq->cmd); | ||
587 | } else { | ||
588 | what |= BLK_TC_ACT(BLK_TC_FS); | ||
589 | __blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, | ||
590 | rw, what, rq->errors, 0, NULL); | ||
591 | } | ||
592 | } | ||
593 | |||
594 | static void blk_add_trace_rq_abort(struct request_queue *q, struct request *rq) | ||
595 | { | ||
596 | blk_add_trace_rq(q, rq, BLK_TA_ABORT); | ||
597 | } | ||
598 | |||
599 | static void blk_add_trace_rq_insert(struct request_queue *q, struct request *rq) | ||
600 | { | ||
601 | blk_add_trace_rq(q, rq, BLK_TA_INSERT); | ||
602 | } | ||
603 | |||
604 | static void blk_add_trace_rq_issue(struct request_queue *q, struct request *rq) | ||
605 | { | ||
606 | blk_add_trace_rq(q, rq, BLK_TA_ISSUE); | ||
607 | } | ||
608 | |||
609 | static void blk_add_trace_rq_requeue(struct request_queue *q, struct request *rq) | ||
610 | { | ||
611 | blk_add_trace_rq(q, rq, BLK_TA_REQUEUE); | ||
612 | } | ||
613 | |||
614 | static void blk_add_trace_rq_complete(struct request_queue *q, struct request *rq) | ||
615 | { | ||
616 | blk_add_trace_rq(q, rq, BLK_TA_COMPLETE); | ||
617 | } | ||
618 | |||
619 | /** | ||
620 | * blk_add_trace_bio - Add a trace for a bio oriented action | ||
621 | * @q: queue the io is for | ||
622 | * @bio: the source bio | ||
623 | * @what: the action | ||
624 | * | ||
625 | * Description: | ||
626 | * Records an action against a bio. Will log the bio offset + size. | ||
627 | * | ||
628 | **/ | ||
629 | static void blk_add_trace_bio(struct request_queue *q, struct bio *bio, | ||
630 | u32 what) | ||
631 | { | ||
632 | struct blk_trace *bt = q->blk_trace; | ||
633 | |||
634 | if (likely(!bt)) | ||
635 | return; | ||
636 | |||
637 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, | ||
638 | !bio_flagged(bio, BIO_UPTODATE), 0, NULL); | ||
639 | } | ||
640 | |||
641 | static void blk_add_trace_bio_bounce(struct request_queue *q, struct bio *bio) | ||
642 | { | ||
643 | blk_add_trace_bio(q, bio, BLK_TA_BOUNCE); | ||
644 | } | ||
645 | |||
646 | static void blk_add_trace_bio_complete(struct request_queue *q, struct bio *bio) | ||
647 | { | ||
648 | blk_add_trace_bio(q, bio, BLK_TA_COMPLETE); | ||
649 | } | ||
650 | |||
651 | static void blk_add_trace_bio_backmerge(struct request_queue *q, struct bio *bio) | ||
652 | { | ||
653 | blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE); | ||
654 | } | ||
655 | |||
656 | static void blk_add_trace_bio_frontmerge(struct request_queue *q, struct bio *bio) | ||
657 | { | ||
658 | blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE); | ||
659 | } | ||
660 | |||
661 | static void blk_add_trace_bio_queue(struct request_queue *q, struct bio *bio) | ||
662 | { | ||
663 | blk_add_trace_bio(q, bio, BLK_TA_QUEUE); | ||
664 | } | ||
665 | |||
666 | static void blk_add_trace_getrq(struct request_queue *q, struct bio *bio, int rw) | ||
667 | { | ||
668 | if (bio) | ||
669 | blk_add_trace_bio(q, bio, BLK_TA_GETRQ); | ||
670 | else { | ||
671 | struct blk_trace *bt = q->blk_trace; | ||
672 | |||
673 | if (bt) | ||
674 | __blk_add_trace(bt, 0, 0, rw, BLK_TA_GETRQ, 0, 0, NULL); | ||
675 | } | ||
676 | } | ||
677 | |||
678 | |||
679 | static void blk_add_trace_sleeprq(struct request_queue *q, struct bio *bio, int rw) | ||
680 | { | ||
681 | if (bio) | ||
682 | blk_add_trace_bio(q, bio, BLK_TA_SLEEPRQ); | ||
683 | else { | ||
684 | struct blk_trace *bt = q->blk_trace; | ||
685 | |||
686 | if (bt) | ||
687 | __blk_add_trace(bt, 0, 0, rw, BLK_TA_SLEEPRQ, 0, 0, NULL); | ||
688 | } | ||
689 | } | ||
690 | |||
691 | static void blk_add_trace_plug(struct request_queue *q) | ||
692 | { | ||
693 | struct blk_trace *bt = q->blk_trace; | ||
694 | |||
695 | if (bt) | ||
696 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_PLUG, 0, 0, NULL); | ||
697 | } | ||
698 | |||
699 | static void blk_add_trace_unplug_io(struct request_queue *q) | ||
700 | { | ||
701 | struct blk_trace *bt = q->blk_trace; | ||
702 | |||
703 | if (bt) { | ||
704 | unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; | ||
705 | __be64 rpdu = cpu_to_be64(pdu); | ||
706 | |||
707 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_IO, 0, | ||
708 | sizeof(rpdu), &rpdu); | ||
709 | } | ||
710 | } | ||
711 | |||
712 | static void blk_add_trace_unplug_timer(struct request_queue *q) | ||
713 | { | ||
714 | struct blk_trace *bt = q->blk_trace; | ||
715 | |||
716 | if (bt) { | ||
717 | unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; | ||
718 | __be64 rpdu = cpu_to_be64(pdu); | ||
719 | |||
720 | __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_TIMER, 0, | ||
721 | sizeof(rpdu), &rpdu); | ||
722 | } | ||
723 | } | ||
724 | |||
725 | static void blk_add_trace_split(struct request_queue *q, struct bio *bio, | ||
726 | unsigned int pdu) | ||
727 | { | ||
728 | struct blk_trace *bt = q->blk_trace; | ||
729 | |||
730 | if (bt) { | ||
731 | __be64 rpdu = cpu_to_be64(pdu); | ||
732 | |||
733 | __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, | ||
734 | BLK_TA_SPLIT, !bio_flagged(bio, BIO_UPTODATE), | ||
735 | sizeof(rpdu), &rpdu); | ||
736 | } | ||
737 | } | ||
738 | |||
739 | /** | ||
740 | * blk_add_trace_remap - Add a trace for a remap operation | ||
741 | * @q: queue the io is for | ||
742 | * @bio: the source bio | ||
743 | * @dev: target device | ||
744 | * @from: source sector | ||
745 | * @to: target sector | ||
746 | * | ||
747 | * Description: | ||
748 | * Device mapper or raid target sometimes need to split a bio because | ||
749 | * it spans a stripe (or similar). Add a trace for that action. | ||
750 | * | ||
751 | **/ | ||
752 | static void blk_add_trace_remap(struct request_queue *q, struct bio *bio, | ||
753 | dev_t dev, sector_t from, sector_t to) | ||
754 | { | ||
755 | struct blk_trace *bt = q->blk_trace; | ||
756 | struct blk_io_trace_remap r; | ||
757 | |||
758 | if (likely(!bt)) | ||
759 | return; | ||
760 | |||
761 | r.device = cpu_to_be32(dev); | ||
762 | r.device_from = cpu_to_be32(bio->bi_bdev->bd_dev); | ||
763 | r.sector = cpu_to_be64(to); | ||
764 | |||
765 | __blk_add_trace(bt, from, bio->bi_size, bio->bi_rw, BLK_TA_REMAP, | ||
766 | !bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r); | ||
767 | } | ||
768 | |||
769 | /** | ||
770 | * blk_add_driver_data - Add binary message with driver-specific data | ||
771 | * @q: queue the io is for | ||
772 | * @rq: io request | ||
773 | * @data: driver-specific data | ||
774 | * @len: length of driver-specific data | ||
775 | * | ||
776 | * Description: | ||
777 | * Some drivers might want to write driver-specific data per request. | ||
778 | * | ||
779 | **/ | ||
780 | void blk_add_driver_data(struct request_queue *q, | ||
781 | struct request *rq, | ||
782 | void *data, size_t len) | ||
783 | { | ||
784 | struct blk_trace *bt = q->blk_trace; | ||
785 | |||
786 | if (likely(!bt)) | ||
787 | return; | ||
788 | |||
789 | if (blk_pc_request(rq)) | ||
790 | __blk_add_trace(bt, 0, rq->data_len, 0, BLK_TA_DRV_DATA, | ||
791 | rq->errors, len, data); | ||
792 | else | ||
793 | __blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, | ||
794 | 0, BLK_TA_DRV_DATA, rq->errors, len, data); | ||
795 | } | ||
796 | EXPORT_SYMBOL_GPL(blk_add_driver_data); | ||
797 | |||
798 | static int blk_register_tracepoints(void) | ||
799 | { | ||
800 | int ret; | ||
801 | |||
802 | ret = register_trace_block_rq_abort(blk_add_trace_rq_abort); | ||
803 | WARN_ON(ret); | ||
804 | ret = register_trace_block_rq_insert(blk_add_trace_rq_insert); | ||
805 | WARN_ON(ret); | ||
806 | ret = register_trace_block_rq_issue(blk_add_trace_rq_issue); | ||
807 | WARN_ON(ret); | ||
808 | ret = register_trace_block_rq_requeue(blk_add_trace_rq_requeue); | ||
809 | WARN_ON(ret); | ||
810 | ret = register_trace_block_rq_complete(blk_add_trace_rq_complete); | ||
811 | WARN_ON(ret); | ||
812 | ret = register_trace_block_bio_bounce(blk_add_trace_bio_bounce); | ||
813 | WARN_ON(ret); | ||
814 | ret = register_trace_block_bio_complete(blk_add_trace_bio_complete); | ||
815 | WARN_ON(ret); | ||
816 | ret = register_trace_block_bio_backmerge(blk_add_trace_bio_backmerge); | ||
817 | WARN_ON(ret); | ||
818 | ret = register_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge); | ||
819 | WARN_ON(ret); | ||
820 | ret = register_trace_block_bio_queue(blk_add_trace_bio_queue); | ||
821 | WARN_ON(ret); | ||
822 | ret = register_trace_block_getrq(blk_add_trace_getrq); | ||
823 | WARN_ON(ret); | ||
824 | ret = register_trace_block_sleeprq(blk_add_trace_sleeprq); | ||
825 | WARN_ON(ret); | ||
826 | ret = register_trace_block_plug(blk_add_trace_plug); | ||
827 | WARN_ON(ret); | ||
828 | ret = register_trace_block_unplug_timer(blk_add_trace_unplug_timer); | ||
829 | WARN_ON(ret); | ||
830 | ret = register_trace_block_unplug_io(blk_add_trace_unplug_io); | ||
831 | WARN_ON(ret); | ||
832 | ret = register_trace_block_split(blk_add_trace_split); | ||
833 | WARN_ON(ret); | ||
834 | ret = register_trace_block_remap(blk_add_trace_remap); | ||
835 | WARN_ON(ret); | ||
836 | return 0; | ||
837 | } | ||
838 | |||
839 | static void blk_unregister_tracepoints(void) | ||
840 | { | ||
841 | unregister_trace_block_remap(blk_add_trace_remap); | ||
842 | unregister_trace_block_split(blk_add_trace_split); | ||
843 | unregister_trace_block_unplug_io(blk_add_trace_unplug_io); | ||
844 | unregister_trace_block_unplug_timer(blk_add_trace_unplug_timer); | ||
845 | unregister_trace_block_plug(blk_add_trace_plug); | ||
846 | unregister_trace_block_sleeprq(blk_add_trace_sleeprq); | ||
847 | unregister_trace_block_getrq(blk_add_trace_getrq); | ||
848 | unregister_trace_block_bio_queue(blk_add_trace_bio_queue); | ||
849 | unregister_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge); | ||
850 | unregister_trace_block_bio_backmerge(blk_add_trace_bio_backmerge); | ||
851 | unregister_trace_block_bio_complete(blk_add_trace_bio_complete); | ||
852 | unregister_trace_block_bio_bounce(blk_add_trace_bio_bounce); | ||
853 | unregister_trace_block_rq_complete(blk_add_trace_rq_complete); | ||
854 | unregister_trace_block_rq_requeue(blk_add_trace_rq_requeue); | ||
855 | unregister_trace_block_rq_issue(blk_add_trace_rq_issue); | ||
856 | unregister_trace_block_rq_insert(blk_add_trace_rq_insert); | ||
857 | unregister_trace_block_rq_abort(blk_add_trace_rq_abort); | ||
858 | |||
859 | tracepoint_synchronize_unregister(); | ||
860 | } | ||