Training courses

Kernel and Embedded Linux

Bootlin training courses

Embedded Linux, kernel,
Yocto Project, Buildroot, real-time,
graphics, boot time, debugging...

Bootlin logo

Elixir Cross Referencer

   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
/*
 * Performance events:
 *
 *    Copyright (C) 2008-2009, Thomas Gleixner <tglx@linutronix.de>
 *    Copyright (C) 2008-2011, Red Hat, Inc., Ingo Molnar
 *    Copyright (C) 2008-2011, Red Hat, Inc., Peter Zijlstra
 *
 * Data type definitions, declarations, prototypes.
 *
 *    Started by: Thomas Gleixner and Ingo Molnar
 *
 * For licencing details see kernel-base/COPYING
 */
#ifndef _LINUX_PERF_EVENT_H
#define _LINUX_PERF_EVENT_H

#include <uapi/linux/perf_event.h>
#include <uapi/linux/bpf_perf_event.h>

/*
 * Kernel-internal data types and definitions:
 */

#ifdef CONFIG_PERF_EVENTS
# include <asm/perf_event.h>
# include <asm/local64.h>
#endif

struct perf_guest_info_callbacks {
	int				(*is_in_guest)(void);
	int				(*is_user_mode)(void);
	unsigned long			(*get_guest_ip)(void);
	void				(*handle_intel_pt_intr)(void);
};

#ifdef CONFIG_HAVE_HW_BREAKPOINT
#include <asm/hw_breakpoint.h>
#endif

#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/rculist.h>
#include <linux/rcupdate.h>
#include <linux/spinlock.h>
#include <linux/hrtimer.h>
#include <linux/fs.h>
#include <linux/pid_namespace.h>
#include <linux/workqueue.h>
#include <linux/ftrace.h>
#include <linux/cpu.h>
#include <linux/irq_work.h>
#include <linux/static_key.h>
#include <linux/jump_label_ratelimit.h>
#include <linux/atomic.h>
#include <linux/sysfs.h>
#include <linux/perf_regs.h>
#include <linux/cgroup.h>
#include <linux/refcount.h>
#include <asm/local.h>

struct perf_callchain_entry {
	__u64				nr;
	__u64				ip[0]; /* /proc/sys/kernel/perf_event_max_stack */
};

struct perf_callchain_entry_ctx {
	struct perf_callchain_entry *entry;
	u32			    max_stack;
	u32			    nr;
	short			    contexts;
	bool			    contexts_maxed;
};

typedef unsigned long (*perf_copy_f)(void *dst, const void *src,
				     unsigned long off, unsigned long len);

struct perf_raw_frag {
	union {
		struct perf_raw_frag	*next;
		unsigned long		pad;
	};
	perf_copy_f			copy;
	void				*data;
	u32				size;
} __packed;

struct perf_raw_record {
	struct perf_raw_frag		frag;
	u32				size;
};

/*
 * branch stack layout:
 *  nr: number of taken branches stored in entries[]
 *
 * Note that nr can vary from sample to sample
 * branches (to, from) are stored from most recent
 * to least recent, i.e., entries[0] contains the most
 * recent branch.
 */
struct perf_branch_stack {
	__u64				nr;
	struct perf_branch_entry	entries[0];
};

struct task_struct;

/*
 * extra PMU register associated with an event
 */
struct hw_perf_event_extra {
	u64		config;	/* register value */
	unsigned int	reg;	/* register address or index */
	int		alloc;	/* extra register already allocated */
	int		idx;	/* index in shared_regs->regs[] */
};

/**
 * struct hw_perf_event - performance event hardware details:
 */
struct hw_perf_event {
#ifdef CONFIG_PERF_EVENTS
	union {
		struct { /* hardware */
			u64		config;
			u64		last_tag;
			unsigned long	config_base;
			unsigned long	event_base;
			int		event_base_rdpmc;
			int		idx;
			int		last_cpu;
			int		flags;

			struct hw_perf_event_extra extra_reg;
			struct hw_perf_event_extra branch_reg;
		};
		struct { /* software */
			struct hrtimer	hrtimer;
		};
		struct { /* tracepoint */
			/* for tp_event->class */
			struct list_head	tp_list;
		};
		struct { /* amd_power */
			u64	pwr_acc;
			u64	ptsc;
		};
#ifdef CONFIG_HAVE_HW_BREAKPOINT
		struct { /* breakpoint */
			/*
			 * Crufty hack to avoid the chicken and egg
			 * problem hw_breakpoint has with context
			 * creation and event initalization.
			 */
			struct arch_hw_breakpoint	info;
			struct list_head		bp_list;
		};
#endif
		struct { /* amd_iommu */
			u8	iommu_bank;
			u8	iommu_cntr;
			u16	padding;
			u64	conf;
			u64	conf1;
		};
	};
	/*
	 * If the event is a per task event, this will point to the task in
	 * question. See the comment in perf_event_alloc().
	 */
	struct task_struct		*target;

	/*
	 * PMU would store hardware filter configuration
	 * here.
	 */
	void				*addr_filters;

	/* Last sync'ed generation of filters */
	unsigned long			addr_filters_gen;

/*
 * hw_perf_event::state flags; used to track the PERF_EF_* state.
 */
#define PERF_HES_STOPPED	0x01 /* the counter is stopped */
#define PERF_HES_UPTODATE	0x02 /* event->count up-to-date */
#define PERF_HES_ARCH		0x04

	int				state;

	/*
	 * The last observed hardware counter value, updated with a
	 * local64_cmpxchg() such that pmu::read() can be called nested.
	 */
	local64_t			prev_count;

	/*
	 * The period to start the next sample with.
	 */
	u64				sample_period;

	/*
	 * The period we started this sample with.
	 */
	u64				last_period;

	/*
	 * However much is left of the current period; note that this is
	 * a full 64bit value and allows for generation of periods longer
	 * than hardware might allow.
	 */
	local64_t			period_left;

	/*
	 * State for throttling the event, see __perf_event_overflow() and
	 * perf_adjust_freq_unthr_context().
	 */
	u64                             interrupts_seq;
	u64				interrupts;

	/*
	 * State for freq target events, see __perf_event_overflow() and
	 * perf_adjust_freq_unthr_context().
	 */
	u64				freq_time_stamp;
	u64				freq_count_stamp;
#endif
};

struct perf_event;

/*
 * Common implementation detail of pmu::{start,commit,cancel}_txn
 */
#define PERF_PMU_TXN_ADD  0x1		/* txn to add/schedule event on PMU */
#define PERF_PMU_TXN_READ 0x2		/* txn to read event group from PMU */

/**
 * pmu::capabilities flags
 */
#define PERF_PMU_CAP_NO_INTERRUPT		0x01
#define PERF_PMU_CAP_NO_NMI			0x02
#define PERF_PMU_CAP_AUX_NO_SG			0x04
#define PERF_PMU_CAP_EXTENDED_REGS		0x08
#define PERF_PMU_CAP_EXCLUSIVE			0x10
#define PERF_PMU_CAP_ITRACE			0x20
#define PERF_PMU_CAP_HETEROGENEOUS_CPUS		0x40
#define PERF_PMU_CAP_NO_EXCLUDE			0x80
#define PERF_PMU_CAP_AUX_OUTPUT			0x100

/**
 * struct pmu - generic performance monitoring unit
 */
struct pmu {
	struct list_head		entry;

	struct module			*module;
	struct device			*dev;
	const struct attribute_group	**attr_groups;
	const struct attribute_group	**attr_update;
	const char			*name;
	int				type;

	/*
	 * various common per-pmu feature flags
	 */
	int				capabilities;

	int __percpu			*pmu_disable_count;
	struct perf_cpu_context __percpu *pmu_cpu_context;
	atomic_t			exclusive_cnt; /* < 0: cpu; > 0: tsk */
	int				task_ctx_nr;
	int				hrtimer_interval_ms;

	/* number of address filters this PMU can do */
	unsigned int			nr_addr_filters;

	/*
	 * Fully disable/enable this PMU, can be used to protect from the PMI
	 * as well as for lazy/batch writing of the MSRs.
	 */
	void (*pmu_enable)		(struct pmu *pmu); /* optional */
	void (*pmu_disable)		(struct pmu *pmu); /* optional */

	/*
	 * Try and initialize the event for this PMU.
	 *
	 * Returns:
	 *  -ENOENT	-- @event is not for this PMU
	 *
	 *  -ENODEV	-- @event is for this PMU but PMU not present
	 *  -EBUSY	-- @event is for this PMU but PMU temporarily unavailable
	 *  -EINVAL	-- @event is for this PMU but @event is not valid
	 *  -EOPNOTSUPP -- @event is for this PMU, @event is valid, but not supported
	 *  -EACCES	-- @event is for this PMU, @event is valid, but no privileges
	 *
	 *  0		-- @event is for this PMU and valid
	 *
	 * Other error return values are allowed.
	 */
	int (*event_init)		(struct perf_event *event);

	/*
	 * Notification that the event was mapped or unmapped.  Called
	 * in the context of the mapping task.
	 */
	void (*event_mapped)		(struct perf_event *event, struct mm_struct *mm); /* optional */
	void (*event_unmapped)		(struct perf_event *event, struct mm_struct *mm); /* optional */

	/*
	 * Flags for ->add()/->del()/ ->start()/->stop(). There are
	 * matching hw_perf_event::state flags.
	 */
#define PERF_EF_START	0x01		/* start the counter when adding    */
#define PERF_EF_RELOAD	0x02		/* reload the counter when starting */
#define PERF_EF_UPDATE	0x04		/* update the counter when stopping */

	/*
	 * Adds/Removes a counter to/from the PMU, can be done inside a
	 * transaction, see the ->*_txn() methods.
	 *
	 * The add/del callbacks will reserve all hardware resources required
	 * to service the event, this includes any counter constraint
	 * scheduling etc.
	 *
	 * Called with IRQs disabled and the PMU disabled on the CPU the event
	 * is on.
	 *
	 * ->add() called without PERF_EF_START should result in the same state
	 *  as ->add() followed by ->stop().
	 *
	 * ->del() must always PERF_EF_UPDATE stop an event. If it calls
	 *  ->stop() that must deal with already being stopped without
	 *  PERF_EF_UPDATE.
	 */
	int  (*add)			(struct perf_event *event, int flags);
	void (*del)			(struct perf_event *event, int flags);

	/*
	 * Starts/Stops a counter present on the PMU.
	 *
	 * The PMI handler should stop the counter when perf_event_overflow()
	 * returns !0. ->start() will be used to continue.
	 *
	 * Also used to change the sample period.
	 *
	 * Called with IRQs disabled and the PMU disabled on the CPU the event
	 * is on -- will be called from NMI context with the PMU generates
	 * NMIs.
	 *
	 * ->stop() with PERF_EF_UPDATE will read the counter and update
	 *  period/count values like ->read() would.
	 *
	 * ->start() with PERF_EF_RELOAD will reprogram the the counter
	 *  value, must be preceded by a ->stop() with PERF_EF_UPDATE.
	 */
	void (*start)			(struct perf_event *event, int flags);
	void (*stop)			(struct perf_event *event, int flags);

	/*
	 * Updates the counter value of the event.
	 *
	 * For sampling capable PMUs this will also update the software period
	 * hw_perf_event::period_left field.
	 */
	void (*read)			(struct perf_event *event);

	/*
	 * Group events scheduling is treated as a transaction, add
	 * group events as a whole and perform one schedulability test.
	 * If the test fails, roll back the whole group
	 *
	 * Start the transaction, after this ->add() doesn't need to
	 * do schedulability tests.
	 *
	 * Optional.
	 */
	void (*start_txn)		(struct pmu *pmu, unsigned int txn_flags);
	/*
	 * If ->start_txn() disabled the ->add() schedulability test
	 * then ->commit_txn() is required to perform one. On success
	 * the transaction is closed. On error the transaction is kept
	 * open until ->cancel_txn() is called.
	 *
	 * Optional.
	 */
	int  (*commit_txn)		(struct pmu *pmu);
	/*
	 * Will cancel the transaction, assumes ->del() is called
	 * for each successful ->add() during the transaction.
	 *
	 * Optional.
	 */
	void (*cancel_txn)		(struct pmu *pmu);

	/*
	 * Will return the value for perf_event_mmap_page::index for this event,
	 * if no implementation is provided it will default to: event->hw.idx + 1.
	 */
	int (*event_idx)		(struct perf_event *event); /*optional */

	/*
	 * context-switches callback
	 */
	void (*sched_task)		(struct perf_event_context *ctx,
					bool sched_in);
	/*
	 * PMU specific data size
	 */
	size_t				task_ctx_size;


	/*
	 * Set up pmu-private data structures for an AUX area
	 */
	void *(*setup_aux)		(struct perf_event *event, void **pages,
					 int nr_pages, bool overwrite);
					/* optional */

	/*
	 * Free pmu-private AUX data structures
	 */
	void (*free_aux)		(void *aux); /* optional */

	/*
	 * Validate address range filters: make sure the HW supports the
	 * requested configuration and number of filters; return 0 if the
	 * supplied filters are valid, -errno otherwise.
	 *
	 * Runs in the context of the ioctl()ing process and is not serialized
	 * with the rest of the PMU callbacks.
	 */
	int (*addr_filters_validate)	(struct list_head *filters);
					/* optional */

	/*
	 * Synchronize address range filter configuration:
	 * translate hw-agnostic filters into hardware configuration in
	 * event::hw::addr_filters.
	 *
	 * Runs as a part of filter sync sequence that is done in ->start()
	 * callback by calling perf_event_addr_filters_sync().
	 *
	 * May (and should) traverse event::addr_filters::list, for which its
	 * caller provides necessary serialization.
	 */
	void (*addr_filters_sync)	(struct perf_event *event);
					/* optional */

	/*
	 * Check if event can be used for aux_output purposes for
	 * events of this PMU.
	 *
	 * Runs from perf_event_open(). Should return 0 for "no match"
	 * or non-zero for "match".
	 */
	int (*aux_output_match)		(struct perf_event *event);
					/* optional */

	/*
	 * Filter events for PMU-specific reasons.
	 */
	int (*filter_match)		(struct perf_event *event); /* optional */

	/*
	 * Check period value for PERF_EVENT_IOC_PERIOD ioctl.
	 */
	int (*check_period)		(struct perf_event *event, u64 value); /* optional */
};

enum perf_addr_filter_action_t {
	PERF_ADDR_FILTER_ACTION_STOP = 0,
	PERF_ADDR_FILTER_ACTION_START,
	PERF_ADDR_FILTER_ACTION_FILTER,
};

/**
 * struct perf_addr_filter - address range filter definition
 * @entry:	event's filter list linkage
 * @path:	object file's path for file-based filters
 * @offset:	filter range offset
 * @size:	filter range size (size==0 means single address trigger)
 * @action:	filter/start/stop
 *
 * This is a hardware-agnostic filter configuration as specified by the user.
 */
struct perf_addr_filter {
	struct list_head	entry;
	struct path		path;
	unsigned long		offset;
	unsigned long		size;
	enum perf_addr_filter_action_t	action;
};

/**
 * struct perf_addr_filters_head - container for address range filters
 * @list:	list of filters for this event
 * @lock:	spinlock that serializes accesses to the @list and event's
 *		(and its children's) filter generations.
 * @nr_file_filters:	number of file-based filters
 *
 * A child event will use parent's @list (and therefore @lock), so they are
 * bundled together; see perf_event_addr_filters().
 */
struct perf_addr_filters_head {
	struct list_head	list;
	raw_spinlock_t		lock;
	unsigned int		nr_file_filters;
};

struct perf_addr_filter_range {
	unsigned long		start;
	unsigned long		size;
};

/**
 * enum perf_event_state - the states of an event:
 */
enum perf_event_state {
	PERF_EVENT_STATE_DEAD		= -4,
	PERF_EVENT_STATE_EXIT		= -3,
	PERF_EVENT_STATE_ERROR		= -2,
	PERF_EVENT_STATE_OFF		= -1,
	PERF_EVENT_STATE_INACTIVE	=  0,
	PERF_EVENT_STATE_ACTIVE		=  1,
};

struct file;
struct perf_sample_data;

typedef void (*perf_overflow_handler_t)(struct perf_event *,
					struct perf_sample_data *,
					struct pt_regs *regs);

/*
 * Event capabilities. For event_caps and groups caps.
 *
 * PERF_EV_CAP_SOFTWARE: Is a software event.
 * PERF_EV_CAP_READ_ACTIVE_PKG: A CPU event (or cgroup event) that can be read
 * from any CPU in the package where it is active.
 */
#define PERF_EV_CAP_SOFTWARE		BIT(0)
#define PERF_EV_CAP_READ_ACTIVE_PKG	BIT(1)

#define SWEVENT_HLIST_BITS		8
#define SWEVENT_HLIST_SIZE		(1 << SWEVENT_HLIST_BITS)

struct swevent_hlist {
	struct hlist_head		heads[SWEVENT_HLIST_SIZE];
	struct rcu_head			rcu_head;
};

#define PERF_ATTACH_CONTEXT	0x01
#define PERF_ATTACH_GROUP	0x02
#define PERF_ATTACH_TASK	0x04
#define PERF_ATTACH_TASK_DATA	0x08
#define PERF_ATTACH_ITRACE	0x10

struct perf_cgroup;
struct ring_buffer;

struct pmu_event_list {
	raw_spinlock_t		lock;
	struct list_head	list;
};

#define for_each_sibling_event(sibling, event)			\
	if ((event)->group_leader == (event))			\
		list_for_each_entry((sibling), &(event)->sibling_list, sibling_list)

/**
 * struct perf_event - performance event kernel representation:
 */
struct perf_event {
#ifdef CONFIG_PERF_EVENTS
	/*
	 * entry onto perf_event_context::event_list;
	 *   modifications require ctx->lock
	 *   RCU safe iterations.
	 */
	struct list_head		event_entry;

	/*
	 * Locked for modification by both ctx->mutex and ctx->lock; holding
	 * either sufficies for read.
	 */
	struct list_head		sibling_list;
	struct list_head		active_list;
	/*
	 * Node on the pinned or flexible tree located at the event context;
	 */
	struct rb_node			group_node;
	u64				group_index;
	/*
	 * We need storage to track the entries in perf_pmu_migrate_context; we
	 * cannot use the event_entry because of RCU and we want to keep the
	 * group in tact which avoids us using the other two entries.
	 */
	struct list_head		migrate_entry;

	struct hlist_node		hlist_entry;
	struct list_head		active_entry;
	int				nr_siblings;

	/* Not serialized. Only written during event initialization. */
	int				event_caps;
	/* The cumulative AND of all event_caps for events in this group. */
	int				group_caps;

	struct perf_event		*group_leader;
	struct pmu			*pmu;
	void				*pmu_private;

	enum perf_event_state		state;
	unsigned int			attach_state;
	local64_t			count;
	atomic64_t			child_count;

	/*
	 * These are the total time in nanoseconds that the event
	 * has been enabled (i.e. eligible to run, and the task has
	 * been scheduled in, if this is a per-task event)
	 * and running (scheduled onto the CPU), respectively.
	 */
	u64				total_time_enabled;
	u64				total_time_running;
	u64				tstamp;

	/*
	 * timestamp shadows the actual context timing but it can
	 * be safely used in NMI interrupt context. It reflects the
	 * context time as it was when the event was last scheduled in.
	 *
	 * ctx_time already accounts for ctx->timestamp. Therefore to
	 * compute ctx_time for a sample, simply add perf_clock().
	 */
	u64				shadow_ctx_time;

	struct perf_event_attr		attr;
	u16				header_size;
	u16				id_header_size;
	u16				read_size;
	struct hw_perf_event		hw;

	struct perf_event_context	*ctx;
	atomic_long_t			refcount;

	/*
	 * These accumulate total time (in nanoseconds) that children
	 * events have been enabled and running, respectively.
	 */
	atomic64_t			child_total_time_enabled;
	atomic64_t			child_total_time_running;

	/*
	 * Protect attach/detach and child_list:
	 */
	struct mutex			child_mutex;
	struct list_head		child_list;
	struct perf_event		*parent;

	int				oncpu;
	int				cpu;

	struct list_head		owner_entry;
	struct task_struct		*owner;

	/* mmap bits */
	struct mutex			mmap_mutex;
	atomic_t			mmap_count;

	struct ring_buffer		*rb;
	struct list_head		rb_entry;
	unsigned long			rcu_batches;
	int				rcu_pending;

	/* poll related */
	wait_queue_head_t		waitq;
	struct fasync_struct		*fasync;

	/* delayed work for NMIs and such */
	int				pending_wakeup;
	int				pending_kill;
	int				pending_disable;
	struct irq_work			pending;

	atomic_t			event_limit;

	/* address range filters */
	struct perf_addr_filters_head	addr_filters;
	/* vma address array for file-based filders */
	struct perf_addr_filter_range	*addr_filter_ranges;
	unsigned long			addr_filters_gen;

	/* for aux_output events */
	struct perf_event		*aux_event;

	void (*destroy)(struct perf_event *);
	struct rcu_head			rcu_head;

	struct pid_namespace		*ns;
	u64				id;

	u64				(*clock)(void);
	perf_overflow_handler_t		overflow_handler;
	void				*overflow_handler_context;
#ifdef CONFIG_BPF_SYSCALL
	perf_overflow_handler_t		orig_overflow_handler;
	struct bpf_prog			*prog;
#endif

#ifdef CONFIG_EVENT_TRACING
	struct trace_event_call		*tp_event;
	struct event_filter		*filter;
#ifdef CONFIG_FUNCTION_TRACER
	struct ftrace_ops               ftrace_ops;
#endif
#endif

#ifdef CONFIG_CGROUP_PERF
	struct perf_cgroup		*cgrp; /* cgroup event is attach to */
#endif

	struct list_head		sb_list;
#endif /* CONFIG_PERF_EVENTS */
};


struct perf_event_groups {
	struct rb_root	tree;
	u64		index;
};

/**
 * struct perf_event_context - event context structure
 *
 * Used as a container for task events and CPU events as well:
 */
struct perf_event_context {
	struct pmu			*pmu;
	/*
	 * Protect the states of the events in the list,
	 * nr_active, and the list:
	 */
	raw_spinlock_t			lock;
	/*
	 * Protect the list of events.  Locking either mutex or lock
	 * is sufficient to ensure the list doesn't change; to change
	 * the list you need to lock both the mutex and the spinlock.
	 */
	struct mutex			mutex;

	struct list_head		active_ctx_list;
	struct perf_event_groups	pinned_groups;
	struct perf_event_groups	flexible_groups;
	struct list_head		event_list;

	struct list_head		pinned_active;
	struct list_head		flexible_active;

	int				nr_events;
	int				nr_active;
	int				is_active;
	int				nr_stat;
	int				nr_freq;
	int				rotate_disable;
	/*
	 * Set when nr_events != nr_active, except tolerant to events not
	 * necessary to be active due to scheduling constraints, such as cgroups.
	 */
	int				rotate_necessary;
	refcount_t			refcount;
	struct task_struct		*task;

	/*
	 * Context clock, runs when context enabled.
	 */
	u64				time;
	u64				timestamp;

	/*
	 * These fields let us detect when two contexts have both
	 * been cloned (inherited) from a common ancestor.
	 */
	struct perf_event_context	*parent_ctx;
	u64				parent_gen;
	u64				generation;
	int				pin_count;
#ifdef CONFIG_CGROUP_PERF
	int				nr_cgroups;	 /* cgroup evts */
#endif
	void				*task_ctx_data; /* pmu specific data */
	struct rcu_head			rcu_head;
};

/*
 * Number of contexts where an event can trigger:
 *	task, softirq, hardirq, nmi.
 */
#define PERF_NR_CONTEXTS	4

/**
 * struct perf_event_cpu_context - per cpu event context structure
 */
struct perf_cpu_context {
	struct perf_event_context	ctx;
	struct perf_event_context	*task_ctx;
	int				active_oncpu;
	int				exclusive;

	raw_spinlock_t			hrtimer_lock;
	struct hrtimer			hrtimer;
	ktime_t				hrtimer_interval;
	unsigned int			hrtimer_active;

#ifdef CONFIG_CGROUP_PERF
	struct perf_cgroup		*cgrp;
	struct list_head		cgrp_cpuctx_entry;
#endif

	struct list_head		sched_cb_entry;
	int				sched_cb_usage;

	int				online;
};

struct perf_output_handle {
	struct perf_event		*event;
	struct ring_buffer		*rb;
	unsigned long			wakeup;
	unsigned long			size;
	u64				aux_flags;
	union {
		void			*addr;
		unsigned long		head;
	};
	int				page;
};

struct bpf_perf_event_data_kern {
	bpf_user_pt_regs_t *regs;
	struct perf_sample_data *data;
	struct perf_event *event;
};

#ifdef CONFIG_CGROUP_PERF

/*
 * perf_cgroup_info keeps track of time_enabled for a cgroup.
 * This is a per-cpu dynamically allocated data structure.
 */
struct perf_cgroup_info {
	u64				time;
	u64				timestamp;
};

struct perf_cgroup {
	struct cgroup_subsys_state	css;
	struct perf_cgroup_info	__percpu *info;
};

/*
 * Must ensure cgroup is pinned (css_get) before calling
 * this function. In other words, we cannot call this function
 * if there is no cgroup event for the current CPU context.
 */
static inline struct perf_cgroup *
perf_cgroup_from_task(struct task_struct *task, struct perf_event_context *ctx)
{
	return container_of(task_css_check(task, perf_event_cgrp_id,
					   ctx ? lockdep_is_held(&ctx->lock)
					       : true),
			    struct perf_cgroup, css);
}
#endif /* CONFIG_CGROUP_PERF */

#ifdef CONFIG_PERF_EVENTS

extern void *perf_aux_output_begin(struct perf_output_handle *handle,
				   struct perf_event *event);
extern void perf_aux_output_end(struct perf_output_handle *handle,
				unsigned long size);
extern int perf_aux_output_skip(struct perf_output_handle *handle,
				unsigned long size);
extern void *perf_get_aux(struct perf_output_handle *handle);
extern void perf_aux_output_flag(struct perf_output_handle *handle, u64 flags);
extern void perf_event_itrace_started(struct perf_event *event);

extern int perf_pmu_register(struct pmu *pmu, const char *name, int type);
extern void perf_pmu_unregister(struct pmu *pmu);

extern int perf_num_counters(void);
extern const char *perf_pmu_name(void);
extern void __perf_event_task_sched_in(struct task_struct *prev,
				       struct task_struct *task);
extern void __perf_event_task_sched_out(struct task_struct *prev,
					struct task_struct *next);
extern int perf_event_init_task(struct task_struct *child);
extern void perf_event_exit_task(struct task_struct *child);
extern void perf_event_free_task(struct task_struct *task);
extern void perf_event_delayed_put(struct task_struct *task);
extern struct file *perf_event_get(unsigned int fd);
extern const struct perf_event *perf_get_event(struct file *file);
extern const struct perf_event_attr *perf_event_attrs(struct perf_event *event);
extern void perf_event_print_debug(void);
extern void perf_pmu_disable(struct pmu *pmu);
extern void perf_pmu_enable(struct pmu *pmu);
extern void perf_sched_cb_dec(struct pmu *pmu);
extern void perf_sched_cb_inc(struct pmu *pmu);
extern int perf_event_task_disable(void);
extern int perf_event_task_enable(void);

extern void perf_pmu_resched(struct pmu *pmu);

extern int perf_event_refresh(struct perf_event *event, int refresh);
extern void perf_event_update_userpage(struct perf_event *event);
extern int perf_event_release_kernel(struct perf_event *event);
extern struct perf_event *
perf_event_create_kernel_counter(struct perf_event_attr *attr,
				int cpu,
				struct task_struct *task,
				perf_overflow_handler_t callback,
				void *context);
extern void perf_pmu_migrate_context(struct pmu *pmu,
				int src_cpu, int dst_cpu);
int perf_event_read_local(struct perf_event *event, u64 *value,
			  u64 *enabled, u64 *running);
extern u64 perf_event_read_value(struct perf_event *event,
				 u64 *enabled, u64 *running);


struct perf_sample_data {
	/*
	 * Fields set by perf_sample_data_init(), group so as to
	 * minimize the cachelines touched.
	 */
	u64				addr;
	struct perf_raw_record		*raw;
	struct perf_branch_stack	*br_stack;
	u64				period;
	u64				weight;
	u64				txn;
	union  perf_mem_data_src	data_src;

	/*
	 * The other fields, optionally {set,used} by
	 * perf_{prepare,output}_sample().
	 */
	u64				type;
	u64				ip;
	struct {
		u32	pid;
		u32	tid;
	}				tid_entry;
	u64				time;
	u64				id;
	u64				stream_id;
	struct {
		u32	cpu;
		u32	reserved;
	}				cpu_entry;
	struct perf_callchain_entry	*callchain;

	/*
	 * regs_user may point to task_pt_regs or to regs_user_copy, depending
	 * on arch details.
	 */
	struct perf_regs		regs_user;
	struct pt_regs			regs_user_copy;

	struct perf_regs		regs_intr;
	u64				stack_user_size;

	u64				phys_addr;
} ____cacheline_aligned;

/* default value for data source */
#define PERF_MEM_NA (PERF_MEM_S(OP, NA)   |\
		    PERF_MEM_S(LVL, NA)   |\
		    PERF_MEM_S(SNOOP, NA) |\
		    PERF_MEM_S(LOCK, NA)  |\
		    PERF_MEM_S(TLB, NA))

static inline void perf_sample_data_init(struct perf_sample_data *data,
					 u64 addr, u64 period)
{
	/* remaining struct members initialized in perf_prepare_sample() */
	data->addr = addr;
	data->raw  = NULL;
	data->br_stack = NULL;
	data->period = period;
	data->weight = 0;
	data->data_src.val = PERF_MEM_NA;
	data->txn = 0;
}

extern void perf_output_sample(struct perf_output_handle *handle,
			       struct perf_event_header *header,
			       struct perf_sample_data *data,
			       struct perf_event *event);
extern void perf_prepare_sample(struct perf_event_header *header,
				struct perf_sample_data *data,
				struct perf_event *event,
				struct pt_regs *regs);

extern int perf_event_overflow(struct perf_event *event,
				 struct perf_sample_data *data,
				 struct pt_regs *regs);

extern void perf_event_output_forward(struct perf_event *event,
				     struct perf_sample_data *data,
				     struct pt_regs *regs);
extern void perf_event_output_backward(struct perf_event *event,
				       struct perf_sample_data *data,
				       struct pt_regs *regs);
extern int perf_event_output(struct perf_event *event,
			     struct perf_sample_data *data,
			     struct pt_regs *regs);

static inline bool
is_default_overflow_handler(struct perf_event *event)
{
	if (likely(event->overflow_handler == perf_event_output_forward))
		return true;
	if (unlikely(event->overflow_handler == perf_event_output_backward))
		return true;
	return false;
}

extern void
perf_event_header__init_id(struct perf_event_header *header,
			   struct perf_sample_data *data,
			   struct perf_event *event);
extern void
perf_event__output_id_sample(struct perf_event *event,
			     struct perf_output_handle *handle,
			     struct perf_sample_data *sample);

extern void
perf_log_lost_samples(struct perf_event *event, u64 lost);

static inline bool event_has_any_exclude_flag(struct perf_event *event)
{
	struct perf_event_attr *attr = &event->attr;

	return attr->exclude_idle || attr->exclude_user ||
	       attr->exclude_kernel || attr->exclude_hv ||
	       attr->exclude_guest || attr->exclude_host;
}

static inline bool is_sampling_event(struct perf_event *event)
{
	return event->attr.sample_period != 0;
}

/*
 * Return 1 for a software event, 0 for a hardware event
 */
static inline int is_software_event(struct perf_event *event)
{
	return event->event_caps & PERF_EV_CAP_SOFTWARE;
}

/*
 * Return 1 for event in sw context, 0 for event in hw context
 */
static inline int in_software_context(struct perf_event *event)
{
	return event->ctx->pmu->task_ctx_nr == perf_sw_context;
}

static inline int is_exclusive_pmu(struct pmu *pmu)
{
	return pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE;
}

extern struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX];

extern void ___perf_sw_event(u32, u64, struct pt_regs *, u64);
extern void __perf_sw_event(u32, u64, struct pt_regs *, u64);

#ifndef perf_arch_fetch_caller_regs
static inline void perf_arch_fetch_caller_regs(struct pt_regs *regs, unsigned long ip) { }
#endif

/*
 * When generating a perf sample in-line, instead of from an interrupt /
 * exception, we lack a pt_regs. This is typically used from software events
 * like: SW_CONTEXT_SWITCHES, SW_MIGRATIONS and the tie-in with tracepoints.
 *
 * We typically don't need a full set, but (for x86) do require:
 * - ip for PERF_SAMPLE_IP
 * - cs for user_mode() tests
 * - sp for PERF_SAMPLE_CALLCHAIN
 * - eflags for MISC bits and CALLCHAIN (see: perf_hw_regs())
 *
 * NOTE: assumes @regs is otherwise already 0 filled; this is important for
 * things like PERF_SAMPLE_REGS_INTR.
 */
static inline void perf_fetch_caller_regs(struct pt_regs *regs)
{
	perf_arch_fetch_caller_regs(regs, CALLER_ADDR0);
}

static __always_inline void
perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr)
{
	if (static_key_false(&perf_swevent_enabled[event_id]))
		__perf_sw_event(event_id, nr, regs, addr);
}

DECLARE_PER_CPU(struct pt_regs, __perf_regs[4]);

/*
 * 'Special' version for the scheduler, it hard assumes no recursion,
 * which is guaranteed by us not actually scheduling inside other swevents
 * because those disable preemption.
 */
static __always_inline void
perf_sw_event_sched(u32 event_id, u64 nr, u64 addr)
{
	if (static_key_false(&perf_swevent_enabled[event_id])) {
		struct pt_regs *regs = this_cpu_ptr(&__perf_regs[0]);

		perf_fetch_caller_regs(regs);
		___perf_sw_event(event_id, nr, regs, addr);
	}
}

extern struct static_key_false perf_sched_events;

static __always_inline bool
perf_sw_migrate_enabled(void)
{
	if (static_key_false(&perf_swevent_enabled[PERF_COUNT_SW_CPU_MIGRATIONS]))
		return true;
	return false;
}

static inline void perf_event_task_migrate(struct task_struct *task)
{
	if (perf_sw_migrate_enabled())
		task->sched_migrated = 1;
}

static inline void perf_event_task_sched_in(struct task_struct *prev,
					    struct task_struct *task)
{
	if (static_branch_unlikely(&perf_sched_events))
		__perf_event_task_sched_in(prev, task);

	if (perf_sw_migrate_enabled() && task->sched_migrated) {
		struct pt_regs *regs = this_cpu_ptr(&__perf_regs[0]);

		perf_fetch_caller_regs(regs);
		___perf_sw_event(PERF_COUNT_SW_CPU_MIGRATIONS, 1, regs, 0);
		task->sched_migrated = 0;
	}
}

static inline void perf_event_task_sched_out(struct task_struct *prev,
					     struct task_struct *next)
{
	perf_sw_event_sched(PERF_COUNT_SW_CONTEXT_SWITCHES, 1, 0);

	if (static_branch_unlikely(&perf_sched_events))
		__perf_event_task_sched_out(prev, next);
}

extern void perf_event_mmap(struct vm_area_struct *vma);

extern void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len,
			       bool unregister, const char *sym);
extern void perf_event_bpf_event(struct bpf_prog *prog,
				 enum perf_bpf_event_type type,
				 u16 flags);

extern struct perf_guest_info_callbacks *perf_guest_cbs;
extern int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *callbacks);
extern int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *callbacks);

extern void perf_event_exec(void);
extern void perf_event_comm(struct task_struct *tsk, bool exec);
extern void perf_event_namespaces(struct task_struct *tsk);
extern void perf_event_fork(struct task_struct *tsk);

/* Callchains */
DECLARE_PER_CPU(struct perf_callchain_entry, perf_callchain_entry);

extern void perf_callchain_user(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs);
extern void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs);
extern struct perf_callchain_entry *
get_perf_callchain(struct pt_regs *regs, u32 init_nr, bool kernel, bool user,
		   u32 max_stack, bool crosstask, bool add_mark);
extern struct perf_callchain_entry *perf_callchain(struct perf_event *event, struct pt_regs *regs);
extern int get_callchain_buffers(int max_stack);
extern void put_callchain_buffers(void);

extern int sysctl_perf_event_max_stack;
extern int sysctl_perf_event_max_contexts_per_stack;

static inline int perf_callchain_store_context(struct perf_callchain_entry_ctx *ctx, u64 ip)
{
	if (ctx->contexts < sysctl_perf_event_max_contexts_per_stack) {
		struct perf_callchain_entry *entry = ctx->entry;
		entry->ip[entry->nr++] = ip;
		++ctx->contexts;
		return 0;
	} else {
		ctx->contexts_maxed = true;
		return -1; /* no more room, stop walking the stack */
	}
}

static inline int perf_callchain_store(struct perf_callchain_entry_ctx *ctx, u64 ip)
{
	if (ctx->nr < ctx->max_stack && !ctx->contexts_maxed) {
		struct perf_callchain_entry *entry = ctx->entry;
		entry->ip[entry->nr++] = ip;
		++ctx->nr;
		return 0;
	} else {
		return -1; /* no more room, stop walking the stack */
	}
}

extern int sysctl_perf_event_paranoid;
extern int sysctl_perf_event_mlock;
extern int sysctl_perf_event_sample_rate;
extern int sysctl_perf_cpu_time_max_percent;

extern void perf_sample_event_took(u64 sample_len_ns);

extern int perf_proc_update_handler(struct ctl_table *table, int write,
		void __user *buffer, size_t *lenp,
		loff_t *ppos);
extern int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write,
		void __user *buffer, size_t *lenp,
		loff_t *ppos);

int perf_event_max_stack_handler(struct ctl_table *table, int write,
				 void __user *buffer, size_t *lenp, loff_t *ppos);

static inline bool perf_paranoid_tracepoint_raw(void)
{
	return sysctl_perf_event_paranoid > -1;
}

static inline bool perf_paranoid_cpu(void)
{
	return sysctl_perf_event_paranoid > 0;
}

static inline bool perf_paranoid_kernel(void)
{
	return sysctl_perf_event_paranoid > 1;
}

extern void perf_event_init(void);
extern void perf_tp_event(u16 event_type, u64 count, void *record,
			  int entry_size, struct pt_regs *regs,
			  struct hlist_head *head, int rctx,
			  struct task_struct *task);
extern void perf_bp_event(struct perf_event *event, void *data);

#ifndef perf_misc_flags
# define perf_misc_flags(regs) \
		(user_mode(regs) ? PERF_RECORD_MISC_USER : PERF_RECORD_MISC_KERNEL)
# define perf_instruction_pointer(regs)	instruction_pointer(regs)
#endif
#ifndef perf_arch_bpf_user_pt_regs
# define perf_arch_bpf_user_pt_regs(regs) regs
#endif

static inline bool has_branch_stack(struct perf_event *event)
{
	return event->attr.sample_type & PERF_SAMPLE_BRANCH_STACK;
}

static inline bool needs_branch_stack(struct perf_event *event)
{
	return event->attr.branch_sample_type != 0;
}

static inline bool has_aux(struct perf_event *event)
{
	return event->pmu->setup_aux;
}

static inline bool is_write_backward(struct perf_event *event)
{
	return !!event->attr.write_backward;
}

static inline bool has_addr_filter(struct perf_event *event)
{
	return event->pmu->nr_addr_filters;
}

/*
 * An inherited event uses parent's filters
 */
static inline struct perf_addr_filters_head *
perf_event_addr_filters(struct perf_event *event)
{
	struct perf_addr_filters_head *ifh = &event->addr_filters;

	if (event->parent)
		ifh = &event->parent->addr_filters;

	return ifh;
}

extern void perf_event_addr_filters_sync(struct perf_event *event);

extern int perf_output_begin(struct perf_output_handle *handle,
			     struct perf_event *event, unsigned int size);
extern int perf_output_begin_forward(struct perf_output_handle *handle,
				    struct perf_event *event,
				    unsigned int size);
extern int perf_output_begin_backward(struct perf_output_handle *handle,
				      struct perf_event *event,
				      unsigned int size);

extern void perf_output_end(struct perf_output_handle *handle);
extern unsigned int perf_output_copy(struct perf_output_handle *handle,
			     const void *buf, unsigned int len);
extern unsigned int perf_output_skip(struct perf_output_handle *handle,
				     unsigned int len);
extern int perf_swevent_get_recursion_context(void);
extern void perf_swevent_put_recursion_context(int rctx);
extern u64 perf_swevent_set_period(struct perf_event *event);
extern void perf_event_enable(struct perf_event *event);
extern void perf_event_disable(struct perf_event *event);
extern void perf_event_disable_local(struct perf_event *event);
extern void perf_event_disable_inatomic(struct perf_event *event);
extern void perf_event_task_tick(void);
extern int perf_event_account_interrupt(struct perf_event *event);
#else /* !CONFIG_PERF_EVENTS: */
static inline void *
perf_aux_output_begin(struct perf_output_handle *handle,
		      struct perf_event *event)				{ return NULL; }
static inline void
perf_aux_output_end(struct perf_output_handle *handle, unsigned long size)
									{ }
static inline int
perf_aux_output_skip(struct perf_output_handle *handle,
		     unsigned long size)				{ return -EINVAL; }
static inline void *
perf_get_aux(struct perf_output_handle *handle)				{ return NULL; }
static inline void
perf_event_task_migrate(struct task_struct *task)			{ }
static inline void
perf_event_task_sched_in(struct task_struct *prev,
			 struct task_struct *task)			{ }
static inline void
perf_event_task_sched_out(struct task_struct *prev,
			  struct task_struct *next)			{ }
static inline int perf_event_init_task(struct task_struct *child)	{ return 0; }
static inline void perf_event_exit_task(struct task_struct *child)	{ }
static inline void perf_event_free_task(struct task_struct *task)	{ }
static inline void perf_event_delayed_put(struct task_struct *task)	{ }
static inline struct file *perf_event_get(unsigned int fd)	{ return ERR_PTR(-EINVAL); }
static inline const struct perf_event *perf_get_event(struct file *file)
{
	return ERR_PTR(-EINVAL);
}
static inline const struct perf_event_attr *perf_event_attrs(struct perf_event *event)
{
	return ERR_PTR(-EINVAL);
}
static inline int perf_event_read_local(struct perf_event *event, u64 *value,
					u64 *enabled, u64 *running)
{
	return -EINVAL;
}
static inline void perf_event_print_debug(void)				{ }
static inline int perf_event_task_disable(void)				{ return -EINVAL; }
static inline int perf_event_task_enable(void)				{ return -EINVAL; }
static inline int perf_event_refresh(struct perf_event *event, int refresh)
{
	return -EINVAL;
}

static inline void
perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr)	{ }
static inline void
perf_sw_event_sched(u32 event_id, u64 nr, u64 addr)			{ }
static inline void
perf_bp_event(struct perf_event *event, void *data)			{ }

static inline int perf_register_guest_info_callbacks
(struct perf_guest_info_callbacks *callbacks)				{ return 0; }
static inline int perf_unregister_guest_info_callbacks
(struct perf_guest_info_callbacks *callbacks)				{ return 0; }

static inline void perf_event_mmap(struct vm_area_struct *vma)		{ }

typedef int (perf_ksymbol_get_name_f)(char *name, int name_len, void *data);
static inline void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len,
				      bool unregister, const char *sym)	{ }
static inline void perf_event_bpf_event(struct bpf_prog *prog,
					enum perf_bpf_event_type type,
					u16 flags)			{ }
static inline void perf_event_exec(void)				{ }
static inline void perf_event_comm(struct task_struct *tsk, bool exec)	{ }
static inline void perf_event_namespaces(struct task_struct *tsk)	{ }
static inline void perf_event_fork(struct task_struct *tsk)		{ }
static inline void perf_event_init(void)				{ }
static inline int  perf_swevent_get_recursion_context(void)		{ return -1; }
static inline void perf_swevent_put_recursion_context(int rctx)		{ }
static inline u64 perf_swevent_set_period(struct perf_event *event)	{ return 0; }
static inline void perf_event_enable(struct perf_event *event)		{ }
static inline void perf_event_disable(struct perf_event *event)		{ }
static inline int __perf_event_disable(void *info)			{ return -1; }
static inline void perf_event_task_tick(void)				{ }
static inline int perf_event_release_kernel(struct perf_event *event)	{ return 0; }
#endif

#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_CPU_SUP_INTEL)
extern void perf_restore_debug_store(void);
#else
static inline void perf_restore_debug_store(void)			{ }
#endif

static __always_inline bool perf_raw_frag_last(const struct perf_raw_frag *frag)
{
	return frag->pad < sizeof(u64);
}

#define perf_output_put(handle, x) perf_output_copy((handle), &(x), sizeof(x))

struct perf_pmu_events_attr {
	struct device_attribute attr;
	u64 id;
	const char *event_str;
};

struct perf_pmu_events_ht_attr {
	struct device_attribute			attr;
	u64					id;
	const char				*event_str_ht;
	const char				*event_str_noht;
};

ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr,
			      char *page);

#define PMU_EVENT_ATTR(_name, _var, _id, _show)				\
static struct perf_pmu_events_attr _var = {				\
	.attr = __ATTR(_name, 0444, _show, NULL),			\
	.id   =  _id,							\
};

#define PMU_EVENT_ATTR_STRING(_name, _var, _str)			    \
static struct perf_pmu_events_attr _var = {				    \
	.attr		= __ATTR(_name, 0444, perf_event_sysfs_show, NULL), \
	.id		= 0,						    \
	.event_str	= _str,						    \
};

#define PMU_FORMAT_ATTR(_name, _format)					\
static ssize_t								\
_name##_show(struct device *dev,					\
			       struct device_attribute *attr,		\
			       char *page)				\
{									\
	BUILD_BUG_ON(sizeof(_format) >= PAGE_SIZE);			\
	return sprintf(page, _format "\n");				\
}									\
									\
static struct device_attribute format_attr_##_name = __ATTR_RO(_name)

/* Performance counter hotplug functions */
#ifdef CONFIG_PERF_EVENTS
int perf_event_init_cpu(unsigned int cpu);
int perf_event_exit_cpu(unsigned int cpu);
#else
#define perf_event_init_cpu	NULL
#define perf_event_exit_cpu	NULL
#endif

#endif /* _LINUX_PERF_EVENT_H */