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>
29 #include <linux/list.h>
31 #include "../../block/blk.h"
33 #include <trace/events/block.h>
35 #include "trace_output.h"
37 #ifdef CONFIG_BLK_DEV_IO_TRACE
39 static unsigned int blktrace_seq __read_mostly
= 1;
41 static struct trace_array
*blk_tr
;
42 static bool blk_tracer_enabled __read_mostly
;
44 static LIST_HEAD(running_trace_list
);
45 static __cacheline_aligned_in_smp
DEFINE_SPINLOCK(running_trace_lock
);
47 /* Select an alternative, minimalistic output than the original one */
48 #define TRACE_BLK_OPT_CLASSIC 0x1
50 static struct tracer_opt blk_tracer_opts
[] = {
51 /* Default disable the minimalistic output */
52 { TRACER_OPT(blk_classic
, TRACE_BLK_OPT_CLASSIC
) },
56 static struct tracer_flags blk_tracer_flags
= {
58 .opts
= blk_tracer_opts
,
61 /* Global reference count of probes */
62 static atomic_t blk_probes_ref
= ATOMIC_INIT(0);
64 static void blk_register_tracepoints(void);
65 static void blk_unregister_tracepoints(void);
68 * Send out a notify message.
70 static void trace_note(struct blk_trace
*bt
, pid_t pid
, int action
,
71 const void *data
, size_t len
)
73 struct blk_io_trace
*t
;
74 struct ring_buffer_event
*event
= NULL
;
75 struct ring_buffer
*buffer
= NULL
;
77 int cpu
= smp_processor_id();
78 bool blk_tracer
= blk_tracer_enabled
;
81 buffer
= blk_tr
->trace_buffer
.buffer
;
83 event
= trace_buffer_lock_reserve(buffer
, TRACE_BLK
,
88 t
= ring_buffer_event_data(event
);
95 t
= relay_reserve(bt
->rchan
, sizeof(*t
) + len
);
97 t
->magic
= BLK_IO_TRACE_MAGIC
| BLK_IO_TRACE_VERSION
;
98 t
->time
= ktime_to_ns(ktime_get());
105 memcpy((void *) t
+ sizeof(*t
), data
, len
);
108 trace_buffer_unlock_commit(blk_tr
, buffer
, event
, 0, pc
);
113 * Send out a notify for this process, if we haven't done so since a trace
116 static void trace_note_tsk(struct task_struct
*tsk
)
119 struct blk_trace
*bt
;
121 tsk
->btrace_seq
= blktrace_seq
;
122 spin_lock_irqsave(&running_trace_lock
, flags
);
123 list_for_each_entry(bt
, &running_trace_list
, running_list
) {
124 trace_note(bt
, tsk
->pid
, BLK_TN_PROCESS
, tsk
->comm
,
127 spin_unlock_irqrestore(&running_trace_lock
, flags
);
130 static void trace_note_time(struct blk_trace
*bt
)
132 struct timespec64 now
;
136 /* need to check user space to see if this breaks in y2038 or y2106 */
137 ktime_get_real_ts64(&now
);
138 words
[0] = (u32
)now
.tv_sec
;
139 words
[1] = now
.tv_nsec
;
141 local_irq_save(flags
);
142 trace_note(bt
, 0, BLK_TN_TIMESTAMP
, words
, sizeof(words
));
143 local_irq_restore(flags
);
146 void __trace_note_message(struct blk_trace
*bt
, const char *fmt
, ...)
153 if (unlikely(bt
->trace_state
!= Blktrace_running
&&
154 !blk_tracer_enabled
))
158 * If the BLK_TC_NOTIFY action mask isn't set, don't send any note
159 * message to the trace.
161 if (!(bt
->act_mask
& BLK_TC_NOTIFY
))
164 local_irq_save(flags
);
165 buf
= this_cpu_ptr(bt
->msg_data
);
167 n
= vscnprintf(buf
, BLK_TN_MAX_MSG
, fmt
, args
);
170 trace_note(bt
, 0, BLK_TN_MESSAGE
, buf
, n
);
171 local_irq_restore(flags
);
173 EXPORT_SYMBOL_GPL(__trace_note_message
);
175 static int act_log_check(struct blk_trace
*bt
, u32 what
, sector_t sector
,
178 if (((bt
->act_mask
<< BLK_TC_SHIFT
) & what
) == 0)
180 if (sector
&& (sector
< bt
->start_lba
|| sector
> bt
->end_lba
))
182 if (bt
->pid
&& pid
!= bt
->pid
)
189 * Data direction bit lookup
191 static const u32 ddir_act
[2] = { BLK_TC_ACT(BLK_TC_READ
),
192 BLK_TC_ACT(BLK_TC_WRITE
) };
194 #define BLK_TC_RAHEAD BLK_TC_AHEAD
195 #define BLK_TC_PREFLUSH BLK_TC_FLUSH
197 /* The ilog2() calls fall out because they're constant */
198 #define MASK_TC_BIT(rw, __name) ((rw & REQ_ ## __name) << \
199 (ilog2(BLK_TC_ ## __name) + BLK_TC_SHIFT - __REQ_ ## __name))
202 * The worker for the various blk_add_trace*() types. Fills out a
203 * blk_io_trace structure and places it in a per-cpu subbuffer.
205 static void __blk_add_trace(struct blk_trace
*bt
, sector_t sector
, int bytes
,
206 int op
, int op_flags
, u32 what
, int error
, int pdu_len
,
209 struct task_struct
*tsk
= current
;
210 struct ring_buffer_event
*event
= NULL
;
211 struct ring_buffer
*buffer
= NULL
;
212 struct blk_io_trace
*t
;
213 unsigned long flags
= 0;
214 unsigned long *sequence
;
217 bool blk_tracer
= blk_tracer_enabled
;
219 if (unlikely(bt
->trace_state
!= Blktrace_running
&& !blk_tracer
))
222 what
|= ddir_act
[op_is_write(op
) ? WRITE
: READ
];
223 what
|= MASK_TC_BIT(op_flags
, SYNC
);
224 what
|= MASK_TC_BIT(op_flags
, RAHEAD
);
225 what
|= MASK_TC_BIT(op_flags
, META
);
226 what
|= MASK_TC_BIT(op_flags
, PREFLUSH
);
227 what
|= MASK_TC_BIT(op_flags
, FUA
);
228 if (op
== REQ_OP_DISCARD
|| op
== REQ_OP_SECURE_ERASE
)
229 what
|= BLK_TC_ACT(BLK_TC_DISCARD
);
230 if (op
== REQ_OP_FLUSH
)
231 what
|= BLK_TC_ACT(BLK_TC_FLUSH
);
234 if (act_log_check(bt
, what
, sector
, pid
))
236 cpu
= raw_smp_processor_id();
239 tracing_record_cmdline(current
);
241 buffer
= blk_tr
->trace_buffer
.buffer
;
242 pc
= preempt_count();
243 event
= trace_buffer_lock_reserve(buffer
, TRACE_BLK
,
244 sizeof(*t
) + pdu_len
,
248 t
= ring_buffer_event_data(event
);
252 if (unlikely(tsk
->btrace_seq
!= blktrace_seq
))
256 * A word about the locking here - we disable interrupts to reserve
257 * some space in the relay per-cpu buffer, to prevent an irq
258 * from coming in and stepping on our toes.
260 local_irq_save(flags
);
261 t
= relay_reserve(bt
->rchan
, sizeof(*t
) + pdu_len
);
263 sequence
= per_cpu_ptr(bt
->sequence
, cpu
);
265 t
->magic
= BLK_IO_TRACE_MAGIC
| BLK_IO_TRACE_VERSION
;
266 t
->sequence
= ++(*sequence
);
267 t
->time
= ktime_to_ns(ktime_get());
270 * These two are not needed in ftrace as they are in the
271 * generic trace_entry, filled by tracing_generic_entry_update,
272 * but for the trace_event->bin() synthesizer benefit we do it
283 t
->pdu_len
= pdu_len
;
286 memcpy((void *) t
+ sizeof(*t
), pdu_data
, pdu_len
);
289 trace_buffer_unlock_commit(blk_tr
, buffer
, event
, 0, pc
);
294 local_irq_restore(flags
);
297 static void blk_trace_free(struct blk_trace
*bt
)
299 debugfs_remove(bt
->msg_file
);
300 debugfs_remove(bt
->dropped_file
);
301 relay_close(bt
->rchan
);
302 debugfs_remove(bt
->dir
);
303 free_percpu(bt
->sequence
);
304 free_percpu(bt
->msg_data
);
308 static void blk_trace_cleanup(struct blk_trace
*bt
)
311 if (atomic_dec_and_test(&blk_probes_ref
))
312 blk_unregister_tracepoints();
315 int blk_trace_remove(struct request_queue
*q
)
317 struct blk_trace
*bt
;
319 bt
= xchg(&q
->blk_trace
, NULL
);
323 if (bt
->trace_state
!= Blktrace_running
)
324 blk_trace_cleanup(bt
);
328 EXPORT_SYMBOL_GPL(blk_trace_remove
);
330 static ssize_t
blk_dropped_read(struct file
*filp
, char __user
*buffer
,
331 size_t count
, loff_t
*ppos
)
333 struct blk_trace
*bt
= filp
->private_data
;
336 snprintf(buf
, sizeof(buf
), "%u\n", atomic_read(&bt
->dropped
));
338 return simple_read_from_buffer(buffer
, count
, ppos
, buf
, strlen(buf
));
341 static const struct file_operations blk_dropped_fops
= {
342 .owner
= THIS_MODULE
,
344 .read
= blk_dropped_read
,
345 .llseek
= default_llseek
,
348 static ssize_t
blk_msg_write(struct file
*filp
, const char __user
*buffer
,
349 size_t count
, loff_t
*ppos
)
352 struct blk_trace
*bt
;
354 if (count
>= BLK_TN_MAX_MSG
)
357 msg
= memdup_user_nul(buffer
, count
);
361 bt
= filp
->private_data
;
362 __trace_note_message(bt
, "%s", msg
);
368 static const struct file_operations blk_msg_fops
= {
369 .owner
= THIS_MODULE
,
371 .write
= blk_msg_write
,
372 .llseek
= noop_llseek
,
376 * Keep track of how many times we encountered a full subbuffer, to aid
377 * the user space app in telling how many lost events there were.
379 static int blk_subbuf_start_callback(struct rchan_buf
*buf
, void *subbuf
,
380 void *prev_subbuf
, size_t prev_padding
)
382 struct blk_trace
*bt
;
384 if (!relay_buf_full(buf
))
387 bt
= buf
->chan
->private_data
;
388 atomic_inc(&bt
->dropped
);
392 static int blk_remove_buf_file_callback(struct dentry
*dentry
)
394 debugfs_remove(dentry
);
399 static struct dentry
*blk_create_buf_file_callback(const char *filename
,
400 struct dentry
*parent
,
402 struct rchan_buf
*buf
,
405 return debugfs_create_file(filename
, mode
, parent
, buf
,
406 &relay_file_operations
);
409 static struct rchan_callbacks blk_relay_callbacks
= {
410 .subbuf_start
= blk_subbuf_start_callback
,
411 .create_buf_file
= blk_create_buf_file_callback
,
412 .remove_buf_file
= blk_remove_buf_file_callback
,
415 static void blk_trace_setup_lba(struct blk_trace
*bt
,
416 struct block_device
*bdev
)
418 struct hd_struct
*part
= NULL
;
421 part
= bdev
->bd_part
;
424 bt
->start_lba
= part
->start_sect
;
425 bt
->end_lba
= part
->start_sect
+ part
->nr_sects
;
433 * Setup everything required to start tracing
435 static int do_blk_trace_setup(struct request_queue
*q
, char *name
, dev_t dev
,
436 struct block_device
*bdev
,
437 struct blk_user_trace_setup
*buts
)
439 struct blk_trace
*bt
= NULL
;
440 struct dentry
*dir
= NULL
;
443 if (!buts
->buf_size
|| !buts
->buf_nr
)
446 strncpy(buts
->name
, name
, BLKTRACE_BDEV_SIZE
);
447 buts
->name
[BLKTRACE_BDEV_SIZE
- 1] = '\0';
450 * some device names have larger paths - convert the slashes
451 * to underscores for this to work as expected
453 strreplace(buts
->name
, '/', '_');
455 bt
= kzalloc(sizeof(*bt
), GFP_KERNEL
);
460 bt
->sequence
= alloc_percpu(unsigned long);
464 bt
->msg_data
= __alloc_percpu(BLK_TN_MAX_MSG
, __alignof__(char));
470 if (!blk_debugfs_root
)
473 dir
= debugfs_lookup(buts
->name
, blk_debugfs_root
);
475 bt
->dir
= dir
= debugfs_create_dir(buts
->name
, blk_debugfs_root
);
480 atomic_set(&bt
->dropped
, 0);
481 INIT_LIST_HEAD(&bt
->running_list
);
484 bt
->dropped_file
= debugfs_create_file("dropped", 0444, dir
, bt
,
486 if (!bt
->dropped_file
)
489 bt
->msg_file
= debugfs_create_file("msg", 0222, dir
, bt
, &blk_msg_fops
);
493 bt
->rchan
= relay_open("trace", dir
, buts
->buf_size
,
494 buts
->buf_nr
, &blk_relay_callbacks
, bt
);
498 bt
->act_mask
= buts
->act_mask
;
500 bt
->act_mask
= (u16
) -1;
502 blk_trace_setup_lba(bt
, bdev
);
504 /* overwrite with user settings */
506 bt
->start_lba
= buts
->start_lba
;
508 bt
->end_lba
= buts
->end_lba
;
511 bt
->trace_state
= Blktrace_setup
;
514 if (cmpxchg(&q
->blk_trace
, NULL
, bt
))
517 if (atomic_inc_return(&blk_probes_ref
) == 1)
518 blk_register_tracepoints();
529 int blk_trace_setup(struct request_queue
*q
, char *name
, dev_t dev
,
530 struct block_device
*bdev
,
533 struct blk_user_trace_setup buts
;
536 ret
= copy_from_user(&buts
, arg
, sizeof(buts
));
540 ret
= do_blk_trace_setup(q
, name
, dev
, bdev
, &buts
);
544 if (copy_to_user(arg
, &buts
, sizeof(buts
))) {
550 EXPORT_SYMBOL_GPL(blk_trace_setup
);
552 #if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64)
553 static int compat_blk_trace_setup(struct request_queue
*q
, char *name
,
554 dev_t dev
, struct block_device
*bdev
,
557 struct blk_user_trace_setup buts
;
558 struct compat_blk_user_trace_setup cbuts
;
561 if (copy_from_user(&cbuts
, arg
, sizeof(cbuts
)))
564 buts
= (struct blk_user_trace_setup
) {
565 .act_mask
= cbuts
.act_mask
,
566 .buf_size
= cbuts
.buf_size
,
567 .buf_nr
= cbuts
.buf_nr
,
568 .start_lba
= cbuts
.start_lba
,
569 .end_lba
= cbuts
.end_lba
,
573 ret
= do_blk_trace_setup(q
, name
, dev
, bdev
, &buts
);
577 if (copy_to_user(arg
, &buts
.name
, ARRAY_SIZE(buts
.name
))) {
586 int blk_trace_startstop(struct request_queue
*q
, int start
)
589 struct blk_trace
*bt
= q
->blk_trace
;
595 * For starting a trace, we can transition from a setup or stopped
596 * trace. For stopping a trace, the state must be running
600 if (bt
->trace_state
== Blktrace_setup
||
601 bt
->trace_state
== Blktrace_stopped
) {
604 bt
->trace_state
= Blktrace_running
;
605 spin_lock_irq(&running_trace_lock
);
606 list_add(&bt
->running_list
, &running_trace_list
);
607 spin_unlock_irq(&running_trace_lock
);
613 if (bt
->trace_state
== Blktrace_running
) {
614 bt
->trace_state
= Blktrace_stopped
;
615 spin_lock_irq(&running_trace_lock
);
616 list_del_init(&bt
->running_list
);
617 spin_unlock_irq(&running_trace_lock
);
618 relay_flush(bt
->rchan
);
625 EXPORT_SYMBOL_GPL(blk_trace_startstop
);
628 * blk_trace_ioctl: - handle the ioctls associated with tracing
629 * @bdev: the block device
630 * @cmd: the ioctl cmd
631 * @arg: the argument data, if any
634 int blk_trace_ioctl(struct block_device
*bdev
, unsigned cmd
, char __user
*arg
)
636 struct request_queue
*q
;
638 char b
[BDEVNAME_SIZE
];
640 q
= bdev_get_queue(bdev
);
644 mutex_lock(&bdev
->bd_mutex
);
649 ret
= blk_trace_setup(q
, b
, bdev
->bd_dev
, bdev
, arg
);
651 #if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64)
652 case BLKTRACESETUP32
:
654 ret
= compat_blk_trace_setup(q
, b
, bdev
->bd_dev
, bdev
, arg
);
660 ret
= blk_trace_startstop(q
, start
);
662 case BLKTRACETEARDOWN
:
663 ret
= blk_trace_remove(q
);
670 mutex_unlock(&bdev
->bd_mutex
);
675 * blk_trace_shutdown: - stop and cleanup trace structures
676 * @q: the request queue associated with the device
679 void blk_trace_shutdown(struct request_queue
*q
)
682 blk_trace_startstop(q
, 0);
692 * blk_add_trace_rq - Add a trace for a request oriented action
693 * @q: queue the io is for
694 * @rq: the source request
695 * @nr_bytes: number of completed bytes
699 * Records an action against a request. Will log the bio offset + size.
702 static void blk_add_trace_rq(struct request_queue
*q
, struct request
*rq
,
703 unsigned int nr_bytes
, u32 what
)
705 struct blk_trace
*bt
= q
->blk_trace
;
710 if (blk_rq_is_passthrough(rq
))
711 what
|= BLK_TC_ACT(BLK_TC_PC
);
713 what
|= BLK_TC_ACT(BLK_TC_FS
);
715 __blk_add_trace(bt
, blk_rq_trace_sector(rq
), nr_bytes
, req_op(rq
),
716 rq
->cmd_flags
, what
, rq
->errors
, 0, NULL
);
719 static void blk_add_trace_rq_abort(void *ignore
,
720 struct request_queue
*q
, struct request
*rq
)
722 blk_add_trace_rq(q
, rq
, blk_rq_bytes(rq
), BLK_TA_ABORT
);
725 static void blk_add_trace_rq_insert(void *ignore
,
726 struct request_queue
*q
, struct request
*rq
)
728 blk_add_trace_rq(q
, rq
, blk_rq_bytes(rq
), BLK_TA_INSERT
);
731 static void blk_add_trace_rq_issue(void *ignore
,
732 struct request_queue
*q
, struct request
*rq
)
734 blk_add_trace_rq(q
, rq
, blk_rq_bytes(rq
), BLK_TA_ISSUE
);
737 static void blk_add_trace_rq_requeue(void *ignore
,
738 struct request_queue
*q
,
741 blk_add_trace_rq(q
, rq
, blk_rq_bytes(rq
), BLK_TA_REQUEUE
);
744 static void blk_add_trace_rq_complete(void *ignore
,
745 struct request_queue
*q
,
747 unsigned int nr_bytes
)
749 blk_add_trace_rq(q
, rq
, nr_bytes
, BLK_TA_COMPLETE
);
753 * blk_add_trace_bio - Add a trace for a bio oriented action
754 * @q: queue the io is for
755 * @bio: the source bio
757 * @error: error, if any
760 * Records an action against a bio. Will log the bio offset + size.
763 static void blk_add_trace_bio(struct request_queue
*q
, struct bio
*bio
,
766 struct blk_trace
*bt
= q
->blk_trace
;
771 __blk_add_trace(bt
, bio
->bi_iter
.bi_sector
, bio
->bi_iter
.bi_size
,
772 bio_op(bio
), bio
->bi_opf
, what
, error
, 0, NULL
);
775 static void blk_add_trace_bio_bounce(void *ignore
,
776 struct request_queue
*q
, struct bio
*bio
)
778 blk_add_trace_bio(q
, bio
, BLK_TA_BOUNCE
, 0);
781 static void blk_add_trace_bio_complete(void *ignore
,
782 struct request_queue
*q
, struct bio
*bio
,
785 blk_add_trace_bio(q
, bio
, BLK_TA_COMPLETE
, error
);
788 static void blk_add_trace_bio_backmerge(void *ignore
,
789 struct request_queue
*q
,
793 blk_add_trace_bio(q
, bio
, BLK_TA_BACKMERGE
, 0);
796 static void blk_add_trace_bio_frontmerge(void *ignore
,
797 struct request_queue
*q
,
801 blk_add_trace_bio(q
, bio
, BLK_TA_FRONTMERGE
, 0);
804 static void blk_add_trace_bio_queue(void *ignore
,
805 struct request_queue
*q
, struct bio
*bio
)
807 blk_add_trace_bio(q
, bio
, BLK_TA_QUEUE
, 0);
810 static void blk_add_trace_getrq(void *ignore
,
811 struct request_queue
*q
,
812 struct bio
*bio
, int rw
)
815 blk_add_trace_bio(q
, bio
, BLK_TA_GETRQ
, 0);
817 struct blk_trace
*bt
= q
->blk_trace
;
820 __blk_add_trace(bt
, 0, 0, rw
, 0, BLK_TA_GETRQ
, 0, 0,
826 static void blk_add_trace_sleeprq(void *ignore
,
827 struct request_queue
*q
,
828 struct bio
*bio
, int rw
)
831 blk_add_trace_bio(q
, bio
, BLK_TA_SLEEPRQ
, 0);
833 struct blk_trace
*bt
= q
->blk_trace
;
836 __blk_add_trace(bt
, 0, 0, rw
, 0, BLK_TA_SLEEPRQ
,
841 static void blk_add_trace_plug(void *ignore
, struct request_queue
*q
)
843 struct blk_trace
*bt
= q
->blk_trace
;
846 __blk_add_trace(bt
, 0, 0, 0, 0, BLK_TA_PLUG
, 0, 0, NULL
);
849 static void blk_add_trace_unplug(void *ignore
, struct request_queue
*q
,
850 unsigned int depth
, bool explicit)
852 struct blk_trace
*bt
= q
->blk_trace
;
855 __be64 rpdu
= cpu_to_be64(depth
);
859 what
= BLK_TA_UNPLUG_IO
;
861 what
= BLK_TA_UNPLUG_TIMER
;
863 __blk_add_trace(bt
, 0, 0, 0, 0, what
, 0, sizeof(rpdu
), &rpdu
);
867 static void blk_add_trace_split(void *ignore
,
868 struct request_queue
*q
, struct bio
*bio
,
871 struct blk_trace
*bt
= q
->blk_trace
;
874 __be64 rpdu
= cpu_to_be64(pdu
);
876 __blk_add_trace(bt
, bio
->bi_iter
.bi_sector
,
877 bio
->bi_iter
.bi_size
, bio_op(bio
), bio
->bi_opf
,
878 BLK_TA_SPLIT
, bio
->bi_error
, sizeof(rpdu
),
884 * blk_add_trace_bio_remap - Add a trace for a bio-remap operation
885 * @ignore: trace callback data parameter (not used)
886 * @q: queue the io is for
887 * @bio: the source bio
888 * @dev: target device
889 * @from: source sector
892 * Device mapper or raid target sometimes need to split a bio because
893 * it spans a stripe (or similar). Add a trace for that action.
896 static void blk_add_trace_bio_remap(void *ignore
,
897 struct request_queue
*q
, struct bio
*bio
,
898 dev_t dev
, sector_t from
)
900 struct blk_trace
*bt
= q
->blk_trace
;
901 struct blk_io_trace_remap r
;
906 r
.device_from
= cpu_to_be32(dev
);
907 r
.device_to
= cpu_to_be32(bio
->bi_bdev
->bd_dev
);
908 r
.sector_from
= cpu_to_be64(from
);
910 __blk_add_trace(bt
, bio
->bi_iter
.bi_sector
, bio
->bi_iter
.bi_size
,
911 bio_op(bio
), bio
->bi_opf
, BLK_TA_REMAP
, bio
->bi_error
,
916 * blk_add_trace_rq_remap - Add a trace for a request-remap operation
917 * @ignore: trace callback data parameter (not used)
918 * @q: queue the io is for
919 * @rq: the source request
920 * @dev: target device
921 * @from: source sector
924 * Device mapper remaps request to other devices.
925 * Add a trace for that action.
928 static void blk_add_trace_rq_remap(void *ignore
,
929 struct request_queue
*q
,
930 struct request
*rq
, dev_t dev
,
933 struct blk_trace
*bt
= q
->blk_trace
;
934 struct blk_io_trace_remap r
;
939 r
.device_from
= cpu_to_be32(dev
);
940 r
.device_to
= cpu_to_be32(disk_devt(rq
->rq_disk
));
941 r
.sector_from
= cpu_to_be64(from
);
943 __blk_add_trace(bt
, blk_rq_pos(rq
), blk_rq_bytes(rq
),
944 rq_data_dir(rq
), 0, BLK_TA_REMAP
, !!rq
->errors
,
949 * blk_add_driver_data - Add binary message with driver-specific data
950 * @q: queue the io is for
952 * @data: driver-specific data
953 * @len: length of driver-specific data
956 * Some drivers might want to write driver-specific data per request.
959 void blk_add_driver_data(struct request_queue
*q
,
961 void *data
, size_t len
)
963 struct blk_trace
*bt
= q
->blk_trace
;
968 __blk_add_trace(bt
, blk_rq_trace_sector(rq
), blk_rq_bytes(rq
), 0, 0,
969 BLK_TA_DRV_DATA
, rq
->errors
, len
, data
);
971 EXPORT_SYMBOL_GPL(blk_add_driver_data
);
973 static void blk_register_tracepoints(void)
977 ret
= register_trace_block_rq_abort(blk_add_trace_rq_abort
, NULL
);
979 ret
= register_trace_block_rq_insert(blk_add_trace_rq_insert
, NULL
);
981 ret
= register_trace_block_rq_issue(blk_add_trace_rq_issue
, NULL
);
983 ret
= register_trace_block_rq_requeue(blk_add_trace_rq_requeue
, NULL
);
985 ret
= register_trace_block_rq_complete(blk_add_trace_rq_complete
, NULL
);
987 ret
= register_trace_block_bio_bounce(blk_add_trace_bio_bounce
, NULL
);
989 ret
= register_trace_block_bio_complete(blk_add_trace_bio_complete
, NULL
);
991 ret
= register_trace_block_bio_backmerge(blk_add_trace_bio_backmerge
, NULL
);
993 ret
= register_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge
, NULL
);
995 ret
= register_trace_block_bio_queue(blk_add_trace_bio_queue
, NULL
);
997 ret
= register_trace_block_getrq(blk_add_trace_getrq
, NULL
);
999 ret
= register_trace_block_sleeprq(blk_add_trace_sleeprq
, NULL
);
1001 ret
= register_trace_block_plug(blk_add_trace_plug
, NULL
);
1003 ret
= register_trace_block_unplug(blk_add_trace_unplug
, NULL
);
1005 ret
= register_trace_block_split(blk_add_trace_split
, NULL
);
1007 ret
= register_trace_block_bio_remap(blk_add_trace_bio_remap
, NULL
);
1009 ret
= register_trace_block_rq_remap(blk_add_trace_rq_remap
, NULL
);
1013 static void blk_unregister_tracepoints(void)
1015 unregister_trace_block_rq_remap(blk_add_trace_rq_remap
, NULL
);
1016 unregister_trace_block_bio_remap(blk_add_trace_bio_remap
, NULL
);
1017 unregister_trace_block_split(blk_add_trace_split
, NULL
);
1018 unregister_trace_block_unplug(blk_add_trace_unplug
, NULL
);
1019 unregister_trace_block_plug(blk_add_trace_plug
, NULL
);
1020 unregister_trace_block_sleeprq(blk_add_trace_sleeprq
, NULL
);
1021 unregister_trace_block_getrq(blk_add_trace_getrq
, NULL
);
1022 unregister_trace_block_bio_queue(blk_add_trace_bio_queue
, NULL
);
1023 unregister_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge
, NULL
);
1024 unregister_trace_block_bio_backmerge(blk_add_trace_bio_backmerge
, NULL
);
1025 unregister_trace_block_bio_complete(blk_add_trace_bio_complete
, NULL
);
1026 unregister_trace_block_bio_bounce(blk_add_trace_bio_bounce
, NULL
);
1027 unregister_trace_block_rq_complete(blk_add_trace_rq_complete
, NULL
);
1028 unregister_trace_block_rq_requeue(blk_add_trace_rq_requeue
, NULL
);
1029 unregister_trace_block_rq_issue(blk_add_trace_rq_issue
, NULL
);
1030 unregister_trace_block_rq_insert(blk_add_trace_rq_insert
, NULL
);
1031 unregister_trace_block_rq_abort(blk_add_trace_rq_abort
, NULL
);
1033 tracepoint_synchronize_unregister();
1037 * struct blk_io_tracer formatting routines
1040 static void fill_rwbs(char *rwbs
, const struct blk_io_trace
*t
)
1043 int tc
= t
->action
>> BLK_TC_SHIFT
;
1045 if (t
->action
== BLK_TN_MESSAGE
) {
1050 if (tc
& BLK_TC_FLUSH
)
1053 if (tc
& BLK_TC_DISCARD
)
1055 else if (tc
& BLK_TC_WRITE
)
1062 if (tc
& BLK_TC_FUA
)
1064 if (tc
& BLK_TC_AHEAD
)
1066 if (tc
& BLK_TC_SYNC
)
1068 if (tc
& BLK_TC_META
)
1075 const struct blk_io_trace
*te_blk_io_trace(const struct trace_entry
*ent
)
1077 return (const struct blk_io_trace
*)ent
;
1080 static inline const void *pdu_start(const struct trace_entry
*ent
)
1082 return te_blk_io_trace(ent
) + 1;
1085 static inline u32
t_action(const struct trace_entry
*ent
)
1087 return te_blk_io_trace(ent
)->action
;
1090 static inline u32
t_bytes(const struct trace_entry
*ent
)
1092 return te_blk_io_trace(ent
)->bytes
;
1095 static inline u32
t_sec(const struct trace_entry
*ent
)
1097 return te_blk_io_trace(ent
)->bytes
>> 9;
1100 static inline unsigned long long t_sector(const struct trace_entry
*ent
)
1102 return te_blk_io_trace(ent
)->sector
;
1105 static inline __u16
t_error(const struct trace_entry
*ent
)
1107 return te_blk_io_trace(ent
)->error
;
1110 static __u64
get_pdu_int(const struct trace_entry
*ent
)
1112 const __u64
*val
= pdu_start(ent
);
1113 return be64_to_cpu(*val
);
1116 static void get_pdu_remap(const struct trace_entry
*ent
,
1117 struct blk_io_trace_remap
*r
)
1119 const struct blk_io_trace_remap
*__r
= pdu_start(ent
);
1120 __u64 sector_from
= __r
->sector_from
;
1122 r
->device_from
= be32_to_cpu(__r
->device_from
);
1123 r
->device_to
= be32_to_cpu(__r
->device_to
);
1124 r
->sector_from
= be64_to_cpu(sector_from
);
1127 typedef void (blk_log_action_t
) (struct trace_iterator
*iter
, const char *act
);
1129 static void blk_log_action_classic(struct trace_iterator
*iter
, const char *act
)
1131 char rwbs
[RWBS_LEN
];
1132 unsigned long long ts
= iter
->ts
;
1133 unsigned long nsec_rem
= do_div(ts
, NSEC_PER_SEC
);
1134 unsigned secs
= (unsigned long)ts
;
1135 const struct blk_io_trace
*t
= te_blk_io_trace(iter
->ent
);
1139 trace_seq_printf(&iter
->seq
,
1140 "%3d,%-3d %2d %5d.%09lu %5u %2s %3s ",
1141 MAJOR(t
->device
), MINOR(t
->device
), iter
->cpu
,
1142 secs
, nsec_rem
, iter
->ent
->pid
, act
, rwbs
);
1145 static void blk_log_action(struct trace_iterator
*iter
, const char *act
)
1147 char rwbs
[RWBS_LEN
];
1148 const struct blk_io_trace
*t
= te_blk_io_trace(iter
->ent
);
1151 trace_seq_printf(&iter
->seq
, "%3d,%-3d %2s %3s ",
1152 MAJOR(t
->device
), MINOR(t
->device
), act
, rwbs
);
1155 static void blk_log_dump_pdu(struct trace_seq
*s
, const struct trace_entry
*ent
)
1157 const unsigned char *pdu_buf
;
1161 pdu_buf
= pdu_start(ent
);
1162 pdu_len
= te_blk_io_trace(ent
)->pdu_len
;
1167 /* find the last zero that needs to be printed */
1168 for (end
= pdu_len
- 1; end
>= 0; end
--)
1173 trace_seq_putc(s
, '(');
1175 for (i
= 0; i
< pdu_len
; i
++) {
1177 trace_seq_printf(s
, "%s%02x",
1178 i
== 0 ? "" : " ", pdu_buf
[i
]);
1181 * stop when the rest is just zeroes and indicate so
1182 * with a ".." appended
1184 if (i
== end
&& end
!= pdu_len
- 1) {
1185 trace_seq_puts(s
, " ..) ");
1190 trace_seq_puts(s
, ") ");
1193 static void blk_log_generic(struct trace_seq
*s
, const struct trace_entry
*ent
)
1195 char cmd
[TASK_COMM_LEN
];
1197 trace_find_cmdline(ent
->pid
, cmd
);
1199 if (t_action(ent
) & BLK_TC_ACT(BLK_TC_PC
)) {
1200 trace_seq_printf(s
, "%u ", t_bytes(ent
));
1201 blk_log_dump_pdu(s
, ent
);
1202 trace_seq_printf(s
, "[%s]\n", cmd
);
1205 trace_seq_printf(s
, "%llu + %u [%s]\n",
1206 t_sector(ent
), t_sec(ent
), cmd
);
1208 trace_seq_printf(s
, "[%s]\n", cmd
);
1212 static void blk_log_with_error(struct trace_seq
*s
,
1213 const struct trace_entry
*ent
)
1215 if (t_action(ent
) & BLK_TC_ACT(BLK_TC_PC
)) {
1216 blk_log_dump_pdu(s
, ent
);
1217 trace_seq_printf(s
, "[%d]\n", t_error(ent
));
1220 trace_seq_printf(s
, "%llu + %u [%d]\n",
1222 t_sec(ent
), t_error(ent
));
1224 trace_seq_printf(s
, "%llu [%d]\n",
1225 t_sector(ent
), t_error(ent
));
1229 static void blk_log_remap(struct trace_seq
*s
, const struct trace_entry
*ent
)
1231 struct blk_io_trace_remap r
= { .device_from
= 0, };
1233 get_pdu_remap(ent
, &r
);
1234 trace_seq_printf(s
, "%llu + %u <- (%d,%d) %llu\n",
1235 t_sector(ent
), t_sec(ent
),
1236 MAJOR(r
.device_from
), MINOR(r
.device_from
),
1237 (unsigned long long)r
.sector_from
);
1240 static void blk_log_plug(struct trace_seq
*s
, const struct trace_entry
*ent
)
1242 char cmd
[TASK_COMM_LEN
];
1244 trace_find_cmdline(ent
->pid
, cmd
);
1246 trace_seq_printf(s
, "[%s]\n", cmd
);
1249 static void blk_log_unplug(struct trace_seq
*s
, const struct trace_entry
*ent
)
1251 char cmd
[TASK_COMM_LEN
];
1253 trace_find_cmdline(ent
->pid
, cmd
);
1255 trace_seq_printf(s
, "[%s] %llu\n", cmd
, get_pdu_int(ent
));
1258 static void blk_log_split(struct trace_seq
*s
, const struct trace_entry
*ent
)
1260 char cmd
[TASK_COMM_LEN
];
1262 trace_find_cmdline(ent
->pid
, cmd
);
1264 trace_seq_printf(s
, "%llu / %llu [%s]\n", t_sector(ent
),
1265 get_pdu_int(ent
), cmd
);
1268 static void blk_log_msg(struct trace_seq
*s
, const struct trace_entry
*ent
)
1270 const struct blk_io_trace
*t
= te_blk_io_trace(ent
);
1272 trace_seq_putmem(s
, t
+ 1, t
->pdu_len
);
1273 trace_seq_putc(s
, '\n');
1277 * struct tracer operations
1280 static void blk_tracer_print_header(struct seq_file
*m
)
1282 if (!(blk_tracer_flags
.val
& TRACE_BLK_OPT_CLASSIC
))
1284 seq_puts(m
, "# DEV CPU TIMESTAMP PID ACT FLG\n"
1288 static void blk_tracer_start(struct trace_array
*tr
)
1290 blk_tracer_enabled
= true;
1293 static int blk_tracer_init(struct trace_array
*tr
)
1296 blk_tracer_start(tr
);
1300 static void blk_tracer_stop(struct trace_array
*tr
)
1302 blk_tracer_enabled
= false;
1305 static void blk_tracer_reset(struct trace_array
*tr
)
1307 blk_tracer_stop(tr
);
1310 static const struct {
1312 void (*print
)(struct trace_seq
*s
, const struct trace_entry
*ent
);
1314 [__BLK_TA_QUEUE
] = {{ "Q", "queue" }, blk_log_generic
},
1315 [__BLK_TA_BACKMERGE
] = {{ "M", "backmerge" }, blk_log_generic
},
1316 [__BLK_TA_FRONTMERGE
] = {{ "F", "frontmerge" }, blk_log_generic
},
1317 [__BLK_TA_GETRQ
] = {{ "G", "getrq" }, blk_log_generic
},
1318 [__BLK_TA_SLEEPRQ
] = {{ "S", "sleeprq" }, blk_log_generic
},
1319 [__BLK_TA_REQUEUE
] = {{ "R", "requeue" }, blk_log_with_error
},
1320 [__BLK_TA_ISSUE
] = {{ "D", "issue" }, blk_log_generic
},
1321 [__BLK_TA_COMPLETE
] = {{ "C", "complete" }, blk_log_with_error
},
1322 [__BLK_TA_PLUG
] = {{ "P", "plug" }, blk_log_plug
},
1323 [__BLK_TA_UNPLUG_IO
] = {{ "U", "unplug_io" }, blk_log_unplug
},
1324 [__BLK_TA_UNPLUG_TIMER
] = {{ "UT", "unplug_timer" }, blk_log_unplug
},
1325 [__BLK_TA_INSERT
] = {{ "I", "insert" }, blk_log_generic
},
1326 [__BLK_TA_SPLIT
] = {{ "X", "split" }, blk_log_split
},
1327 [__BLK_TA_BOUNCE
] = {{ "B", "bounce" }, blk_log_generic
},
1328 [__BLK_TA_REMAP
] = {{ "A", "remap" }, blk_log_remap
},
1331 static enum print_line_t
print_one_line(struct trace_iterator
*iter
,
1334 struct trace_array
*tr
= iter
->tr
;
1335 struct trace_seq
*s
= &iter
->seq
;
1336 const struct blk_io_trace
*t
;
1339 blk_log_action_t
*log_action
;
1341 t
= te_blk_io_trace(iter
->ent
);
1342 what
= t
->action
& ((1 << BLK_TC_SHIFT
) - 1);
1343 long_act
= !!(tr
->trace_flags
& TRACE_ITER_VERBOSE
);
1344 log_action
= classic
? &blk_log_action_classic
: &blk_log_action
;
1346 if (t
->action
== BLK_TN_MESSAGE
) {
1347 log_action(iter
, long_act
? "message" : "m");
1348 blk_log_msg(s
, iter
->ent
);
1349 return trace_handle_return(s
);
1352 if (unlikely(what
== 0 || what
>= ARRAY_SIZE(what2act
)))
1353 trace_seq_printf(s
, "Unknown action %x\n", what
);
1355 log_action(iter
, what2act
[what
].act
[long_act
]);
1356 what2act
[what
].print(s
, iter
->ent
);
1359 return trace_handle_return(s
);
1362 static enum print_line_t
blk_trace_event_print(struct trace_iterator
*iter
,
1363 int flags
, struct trace_event
*event
)
1365 return print_one_line(iter
, false);
1368 static void blk_trace_synthesize_old_trace(struct trace_iterator
*iter
)
1370 struct trace_seq
*s
= &iter
->seq
;
1371 struct blk_io_trace
*t
= (struct blk_io_trace
*)iter
->ent
;
1372 const int offset
= offsetof(struct blk_io_trace
, sector
);
1373 struct blk_io_trace old
= {
1374 .magic
= BLK_IO_TRACE_MAGIC
| BLK_IO_TRACE_VERSION
,
1378 trace_seq_putmem(s
, &old
, offset
);
1379 trace_seq_putmem(s
, &t
->sector
,
1380 sizeof(old
) - offset
+ t
->pdu_len
);
1383 static enum print_line_t
1384 blk_trace_event_print_binary(struct trace_iterator
*iter
, int flags
,
1385 struct trace_event
*event
)
1387 blk_trace_synthesize_old_trace(iter
);
1389 return trace_handle_return(&iter
->seq
);
1392 static enum print_line_t
blk_tracer_print_line(struct trace_iterator
*iter
)
1394 if (!(blk_tracer_flags
.val
& TRACE_BLK_OPT_CLASSIC
))
1395 return TRACE_TYPE_UNHANDLED
;
1397 return print_one_line(iter
, true);
1401 blk_tracer_set_flag(struct trace_array
*tr
, u32 old_flags
, u32 bit
, int set
)
1403 /* don't output context-info for blk_classic output */
1404 if (bit
== TRACE_BLK_OPT_CLASSIC
) {
1406 tr
->trace_flags
&= ~TRACE_ITER_CONTEXT_INFO
;
1408 tr
->trace_flags
|= TRACE_ITER_CONTEXT_INFO
;
1413 static struct tracer blk_tracer __read_mostly
= {
1415 .init
= blk_tracer_init
,
1416 .reset
= blk_tracer_reset
,
1417 .start
= blk_tracer_start
,
1418 .stop
= blk_tracer_stop
,
1419 .print_header
= blk_tracer_print_header
,
1420 .print_line
= blk_tracer_print_line
,
1421 .flags
= &blk_tracer_flags
,
1422 .set_flag
= blk_tracer_set_flag
,
1425 static struct trace_event_functions trace_blk_event_funcs
= {
1426 .trace
= blk_trace_event_print
,
1427 .binary
= blk_trace_event_print_binary
,
1430 static struct trace_event trace_blk_event
= {
1432 .funcs
= &trace_blk_event_funcs
,
1435 static int __init
init_blk_tracer(void)
1437 if (!register_trace_event(&trace_blk_event
)) {
1438 pr_warn("Warning: could not register block events\n");
1442 if (register_tracer(&blk_tracer
) != 0) {
1443 pr_warn("Warning: could not register the block tracer\n");
1444 unregister_trace_event(&trace_blk_event
);
1451 device_initcall(init_blk_tracer
);
1453 static int blk_trace_remove_queue(struct request_queue
*q
)
1455 struct blk_trace
*bt
;
1457 bt
= xchg(&q
->blk_trace
, NULL
);
1461 if (atomic_dec_and_test(&blk_probes_ref
))
1462 blk_unregister_tracepoints();
1469 * Setup everything required to start tracing
1471 static int blk_trace_setup_queue(struct request_queue
*q
,
1472 struct block_device
*bdev
)
1474 struct blk_trace
*bt
= NULL
;
1477 bt
= kzalloc(sizeof(*bt
), GFP_KERNEL
);
1481 bt
->msg_data
= __alloc_percpu(BLK_TN_MAX_MSG
, __alignof__(char));
1485 bt
->dev
= bdev
->bd_dev
;
1486 bt
->act_mask
= (u16
)-1;
1488 blk_trace_setup_lba(bt
, bdev
);
1491 if (cmpxchg(&q
->blk_trace
, NULL
, bt
))
1494 if (atomic_inc_return(&blk_probes_ref
) == 1)
1495 blk_register_tracepoints();
1504 * sysfs interface to enable and configure tracing
1507 static ssize_t
sysfs_blk_trace_attr_show(struct device
*dev
,
1508 struct device_attribute
*attr
,
1510 static ssize_t
sysfs_blk_trace_attr_store(struct device
*dev
,
1511 struct device_attribute
*attr
,
1512 const char *buf
, size_t count
);
1513 #define BLK_TRACE_DEVICE_ATTR(_name) \
1514 DEVICE_ATTR(_name, S_IRUGO | S_IWUSR, \
1515 sysfs_blk_trace_attr_show, \
1516 sysfs_blk_trace_attr_store)
1518 static BLK_TRACE_DEVICE_ATTR(enable
);
1519 static BLK_TRACE_DEVICE_ATTR(act_mask
);
1520 static BLK_TRACE_DEVICE_ATTR(pid
);
1521 static BLK_TRACE_DEVICE_ATTR(start_lba
);
1522 static BLK_TRACE_DEVICE_ATTR(end_lba
);
1524 static struct attribute
*blk_trace_attrs
[] = {
1525 &dev_attr_enable
.attr
,
1526 &dev_attr_act_mask
.attr
,
1528 &dev_attr_start_lba
.attr
,
1529 &dev_attr_end_lba
.attr
,
1533 struct attribute_group blk_trace_attr_group
= {
1535 .attrs
= blk_trace_attrs
,
1538 static const struct {
1542 { BLK_TC_READ
, "read" },
1543 { BLK_TC_WRITE
, "write" },
1544 { BLK_TC_FLUSH
, "flush" },
1545 { BLK_TC_SYNC
, "sync" },
1546 { BLK_TC_QUEUE
, "queue" },
1547 { BLK_TC_REQUEUE
, "requeue" },
1548 { BLK_TC_ISSUE
, "issue" },
1549 { BLK_TC_COMPLETE
, "complete" },
1550 { BLK_TC_FS
, "fs" },
1551 { BLK_TC_PC
, "pc" },
1552 { BLK_TC_NOTIFY
, "notify" },
1553 { BLK_TC_AHEAD
, "ahead" },
1554 { BLK_TC_META
, "meta" },
1555 { BLK_TC_DISCARD
, "discard" },
1556 { BLK_TC_DRV_DATA
, "drv_data" },
1557 { BLK_TC_FUA
, "fua" },
1560 static int blk_trace_str2mask(const char *str
)
1564 char *buf
, *s
, *token
;
1566 buf
= kstrdup(str
, GFP_KERNEL
);
1572 token
= strsep(&s
, ",");
1579 for (i
= 0; i
< ARRAY_SIZE(mask_maps
); i
++) {
1580 if (strcasecmp(token
, mask_maps
[i
].str
) == 0) {
1581 mask
|= mask_maps
[i
].mask
;
1585 if (i
== ARRAY_SIZE(mask_maps
)) {
1595 static ssize_t
blk_trace_mask2str(char *buf
, int mask
)
1600 for (i
= 0; i
< ARRAY_SIZE(mask_maps
); i
++) {
1601 if (mask
& mask_maps
[i
].mask
) {
1602 p
+= sprintf(p
, "%s%s",
1603 (p
== buf
) ? "" : ",", mask_maps
[i
].str
);
1611 static struct request_queue
*blk_trace_get_queue(struct block_device
*bdev
)
1613 if (bdev
->bd_disk
== NULL
)
1616 return bdev_get_queue(bdev
);
1619 static ssize_t
sysfs_blk_trace_attr_show(struct device
*dev
,
1620 struct device_attribute
*attr
,
1623 struct hd_struct
*p
= dev_to_part(dev
);
1624 struct request_queue
*q
;
1625 struct block_device
*bdev
;
1626 ssize_t ret
= -ENXIO
;
1628 bdev
= bdget(part_devt(p
));
1632 q
= blk_trace_get_queue(bdev
);
1636 mutex_lock(&bdev
->bd_mutex
);
1638 if (attr
== &dev_attr_enable
) {
1639 ret
= sprintf(buf
, "%u\n", !!q
->blk_trace
);
1640 goto out_unlock_bdev
;
1643 if (q
->blk_trace
== NULL
)
1644 ret
= sprintf(buf
, "disabled\n");
1645 else if (attr
== &dev_attr_act_mask
)
1646 ret
= blk_trace_mask2str(buf
, q
->blk_trace
->act_mask
);
1647 else if (attr
== &dev_attr_pid
)
1648 ret
= sprintf(buf
, "%u\n", q
->blk_trace
->pid
);
1649 else if (attr
== &dev_attr_start_lba
)
1650 ret
= sprintf(buf
, "%llu\n", q
->blk_trace
->start_lba
);
1651 else if (attr
== &dev_attr_end_lba
)
1652 ret
= sprintf(buf
, "%llu\n", q
->blk_trace
->end_lba
);
1655 mutex_unlock(&bdev
->bd_mutex
);
1662 static ssize_t
sysfs_blk_trace_attr_store(struct device
*dev
,
1663 struct device_attribute
*attr
,
1664 const char *buf
, size_t count
)
1666 struct block_device
*bdev
;
1667 struct request_queue
*q
;
1668 struct hd_struct
*p
;
1670 ssize_t ret
= -EINVAL
;
1675 if (attr
== &dev_attr_act_mask
) {
1676 if (sscanf(buf
, "%llx", &value
) != 1) {
1677 /* Assume it is a list of trace category names */
1678 ret
= blk_trace_str2mask(buf
);
1683 } else if (sscanf(buf
, "%llu", &value
) != 1)
1688 p
= dev_to_part(dev
);
1689 bdev
= bdget(part_devt(p
));
1693 q
= blk_trace_get_queue(bdev
);
1697 mutex_lock(&bdev
->bd_mutex
);
1699 if (attr
== &dev_attr_enable
) {
1701 ret
= blk_trace_setup_queue(q
, bdev
);
1703 ret
= blk_trace_remove_queue(q
);
1704 goto out_unlock_bdev
;
1708 if (q
->blk_trace
== NULL
)
1709 ret
= blk_trace_setup_queue(q
, bdev
);
1712 if (attr
== &dev_attr_act_mask
)
1713 q
->blk_trace
->act_mask
= value
;
1714 else if (attr
== &dev_attr_pid
)
1715 q
->blk_trace
->pid
= value
;
1716 else if (attr
== &dev_attr_start_lba
)
1717 q
->blk_trace
->start_lba
= value
;
1718 else if (attr
== &dev_attr_end_lba
)
1719 q
->blk_trace
->end_lba
= value
;
1723 mutex_unlock(&bdev
->bd_mutex
);
1727 return ret
? ret
: count
;
1730 int blk_trace_init_sysfs(struct device
*dev
)
1732 return sysfs_create_group(&dev
->kobj
, &blk_trace_attr_group
);
1735 void blk_trace_remove_sysfs(struct device
*dev
)
1737 sysfs_remove_group(&dev
->kobj
, &blk_trace_attr_group
);
1740 #endif /* CONFIG_BLK_DEV_IO_TRACE */
1742 #ifdef CONFIG_EVENT_TRACING
1744 void blk_fill_rwbs(char *rwbs
, unsigned int op
, int bytes
)
1748 if (op
& REQ_PREFLUSH
)
1751 switch (op
& REQ_OP_MASK
) {
1753 case REQ_OP_WRITE_SAME
:
1756 case REQ_OP_DISCARD
:
1759 case REQ_OP_SECURE_ERASE
:
1775 if (op
& REQ_RAHEAD
)
1784 EXPORT_SYMBOL_GPL(blk_fill_rwbs
);
1786 #endif /* CONFIG_EVENT_TRACING */