2 * Copyright (C) 2006 Jens Axboe <axboe@kernel.dk>
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.
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.
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
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/slab.h>
25 #include <linux/debugfs.h>
26 #include <linux/export.h>
27 #include <linux/time.h>
28 #include <linux/uaccess.h>
30 #include <trace/events/block.h>
32 #include "trace_output.h"
34 #ifdef CONFIG_BLK_DEV_IO_TRACE
36 static unsigned int blktrace_seq __read_mostly
= 1;
38 static struct trace_array
*blk_tr
;
39 static bool blk_tracer_enabled __read_mostly
;
41 /* Select an alternative, minimalistic output than the original one */
42 #define TRACE_BLK_OPT_CLASSIC 0x1
44 static struct tracer_opt blk_tracer_opts
[] = {
45 /* Default disable the minimalistic output */
46 { TRACER_OPT(blk_classic
, TRACE_BLK_OPT_CLASSIC
) },
50 static struct tracer_flags blk_tracer_flags
= {
52 .opts
= blk_tracer_opts
,
55 /* Global reference count of probes */
56 static atomic_t blk_probes_ref
= ATOMIC_INIT(0);
58 static void blk_register_tracepoints(void);
59 static void blk_unregister_tracepoints(void);
62 * Send out a notify message.
64 static void trace_note(struct blk_trace
*bt
, pid_t pid
, int action
,
65 const void *data
, size_t len
)
67 struct blk_io_trace
*t
;
68 struct ring_buffer_event
*event
= NULL
;
69 struct ring_buffer
*buffer
= NULL
;
71 int cpu
= smp_processor_id();
72 bool blk_tracer
= blk_tracer_enabled
;
75 buffer
= blk_tr
->buffer
;
77 event
= trace_buffer_lock_reserve(buffer
, TRACE_BLK
,
82 t
= ring_buffer_event_data(event
);
89 t
= relay_reserve(bt
->rchan
, sizeof(*t
) + len
);
91 t
->magic
= BLK_IO_TRACE_MAGIC
| BLK_IO_TRACE_VERSION
;
92 t
->time
= ktime_to_ns(ktime_get());
99 memcpy((void *) t
+ sizeof(*t
), data
, len
);
102 trace_buffer_unlock_commit(buffer
, event
, 0, pc
);
107 * Send out a notify for this process, if we haven't done so since a trace
110 static void trace_note_tsk(struct blk_trace
*bt
, struct task_struct
*tsk
)
112 tsk
->btrace_seq
= blktrace_seq
;
113 trace_note(bt
, tsk
->pid
, BLK_TN_PROCESS
, tsk
->comm
, sizeof(tsk
->comm
));
116 static void trace_note_time(struct blk_trace
*bt
)
122 getnstimeofday(&now
);
123 words
[0] = now
.tv_sec
;
124 words
[1] = now
.tv_nsec
;
126 local_irq_save(flags
);
127 trace_note(bt
, 0, BLK_TN_TIMESTAMP
, words
, sizeof(words
));
128 local_irq_restore(flags
);
131 void __trace_note_message(struct blk_trace
*bt
, const char *fmt
, ...)
138 if (unlikely(bt
->trace_state
!= Blktrace_running
&&
139 !blk_tracer_enabled
))
143 * If the BLK_TC_NOTIFY action mask isn't set, don't send any note
144 * message to the trace.
146 if (!(bt
->act_mask
& BLK_TC_NOTIFY
))
149 local_irq_save(flags
);
150 buf
= this_cpu_ptr(bt
->msg_data
);
152 n
= vscnprintf(buf
, BLK_TN_MAX_MSG
, fmt
, args
);
155 trace_note(bt
, 0, BLK_TN_MESSAGE
, buf
, n
);
156 local_irq_restore(flags
);
158 EXPORT_SYMBOL_GPL(__trace_note_message
);
160 static int act_log_check(struct blk_trace
*bt
, u32 what
, sector_t sector
,
163 if (((bt
->act_mask
<< BLK_TC_SHIFT
) & what
) == 0)
165 if (sector
&& (sector
< bt
->start_lba
|| sector
> bt
->end_lba
))
167 if (bt
->pid
&& pid
!= bt
->pid
)
174 * Data direction bit lookup
176 static const u32 ddir_act
[2] = { BLK_TC_ACT(BLK_TC_READ
),
177 BLK_TC_ACT(BLK_TC_WRITE
) };
179 #define BLK_TC_RAHEAD BLK_TC_AHEAD
181 /* The ilog2() calls fall out because they're constant */
182 #define MASK_TC_BIT(rw, __name) ((rw & REQ_ ## __name) << \
183 (ilog2(BLK_TC_ ## __name) + BLK_TC_SHIFT - __REQ_ ## __name))
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.
189 static void __blk_add_trace(struct blk_trace
*bt
, sector_t sector
, int bytes
,
190 int rw
, u32 what
, int error
, int pdu_len
, void *pdu_data
)
192 struct task_struct
*tsk
= current
;
193 struct ring_buffer_event
*event
= NULL
;
194 struct ring_buffer
*buffer
= NULL
;
195 struct blk_io_trace
*t
;
196 unsigned long flags
= 0;
197 unsigned long *sequence
;
200 bool blk_tracer
= blk_tracer_enabled
;
202 if (unlikely(bt
->trace_state
!= Blktrace_running
&& !blk_tracer
))
205 what
|= ddir_act
[rw
& WRITE
];
206 what
|= MASK_TC_BIT(rw
, SYNC
);
207 what
|= MASK_TC_BIT(rw
, RAHEAD
);
208 what
|= MASK_TC_BIT(rw
, META
);
209 what
|= MASK_TC_BIT(rw
, DISCARD
);
210 what
|= MASK_TC_BIT(rw
, FLUSH
);
211 what
|= MASK_TC_BIT(rw
, FUA
);
214 if (act_log_check(bt
, what
, sector
, pid
))
216 cpu
= raw_smp_processor_id();
219 tracing_record_cmdline(current
);
221 buffer
= blk_tr
->buffer
;
222 pc
= preempt_count();
223 event
= trace_buffer_lock_reserve(buffer
, TRACE_BLK
,
224 sizeof(*t
) + pdu_len
,
228 t
= ring_buffer_event_data(event
);
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
235 * from coming in and stepping on our toes.
237 local_irq_save(flags
);
239 if (unlikely(tsk
->btrace_seq
!= blktrace_seq
))
240 trace_note_tsk(bt
, tsk
);
242 t
= relay_reserve(bt
->rchan
, sizeof(*t
) + pdu_len
);
244 sequence
= per_cpu_ptr(bt
->sequence
, cpu
);
246 t
->magic
= BLK_IO_TRACE_MAGIC
| BLK_IO_TRACE_VERSION
;
247 t
->sequence
= ++(*sequence
);
248 t
->time
= ktime_to_ns(ktime_get());
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
264 t
->pdu_len
= pdu_len
;
267 memcpy((void *) t
+ sizeof(*t
), pdu_data
, pdu_len
);
270 trace_buffer_unlock_commit(buffer
, event
, 0, pc
);
275 local_irq_restore(flags
);
278 static struct dentry
*blk_tree_root
;
279 static DEFINE_MUTEX(blk_tree_mutex
);
281 static void blk_trace_free(struct blk_trace
*bt
)
283 debugfs_remove(bt
->msg_file
);
284 debugfs_remove(bt
->dropped_file
);
285 relay_close(bt
->rchan
);
286 debugfs_remove(bt
->dir
);
287 free_percpu(bt
->sequence
);
288 free_percpu(bt
->msg_data
);
292 static void blk_trace_cleanup(struct blk_trace
*bt
)
295 if (atomic_dec_and_test(&blk_probes_ref
))
296 blk_unregister_tracepoints();
299 int blk_trace_remove(struct request_queue
*q
)
301 struct blk_trace
*bt
;
303 bt
= xchg(&q
->blk_trace
, NULL
);
307 if (bt
->trace_state
!= Blktrace_running
)
308 blk_trace_cleanup(bt
);
312 EXPORT_SYMBOL_GPL(blk_trace_remove
);
314 static ssize_t
blk_dropped_read(struct file
*filp
, char __user
*buffer
,
315 size_t count
, loff_t
*ppos
)
317 struct blk_trace
*bt
= filp
->private_data
;
320 snprintf(buf
, sizeof(buf
), "%u\n", atomic_read(&bt
->dropped
));
322 return simple_read_from_buffer(buffer
, count
, ppos
, buf
, strlen(buf
));
325 static const struct file_operations blk_dropped_fops
= {
326 .owner
= THIS_MODULE
,
328 .read
= blk_dropped_read
,
329 .llseek
= default_llseek
,
332 static ssize_t
blk_msg_write(struct file
*filp
, const char __user
*buffer
,
333 size_t count
, loff_t
*ppos
)
336 struct blk_trace
*bt
;
338 if (count
>= BLK_TN_MAX_MSG
)
341 msg
= kmalloc(count
+ 1, GFP_KERNEL
);
345 if (copy_from_user(msg
, buffer
, count
)) {
351 bt
= filp
->private_data
;
352 __trace_note_message(bt
, "%s", msg
);
358 static const struct file_operations blk_msg_fops
= {
359 .owner
= THIS_MODULE
,
361 .write
= blk_msg_write
,
362 .llseek
= noop_llseek
,
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.
369 static int blk_subbuf_start_callback(struct rchan_buf
*buf
, void *subbuf
,
370 void *prev_subbuf
, size_t prev_padding
)
372 struct blk_trace
*bt
;
374 if (!relay_buf_full(buf
))
377 bt
= buf
->chan
->private_data
;
378 atomic_inc(&bt
->dropped
);
382 static int blk_remove_buf_file_callback(struct dentry
*dentry
)
384 debugfs_remove(dentry
);
389 static struct dentry
*blk_create_buf_file_callback(const char *filename
,
390 struct dentry
*parent
,
392 struct rchan_buf
*buf
,
395 return debugfs_create_file(filename
, mode
, parent
, buf
,
396 &relay_file_operations
);
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
,
405 static void blk_trace_setup_lba(struct blk_trace
*bt
,
406 struct block_device
*bdev
)
408 struct hd_struct
*part
= NULL
;
411 part
= bdev
->bd_part
;
414 bt
->start_lba
= part
->start_sect
;
415 bt
->end_lba
= part
->start_sect
+ part
->nr_sects
;
423 * Setup everything required to start tracing
425 int do_blk_trace_setup(struct request_queue
*q
, char *name
, dev_t dev
,
426 struct block_device
*bdev
,
427 struct blk_user_trace_setup
*buts
)
429 struct blk_trace
*old_bt
, *bt
= NULL
;
430 struct dentry
*dir
= NULL
;
433 if (!buts
->buf_size
|| !buts
->buf_nr
)
436 strncpy(buts
->name
, name
, BLKTRACE_BDEV_SIZE
);
437 buts
->name
[BLKTRACE_BDEV_SIZE
- 1] = '\0';
440 * some device names have larger paths - convert the slashes
441 * to underscores for this to work as expected
443 for (i
= 0; i
< strlen(buts
->name
); i
++)
444 if (buts
->name
[i
] == '/')
447 bt
= kzalloc(sizeof(*bt
), GFP_KERNEL
);
452 bt
->sequence
= alloc_percpu(unsigned long);
456 bt
->msg_data
= __alloc_percpu(BLK_TN_MAX_MSG
, __alignof__(char));
462 mutex_lock(&blk_tree_mutex
);
463 if (!blk_tree_root
) {
464 blk_tree_root
= debugfs_create_dir("block", NULL
);
465 if (!blk_tree_root
) {
466 mutex_unlock(&blk_tree_mutex
);
470 mutex_unlock(&blk_tree_mutex
);
472 dir
= debugfs_create_dir(buts
->name
, blk_tree_root
);
479 atomic_set(&bt
->dropped
, 0);
482 bt
->dropped_file
= debugfs_create_file("dropped", 0444, dir
, bt
,
484 if (!bt
->dropped_file
)
487 bt
->msg_file
= debugfs_create_file("msg", 0222, dir
, bt
, &blk_msg_fops
);
491 bt
->rchan
= relay_open("trace", dir
, buts
->buf_size
,
492 buts
->buf_nr
, &blk_relay_callbacks
, bt
);
496 bt
->act_mask
= buts
->act_mask
;
498 bt
->act_mask
= (u16
) -1;
500 blk_trace_setup_lba(bt
, bdev
);
502 /* overwrite with user settings */
504 bt
->start_lba
= buts
->start_lba
;
506 bt
->end_lba
= buts
->end_lba
;
509 bt
->trace_state
= Blktrace_setup
;
512 old_bt
= xchg(&q
->blk_trace
, bt
);
514 (void) xchg(&q
->blk_trace
, old_bt
);
518 if (atomic_inc_return(&blk_probes_ref
) == 1)
519 blk_register_tracepoints();
527 int blk_trace_setup(struct request_queue
*q
, char *name
, dev_t dev
,
528 struct block_device
*bdev
,
531 struct blk_user_trace_setup buts
;
534 ret
= copy_from_user(&buts
, arg
, sizeof(buts
));
538 ret
= do_blk_trace_setup(q
, name
, dev
, bdev
, &buts
);
542 if (copy_to_user(arg
, &buts
, sizeof(buts
))) {
548 EXPORT_SYMBOL_GPL(blk_trace_setup
);
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
,
555 struct blk_user_trace_setup buts
;
556 struct compat_blk_user_trace_setup cbuts
;
559 if (copy_from_user(&cbuts
, arg
, sizeof(cbuts
)))
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
,
570 memcpy(&buts
.name
, &cbuts
.name
, 32);
572 ret
= do_blk_trace_setup(q
, name
, dev
, bdev
, &buts
);
576 if (copy_to_user(arg
, &buts
.name
, 32)) {
585 int blk_trace_startstop(struct request_queue
*q
, int start
)
588 struct blk_trace
*bt
= q
->blk_trace
;
594 * For starting a trace, we can transition from a setup or stopped
595 * trace. For stopping a trace, the state must be running
599 if (bt
->trace_state
== Blktrace_setup
||
600 bt
->trace_state
== Blktrace_stopped
) {
603 bt
->trace_state
= Blktrace_running
;
609 if (bt
->trace_state
== Blktrace_running
) {
610 bt
->trace_state
= Blktrace_stopped
;
611 relay_flush(bt
->rchan
);
618 EXPORT_SYMBOL_GPL(blk_trace_startstop
);
621 * blk_trace_ioctl: - handle the ioctls associated with tracing
622 * @bdev: the block device
623 * @cmd: the ioctl cmd
624 * @arg: the argument data, if any
627 int blk_trace_ioctl(struct block_device
*bdev
, unsigned cmd
, char __user
*arg
)
629 struct request_queue
*q
;
631 char b
[BDEVNAME_SIZE
];
633 q
= bdev_get_queue(bdev
);
637 mutex_lock(&bdev
->bd_mutex
);
642 ret
= blk_trace_setup(q
, b
, bdev
->bd_dev
, bdev
, arg
);
644 #if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64)
645 case BLKTRACESETUP32
:
647 ret
= compat_blk_trace_setup(q
, b
, bdev
->bd_dev
, bdev
, arg
);
653 ret
= blk_trace_startstop(q
, start
);
655 case BLKTRACETEARDOWN
:
656 ret
= blk_trace_remove(q
);
663 mutex_unlock(&bdev
->bd_mutex
);
668 * blk_trace_shutdown: - stop and cleanup trace structures
669 * @q: the request queue associated with the device
672 void blk_trace_shutdown(struct request_queue
*q
)
675 blk_trace_startstop(q
, 0);
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
691 * Records an action against a request. Will log the bio offset + size.
694 static void blk_add_trace_rq(struct request_queue
*q
, struct request
*rq
,
697 struct blk_trace
*bt
= q
->blk_trace
;
702 if (rq
->cmd_type
== REQ_TYPE_BLOCK_PC
) {
703 what
|= BLK_TC_ACT(BLK_TC_PC
);
704 __blk_add_trace(bt
, 0, blk_rq_bytes(rq
), rq
->cmd_flags
,
705 what
, rq
->errors
, rq
->cmd_len
, rq
->cmd
);
707 what
|= BLK_TC_ACT(BLK_TC_FS
);
708 __blk_add_trace(bt
, blk_rq_pos(rq
), blk_rq_bytes(rq
),
709 rq
->cmd_flags
, what
, rq
->errors
, 0, NULL
);
713 static void blk_add_trace_rq_abort(void *ignore
,
714 struct request_queue
*q
, struct request
*rq
)
716 blk_add_trace_rq(q
, rq
, BLK_TA_ABORT
);
719 static void blk_add_trace_rq_insert(void *ignore
,
720 struct request_queue
*q
, struct request
*rq
)
722 blk_add_trace_rq(q
, rq
, BLK_TA_INSERT
);
725 static void blk_add_trace_rq_issue(void *ignore
,
726 struct request_queue
*q
, struct request
*rq
)
728 blk_add_trace_rq(q
, rq
, BLK_TA_ISSUE
);
731 static void blk_add_trace_rq_requeue(void *ignore
,
732 struct request_queue
*q
,
735 blk_add_trace_rq(q
, rq
, BLK_TA_REQUEUE
);
738 static void blk_add_trace_rq_complete(void *ignore
,
739 struct request_queue
*q
,
742 struct blk_trace
*bt
= q
->blk_trace
;
744 /* if control ever passes through here, it's a request based driver */
745 if (unlikely(bt
&& !bt
->rq_based
))
748 blk_add_trace_rq(q
, rq
, BLK_TA_COMPLETE
);
752 * blk_add_trace_bio - Add a trace for a bio oriented action
753 * @q: queue the io is for
754 * @bio: the source bio
756 * @error: error, if any
759 * Records an action against a bio. Will log the bio offset + size.
762 static void blk_add_trace_bio(struct request_queue
*q
, struct bio
*bio
,
765 struct blk_trace
*bt
= q
->blk_trace
;
770 if (!error
&& !bio_flagged(bio
, BIO_UPTODATE
))
773 __blk_add_trace(bt
, bio
->bi_sector
, bio
->bi_size
, bio
->bi_rw
, what
,
777 static void blk_add_trace_bio_bounce(void *ignore
,
778 struct request_queue
*q
, struct bio
*bio
)
780 blk_add_trace_bio(q
, bio
, BLK_TA_BOUNCE
, 0);
783 static void blk_add_trace_bio_complete(void *ignore
, struct bio
*bio
, int error
)
785 struct request_queue
*q
;
786 struct blk_trace
*bt
;
791 q
= bdev_get_queue(bio
->bi_bdev
);
795 * Request based drivers will generate both rq and bio completions.
798 if (likely(!bt
) || bt
->rq_based
)
801 blk_add_trace_bio(q
, bio
, BLK_TA_COMPLETE
, error
);
804 static void blk_add_trace_bio_backmerge(void *ignore
,
805 struct request_queue
*q
,
809 blk_add_trace_bio(q
, bio
, BLK_TA_BACKMERGE
, 0);
812 static void blk_add_trace_bio_frontmerge(void *ignore
,
813 struct request_queue
*q
,
817 blk_add_trace_bio(q
, bio
, BLK_TA_FRONTMERGE
, 0);
820 static void blk_add_trace_bio_queue(void *ignore
,
821 struct request_queue
*q
, struct bio
*bio
)
823 blk_add_trace_bio(q
, bio
, BLK_TA_QUEUE
, 0);
826 static void blk_add_trace_getrq(void *ignore
,
827 struct request_queue
*q
,
828 struct bio
*bio
, int rw
)
831 blk_add_trace_bio(q
, bio
, BLK_TA_GETRQ
, 0);
833 struct blk_trace
*bt
= q
->blk_trace
;
836 __blk_add_trace(bt
, 0, 0, rw
, BLK_TA_GETRQ
, 0, 0, NULL
);
841 static void blk_add_trace_sleeprq(void *ignore
,
842 struct request_queue
*q
,
843 struct bio
*bio
, int rw
)
846 blk_add_trace_bio(q
, bio
, BLK_TA_SLEEPRQ
, 0);
848 struct blk_trace
*bt
= q
->blk_trace
;
851 __blk_add_trace(bt
, 0, 0, rw
, BLK_TA_SLEEPRQ
,
856 static void blk_add_trace_plug(void *ignore
, struct request_queue
*q
)
858 struct blk_trace
*bt
= q
->blk_trace
;
861 __blk_add_trace(bt
, 0, 0, 0, BLK_TA_PLUG
, 0, 0, NULL
);
864 static void blk_add_trace_unplug(void *ignore
, struct request_queue
*q
,
865 unsigned int depth
, bool explicit)
867 struct blk_trace
*bt
= q
->blk_trace
;
870 __be64 rpdu
= cpu_to_be64(depth
);
874 what
= BLK_TA_UNPLUG_IO
;
876 what
= BLK_TA_UNPLUG_TIMER
;
878 __blk_add_trace(bt
, 0, 0, 0, what
, 0, sizeof(rpdu
), &rpdu
);
882 static void blk_add_trace_split(void *ignore
,
883 struct request_queue
*q
, struct bio
*bio
,
886 struct blk_trace
*bt
= q
->blk_trace
;
889 __be64 rpdu
= cpu_to_be64(pdu
);
891 __blk_add_trace(bt
, bio
->bi_sector
, bio
->bi_size
, bio
->bi_rw
,
892 BLK_TA_SPLIT
, !bio_flagged(bio
, BIO_UPTODATE
),
893 sizeof(rpdu
), &rpdu
);
898 * blk_add_trace_bio_remap - Add a trace for a bio-remap operation
899 * @ignore: trace callback data parameter (not used)
900 * @q: queue the io is for
901 * @bio: the source bio
902 * @dev: target device
903 * @from: source sector
906 * Device mapper or raid target sometimes need to split a bio because
907 * it spans a stripe (or similar). Add a trace for that action.
910 static void blk_add_trace_bio_remap(void *ignore
,
911 struct request_queue
*q
, struct bio
*bio
,
912 dev_t dev
, sector_t from
)
914 struct blk_trace
*bt
= q
->blk_trace
;
915 struct blk_io_trace_remap r
;
920 r
.device_from
= cpu_to_be32(dev
);
921 r
.device_to
= cpu_to_be32(bio
->bi_bdev
->bd_dev
);
922 r
.sector_from
= cpu_to_be64(from
);
924 __blk_add_trace(bt
, bio
->bi_sector
, bio
->bi_size
, bio
->bi_rw
,
925 BLK_TA_REMAP
, !bio_flagged(bio
, BIO_UPTODATE
),
930 * blk_add_trace_rq_remap - Add a trace for a request-remap operation
931 * @ignore: trace callback data parameter (not used)
932 * @q: queue the io is for
933 * @rq: the source request
934 * @dev: target device
935 * @from: source sector
938 * Device mapper remaps request to other devices.
939 * Add a trace for that action.
942 static void blk_add_trace_rq_remap(void *ignore
,
943 struct request_queue
*q
,
944 struct request
*rq
, dev_t dev
,
947 struct blk_trace
*bt
= q
->blk_trace
;
948 struct blk_io_trace_remap r
;
953 r
.device_from
= cpu_to_be32(dev
);
954 r
.device_to
= cpu_to_be32(disk_devt(rq
->rq_disk
));
955 r
.sector_from
= cpu_to_be64(from
);
957 __blk_add_trace(bt
, blk_rq_pos(rq
), blk_rq_bytes(rq
),
958 rq_data_dir(rq
), BLK_TA_REMAP
, !!rq
->errors
,
963 * blk_add_driver_data - Add binary message with driver-specific data
964 * @q: queue the io is for
966 * @data: driver-specific data
967 * @len: length of driver-specific data
970 * Some drivers might want to write driver-specific data per request.
973 void blk_add_driver_data(struct request_queue
*q
,
975 void *data
, size_t len
)
977 struct blk_trace
*bt
= q
->blk_trace
;
982 if (rq
->cmd_type
== REQ_TYPE_BLOCK_PC
)
983 __blk_add_trace(bt
, 0, blk_rq_bytes(rq
), 0,
984 BLK_TA_DRV_DATA
, rq
->errors
, len
, data
);
986 __blk_add_trace(bt
, blk_rq_pos(rq
), blk_rq_bytes(rq
), 0,
987 BLK_TA_DRV_DATA
, rq
->errors
, len
, data
);
989 EXPORT_SYMBOL_GPL(blk_add_driver_data
);
991 static void blk_register_tracepoints(void)
995 ret
= register_trace_block_rq_abort(blk_add_trace_rq_abort
, NULL
);
997 ret
= register_trace_block_rq_insert(blk_add_trace_rq_insert
, NULL
);
999 ret
= register_trace_block_rq_issue(blk_add_trace_rq_issue
, NULL
);
1001 ret
= register_trace_block_rq_requeue(blk_add_trace_rq_requeue
, NULL
);
1003 ret
= register_trace_block_rq_complete(blk_add_trace_rq_complete
, NULL
);
1005 ret
= register_trace_block_bio_bounce(blk_add_trace_bio_bounce
, NULL
);
1007 ret
= register_trace_block_bio_complete(blk_add_trace_bio_complete
, NULL
);
1009 ret
= register_trace_block_bio_backmerge(blk_add_trace_bio_backmerge
, NULL
);
1011 ret
= register_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge
, NULL
);
1013 ret
= register_trace_block_bio_queue(blk_add_trace_bio_queue
, NULL
);
1015 ret
= register_trace_block_getrq(blk_add_trace_getrq
, NULL
);
1017 ret
= register_trace_block_sleeprq(blk_add_trace_sleeprq
, NULL
);
1019 ret
= register_trace_block_plug(blk_add_trace_plug
, NULL
);
1021 ret
= register_trace_block_unplug(blk_add_trace_unplug
, NULL
);
1023 ret
= register_trace_block_split(blk_add_trace_split
, NULL
);
1025 ret
= register_trace_block_bio_remap(blk_add_trace_bio_remap
, NULL
);
1027 ret
= register_trace_block_rq_remap(blk_add_trace_rq_remap
, NULL
);
1031 static void blk_unregister_tracepoints(void)
1033 unregister_trace_block_rq_remap(blk_add_trace_rq_remap
, NULL
);
1034 unregister_trace_block_bio_remap(blk_add_trace_bio_remap
, NULL
);
1035 unregister_trace_block_split(blk_add_trace_split
, NULL
);
1036 unregister_trace_block_unplug(blk_add_trace_unplug
, NULL
);
1037 unregister_trace_block_plug(blk_add_trace_plug
, NULL
);
1038 unregister_trace_block_sleeprq(blk_add_trace_sleeprq
, NULL
);
1039 unregister_trace_block_getrq(blk_add_trace_getrq
, NULL
);
1040 unregister_trace_block_bio_queue(blk_add_trace_bio_queue
, NULL
);
1041 unregister_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge
, NULL
);
1042 unregister_trace_block_bio_backmerge(blk_add_trace_bio_backmerge
, NULL
);
1043 unregister_trace_block_bio_complete(blk_add_trace_bio_complete
, NULL
);
1044 unregister_trace_block_bio_bounce(blk_add_trace_bio_bounce
, NULL
);
1045 unregister_trace_block_rq_complete(blk_add_trace_rq_complete
, NULL
);
1046 unregister_trace_block_rq_requeue(blk_add_trace_rq_requeue
, NULL
);
1047 unregister_trace_block_rq_issue(blk_add_trace_rq_issue
, NULL
);
1048 unregister_trace_block_rq_insert(blk_add_trace_rq_insert
, NULL
);
1049 unregister_trace_block_rq_abort(blk_add_trace_rq_abort
, NULL
);
1051 tracepoint_synchronize_unregister();
1055 * struct blk_io_tracer formatting routines
1058 static void fill_rwbs(char *rwbs
, const struct blk_io_trace
*t
)
1061 int tc
= t
->action
>> BLK_TC_SHIFT
;
1063 if (t
->action
== BLK_TN_MESSAGE
) {
1068 if (tc
& BLK_TC_FLUSH
)
1071 if (tc
& BLK_TC_DISCARD
)
1073 else if (tc
& BLK_TC_WRITE
)
1080 if (tc
& BLK_TC_FUA
)
1082 if (tc
& BLK_TC_AHEAD
)
1084 if (tc
& BLK_TC_SYNC
)
1086 if (tc
& BLK_TC_META
)
1093 const struct blk_io_trace
*te_blk_io_trace(const struct trace_entry
*ent
)
1095 return (const struct blk_io_trace
*)ent
;
1098 static inline const void *pdu_start(const struct trace_entry
*ent
)
1100 return te_blk_io_trace(ent
) + 1;
1103 static inline u32
t_action(const struct trace_entry
*ent
)
1105 return te_blk_io_trace(ent
)->action
;
1108 static inline u32
t_bytes(const struct trace_entry
*ent
)
1110 return te_blk_io_trace(ent
)->bytes
;
1113 static inline u32
t_sec(const struct trace_entry
*ent
)
1115 return te_blk_io_trace(ent
)->bytes
>> 9;
1118 static inline unsigned long long t_sector(const struct trace_entry
*ent
)
1120 return te_blk_io_trace(ent
)->sector
;
1123 static inline __u16
t_error(const struct trace_entry
*ent
)
1125 return te_blk_io_trace(ent
)->error
;
1128 static __u64
get_pdu_int(const struct trace_entry
*ent
)
1130 const __u64
*val
= pdu_start(ent
);
1131 return be64_to_cpu(*val
);
1134 static void get_pdu_remap(const struct trace_entry
*ent
,
1135 struct blk_io_trace_remap
*r
)
1137 const struct blk_io_trace_remap
*__r
= pdu_start(ent
);
1138 __u64 sector_from
= __r
->sector_from
;
1140 r
->device_from
= be32_to_cpu(__r
->device_from
);
1141 r
->device_to
= be32_to_cpu(__r
->device_to
);
1142 r
->sector_from
= be64_to_cpu(sector_from
);
1145 typedef int (blk_log_action_t
) (struct trace_iterator
*iter
, const char *act
);
1147 static int blk_log_action_classic(struct trace_iterator
*iter
, const char *act
)
1149 char rwbs
[RWBS_LEN
];
1150 unsigned long long ts
= iter
->ts
;
1151 unsigned long nsec_rem
= do_div(ts
, NSEC_PER_SEC
);
1152 unsigned secs
= (unsigned long)ts
;
1153 const struct blk_io_trace
*t
= te_blk_io_trace(iter
->ent
);
1157 return trace_seq_printf(&iter
->seq
,
1158 "%3d,%-3d %2d %5d.%09lu %5u %2s %3s ",
1159 MAJOR(t
->device
), MINOR(t
->device
), iter
->cpu
,
1160 secs
, nsec_rem
, iter
->ent
->pid
, act
, rwbs
);
1163 static int blk_log_action(struct trace_iterator
*iter
, const char *act
)
1165 char rwbs
[RWBS_LEN
];
1166 const struct blk_io_trace
*t
= te_blk_io_trace(iter
->ent
);
1169 return trace_seq_printf(&iter
->seq
, "%3d,%-3d %2s %3s ",
1170 MAJOR(t
->device
), MINOR(t
->device
), act
, rwbs
);
1173 static int blk_log_dump_pdu(struct trace_seq
*s
, const struct trace_entry
*ent
)
1175 const unsigned char *pdu_buf
;
1179 pdu_buf
= pdu_start(ent
);
1180 pdu_len
= te_blk_io_trace(ent
)->pdu_len
;
1185 /* find the last zero that needs to be printed */
1186 for (end
= pdu_len
- 1; end
>= 0; end
--)
1191 if (!trace_seq_putc(s
, '('))
1194 for (i
= 0; i
< pdu_len
; i
++) {
1196 ret
= trace_seq_printf(s
, "%s%02x",
1197 i
== 0 ? "" : " ", pdu_buf
[i
]);
1202 * stop when the rest is just zeroes and indicate so
1203 * with a ".." appended
1205 if (i
== end
&& end
!= pdu_len
- 1)
1206 return trace_seq_puts(s
, " ..) ");
1209 return trace_seq_puts(s
, ") ");
1212 static int blk_log_generic(struct trace_seq
*s
, const struct trace_entry
*ent
)
1214 char cmd
[TASK_COMM_LEN
];
1216 trace_find_cmdline(ent
->pid
, cmd
);
1218 if (t_action(ent
) & BLK_TC_ACT(BLK_TC_PC
)) {
1221 ret
= trace_seq_printf(s
, "%u ", t_bytes(ent
));
1224 ret
= blk_log_dump_pdu(s
, ent
);
1227 return trace_seq_printf(s
, "[%s]\n", cmd
);
1230 return trace_seq_printf(s
, "%llu + %u [%s]\n",
1231 t_sector(ent
), t_sec(ent
), cmd
);
1232 return trace_seq_printf(s
, "[%s]\n", cmd
);
1236 static int blk_log_with_error(struct trace_seq
*s
,
1237 const struct trace_entry
*ent
)
1239 if (t_action(ent
) & BLK_TC_ACT(BLK_TC_PC
)) {
1242 ret
= blk_log_dump_pdu(s
, ent
);
1244 return trace_seq_printf(s
, "[%d]\n", t_error(ent
));
1248 return trace_seq_printf(s
, "%llu + %u [%d]\n",
1250 t_sec(ent
), t_error(ent
));
1251 return trace_seq_printf(s
, "%llu [%d]\n",
1252 t_sector(ent
), t_error(ent
));
1256 static int blk_log_remap(struct trace_seq
*s
, const struct trace_entry
*ent
)
1258 struct blk_io_trace_remap r
= { .device_from
= 0, };
1260 get_pdu_remap(ent
, &r
);
1261 return trace_seq_printf(s
, "%llu + %u <- (%d,%d) %llu\n",
1262 t_sector(ent
), t_sec(ent
),
1263 MAJOR(r
.device_from
), MINOR(r
.device_from
),
1264 (unsigned long long)r
.sector_from
);
1267 static int blk_log_plug(struct trace_seq
*s
, const struct trace_entry
*ent
)
1269 char cmd
[TASK_COMM_LEN
];
1271 trace_find_cmdline(ent
->pid
, cmd
);
1273 return trace_seq_printf(s
, "[%s]\n", cmd
);
1276 static int blk_log_unplug(struct trace_seq
*s
, const struct trace_entry
*ent
)
1278 char cmd
[TASK_COMM_LEN
];
1280 trace_find_cmdline(ent
->pid
, cmd
);
1282 return trace_seq_printf(s
, "[%s] %llu\n", cmd
, get_pdu_int(ent
));
1285 static int blk_log_split(struct trace_seq
*s
, const struct trace_entry
*ent
)
1287 char cmd
[TASK_COMM_LEN
];
1289 trace_find_cmdline(ent
->pid
, cmd
);
1291 return trace_seq_printf(s
, "%llu / %llu [%s]\n", t_sector(ent
),
1292 get_pdu_int(ent
), cmd
);
1295 static int blk_log_msg(struct trace_seq
*s
, const struct trace_entry
*ent
)
1298 const struct blk_io_trace
*t
= te_blk_io_trace(ent
);
1300 ret
= trace_seq_putmem(s
, t
+ 1, t
->pdu_len
);
1302 return trace_seq_putc(s
, '\n');
1307 * struct tracer operations
1310 static void blk_tracer_print_header(struct seq_file
*m
)
1312 if (!(blk_tracer_flags
.val
& TRACE_BLK_OPT_CLASSIC
))
1314 seq_puts(m
, "# DEV CPU TIMESTAMP PID ACT FLG\n"
1318 static void blk_tracer_start(struct trace_array
*tr
)
1320 blk_tracer_enabled
= true;
1323 static int blk_tracer_init(struct trace_array
*tr
)
1326 blk_tracer_start(tr
);
1330 static void blk_tracer_stop(struct trace_array
*tr
)
1332 blk_tracer_enabled
= false;
1335 static void blk_tracer_reset(struct trace_array
*tr
)
1337 blk_tracer_stop(tr
);
1340 static const struct {
1342 int (*print
)(struct trace_seq
*s
, const struct trace_entry
*ent
);
1344 [__BLK_TA_QUEUE
] = {{ "Q", "queue" }, blk_log_generic
},
1345 [__BLK_TA_BACKMERGE
] = {{ "M", "backmerge" }, blk_log_generic
},
1346 [__BLK_TA_FRONTMERGE
] = {{ "F", "frontmerge" }, blk_log_generic
},
1347 [__BLK_TA_GETRQ
] = {{ "G", "getrq" }, blk_log_generic
},
1348 [__BLK_TA_SLEEPRQ
] = {{ "S", "sleeprq" }, blk_log_generic
},
1349 [__BLK_TA_REQUEUE
] = {{ "R", "requeue" }, blk_log_with_error
},
1350 [__BLK_TA_ISSUE
] = {{ "D", "issue" }, blk_log_generic
},
1351 [__BLK_TA_COMPLETE
] = {{ "C", "complete" }, blk_log_with_error
},
1352 [__BLK_TA_PLUG
] = {{ "P", "plug" }, blk_log_plug
},
1353 [__BLK_TA_UNPLUG_IO
] = {{ "U", "unplug_io" }, blk_log_unplug
},
1354 [__BLK_TA_UNPLUG_TIMER
] = {{ "UT", "unplug_timer" }, blk_log_unplug
},
1355 [__BLK_TA_INSERT
] = {{ "I", "insert" }, blk_log_generic
},
1356 [__BLK_TA_SPLIT
] = {{ "X", "split" }, blk_log_split
},
1357 [__BLK_TA_BOUNCE
] = {{ "B", "bounce" }, blk_log_generic
},
1358 [__BLK_TA_REMAP
] = {{ "A", "remap" }, blk_log_remap
},
1361 static enum print_line_t
print_one_line(struct trace_iterator
*iter
,
1364 struct trace_seq
*s
= &iter
->seq
;
1365 const struct blk_io_trace
*t
;
1369 blk_log_action_t
*log_action
;
1371 t
= te_blk_io_trace(iter
->ent
);
1372 what
= t
->action
& ((1 << BLK_TC_SHIFT
) - 1);
1373 long_act
= !!(trace_flags
& TRACE_ITER_VERBOSE
);
1374 log_action
= classic
? &blk_log_action_classic
: &blk_log_action
;
1376 if (t
->action
== BLK_TN_MESSAGE
) {
1377 ret
= log_action(iter
, long_act
? "message" : "m");
1379 ret
= blk_log_msg(s
, iter
->ent
);
1383 if (unlikely(what
== 0 || what
>= ARRAY_SIZE(what2act
)))
1384 ret
= trace_seq_printf(s
, "Unknown action %x\n", what
);
1386 ret
= log_action(iter
, what2act
[what
].act
[long_act
]);
1388 ret
= what2act
[what
].print(s
, iter
->ent
);
1391 return ret
? TRACE_TYPE_HANDLED
: TRACE_TYPE_PARTIAL_LINE
;
1394 static enum print_line_t
blk_trace_event_print(struct trace_iterator
*iter
,
1395 int flags
, struct trace_event
*event
)
1397 return print_one_line(iter
, false);
1400 static int blk_trace_synthesize_old_trace(struct trace_iterator
*iter
)
1402 struct trace_seq
*s
= &iter
->seq
;
1403 struct blk_io_trace
*t
= (struct blk_io_trace
*)iter
->ent
;
1404 const int offset
= offsetof(struct blk_io_trace
, sector
);
1405 struct blk_io_trace old
= {
1406 .magic
= BLK_IO_TRACE_MAGIC
| BLK_IO_TRACE_VERSION
,
1410 if (!trace_seq_putmem(s
, &old
, offset
))
1412 return trace_seq_putmem(s
, &t
->sector
,
1413 sizeof(old
) - offset
+ t
->pdu_len
);
1416 static enum print_line_t
1417 blk_trace_event_print_binary(struct trace_iterator
*iter
, int flags
,
1418 struct trace_event
*event
)
1420 return blk_trace_synthesize_old_trace(iter
) ?
1421 TRACE_TYPE_HANDLED
: TRACE_TYPE_PARTIAL_LINE
;
1424 static enum print_line_t
blk_tracer_print_line(struct trace_iterator
*iter
)
1426 if (!(blk_tracer_flags
.val
& TRACE_BLK_OPT_CLASSIC
))
1427 return TRACE_TYPE_UNHANDLED
;
1429 return print_one_line(iter
, true);
1432 static int blk_tracer_set_flag(u32 old_flags
, u32 bit
, int set
)
1434 /* don't output context-info for blk_classic output */
1435 if (bit
== TRACE_BLK_OPT_CLASSIC
) {
1437 trace_flags
&= ~TRACE_ITER_CONTEXT_INFO
;
1439 trace_flags
|= TRACE_ITER_CONTEXT_INFO
;
1444 static struct tracer blk_tracer __read_mostly
= {
1446 .init
= blk_tracer_init
,
1447 .reset
= blk_tracer_reset
,
1448 .start
= blk_tracer_start
,
1449 .stop
= blk_tracer_stop
,
1450 .print_header
= blk_tracer_print_header
,
1451 .print_line
= blk_tracer_print_line
,
1452 .flags
= &blk_tracer_flags
,
1453 .set_flag
= blk_tracer_set_flag
,
1456 static struct trace_event_functions trace_blk_event_funcs
= {
1457 .trace
= blk_trace_event_print
,
1458 .binary
= blk_trace_event_print_binary
,
1461 static struct trace_event trace_blk_event
= {
1463 .funcs
= &trace_blk_event_funcs
,
1466 static int __init
init_blk_tracer(void)
1468 if (!register_ftrace_event(&trace_blk_event
)) {
1469 pr_warning("Warning: could not register block events\n");
1473 if (register_tracer(&blk_tracer
) != 0) {
1474 pr_warning("Warning: could not register the block tracer\n");
1475 unregister_ftrace_event(&trace_blk_event
);
1482 device_initcall(init_blk_tracer
);
1484 static int blk_trace_remove_queue(struct request_queue
*q
)
1486 struct blk_trace
*bt
;
1488 bt
= xchg(&q
->blk_trace
, NULL
);
1492 if (atomic_dec_and_test(&blk_probes_ref
))
1493 blk_unregister_tracepoints();
1500 * Setup everything required to start tracing
1502 static int blk_trace_setup_queue(struct request_queue
*q
,
1503 struct block_device
*bdev
)
1505 struct blk_trace
*old_bt
, *bt
= NULL
;
1508 bt
= kzalloc(sizeof(*bt
), GFP_KERNEL
);
1512 bt
->msg_data
= __alloc_percpu(BLK_TN_MAX_MSG
, __alignof__(char));
1516 bt
->dev
= bdev
->bd_dev
;
1517 bt
->act_mask
= (u16
)-1;
1519 blk_trace_setup_lba(bt
, bdev
);
1521 old_bt
= xchg(&q
->blk_trace
, bt
);
1522 if (old_bt
!= NULL
) {
1523 (void)xchg(&q
->blk_trace
, old_bt
);
1528 if (atomic_inc_return(&blk_probes_ref
) == 1)
1529 blk_register_tracepoints();
1538 * sysfs interface to enable and configure tracing
1541 static ssize_t
sysfs_blk_trace_attr_show(struct device
*dev
,
1542 struct device_attribute
*attr
,
1544 static ssize_t
sysfs_blk_trace_attr_store(struct device
*dev
,
1545 struct device_attribute
*attr
,
1546 const char *buf
, size_t count
);
1547 #define BLK_TRACE_DEVICE_ATTR(_name) \
1548 DEVICE_ATTR(_name, S_IRUGO | S_IWUSR, \
1549 sysfs_blk_trace_attr_show, \
1550 sysfs_blk_trace_attr_store)
1552 static BLK_TRACE_DEVICE_ATTR(enable
);
1553 static BLK_TRACE_DEVICE_ATTR(act_mask
);
1554 static BLK_TRACE_DEVICE_ATTR(pid
);
1555 static BLK_TRACE_DEVICE_ATTR(start_lba
);
1556 static BLK_TRACE_DEVICE_ATTR(end_lba
);
1558 static struct attribute
*blk_trace_attrs
[] = {
1559 &dev_attr_enable
.attr
,
1560 &dev_attr_act_mask
.attr
,
1562 &dev_attr_start_lba
.attr
,
1563 &dev_attr_end_lba
.attr
,
1567 struct attribute_group blk_trace_attr_group
= {
1569 .attrs
= blk_trace_attrs
,
1572 static const struct {
1576 { BLK_TC_READ
, "read" },
1577 { BLK_TC_WRITE
, "write" },
1578 { BLK_TC_FLUSH
, "flush" },
1579 { BLK_TC_SYNC
, "sync" },
1580 { BLK_TC_QUEUE
, "queue" },
1581 { BLK_TC_REQUEUE
, "requeue" },
1582 { BLK_TC_ISSUE
, "issue" },
1583 { BLK_TC_COMPLETE
, "complete" },
1584 { BLK_TC_FS
, "fs" },
1585 { BLK_TC_PC
, "pc" },
1586 { BLK_TC_AHEAD
, "ahead" },
1587 { BLK_TC_META
, "meta" },
1588 { BLK_TC_DISCARD
, "discard" },
1589 { BLK_TC_DRV_DATA
, "drv_data" },
1590 { BLK_TC_FUA
, "fua" },
1593 static int blk_trace_str2mask(const char *str
)
1597 char *buf
, *s
, *token
;
1599 buf
= kstrdup(str
, GFP_KERNEL
);
1605 token
= strsep(&s
, ",");
1612 for (i
= 0; i
< ARRAY_SIZE(mask_maps
); i
++) {
1613 if (strcasecmp(token
, mask_maps
[i
].str
) == 0) {
1614 mask
|= mask_maps
[i
].mask
;
1618 if (i
== ARRAY_SIZE(mask_maps
)) {
1628 static ssize_t
blk_trace_mask2str(char *buf
, int mask
)
1633 for (i
= 0; i
< ARRAY_SIZE(mask_maps
); i
++) {
1634 if (mask
& mask_maps
[i
].mask
) {
1635 p
+= sprintf(p
, "%s%s",
1636 (p
== buf
) ? "" : ",", mask_maps
[i
].str
);
1644 static struct request_queue
*blk_trace_get_queue(struct block_device
*bdev
)
1646 if (bdev
->bd_disk
== NULL
)
1649 return bdev_get_queue(bdev
);
1652 static ssize_t
sysfs_blk_trace_attr_show(struct device
*dev
,
1653 struct device_attribute
*attr
,
1656 struct hd_struct
*p
= dev_to_part(dev
);
1657 struct request_queue
*q
;
1658 struct block_device
*bdev
;
1659 ssize_t ret
= -ENXIO
;
1661 bdev
= bdget(part_devt(p
));
1665 q
= blk_trace_get_queue(bdev
);
1669 mutex_lock(&bdev
->bd_mutex
);
1671 if (attr
== &dev_attr_enable
) {
1672 ret
= sprintf(buf
, "%u\n", !!q
->blk_trace
);
1673 goto out_unlock_bdev
;
1676 if (q
->blk_trace
== NULL
)
1677 ret
= sprintf(buf
, "disabled\n");
1678 else if (attr
== &dev_attr_act_mask
)
1679 ret
= blk_trace_mask2str(buf
, q
->blk_trace
->act_mask
);
1680 else if (attr
== &dev_attr_pid
)
1681 ret
= sprintf(buf
, "%u\n", q
->blk_trace
->pid
);
1682 else if (attr
== &dev_attr_start_lba
)
1683 ret
= sprintf(buf
, "%llu\n", q
->blk_trace
->start_lba
);
1684 else if (attr
== &dev_attr_end_lba
)
1685 ret
= sprintf(buf
, "%llu\n", q
->blk_trace
->end_lba
);
1688 mutex_unlock(&bdev
->bd_mutex
);
1695 static ssize_t
sysfs_blk_trace_attr_store(struct device
*dev
,
1696 struct device_attribute
*attr
,
1697 const char *buf
, size_t count
)
1699 struct block_device
*bdev
;
1700 struct request_queue
*q
;
1701 struct hd_struct
*p
;
1703 ssize_t ret
= -EINVAL
;
1708 if (attr
== &dev_attr_act_mask
) {
1709 if (sscanf(buf
, "%llx", &value
) != 1) {
1710 /* Assume it is a list of trace category names */
1711 ret
= blk_trace_str2mask(buf
);
1716 } else if (sscanf(buf
, "%llu", &value
) != 1)
1721 p
= dev_to_part(dev
);
1722 bdev
= bdget(part_devt(p
));
1726 q
= blk_trace_get_queue(bdev
);
1730 mutex_lock(&bdev
->bd_mutex
);
1732 if (attr
== &dev_attr_enable
) {
1734 ret
= blk_trace_setup_queue(q
, bdev
);
1736 ret
= blk_trace_remove_queue(q
);
1737 goto out_unlock_bdev
;
1741 if (q
->blk_trace
== NULL
)
1742 ret
= blk_trace_setup_queue(q
, bdev
);
1745 if (attr
== &dev_attr_act_mask
)
1746 q
->blk_trace
->act_mask
= value
;
1747 else if (attr
== &dev_attr_pid
)
1748 q
->blk_trace
->pid
= value
;
1749 else if (attr
== &dev_attr_start_lba
)
1750 q
->blk_trace
->start_lba
= value
;
1751 else if (attr
== &dev_attr_end_lba
)
1752 q
->blk_trace
->end_lba
= value
;
1756 mutex_unlock(&bdev
->bd_mutex
);
1760 return ret
? ret
: count
;
1763 int blk_trace_init_sysfs(struct device
*dev
)
1765 return sysfs_create_group(&dev
->kobj
, &blk_trace_attr_group
);
1768 void blk_trace_remove_sysfs(struct device
*dev
)
1770 sysfs_remove_group(&dev
->kobj
, &blk_trace_attr_group
);
1773 #endif /* CONFIG_BLK_DEV_IO_TRACE */
1775 #ifdef CONFIG_EVENT_TRACING
1777 void blk_dump_cmd(char *buf
, struct request
*rq
)
1780 int len
= rq
->cmd_len
;
1781 unsigned char *cmd
= rq
->cmd
;
1783 if (rq
->cmd_type
!= REQ_TYPE_BLOCK_PC
) {
1788 for (end
= len
- 1; end
>= 0; end
--)
1793 for (i
= 0; i
< len
; i
++) {
1794 buf
+= sprintf(buf
, "%s%02x", i
== 0 ? "" : " ", cmd
[i
]);
1795 if (i
== end
&& end
!= len
- 1) {
1796 sprintf(buf
, " ..");
1802 void blk_fill_rwbs(char *rwbs
, u32 rw
, int bytes
)
1811 else if (rw
& REQ_DISCARD
)
1820 if (rw
& REQ_RAHEAD
)
1826 if (rw
& REQ_SECURE
)
1832 #endif /* CONFIG_EVENT_TRACING */