summaryrefslogtreecommitdiffstats
path: root/kernel/trace/trace.h
blob: 630c5a24b2b255bf7cd35ef1524e25508835679f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
/* SPDX-License-Identifier: GPL-2.0 */

#ifndef _LINUX_KERNEL_TRACE_H
#define _LINUX_KERNEL_TRACE_H

#include <linux/fs.h>
#include <linux/atomic.h>
#include <linux/sched.h>
#include <linux/clocksource.h>
#include <linux/ring_buffer.h>
#include <linux/mmiotrace.h>
#include <linux/tracepoint.h>
#include <linux/ftrace.h>
#include <linux/hw_breakpoint.h>
#include <linux/trace_seq.h>
#include <linux/trace_events.h>
#include <linux/compiler.h>
#include <linux/trace_seq.h>
#include <linux/glob.h>

#ifdef CONFIG_FTRACE_SYSCALLS
#include <asm/unistd.h>		/* For NR_SYSCALLS	     */
#include <asm/syscall.h>	/* some archs define it here */
#endif

enum trace_type {
	__TRACE_FIRST_TYPE = 0,

	TRACE_FN,
	TRACE_CTX,
	TRACE_WAKE,
	TRACE_STACK,
	TRACE_PRINT,
	TRACE_BPRINT,
	TRACE_MMIO_RW,
	TRACE_MMIO_MAP,
	TRACE_BRANCH,
	TRACE_GRAPH_RET,
	TRACE_GRAPH_ENT,
	TRACE_USER_STACK,
	TRACE_BLK,
	TRACE_BPUTS,
	TRACE_HWLAT,
	TRACE_RAW_DATA,

	__TRACE_LAST_TYPE,
};


#undef __field
#define __field(type, item)		type	item;

#undef __field_struct
#define __field_struct(type, item)	__field(type, item)

#undef __field_desc
#define __field_desc(type, container, item)

#undef __array
#define __array(type, item, size)	type	item[size];

#undef __array_desc
#define __array_desc(type, container, item, size)

#undef __dynamic_array
#define __dynamic_array(type, item)	type	item[];

#undef F_STRUCT
#define F_STRUCT(args...)		args

#undef FTRACE_ENTRY
#define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter)	\
	struct struct_name {						\
		struct trace_entry	ent;				\
		tstruct							\
	}

#undef FTRACE_ENTRY_DUP
#define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk, filter)

#undef FTRACE_ENTRY_REG
#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print,	\
			 filter, regfn) \
	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
		     filter)

#undef FTRACE_ENTRY_PACKED
#define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print,	\
			    filter)					\
	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
		     filter) __packed

#include "trace_entries.h"

/*
 * syscalls are special, and need special handling, this is why
 * they are not included in trace_entries.h
 */
struct syscall_trace_enter {
	struct trace_entry	ent;
	int			nr;
	unsigned long		args[];
};

struct syscall_trace_exit {
	struct trace_entry	ent;
	int			nr;
	long			ret;
};

struct kprobe_trace_entry_head {
	struct trace_entry	ent;
	unsigned long		ip;
};

struct kretprobe_trace_entry_head {
	struct trace_entry	ent;
	unsigned long		func;
	unsigned long		ret_ip;
};

/*
 * trace_flag_type is an enumeration that holds different
 * states when a trace occurs. These are:
 *  IRQS_OFF		- interrupts were disabled
 *  IRQS_NOSUPPORT	- arch does not support irqs_disabled_flags
 *  NEED_RESCHED	- reschedule is requested
 *  HARDIRQ		- inside an interrupt handler
 *  SOFTIRQ		- inside a softirq handler
 */
enum trace_flag_type {
	TRACE_FLAG_IRQS_OFF		= 0x01,
	TRACE_FLAG_IRQS_NOSUPPORT	= 0x02,
	TRACE_FLAG_NEED_RESCHED		= 0x04,
	TRACE_FLAG_HARDIRQ		= 0x08,
	TRACE_FLAG_SOFTIRQ		= 0x10,
	TRACE_FLAG_PREEMPT_RESCHED	= 0x20,
	TRACE_FLAG_NMI			= 0x40,
};

#define TRACE_BUF_SIZE		1024

struct trace_array;

/*
 * The CPU trace array - it consists of thousands of trace entries
 * plus some other descriptor data: (for example which task started
 * the trace, etc.)
 */
struct trace_array_cpu {
	atomic_t		disabled;
	void			*buffer_page;	/* ring buffer spare */

	unsigned long		entries;
	unsigned long		saved_latency;
	unsigned long		critical_start;
	unsigned long		critical_end;
	unsigned long		critical_sequence;
	unsigned long		nice;
	unsigned long		policy;
	unsigned long		rt_priority;
	unsigned long		skipped_entries;
	u64			preempt_timestamp;
	pid_t			pid;
	kuid_t			uid;
	char			comm[TASK_COMM_LEN];

	bool			ignore_pid;
#ifdef CONFIG_FUNCTION_TRACER
	bool			ftrace_ignore_pid;
#endif
};

struct tracer;
struct trace_option_dentry;

struct trace_buffer {
	struct trace_array		*tr;
	struct ring_buffer		*buffer;
	struct trace_array_cpu __percpu	*data;
	u64				time_start;
	int				cpu;
};

#define TRACE_FLAGS_MAX_SIZE		32

struct trace_options {
	struct tracer			*tracer;
	struct trace_option_dentry	*topts;
};

struct trace_pid_list {
	int				pid_max;
	unsigned long			*pids;
};

/*
 * The trace array - an array of per-CPU trace arrays. This is the
 * highest level data structure that individual tracers deal with.
 * They have on/off state as well:
 */
struct trace_array {
	struct list_head	list;
	char			*name;
	struct trace_buffer	trace_buffer;
#ifdef CONFIG_TRACER_MAX_TRACE
	/*
	 * The max_buffer is used to snapshot the trace when a maximum
	 * latency is reached, or when the user initiates a snapshot.
	 * Some tracers will use this to store a maximum trace while
	 * it continues examining live traces.
	 *
	 * The buffers for the max_buffer are set up the same as the trace_buffer
	 * When a snapshot is taken, the buffer of the max_buffer is swapped
	 * with the buffer of the trace_buffer and the buffers are reset for
	 * the trace_buffer so the tracing can continue.
	 */
	struct trace_buffer	max_buffer;
	bool			allocated_snapshot;
#endif
#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)
	unsigned long		max_latency;
#endif
	struct trace_pid_list	__rcu *filtered_pids;
	/*
	 * max_lock is used to protect the swapping of buffers
	 * when taking a max snapshot. The buffers themselves are
	 * protected by per_cpu spinlocks. But the action of the swap
	 * needs its own lock.
	 *
	 * This is defined as a arch_spinlock_t in order to help
	 * with performance when lockdep debugging is enabled.
	 *
	 * It is also used in other places outside the update_max_tr
	 * so it needs to be defined outside of the
	 * CONFIG_TRACER_MAX_TRACE.
	 */
	arch_spinlock_t		max_lock;
	int			buffer_disabled;
#ifdef CONFIG_FTRACE_SYSCALLS
	int			sys_refcount_enter;
	int			sys_refcount_exit;
	struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
	struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
#endif
	int			stop_count;
	int			clock_id;
	int			nr_topts;
	bool			clear_trace;
	struct tracer		*current_trace;
	unsigned int		trace_flags;
	unsigned char		trace_flags_index[TRACE_FLAGS_MAX_SIZE];
	unsigned int		flags;
	raw_spinlock_t		start_lock;
	struct dentry		*dir;
	struct dentry		*options;
	struct dentry		*percpu_dir;
	struct dentry		*event_dir;
	struct trace_options	*topts;
	struct list_head	systems;
	struct list_head	events;
	struct trace_event_file *trace_marker_file;
	cpumask_var_t		tracing_cpumask; /* only trace on set CPUs */
	int			ref;
#ifdef CONFIG_FUNCTION_TRACER
	struct ftrace_ops	*ops;
	struct trace_pid_list	__rcu *function_pids;
#ifdef CONFIG_DYNAMIC_FTRACE
	/* All of these are protected by the ftrace_lock */
	struct list_head	func_probes;
	struct list_head	mod_trace;
	struct list_head	mod_notrace;
#endif
	/* function tracing enabled */
	int			function_enabled;
#endif
	int			time_stamp_abs_ref;
	struct list_head	hist_vars;
};

enum {
	TRACE_ARRAY_FL_GLOBAL	= (1 << 0)
};

extern struct list_head ftrace_trace_arrays;

extern struct mutex trace_types_lock;

extern int trace_array_get(struct trace_array *tr);
extern void trace_array_put(struct trace_array *tr);

extern int tracing_set_time_stamp_abs(struct trace_array *tr, bool abs);
extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);

extern bool trace_clock_in_ns(struct trace_array *tr);

/*
 * The global tracer (top) should be the first trace array added,
 * but we check the flag anyway.
 */
static inline struct trace_array *top_trace_array(void)
{
	struct trace_array *tr;

	if (list_empty(&ftrace_trace_arrays))
		return NULL;

	tr = list_entry(ftrace_trace_arrays.prev,
			typeof(*tr), list);
	WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
	return tr;
}

#define FTRACE_CMP_TYPE(var, type) \
	__builtin_types_compatible_p(typeof(var), type *)

#undef IF_ASSIGN
#define IF_ASSIGN(var, entry, etype, id)		\
	if (FTRACE_CMP_TYPE(var, etype)) {		\
		var = (typeof(var))(entry);		\
		WARN_ON(id && (entry)->type != id);	\
		break;					\
	}

/* Will cause compile errors if type is not found. */
extern void __ftrace_bad_type(void);

/*
 * The trace_assign_type is a verifier that the entry type is
 * the same as the type being assigned. To add new types simply
 * add a line with the following format:
 *
 * IF_ASSIGN(var, ent, type, id);
 *
 *  Where "type" is the trace type that includes the trace_entry
 *  as the "ent" item. And "id" is the trace identifier that is
 *  used in the trace_type enum.
 *
 *  If the type can have more than one id, then use zero.
 */
#define trace_assign_type(var, ent)					\
	do {								\
		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
		IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);	\
		IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT);	\
		IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
			  TRACE_MMIO_RW);				\
		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
			  TRACE_MMIO_MAP);				\
		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
			  TRACE_GRAPH_ENT);		\
		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
			  TRACE_GRAPH_RET);		\
		__ftrace_bad_type();					\
	} while (0)

/*
 * An option specific to a tracer. This is a boolean value.
 * The bit is the bit index that sets its value on the
 * flags value in struct tracer_flags.
 */
struct tracer_opt {
	const char	*name; /* Will appear on the trace_options file */
	u32		bit; /* Mask assigned in val field in tracer_flags */
};

/*
 * The set of specific options for a tracer. Your tracer
 * have to set the initial value of the flags val.
 */
struct tracer_flags {
	u32			val;
	struct tracer_opt	*opts;
	struct tracer		*trace;
};

/* Makes more easy to define a tracer opt */
#define TRACER_OPT(s, b)	.name = #s, .bit = b


struct trace_option_dentry {
	struct tracer_opt		*opt;
	struct tracer_flags		*flags;
	struct trace_array		*tr;
	struct dentry			*entry;
};

/**
 * struct tracer - a specific tracer and its callbacks to interact with tracefs
 * @name: the name chosen to select it on the available_tracers file
 * @init: called when one switches to this tracer (echo name > current_tracer)
 * @reset: called when one switches to another tracer
 * @start: called when tracing is unpaused (echo 1 > tracing_on)
 * @stop: called when tracing is paused (echo 0 > tracing_on)
 * @update_thresh: called when tracing_thresh is updated
 * @open: called when the trace file is opened
 * @pipe_open: called when the trace_pipe file is opened
 * @close: called when the trace file is released
 * @pipe_close: called when the trace_pipe file is released
 * @read: override the default read callback on trace_pipe
 * @splice_read: override the default splice_read callback on trace_pipe
 * @selftest: selftest to run on boot (see trace_selftest.c)
 * @print_headers: override the first lines that describe your columns
 * @print_line: callback that prints a trace
 * @set_flag: signals one of your private flags changed (trace_options file)
 * @flags: your private flags
 */
struct tracer {
	const char		*name;
	int			(*init)(struct trace_array *tr);
	void			(*reset)(struct trace_array *tr);
	void			(*start)(struct trace_array *tr);
	void			(*stop)(struct trace_array *tr);
	int			(*update_thresh)(struct trace_array *tr);
	void			(*open)(struct trace_iterator *iter);
	void			(*pipe_open)(struct trace_iterator *iter);
	void			(*close)(struct trace_iterator *iter);
	void			(*pipe_close)(struct trace_iterator *iter);
	ssize_t			(*read)(struct trace_iterator *iter,
					struct file *filp, char __user *ubuf,
					size_t cnt, loff_t *ppos);
	ssize_t			(*splice_read)(struct trace_iterator *iter,
					       struct file *filp,
					       loff_t *ppos,
					       struct pipe_inode_info *pipe,
					       size_t len,
					       unsigned int flags);
#ifdef CONFIG_FTRACE_STARTUP_TEST
	int			(*selftest)(struct tracer *trace,
					    struct trace_array *tr);
#endif
	void			(*print_header)(struct seq_file *m);
	enum print_line_t	(*print_line)(struct trace_iterator *iter);
	/* If you handled the flag setting, return 0 */
	int			(*set_flag)(struct trace_array *tr,
					    u32 old_flags, u32 bit, int set);
	/* Return 0 if OK with change, else return non-zero */
	int			(*flag_changed)(struct trace_array *tr,
						u32 mask, int set);
	struct tracer		*next;
	struct tracer_flags	*flags;
	int			enabled;
	int			ref;
	bool			print_max;
	bool			allow_instances;
#ifdef CONFIG_TRACER_MAX_TRACE
	bool			use_max_tr;
#endif
	/* True if tracer cannot be enabled in kernel param */
	bool			noboot;
};


/* Only current can touch trace_recursion */

/*
 * For function tracing recursion:
 *  The order of these bits are important.
 *
 *  When function tracing occurs, the following steps are made:
 *   If arch does not support a ftrace feature:
 *    call internal function (uses INTERNAL bits) which calls...
 *   If callback is registered to the "global" list, the list
 *    function is called and recursion checks the GLOBAL bits.
 *    then this function calls...
 *   The function callback, which can use the FTRACE bits to
 *    check for recursion.
 *
 * Now if the arch does not suppport a feature, and it calls
 * the global list function which calls the ftrace callback
 * all three of these steps will do a recursion protection.
 * There's no reason to do one if the previous caller already
 * did. The recursion that we are protecting against will
 * go through the same steps again.
 *
 * To prevent the multiple recursion checks, if a recursion
 * bit is set that is higher than the MAX bit of the current
 * check, then we know that the check was made by the previous
 * caller, and we can skip the current check.
 */
enum {
	TRACE_BUFFER_BIT,
	TRACE_BUFFER_NMI_BIT,
	TRACE_BUFFER_IRQ_BIT,
	TRACE_BUFFER_SIRQ_BIT,

	/* Start of function recursion bits */
	TRACE_FTRACE_BIT,
	TRACE_FTRACE_NMI_BIT,
	TRACE_FTRACE_IRQ_BIT,
	TRACE_FTRACE_SIRQ_BIT,

	/* INTERNAL_BITs must be greater than FTRACE_BITs */
	TRACE_INTERNAL_BIT,
	TRACE_INTERNAL_NMI_BIT,
	TRACE_INTERNAL_IRQ_BIT,
	TRACE_INTERNAL_SIRQ_BIT,

	TRACE_BRANCH_BIT,
/*
 * Abuse of the trace_recursion.
 * As we need a way to maintain state if we are tracing the function
 * graph in irq because we want to trace a particular function that
 * was called in irq context but we have irq tracing off. Since this
 * can only be modified by current, we can reuse trace_recursion.
 */
	TRACE_IRQ_BIT,
};

#define trace_recursion_set(bit)	do { (current)->trace_recursion |= (1<<(bit)); } while (0)
#define trace_recursion_clear(bit)	do { (current)->trace_recursion &= ~(1<<(bit)); } while (0)
#define trace_recursion_test(bit)	((current)->trace_recursion & (1<<(bit)))

#define TRACE_CONTEXT_BITS	4

#define TRACE_FTRACE_START	TRACE_FTRACE_BIT
#define TRACE_FTRACE_MAX	((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1)

#define TRACE_LIST_START	TRACE_INTERNAL_BIT
#define TRACE_LIST_MAX		((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1)

#define TRACE_CONTEXT_MASK	TRACE_LIST_MAX

static __always_inline int trace_get_context_bit(void)
{
	int bit;

	if (in_interrupt()) {
		if (in_nmi())
			bit = 0;

		else if (in_irq())
			bit = 1;
		else
			bit = 2;
	} else
		bit = 3;

	return bit;
}

static __always_inline int trace_test_and_set_recursion(int start, int max)
{
	unsigned int val = current->trace_recursion;
	int bit;

	/* A previous recursion check was made */
	if ((val & TRACE_CONTEXT_MASK) > max)
		return 0;

	bit = trace_get_context_bit() + start;
	if (unlikely(val & (1 << bit)))
		return -1;

	val |= 1 << bit;
	current->trace_recursion = val;
	barrier();

	return bit;
}

static __always_inline void trace_clear_recursion(int bit)
{
	unsigned int val = current->trace_recursion;

	if (!bit)
		return;

	bit = 1 << bit;
	val &= ~bit;

	barrier();
	current->trace_recursion = val;
}

static inline struct ring_buffer_iter *
trace_buffer_iter(struct trace_iterator *iter, int cpu)
{
	if (iter->buffer_iter && iter->buffer_iter[cpu])
		return iter->buffer_iter[cpu];
	return NULL;
}

int tracer_init(struct tracer *t, struct trace_array *tr);
int tracing_is_enabled(void);
void tracing_reset(struct trace_buffer *buf, int cpu);
void tracing_reset_online_cpus(struct trace_buffer *buf);
void tracing_reset_current(int cpu);
void tracing_reset_all_online_cpus(void);
int tracing_open_generic(struct inode *inode, struct file *filp);
bool tracing_is_disabled(void);
int tracer_tracing_is_on(struct trace_array *tr);
void tracer_tracing_on(struct trace_array *tr);
void tracer_tracing_off(struct trace_array *tr);
struct dentry *trace_create_file(const char *name,
				 umode_t mode,
				 struct dentry *parent,
				 void *data,
				 const struct file_operations *fops);

struct dentry *tracing_init_dentry(void);

struct ring_buffer_event;

struct ring_buffer_event *
trace_buffer_lock_reserve(struct ring_buffer *buffer,
			  int type,
			  unsigned long len,
			  unsigned long flags,
			  int pc);

struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
						struct trace_array_cpu *data);

struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
					  int *ent_cpu, u64 *ent_ts);

void trace_buffer_unlock_commit_nostack(struct ring_buffer *buffer,
					struct ring_buffer_event *event);

int trace_empty(struct trace_iterator *iter);

void *trace_find_next_entry_inc(struct trace_iterator *iter);

void trace_init_global_iter(struct trace_iterator *iter);

void tracing_iter_reset(struct trace_iterator *iter, int cpu);

void trace_function(struct trace_array *tr,
		    unsigned long ip,
		    unsigned long parent_ip,
		    unsigned long flags, int pc);
void trace_graph_function(struct trace_array *tr,
		    unsigned long ip,
		    unsigned long parent_ip,
		    unsigned long flags, int pc);
void trace_latency_header(struct seq_file *m);
void trace_default_header(struct seq_file *m);
void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
int trace_empty(struct trace_iterator *iter);

void trace_graph_return(struct ftrace_graph_ret *trace);
int trace_graph_entry(struct ftrace_graph_ent *trace);
void set_graph_array(struct trace_array *tr);

void tracing_start_cmdline_record(void);
void tracing_stop_cmdline_record(void);
void tracing_start_tgid_record(void);
void tracing_stop_tgid_record(void);

int register_tracer(struct tracer *type);
int is_tracing_stopped(void);

loff_t tracing_lseek(struct file *file, loff_t offset, int whence);

extern cpumask_var_t __read_mostly tracing_buffer_mask;

#define for_each_tracing_cpu(cpu)	\
	for_each_cpu(cpu, tracing_buffer_mask)

extern unsigned long nsecs_to_usecs(unsigned long nsecs);

extern unsigned long tracing_thresh;

/* PID filtering */

extern int pid_max;

bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
			     pid_t search_pid);
bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
			    struct task_struct *task);
void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
				  struct task_struct *self,
				  struct task_struct *task);
void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
int trace_pid_show(struct seq_file *m, void *v);
void trace_free_pid_list(struct trace_pid_list *pid_list);
int trace_pid_write(struct trace_pid_list *filtered_pids,
		    struct trace_pid_list **new_pid_list,
		    const char __user *ubuf, size_t cnt);

#ifdef CONFIG_TRACER_MAX_TRACE
void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
void update_max_tr_single(struct trace_array *tr,
			  struct task_struct *tsk, int cpu);
#endif /* CONFIG_TRACER_MAX_TRACE */

#ifdef CONFIG_STACKTRACE
void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
			    int pc);

void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
		   int pc);
#else
static inline void ftrace_trace_userstack(struct ring_buffer *buffer,
					  unsigned long flags, int pc)
{
}

static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
				 int skip, int pc)
{
}
#endif /* CONFIG_STACKTRACE */

extern u64 ftrace_now(int cpu);

extern void trace_find_cmdline(int pid, char comm[]);
extern int trace_find_tgid(int pid);
extern void trace_event_follow_fork(struct trace_array *tr, bool enable);

#ifdef CONFIG_DYNAMIC_FTRACE
extern unsigned long ftrace_update_tot_cnt;
void ftrace_init_trace_array(struct trace_array *tr);
#else
static inline void ftrace_init_trace_array(struct trace_array *tr) { }
#endif
#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
extern int DYN_FTRACE_TEST_NAME(void);
#define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
extern int DYN_FTRACE_TEST_NAME2(void);

extern bool ring_buffer_expanded;
extern bool tracing_selftest_disabled;

#ifdef CONFIG_FTRACE_STARTUP_TEST
extern int trace_selftest_startup_function(struct tracer *trace,
					   struct trace_array *tr);
extern int trace_selftest_startup_function_graph(struct tracer *trace,
						 struct trace_array *tr);
extern int trace_selftest_startup_irqsoff(struct tracer *trace,
					  struct trace_array *tr);
extern int trace_selftest_startup_preemptoff(struct tracer *trace,
					     struct trace_array *tr);
extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
						 struct trace_array *tr);
extern int trace_selftest_startup_wakeup(struct tracer *trace,
					 struct trace_array *tr);
extern int trace_selftest_startup_nop(struct tracer *trace,
					 struct trace_array *tr);
extern int trace_selftest_startup_branch(struct tracer *trace,
					 struct trace_array *tr);
/*
 * Tracer data references selftest functions that only occur
 * on boot up. These can be __init functions. Thus, when selftests
 * are enabled, then the tracers need to reference __init functions.
 */
#define __tracer_data		__refdata
#else
/* Tracers are seldom changed. Optimize when selftests are disabled. */
#define __tracer_data		__read_mostly
#endif /* CONFIG_FTRACE_STARTUP_TEST */

extern void *head_page(struct trace_array_cpu *data);
extern unsigned long long ns2usecs(u64 nsec);
extern int
trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
extern int
trace_vprintk(unsigned long ip, const char *fmt, va_list args);
extern int
trace_array_vprintk(struct trace_array *tr,
		    unsigned long ip, const char *fmt, va_list args);
int trace_array_printk(struct trace_array *tr,
		       unsigned long ip, const char *fmt, ...);
int trace_array_printk_buf(struct ring_buffer *buffer,
			   unsigned long ip, const char *fmt, ...);
void trace_printk_seq(struct trace_seq *s);
enum print_line_t print_trace_line(struct trace_iterator *iter);

extern char trace_find_mark(unsigned long long duration);

struct ftrace_hash;

struct ftrace_mod_load {
	struct list_head	list;
	char			*func;
	char			*module;
	int			 enable;
};

enum {
	FTRACE_HASH_FL_MOD	= (1 << 0),
};

struct ftrace_hash {
	unsigned long		size_bits;
	struct hlist_head	*buckets;
	unsigned long		count;
	unsigned long		flags;
	struct rcu_head		rcu;
};

struct ftrace_func_entry *
ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);

static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
{
	return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
}

/* Standard output formatting function used for function return traces */
#ifdef CONFIG_FUNCTION_GRAPH_TRACER

/* Flag options */
#define TRACE_GRAPH_PRINT_OVERRUN       0x1
#define TRACE_GRAPH_PRINT_CPU           0x2
#define TRACE_GRAPH_PRINT_OVERHEAD      0x4
#define TRACE_GRAPH_PRINT_PROC          0x8
#define TRACE_GRAPH_PRINT_DURATION      0x10
#define TRACE_GRAPH_PRINT_ABS_TIME      0x20
#define TRACE_GRAPH_PRINT_IRQS          0x40
#define TRACE_GRAPH_PRINT_TAIL          0x80
#define TRACE_GRAPH_SLEEP_TIME		0x100
#define TRACE_GRAPH_GRAPH_TIME		0x200
#define TRACE_GRAPH_PRINT_FILL_SHIFT	28
#define TRACE_GRAPH_PRINT_FILL_MASK	(0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)

extern void ftrace_graph_sleep_time_control(bool enable);
extern void ftrace_graph_graph_time_control(bool enable);

extern enum print_line_t
print_graph_function_flags(struct trace_iterator *iter, u32 flags);
extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
extern void
trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
extern void graph_trace_open(struct trace_iterator *iter);
extern void graph_trace_close(struct trace_iterator *iter);
extern int __trace_graph_entry(struct trace_array *tr,
			       struct ftrace_graph_ent *trace,
			       unsigned long flags, int pc);
extern void __trace_graph_return(struct trace_array *tr,
				 struct ftrace_graph_ret *trace,
				 unsigned long flags, int pc);

#ifdef CONFIG_DYNAMIC_FTRACE
extern struct ftrace_hash *ftrace_graph_hash;
extern struct ftrace_hash *ftrace_graph_notrace_hash;

static inline int ftrace_graph_addr(unsigned long addr)
{
	int ret = 0;

	preempt_disable_notrace();

	if (ftrace_hash_empty(ftrace_graph_hash)) {
		ret = 1;
		goto out;
	}

	if (ftrace_lookup_ip(ftrace_graph_hash, addr)) {
		/*
		 * If no irqs are to be traced, but a set_graph_function
		 * is set, and called by an interrupt handler, we still
		 * want to trace it.
		 */
		if (in_irq())
			trace_recursion_set(TRACE_IRQ_BIT);
		else
			trace_recursion_clear(TRACE_IRQ_BIT);
		ret = 1;
	}

out:
	preempt_enable_notrace();
	return ret;
}

static inline int ftrace_graph_notrace_addr(unsigned long addr)
{
	int ret = 0;

	preempt_disable_notrace();

	if (ftrace_lookup_ip(ftrace_graph_notrace_hash, addr))
		ret = 1;

	preempt_enable_notrace();
	return ret;
}
#else
static inline int ftrace_graph_addr(unsigned long addr)
{
	return 1;
}

static inline int ftrace_graph_notrace_addr(unsigned long addr)
{
	return 0;
}
#endif /* CONFIG_DYNAMIC_FTRACE */

extern unsigned int fgraph_max_depth;

static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
{
	/* trace it when it is-nested-in or is a function enabled. */
	return !(trace->depth || ftrace_graph_addr(trace->func)) ||
		(trace->depth < 0) ||
		(fgraph_max_depth && trace->depth >= fgraph_max_depth);
}

#else /* CONFIG_FUNCTION_GRAPH_TRACER */
static inline enum print_line_t
print_graph_function_flags(struct trace_iterator *iter, u32 flags)
{
	return TRACE_TYPE_UNHANDLED;
}
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */

extern struct list_head ftrace_pids;

#ifdef CONFIG_FUNCTION_TRACER
struct ftrace_func_command {
	struct list_head	list;
	char			*name;
	int			(*func)(struct trace_array *tr,
					struct ftrace_hash *hash,
					char *func, char *cmd,
					char *params, int enable);
};
extern bool ftrace_filter_param __initdata;
static inline int ftrace_trace_task(struct trace_array *tr)
{
	return !this_cpu_read(tr->trace_buffer.data->ftrace_ignore_pid);
}
extern int ftrace_is_dead(void);
int ftrace_create_function_files(struct trace_array *tr,
				 struct dentry *parent);
void ftrace_destroy_function_files(struct trace_array *tr);
void ftrace_init_global_array_ops(struct trace_array *tr);
void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
void ftrace_reset_array_ops(struct trace_array *tr);
int using_ftrace_ops_list_func(void);
void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
void ftrace_init_tracefs_toplevel(struct trace_array *tr,
				  struct dentry *d_tracer);
void ftrace_clear_pids(struct trace_array *tr);
int init_function_trace(void);
void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
#else
static inline int ftrace_trace_task(struct trace_array *tr)
{
	return 1;
}
static inline int ftrace_is_dead(void) { return 0; }
static inline int
ftrace_create_function_files(struct trace_array *tr,
			     struct dentry *parent)
{
	return 0;
}
static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
static inline __init void
ftrace_init_global_array_ops(struct trace_array *tr) { }
static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
static inline void ftrace_clear_pids(struct trace_array *tr) { }
static inline int init_function_trace(void) { return 0; }
static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
/* ftace_func_t type is not defined, use macro instead of static inline */
#define ftrace_init_array_ops(tr, func) do { } while (0)
#endif /* CONFIG_FUNCTION_TRACER */

#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)

struct ftrace_probe_ops {
	void			(*func)(unsigned long ip,
					unsigned long parent_ip,
					struct trace_array *tr,
					struct ftrace_probe_ops *ops,
					void *data);
	int			(*init)(struct ftrace_probe_ops *ops,
					struct trace_array *tr,
					unsigned long ip, void *init_data,
					void **data);
	void			(*free)(struct ftrace_probe_ops *ops,
					struct trace_array *tr,
					unsigned long ip, void *data);
	int			(*print)(struct seq_file *m,
					 unsigned long ip,
					 struct ftrace_probe_ops *ops,
					 void *data);
};

struct ftrace_func_mapper;
typedef int (*ftrace_mapper_func)(void *data);

struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
					   unsigned long ip);
int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
			       unsigned long ip, void *data);
void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
				   unsigned long ip);
void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
			     ftrace_mapper_func free_func);

extern int
register_ftrace_function_probe(char *glob, struct trace_array *tr,
			       struct ftrace_probe_ops *ops, void *data);
extern int
unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
				      struct ftrace_probe_ops *ops);
extern void clear_ftrace_function_probes(struct trace_array *tr);

int register_ftrace_command(struct ftrace_func_command *cmd);
int unregister_ftrace_command(struct ftrace_func_command *cmd);

void ftrace_create_filter_files(struct ftrace_ops *ops,
				struct dentry *parent);
void ftrace_destroy_filter_files(struct ftrace_ops *ops);
#else
struct ftrace_func_command;

static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
{
	return -EINVAL;
}
static inline __init int unregister_ftrace_command(char *cmd_name)
{
	return -EINVAL;
}
static inline void clear_ftrace_function_probes(struct trace_array *tr)
{
}

/*
 * The ops parameter passed in is usually undefined.
 * This must be a macro.
 */
#define ftrace_create_filter_files(ops, parent) do { } while (0)
#define ftrace_destroy_filter_files(ops) do { } while (0)
#endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */

bool ftrace_event_is_function(struct trace_event_call *call);

/*
 * struct trace_parser - servers for reading the user input separated by spaces
 * @cont: set if the input is not complete - no final space char was found
 * @buffer: holds the parsed user input
 * @idx: user input length
 * @size: buffer size
 */
struct trace_parser {
	bool		cont;
	char		*buffer;
	unsigned	idx;
	unsigned	size;
};

static inline bool trace_parser_loaded(struct trace_parser *parser)
{
	return (parser->idx != 0);
}

static inline bool trace_parser_cont(struct trace_parser *parser)
{
	return parser->cont;
}

static inline void trace_parser_clear(struct trace_parser *parser)
{
	parser->cont = false;
	parser->idx = 0;
}

extern int trace_parser_get_init(struct trace_parser *parser, int size);
extern void trace_parser_put(struct trace_parser *parser);
extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
	size_t cnt, loff_t *ppos);

/*
 * Only create function graph options if function graph is configured.
 */
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
# define FGRAPH_FLAGS						\
		C(DISPLAY_GRAPH,	"display-graph"),
#else
# define FGRAPH_FLAGS
#endif

#ifdef CONFIG_BRANCH_TRACER
# define BRANCH_FLAGS					\
		C(BRANCH,		"branch"),
#else
# define BRANCH_FLAGS
#endif

#ifdef CONFIG_FUNCTION_TRACER
# define FUNCTION_FLAGS						\
		C(FUNCTION,		"function-trace"),	\
		C(FUNC_FORK,		"function-fork"),
# define FUNCTION_DEFAULT_FLAGS		TRACE_ITER_FUNCTION
#else
# define FUNCTION_FLAGS
# define FUNCTION_DEFAULT_FLAGS		0UL
# define TRACE_ITER_FUNC_FORK		0UL
#endif

#ifdef CONFIG_STACKTRACE
# define STACK_FLAGS				\
		C(STACKTRACE,		"stacktrace"),
#else
# define STACK_FLAGS
#endif

/*
 * trace_iterator_flags is an enumeration that defines bit
 * positions into trace_flags that controls the output.
 *
 * NOTE: These bits must match the trace_options array in
 *       trace.c (this macro guarantees it).
 */
#define TRACE_FLAGS						\
		C(PRINT_PARENT,		"print-parent"),	\
		C(SYM_OFFSET,		"sym-offset"),		\
		C(SYM_ADDR,		"sym-addr"),		\
		C(VERBOSE,		"verbose"),		\
		C(RAW,			"raw"),			\
		C(HEX,			"hex"),			\
		C(BIN,			"bin"),			\
		C(BLOCK,		"block"),		\
		C(PRINTK,		"trace_printk"),	\
		C(ANNOTATE,		"annotate"),		\
		C(USERSTACKTRACE,	"userstacktrace"),	\
		C(SYM_USEROBJ,		"sym-userobj"),		\
		C(PRINTK_MSGONLY,	"printk-msg-only"),	\
		C(CONTEXT_INFO,		"context-info"),   /* Print pid/cpu/time */ \
		C(LATENCY_FMT,		"latency-format"),	\
		C(RECORD_CMD,		"record-cmd"),		\
		C(RECORD_TGID,		"record-tgid"),		\
		C(OVERWRITE,		"overwrite"),		\
		C(STOP_ON_FREE,		"disable_on_free"),	\
		C(IRQ_INFO,		"irq-info"),		\
		C(MARKERS,		"markers"),		\
		C(EVENT_FORK,		"event-fork"),		\
		FUNCTION_FLAGS					\
		FGRAPH_FLAGS					\
		STACK_FLAGS					\
		BRANCH_FLAGS

/*
 * By defining C, we can make TRACE_FLAGS a list of bit names
 * that will define the bits for the flag masks.
 */
#undef C
#define C(a, b) TRACE_ITER_##a##_BIT

enum trace_iterator_bits {
	TRACE_FLAGS
	/* Make sure we don't go more than we have bits for */
	TRACE_ITER_LAST_BIT
};

/*
 * By redefining C, we can make TRACE_FLAGS a list of masks that
 * use the bits as defined above.
 */
#undef C
#define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)

enum trace_iterator_flags { TRACE_FLAGS };

/*
 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
 * control the output of kernel symbols.
 */
#define TRACE_ITER_SYM_MASK \
	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)

extern struct tracer nop_trace;

#ifdef CONFIG_BRANCH_TRACER
extern int enable_branch_tracing(struct trace_array *tr);
extern void disable_branch_tracing(void);
static inline int trace_branch_enable(struct trace_array *tr)
{
	if (tr->trace_flags & TRACE_ITER_BRANCH)
		return enable_branch_tracing(tr);
	return 0;
}
static inline void trace_branch_disable(void)
{
	/* due to races, always disable */
	disable_branch_tracing();
}
#else
static inline int trace_branch_enable(struct trace_array *tr)
{
	return 0;
}
static inline void trace_branch_disable(void)
{
}
#endif /* CONFIG_BRANCH_TRACER */

/* set ring buffers to default size if not already done so */
int tracing_update_buffers(void);

struct ftrace_event_field {
	struct list_head	link;
	const char		*name;
	const char		*type;
	int			filter_type;
	int			offset;
	int			size;
	int			is_signed;
};

struct prog_entry;

struct event_filter {
	struct prog_entry __rcu	*prog;
	char			*filter_string;
};

struct event_subsystem {
	struct list_head	list;
	const char		*name;
	struct event_filter	*filter;
	int			ref_count;
};

struct trace_subsystem_dir {
	struct list_head		list;
	struct event_subsystem		*subsystem;
	struct trace_array		*tr;
	struct dentry			*entry;
	int				ref_count;
	int				nr_events;
};

extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
				     struct ring_buffer *buffer,
				     struct ring_buffer_event *event);

void trace_buffer_unlock_commit_regs(struct trace_array *tr,
				     struct ring_buffer *buffer,
				     struct ring_buffer_event *event,
				     unsigned long flags, int pc,
				     struct pt_regs *regs);

static inline void trace_buffer_unlock_commit(struct trace_array *tr,
					      struct ring_buffer *buffer,
					      struct ring_buffer_event *event,
					      unsigned long flags, int pc)
{
	trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL);
}

DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
DECLARE_PER_CPU(int, trace_buffered_event_cnt);
void trace_buffered_event_disable(void);
void trace_buffered_event_enable(void);

static inline void
__trace_event_discard_commit(struct ring_buffer *buffer,
			     struct ring_buffer_event *event)
{
	if (this_cpu_read(trace_buffered_event) == event) {
		/* Simply release the temp buffer */
		this_cpu_dec(trace_buffered_event_cnt);
		return;
	}
	ring_buffer_discard_commit(buffer, event);
}

/*
 * Helper function for event_trigger_unlock_commit{_regs}().
 * If there are event triggers attached to this event that requires
 * filtering against its fields, then they wil be called as the
 * entry already holds the field information of the current event.
 *
 * It also checks if the event should be discarded or not.
 * It is to be discarded if the event is soft disabled and the
 * event was only recorded to process triggers, or if the event
 * filter is active and this event did not match the filters.
 *
 * Returns true if the event is discarded, false otherwise.
 */
static inline bool
__event_trigger_test_discard(struct trace_event_file *file,
			     struct ring_buffer *buffer,
			     struct ring_buffer_event *event,
			     void *entry,
			     enum event_trigger_type *tt)
{
	unsigned long eflags = file->flags;

	if (eflags & EVENT_FILE_FL_TRIGGER_COND)
		*tt = event_triggers_call(file, entry, event);

	if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) ||
	    (unlikely(file->flags & EVENT_FILE_FL_FILTERED) &&
	     !filter_match_preds(file->filter, entry))) {
		__trace_event_discard_commit(buffer, event);
		return true;
	}

	return false;
}

/**
 * event_trigger_unlock_commit - handle triggers and finish event commit
 * @file: The file pointer assoctiated to the event
 * @buffer: The ring buffer that the event is being written to
 * @event: The event meta data in the ring buffer
 * @entry: The event itself
 * @irq_flags: The state of the interrupts at the start of the event
 * @pc: The state of the preempt count at the start of the event.
 *
 * This is a helper function to handle triggers that require data
 * from the event itself. It also tests the event against filters and
 * if the event is soft disabled and should be discarded.
 */
static inline void
event_trigger_unlock_commit(struct trace_event_file *file,
			    struct ring_buffer *buffer,
			    struct ring_buffer_event *event,
			    void *entry, unsigned long irq_flags, int pc)
{
	enum event_trigger_type tt = ETT_NONE;

	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
		trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc);

	if (tt)
		event_triggers_post_call(file, tt);
}

/**
 * event_trigger_unlock_commit_regs - handle triggers and finish event commit
 * @file: The file pointer assoctiated to the event
 * @buffer: The ring buffer that the event is being written to
 * @event: The event meta data in the ring buffer
 * @entry: The event itself
 * @irq_flags: The state of the interrupts at the start of the event
 * @pc: The state of the preempt count at the start of the event.
 *
 * This is a helper function to handle triggers that require data
 * from the event itself. It also tests the event against filters and
 * if the event is soft disabled and should be discarded.
 *
 * Same as event_trigger_unlock_commit() but calls
 * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit().
 */
static inline void
event_trigger_unlock_commit_regs(struct trace_event_file *file,
				 struct ring_buffer *buffer,
				 struct ring_buffer_event *event,
				 void *entry, unsigned long irq_flags, int pc,
				 struct pt_regs *regs)
{
	enum event_trigger_type tt = ETT_NONE;

	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
		trace_buffer_unlock_commit_regs(file->tr, buffer, event,
						irq_flags, pc, regs);

	if (tt)
		event_triggers_post_call(file, tt);
}

#define FILTER_PRED_INVALID	((unsigned short)-1)
#define FILTER_PRED_IS_RIGHT	(1 << 15)
#define FILTER_PRED_FOLD	(1 << 15)

/*
 * The max preds is the size of unsigned short with
 * two flags at the MSBs. One bit is used for both the IS_RIGHT
 * and FOLD flags. The other is reserved.
 *
 * 2^14 preds is way more than enough.
 */
#define MAX_FILTER_PRED		16384

struct filter_pred;
struct regex;

typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);

typedef int (*regex_match_func)(char *str, struct regex *r, int len);

enum regex_type {
	MATCH_FULL = 0,
	MATCH_FRONT_ONLY,
	MATCH_MIDDLE_ONLY,
	MATCH_END_ONLY,
	MATCH_GLOB,
};

struct regex {
	char			pattern[MAX_FILTER_STR_VAL];
	int			len;
	int			field_len;
	regex_match_func	match;
};

struct filter_pred {
	filter_pred_fn_t 	fn;
	u64 			val;
	struct regex		regex;
	unsigned short		*ops;
	struct ftrace_event_field *field;
	int 			offset;
	int			not;
	int 			op;
};

static inline bool is_string_field(struct ftrace_event_field *field)
{
	return field->filter_type == FILTER_DYN_STRING ||
	       field->filter_type == FILTER_STATIC_STRING ||
	       field->filter_type == FILTER_PTR_STRING ||
	       field->filter_type == FILTER_COMM;
}

static inline bool is_function_field(struct ftrace_event_field *field)
{
	return field->filter_type == FILTER_TRACE_FN;
}

extern enum regex_type
filter_parse_regex(char *buff, int len, char **search, int *not);
extern void print_event_filter(struct trace_event_file *file,
			       struct trace_seq *s);
extern int apply_event_filter(struct trace_event_file *file,
			      char *filter_string);
extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
					char *filter_string);
extern void print_subsystem_event_filter(struct event_subsystem *system,
					 struct trace_seq *s);
extern int filter_assign_type(const char *type);
extern int create_event_filter(struct trace_event_call *call,
			       char *filter_str, bool set_str,
			       struct event_filter **filterp);
extern void free_event_filter(struct event_filter *filter);

struct ftrace_event_field *
trace_find_event_field(struct trace_event_call *call, char *name);

extern void trace_event_enable_cmd_record(bool enable);
extern void trace_event_enable_tgid_record(bool enable);

extern int event_trace_init(void);
extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
extern int event_trace_del_tracer(struct trace_array *tr);

extern struct trace_event_file *__find_event_file(struct trace_array *tr,
						  const char *system,
						  const char *event);
extern struct trace_event_file *find_event_file(struct trace_array *tr,
						const char *system,
						const char *event);

static inline void *event_file_data(struct file *filp)
{
	return READ_ONCE(file_inode(filp)->i_private);
}

extern struct mutex event_mutex;
extern struct list_head ftrace_events;

extern const struct file_operations event_trigger_fops;
extern const struct file_operations event_hist_fops;

#ifdef CONFIG_HIST_TRIGGERS
extern int register_trigger_hist_cmd(void);
extern int register_trigger_hist_enable_disable_cmds(void);
#else
static inline int register_trigger_hist_cmd(void) { return 0; }
static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
#endif

extern int register_trigger_cmds(void);
extern void clear_event_triggers(struct trace_array *tr);

struct event_trigger_data {
	unsigned long			count;
	int				ref;
	struct event_trigger_ops	*ops;
	struct event_command		*cmd_ops;
	struct event_filter __rcu	*filter;
	char				*filter_str;
	void				*private_data;
	bool				paused;
	bool				paused_tmp;
	struct list_head		list;
	char				*name;
	struct list_head		named_list;
	struct event_trigger_data	*named_data;
};

/* Avoid typos */
#define ENABLE_EVENT_STR	"enable_event"
#define DISABLE_EVENT_STR	"disable_event"
#define ENABLE_HIST_STR		"enable_hist"
#define DISABLE_HIST_STR	"disable_hist"

struct enable_trigger_data {
	struct trace_event_file		*file;
	bool				enable;
	bool				hist;
};

extern int event_enable_trigger_print(struct seq_file *m,
				      struct event_trigger_ops *ops,
				      struct event_trigger_data *data);
extern void event_enable_trigger_free(struct event_trigger_ops *ops,
				      struct event_trigger_data *data);
extern int event_enable_trigger_func(struct event_command *cmd_ops,
				     struct trace_event_file *file,
				     char *glob, char *cmd, char *param);
extern int event_enable_register_trigger(char *glob,
					 struct event_trigger_ops *ops,
					 struct event_trigger_data *data,
					 struct trace_event_file *file);
extern void event_enable_unregister_trigger(char *glob,
					    struct event_trigger_ops *ops,
					    struct event_trigger_data *test,
					    struct trace_event_file *file);
extern void trigger_data_free(struct event_trigger_data *data);
extern int event_trigger_init(struct event_trigger_ops *ops,
			      struct event_trigger_data *data);
extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
					      int trigger_enable);
extern void update_cond_flag(struct trace_event_file *file);
extern void unregister_trigger(char *glob, struct event_trigger_ops *ops,
			       struct event_trigger_data *test,
			       struct trace_event_file *file);
extern int set_trigger_filter(char *filter_str,
			      struct event_trigger_data *trigger_data,
			      struct trace_event_file *file);
extern struct event_trigger_data *find_named_trigger(const char *name);
extern bool is_named_trigger(struct event_trigger_data *test);
extern int save_named_trigger(const char *name,
			      struct event_trigger_data *data);
extern void del_named_trigger(struct event_trigger_data *data);
extern void pause_named_trigger(struct event_trigger_data *data);
extern void unpause_named_trigger(struct event_trigger_data *data);
extern void set_named_trigger_data(struct event_trigger_data *data,
				   struct event_trigger_data *named_data);
extern struct event_trigger_data *
get_named_trigger_data(struct event_trigger_data *data);
extern int register_event_command(struct event_command *cmd);
extern int unregister_event_command(struct event_command *cmd);
extern int register_trigger_hist_enable_disable_cmds(void);

/**
 * struct event_trigger_ops - callbacks for trace event triggers
 *
 * The methods in this structure provide per-event trigger hooks for
 * various trigger operations.
 *
 * All the methods below, except for @init() and @free(), must be
 * implemented.
 *
 * @func: The trigger 'probe' function called when the triggering
 *	event occurs.  The data passed into this callback is the data
 *	that was supplied to the event_command @reg() function that
 *	registered the trigger (see struct event_command) along with
 *	the trace record, rec.
 *
 * @init: An optional initialization function called for the trigger
 *	when the trigger is registered (via the event_command reg()
 *	function).  This can be used to perform per-trigger
 *	initialization such as incrementing a per-trigger reference
 *	count, for instance.  This is usually implemented by the
 *	generic utility function @event_trigger_init() (see
 *	trace_event_triggers.c).
 *
 * @free: An optional de-initialization function called for the
 *	trigger when the trigger is unregistered (via the
 *	event_command @reg() function).  This can be used to perform
 *	per-trigger de-initialization such as decrementing a
 *	per-trigger reference count and freeing corresponding trigger
 *	data, for instance.  This is usually implemented by the
 *	generic utility function @event_trigger_free() (see
 *	trace_event_triggers.c).
 *
 * @print: The callback function invoked to have the trigger print
 *	itself.  This is usually implemented by a wrapper function
 *	that calls the generic utility function @event_trigger_print()
 *	(see trace_event_triggers.c).
 */
struct event_trigger_ops {
	void			(*func)(struct event_trigger_data *data,
					void *rec,
					struct ring_buffer_event *rbe);
	int			(*init)(struct event_trigger_ops *ops,
					struct event_trigger_data *data);
	void			(*free)(struct event_trigger_ops *ops,
					struct event_trigger_data *data);
	int			(*print)(struct seq_file *m,
					 struct event_trigger_ops *ops,
					 struct event_trigger_data *data);
};

/**
 * struct event_command - callbacks and data members for event commands
 *
 * Event commands are invoked by users by writing the command name
 * into the 'trigger' file associated with a trace event.  The
 * parameters associated with a specific invocation of an event
 * command are used to create an event trigger instance, which is
 * added to the list of trigger instances associated with that trace
 * event.  When the event is hit, the set of triggers associated with
 * that event is invoked.
 *
 * The data members in this structure provide per-event command data
 * for various event commands.
 *
 * All the data members below, except for @post_trigger, must be set
 * for each event command.
 *
 * @name: The unique name that identifies the event command.  This is
 *	the name used when setting triggers via trigger files.
 *
 * @trigger_type: A unique id that identifies the event command
 *	'type'.  This value has two purposes, the first to ensure that
 *	only one trigger of the same type can be set at a given time
 *	for a particular event e.g. it doesn't make sense to have both
 *	a traceon and traceoff trigger attached to a single event at
 *	the same time, so traceon and traceoff have the same type
 *	though they have different names.  The @trigger_type value is
 *	also used as a bit value for deferring the actual trigger
 *	action until after the current event is finished.  Some
 *	commands need to do this if they themselves log to the trace
 *	buffer (see the @post_trigger() member below).  @trigger_type
 *	values are defined by adding new values to the trigger_type
 *	enum in include/linux/trace_events.h.
 *
 * @flags: See the enum event_command_flags below.
 *
 * All the methods below, except for @set_filter() and @unreg_all(),
 * must be implemented.
 *
 * @func: The callback function responsible for parsing and
 *	registering the trigger written to the 'trigger' file by the
 *	user.  It allocates the trigger instance and registers it with
 *	the appropriate trace event.  It makes use of the other
 *	event_command callback functions to orchestrate this, and is
 *	usually implemented by the generic utility function
 *	@event_trigger_callback() (see trace_event_triggers.c).
 *
 * @reg: Adds the trigger to the list of triggers associated with the
 *	event, and enables the event trigger itself, after
 *	initializing it (via the event_trigger_ops @init() function).
 *	This is also where commands can use the @trigger_type value to
 *	make the decision as to whether or not multiple instances of
 *	the trigger should be allowed.  This is usually implemented by
 *	the generic utility function @register_trigger() (see
 *	trace_event_triggers.c).
 *
 * @unreg: Removes the trigger from the list of triggers associated
 *	with the event, and disables the event trigger itself, after
 *	initializing it (via the event_trigger_ops @free() function).
 *	This is usually implemented by the generic utility function
 *	@unregister_trigger() (see trace_event_triggers.c).
 *
 * @unreg_all: An optional function called to remove all the triggers
 *	from the list of triggers associated with the event.  Called
 *	when a trigger file is opened in truncate mode.
 *
 * @set_filter: An optional function called to parse and set a filter
 *	for the trigger.  If no @set_filter() method is set for the
 *	event command, filters set by the user for the command will be
 *	ignored.  This is usually implemented by the generic utility
 *	function @set_trigger_filter() (see trace_event_triggers.c).
 *
 * @get_trigger_ops: The callback function invoked to retrieve the
 *	event_trigger_ops implementation associated with the command.
 */
struct event_command {
	struct list_head	list;
	char			*name;
	enum event_trigger_type	trigger_type;
	int			flags;
	int			(*func)(struct event_command *cmd_ops,
					struct trace_event_file *file,
					char *glob, char *cmd, char *params);
	int			(*reg)(char *glob,
				       struct event_trigger_ops *ops,
				       struct event_trigger_data *data,
				       struct trace_event_file *file);
	void			(*unreg)(char *glob,
					 struct event_trigger_ops *ops,
					 struct event_trigger_data *data,
					 struct trace_event_file *file);
	void			(*unreg_all)(struct trace_event_file *file);
	int			(*set_filter)(char *filter_str,
					      struct event_trigger_data *data,
					      struct trace_event_file *file);
	struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
};

/**
 * enum event_command_flags - flags for struct event_command
 *
 * @POST_TRIGGER: A flag that says whether or not this command needs
 *	to have its action delayed until after the current event has
 *	been closed.  Some triggers need to avoid being invoked while
 *	an event is currently in the process of being logged, since
 *	the trigger may itself log data into the trace buffer.  Thus
 *	we make sure the current event is committed before invoking
 *	those triggers.  To do that, the trigger invocation is split
 *	in two - the first part checks the filter using the current
 *	trace record; if a command has the @post_trigger flag set, it
 *	sets a bit for itself in the return value, otherwise it
 *	directly invokes the trigger.  Once all commands have been
 *	either invoked or set their return flag, the current record is
 *	either committed or discarded.  At that point, if any commands
 *	have deferred their triggers, those commands are finally
 *	invoked following the close of the current event.  In other
 *	words, if the event_trigger_ops @func() probe implementation
 *	itself logs to the trace buffer, this flag should be set,
 *	otherwise it can be left unspecified.
 *
 * @NEEDS_REC: A flag that says whether or not this command needs
 *	access to the trace record in order to perform its function,
 *	regardless of whether or not it has a filter associated with
 *	it (filters make a trigger require access to the trace record
 *	but are not always present).
 */
enum event_command_flags {
	EVENT_CMD_FL_POST_TRIGGER	= 1,
	EVENT_CMD_FL_NEEDS_REC		= 2,
};

static inline bool event_command_post_trigger(struct event_command *cmd_ops)
{
	return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
}

static inline bool event_command_needs_rec(struct event_command *cmd_ops)
{
	return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
}

extern int trace_event_enable_disable(struct trace_event_file *file,
				      int enable, int soft_disable);
extern int tracing_alloc_snapshot(void);

extern const char *__start___trace_bprintk_fmt[];
extern const char *__stop___trace_bprintk_fmt[];

extern const char *__start___tracepoint_str[];
extern const char *__stop___tracepoint_str[];

void trace_printk_control(bool enabled);
void trace_printk_init_buffers(void);
void trace_printk_start_comm(void);
int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);

#define MAX_EVENT_NAME_LEN	64

extern int trace_run_command(const char *buf, int (*createfn)(int, char**));
extern ssize_t trace_parse_run_command(struct file *file,
		const char __user *buffer, size_t count, loff_t *ppos,
		int (*createfn)(int, char**));

/*
 * Normal trace_printk() and friends allocates special buffers
 * to do the manipulation, as well as saves the print formats
 * into sections to display. But the trace infrastructure wants
 * to use these without the added overhead at the price of being
 * a bit slower (used mainly for warnings, where we don't care
 * about performance). The internal_trace_puts() is for such
 * a purpose.
 */
#define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))

#undef FTRACE_ENTRY
#define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter)	\
	extern struct trace_event_call					\
	__aligned(4) event_##call;
#undef FTRACE_ENTRY_DUP
#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter)	\
	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
		     filter)
#undef FTRACE_ENTRY_PACKED
#define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print, filter) \
	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
		     filter)

#include "trace_entries.h"

#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
int perf_ftrace_event_register(struct trace_event_call *call,
			       enum trace_reg type, void *data);
#else
#define perf_ftrace_event_register NULL
#endif

#ifdef CONFIG_FTRACE_SYSCALLS
void init_ftrace_syscalls(void);
const char *get_syscall_name(int syscall);
#else
static inline void init_ftrace_syscalls(void) { }
static inline const char *get_syscall_name(int syscall)
{
	return NULL;
}
#endif

#ifdef CONFIG_EVENT_TRACING
void trace_event_init(void);
void trace_event_eval_update(struct trace_eval_map **map, int len);
#else
static inline void __init trace_event_init(void) { }
static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
#endif

#ifdef CONFIG_TRACER_SNAPSHOT
void tracing_snapshot_instance(struct trace_array *tr);
int tracing_alloc_snapshot_instance(struct trace_array *tr);
#else
static inline void tracing_snapshot_instance(struct trace_array *tr) { }
static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
{
	return 0;
}
#endif

extern struct trace_iterator *tracepoint_print_iter;

#endif /* _LINUX_KERNEL_TRACE_H */
OpenPOWER on IntegriCloud