1 # SPDX-License-Identifier: GPL-2.0-only
2 #
3 # Architectures that offer an FUNCTION_TRACER
4 # select HAVE_FUNCTION_TRACER:
5 #
6
7 config USER_STACKTRACE_SUPPORT
8 bool
9
10 config NOP_TRACER
11 bool
12
13 config HAVE_RETHOOK
14 bool
15
16 config RETHOOK
17 bool
18 depends on HAVE_RETHOOK
19 help
20 Enable generic return hooking featur
21 API, which will be used by other fun
22 features like fprobe and kprobes.
23
24 config HAVE_FUNCTION_TRACER
25 bool
26 help
27 See Documentation/trace/ftrace-desig
28
29 config HAVE_FUNCTION_GRAPH_TRACER
30 bool
31 help
32 See Documentation/trace/ftrace-desig
33
34 config HAVE_FUNCTION_GRAPH_RETVAL
35 bool
36
37 config HAVE_DYNAMIC_FTRACE
38 bool
39 help
40 See Documentation/trace/ftrace-desig
41
42 config HAVE_DYNAMIC_FTRACE_WITH_REGS
43 bool
44
45 config HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
46 bool
47
48 config HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS
49 bool
50
51 config HAVE_DYNAMIC_FTRACE_WITH_ARGS
52 bool
53 help
54 If this is set, then arguments and st
55 the ftrace_regs passed into the funct
56 by default, even without setting the
57 This allows for use of ftrace_regs_ge
58 ftrace_regs_get_stack_pointer().
59
60 config HAVE_DYNAMIC_FTRACE_NO_PATCHABLE
61 bool
62 help
63 If the architecture generates __patc
64 but does not want them included in t
65
66 config HAVE_FTRACE_MCOUNT_RECORD
67 bool
68 help
69 See Documentation/trace/ftrace-desig
70
71 config HAVE_SYSCALL_TRACEPOINTS
72 bool
73 help
74 See Documentation/trace/ftrace-desig
75
76 config HAVE_FENTRY
77 bool
78 help
79 Arch supports the gcc options -pg wi
80
81 config HAVE_NOP_MCOUNT
82 bool
83 help
84 Arch supports the gcc options -pg wi
85
86 config HAVE_OBJTOOL_MCOUNT
87 bool
88 help
89 Arch supports objtool --mcount
90
91 config HAVE_OBJTOOL_NOP_MCOUNT
92 bool
93 help
94 Arch supports the objtool options --
95 An architecture can select this if i
96 of ftrace locations.
97
98 config HAVE_C_RECORDMCOUNT
99 bool
100 help
101 C version of recordmcount available?
102
103 config HAVE_BUILDTIME_MCOUNT_SORT
104 bool
105 help
106 An architecture selects this if it so
107 at build time.
108
109 config BUILDTIME_MCOUNT_SORT
110 bool
111 default y
112 depends on HAVE_BUILDTIME_MCOUNT_SORT &
113 help
114 Sort the mcount_loc section at build
115
116 config TRACER_MAX_TRACE
117 bool
118
119 config TRACE_CLOCK
120 bool
121
122 config RING_BUFFER
123 bool
124 select TRACE_CLOCK
125 select IRQ_WORK
126
127 config EVENT_TRACING
128 select CONTEXT_SWITCH_TRACER
129 select GLOB
130 bool
131
132 config CONTEXT_SWITCH_TRACER
133 bool
134
135 config RING_BUFFER_ALLOW_SWAP
136 bool
137 help
138 Allow the use of ring_buffer_swap_cpu
139 Adds a very slight overhead to tracin
140
141 config PREEMPTIRQ_TRACEPOINTS
142 bool
143 depends on TRACE_PREEMPT_TOGGLE || TRA
144 select TRACING
145 default y
146 help
147 Create preempt/irq toggle tracepoint
148 of the kernel can use them to genera
149
150 # All tracer options should select GENERIC_TRA
151 # enabled by all tracers (context switch and e
152 # This allows those options to appear when no
153 # options do not appear when something else se
154 # GENERIC_TRACER and TRACING to avoid circular
155 # hiding of the automatic options.
156
157 config TRACING
158 bool
159 select RING_BUFFER
160 select STACKTRACE if STACKTRACE_SUPPOR
161 select TRACEPOINTS
162 select NOP_TRACER
163 select BINARY_PRINTF
164 select EVENT_TRACING
165 select TRACE_CLOCK
166 select NEED_TASKS_RCU
167
168 config GENERIC_TRACER
169 bool
170 select TRACING
171
172 #
173 # Minimum requirements an architecture has to
174 # be able to offer generic tracing facilities:
175 #
176 config TRACING_SUPPORT
177 bool
178 depends on TRACE_IRQFLAGS_SUPPORT
179 depends on STACKTRACE_SUPPORT
180 default y
181
182 menuconfig FTRACE
183 bool "Tracers"
184 depends on TRACING_SUPPORT
185 default y if DEBUG_KERNEL
186 help
187 Enable the kernel tracing infrastruc
188
189 if FTRACE
190
191 config BOOTTIME_TRACING
192 bool "Boot-time Tracing support"
193 depends on TRACING
194 select BOOT_CONFIG
195 help
196 Enable developer to setup ftrace sub
197 kernel cmdline at boot time for debu
198 initialization and boot process.
199
200 config FUNCTION_TRACER
201 bool "Kernel Function Tracer"
202 depends on HAVE_FUNCTION_TRACER
203 select KALLSYMS
204 select GENERIC_TRACER
205 select CONTEXT_SWITCH_TRACER
206 select GLOB
207 select NEED_TASKS_RCU
208 select TASKS_RUDE_RCU
209 help
210 Enable the kernel to trace every ker
211 by using a compiler feature to inser
212 instruction at the beginning of ever
213 sequence is then dynamically patched
214 tracing is enabled by the administra
215 (the bootup default), then the overh
216 small and not measurable even in mic
217 x86, but may have impact on other ar
218
219 config FUNCTION_GRAPH_TRACER
220 bool "Kernel Function Graph Tracer"
221 depends on HAVE_FUNCTION_GRAPH_TRACER
222 depends on FUNCTION_TRACER
223 depends on !X86_32 || !CC_OPTIMIZE_FOR
224 default y
225 help
226 Enable the kernel to trace a functio
227 and its entry.
228 Its first purpose is to trace the du
229 draw a call graph for each thread wi
230 the return value. This is done by se
231 address on the current task structur
232
233 config FUNCTION_GRAPH_RETVAL
234 bool "Kernel Function Graph Return Val
235 depends on HAVE_FUNCTION_GRAPH_RETVAL
236 depends on FUNCTION_GRAPH_TRACER
237 default n
238 help
239 Support recording and printing the f
240 using function graph tracer. It can
241 that return errors. This feature is
242 enable it via the trace option funcg
243 See Documentation/trace/ftrace.rst
244
245 config DYNAMIC_FTRACE
246 bool "enable/disable function tracing
247 depends on FUNCTION_TRACER
248 depends on HAVE_DYNAMIC_FTRACE
249 default y
250 help
251 This option will modify all the call
252 dynamically (will patch them out of
253 replace them with a No-Op instructio
254 compile time, a table is made of all
255 can function trace, and this table i
256 image. When this is enabled, functio
257 enabled, and the functions not enabl
258 performance of the system.
259
260 See the files in /sys/kernel/tracing
261 available_filter_functions
262 set_ftrace_filter
263 set_ftrace_notrace
264
265 This way a CONFIG_FUNCTION_TRACER ke
266 otherwise has native performance as
267
268 config DYNAMIC_FTRACE_WITH_REGS
269 def_bool y
270 depends on DYNAMIC_FTRACE
271 depends on HAVE_DYNAMIC_FTRACE_WITH_RE
272
273 config DYNAMIC_FTRACE_WITH_DIRECT_CALLS
274 def_bool y
275 depends on DYNAMIC_FTRACE_WITH_REGS ||
276 depends on HAVE_DYNAMIC_FTRACE_WITH_DI
277
278 config DYNAMIC_FTRACE_WITH_CALL_OPS
279 def_bool y
280 depends on HAVE_DYNAMIC_FTRACE_WITH_CA
281
282 config DYNAMIC_FTRACE_WITH_ARGS
283 def_bool y
284 depends on DYNAMIC_FTRACE
285 depends on HAVE_DYNAMIC_FTRACE_WITH_AR
286
287 config FPROBE
288 bool "Kernel Function Probe (fprobe)"
289 depends on FUNCTION_TRACER
290 depends on DYNAMIC_FTRACE_WITH_REGS
291 depends on HAVE_RETHOOK
292 select RETHOOK
293 default n
294 help
295 This option enables kernel function
296 The fprobe is similar to kprobes, bu
297 entries and exits. This also can pro
298 fprobe.
299
300 If unsure, say N.
301
302 config FUNCTION_PROFILER
303 bool "Kernel function profiler"
304 depends on FUNCTION_TRACER
305 default n
306 help
307 This option enables the kernel funct
308 in debugfs called function_profile_e
309 When a 1 is echoed into this file pr
310 zero is entered, profiling stops. A
311 the trace_stat directory; this file
312 have been hit and their counters.
313
314 If in doubt, say N.
315
316 config STACK_TRACER
317 bool "Trace max stack"
318 depends on HAVE_FUNCTION_TRACER
319 select FUNCTION_TRACER
320 select STACKTRACE
321 select KALLSYMS
322 help
323 This special tracer records the maxi
324 kernel and displays it in /sys/kerne
325
326 This tracer works by hooking into ev
327 kernel executes, and keeping a maxim
328 stack-trace saved. If this is confi
329 then it will not have any overhead w
330 is disabled.
331
332 To enable the stack tracer on bootup
333 on the kernel command line.
334
335 The stack tracer can also be enabled
336 sysctl kernel.stack_tracer_enabled
337
338 Say N if unsure.
339
340 config TRACE_PREEMPT_TOGGLE
341 bool
342 help
343 Enables hooks which will be called w
344 and last enabled.
345
346 config IRQSOFF_TRACER
347 bool "Interrupts-off Latency Tracer"
348 default n
349 depends on TRACE_IRQFLAGS_SUPPORT
350 select TRACE_IRQFLAGS
351 select GENERIC_TRACER
352 select TRACER_MAX_TRACE
353 select RING_BUFFER_ALLOW_SWAP
354 select TRACER_SNAPSHOT
355 select TRACER_SNAPSHOT_PER_CPU_SWAP
356 help
357 This option measures the time spent
358 sections, with microsecond accuracy.
359
360 The default measurement method is a
361 disabled by default and can be runti
362 via:
363
364 echo 0 > /sys/kernel/tracing/tra
365
366 (Note that kernel size and overhead
367 enabled. This option and the preempt
368 used together or separately.)
369
370 config PREEMPT_TRACER
371 bool "Preemption-off Latency Tracer"
372 default n
373 depends on PREEMPTION
374 select GENERIC_TRACER
375 select TRACER_MAX_TRACE
376 select RING_BUFFER_ALLOW_SWAP
377 select TRACER_SNAPSHOT
378 select TRACER_SNAPSHOT_PER_CPU_SWAP
379 select TRACE_PREEMPT_TOGGLE
380 help
381 This option measures the time spent
382 sections, with microsecond accuracy.
383
384 The default measurement method is a
385 disabled by default and can be runti
386 via:
387
388 echo 0 > /sys/kernel/tracing/tra
389
390 (Note that kernel size and overhead
391 enabled. This option and the irqs-of
392 used together or separately.)
393
394 config SCHED_TRACER
395 bool "Scheduling Latency Tracer"
396 select GENERIC_TRACER
397 select CONTEXT_SWITCH_TRACER
398 select TRACER_MAX_TRACE
399 select TRACER_SNAPSHOT
400 help
401 This tracer tracks the latency of th
402 to be scheduled in, starting from th
403
404 config HWLAT_TRACER
405 bool "Tracer to detect hardware latenc
406 select GENERIC_TRACER
407 select TRACER_MAX_TRACE
408 help
409 This tracer, when enabled will create
410 depending on what the cpumask file is
411 spinning in a loop looking for interr
412 something other than the kernel. For
413 System Management Interrupt (SMI) tak
414 time, this tracer will detect it. Thi
415 if a system is reliable for Real Time
416
417 Some files are created in the tracing
418 is enabled:
419
420 hwlat_detector/width - time in us
421 hwlat_detector/window - time in us
422 iteration
423
424 A kernel thread is created that will
425 for "width" microseconds in every "wi
426 for "window - width" microseconds, wh
427 continue to operate.
428
429 The output will appear in the trace a
430
431 When the tracer is not running, it ha
432 but when it is running, it can cause
433 periodically non responsive. Do not r
434 production system.
435
436 To enable this tracer, echo in "hwlat
437 file. Every time a latency is greater
438 be recorded into the ring buffer.
439
440 config OSNOISE_TRACER
441 bool "OS Noise tracer"
442 select GENERIC_TRACER
443 select TRACER_MAX_TRACE
444 help
445 In the context of high-performance c
446 System Noise (osnoise) refers to the
447 application due to activities inside
448 context of Linux, NMIs, IRQs, SoftIR
449 can cause noise to the system. Moreo
450 also cause noise, for example, via S
451
452 The osnoise tracer leverages the hwl
453 loop with preemption, SoftIRQs and I
454 the sources of osnoise during its ex
455 note of the entry and exit point of
456 increasing a per-cpu interference co
457 counter for each source of interfere
458 NMI, IRQs, SoftIRQs, and threads is
459 observes these interferences' entry
460 without any interference from the op
461 hardware noise counter increases, po
462 noise. In this way, osnoise can acco
463 interference. At the end of the peri
464 the sum of all noise, the max single
465 available for the thread, and the co
466
467 In addition to the tracer, a set of
468 facilitate the identification of the
469
470 The output will appear in the trace
471
472 To enable this tracer, echo in "osno
473 file.
474
475 config TIMERLAT_TRACER
476 bool "Timerlat tracer"
477 select OSNOISE_TRACER
478 select GENERIC_TRACER
479 help
480 The timerlat tracer aims to help the
481 to find sources of wakeup latencies
482
483 The tracer creates a per-cpu kernel
484 The tracer thread sets a periodic ti
485 to sleep waiting for the timer to fi
486 then computes a wakeup latency value
487 the current time and the absolute ti
488 to expire.
489
490 The tracer prints two lines at every
491 timer latency observed at the hardir
492 activation of the thread. The second
493 by the thread, which is the same lev
494 ACTIVATION ID field serves to relate
495 respective thread execution.
496
497 The tracer is build on top of osnois
498 events can be used to trace the sour
499 IRQs and other threads. It also enab
500 stacktrace at the IRQ context, which
501 path that can cause thread delay.
502
503 config MMIOTRACE
504 bool "Memory mapped IO tracing"
505 depends on HAVE_MMIOTRACE_SUPPORT && P
506 select GENERIC_TRACER
507 help
508 Mmiotrace traces Memory Mapped I/O a
509 debugging and reverse engineering. I
510 implementation and works via page fa
511 default and can be enabled at run-ti
512
513 See Documentation/trace/mmiotrace.rs
514 If you are not helping to develop dr
515
516 config ENABLE_DEFAULT_TRACERS
517 bool "Trace process context switches a
518 depends on !GENERIC_TRACER
519 select TRACING
520 help
521 This tracer hooks to various trace p
522 allowing the user to pick and choose
523 want to trace. It also includes the
524
525 config FTRACE_SYSCALLS
526 bool "Trace syscalls"
527 depends on HAVE_SYSCALL_TRACEPOINTS
528 select GENERIC_TRACER
529 select KALLSYMS
530 help
531 Basic tracer to catch the syscall en
532
533 config TRACER_SNAPSHOT
534 bool "Create a snapshot trace buffer"
535 select TRACER_MAX_TRACE
536 help
537 Allow tracing users to take snapshot
538 ftrace interface, e.g.:
539
540 echo 1 > /sys/kernel/tracing/sna
541 cat snapshot
542
543 config TRACER_SNAPSHOT_PER_CPU_SWAP
544 bool "Allow snapshot to swap per CPU"
545 depends on TRACER_SNAPSHOT
546 select RING_BUFFER_ALLOW_SWAP
547 help
548 Allow doing a snapshot of a single C
549 full swap (all buffers). If this is
550 allowed:
551
552 echo 1 > /sys/kernel/tracing/per
553
554 After which, only the tracing buffer
555 the main tracing buffer, and the oth
556
557 When this is enabled, this adds a li
558 trace recording, as it needs to add
559 recording with swaps. But this does
560 of the overall system. This is enabl
561 or irq latency tracers are enabled,
562 and already adds the overhead (plus
563
564 config TRACE_BRANCH_PROFILING
565 bool
566 select GENERIC_TRACER
567
568 choice
569 prompt "Branch Profiling"
570 default BRANCH_PROFILE_NONE
571 help
572 The branch profiling is a software pr
573 into the C conditionals to test which
574
575 The likely/unlikely profiler only loo
576 are annotated with a likely or unlike
577
578 The "all branch" profiler will profil
579 kernel. This profiler will also enabl
580 profiler.
581
582 Either of the above profilers adds a
583 If unsure, choose "No branch profilin
584
585 config BRANCH_PROFILE_NONE
586 bool "No branch profiling"
587 help
588 No branch profiling. Branch profilin
589 Only enable it if you want to analys
590 Otherwise keep it disabled.
591
592 config PROFILE_ANNOTATED_BRANCHES
593 bool "Trace likely/unlikely profiler"
594 select TRACE_BRANCH_PROFILING
595 help
596 This tracer profiles all likely and
597 in the kernel. It will display the r
598
599 /sys/kernel/tracing/trace_stat/branc
600
601 Note: this will add a significant ov
602 on if you need to profile the system
603
604 config PROFILE_ALL_BRANCHES
605 bool "Profile all if conditionals" if
606 select TRACE_BRANCH_PROFILING
607 help
608 This tracer profiles all branch cond
609 taken in the kernel is recorded whet
610 The results will be displayed in:
611
612 /sys/kernel/tracing/trace_stat/branc
613
614 This option also enables the likely/
615
616 This configuration, when enabled, wi
617 on the system. This should only be e
618 is to be analyzed in much detail.
619 endchoice
620
621 config TRACING_BRANCHES
622 bool
623 help
624 Selected by tracers that will trace
625 conditions. This prevents the tracer
626 profiled. Profiling the tracing infr
627 when the likelys and unlikelys are n
628
629 config BRANCH_TRACER
630 bool "Trace likely/unlikely instances"
631 depends on TRACE_BRANCH_PROFILING
632 select TRACING_BRANCHES
633 help
634 This traces the events of likely and
635 calls in the kernel. The difference
636 "Trace likely/unlikely profiler" is
637 histogram of the callers, but actual
638 events into a running trace buffer t
639 events happened, as well as their re
640
641 Say N if unsure.
642
643 config BLK_DEV_IO_TRACE
644 bool "Support for tracing block IO act
645 depends on SYSFS
646 depends on BLOCK
647 select RELAY
648 select DEBUG_FS
649 select TRACEPOINTS
650 select GENERIC_TRACER
651 select STACKTRACE
652 help
653 Say Y here if you want to be able to
654 on a given queue. Tracing allows you
655 on a block device queue. For more in
656 support tools needed), fetch the blk
657
658 git://git.kernel.dk/blktrace.git
659
660 Tracing also is possible using the f
661
662 echo 1 > /sys/block/sda/sda1/trace
663 echo blk > /sys/kernel/tracing/cur
664 cat /sys/kernel/tracing/trace_pipe
665
666 If unsure, say N.
667
668 config FPROBE_EVENTS
669 depends on FPROBE
670 depends on HAVE_REGS_AND_STACK_ACCESS_
671 bool "Enable fprobe-based dynamic even
672 select TRACING
673 select PROBE_EVENTS
674 select DYNAMIC_EVENTS
675 default y
676 help
677 This allows user to add tracing even
678 exit via ftrace interface. The synta
679 and the kprobe events on function en
680 transparently converted to this fpro
681
682 config PROBE_EVENTS_BTF_ARGS
683 depends on HAVE_FUNCTION_ARG_ACCESS_AP
684 depends on FPROBE_EVENTS || KPROBE_EVE
685 depends on DEBUG_INFO_BTF && BPF_SYSCA
686 bool "Support BTF function arguments f
687 default y
688 help
689 The user can specify the arguments o
690 of the arguments of the probed funct
691 kernel function entry or a tracepoin
692 This is available only if BTF (BPF T
693
694 config KPROBE_EVENTS
695 depends on KPROBES
696 depends on HAVE_REGS_AND_STACK_ACCESS_
697 bool "Enable kprobes-based dynamic eve
698 select TRACING
699 select PROBE_EVENTS
700 select DYNAMIC_EVENTS
701 default y
702 help
703 This allows the user to add tracing
704 on the fly via the ftrace interface.
705 Documentation/trace/kprobetrace.rst
706
707 Those events can be inserted whereve
708 various register and memory values.
709
710 This option is also required by perf
711 If you want to use perf tools, this
712
713 config KPROBE_EVENTS_ON_NOTRACE
714 bool "Do NOT protect notrace function
715 depends on KPROBE_EVENTS
716 depends on DYNAMIC_FTRACE
717 default n
718 help
719 This is only for the developers who
720 using kprobe events.
721
722 If kprobes can use ftrace instead of
723 functions are protected from kprobe-
724 recursion or any unexpected executio
725 crash.
726
727 This option disables such protection
728 events on ftrace functions for debug
729 Note that this might let you shoot y
730
731 If unsure, say N.
732
733 config UPROBE_EVENTS
734 bool "Enable uprobes-based dynamic eve
735 depends on ARCH_SUPPORTS_UPROBES
736 depends on MMU
737 depends on PERF_EVENTS
738 select UPROBES
739 select PROBE_EVENTS
740 select DYNAMIC_EVENTS
741 select TRACING
742 default y
743 help
744 This allows the user to add tracing
745 dynamic events (similar to tracepoin
746 events interface. Those events can b
747 can probe, and record various regist
748 This option is required if you plan
749 of perf tools on user space applicat
750
751 config BPF_EVENTS
752 depends on BPF_SYSCALL
753 depends on (KPROBE_EVENTS || UPROBE_EV
754 bool
755 default y
756 help
757 This allows the user to attach BPF p
758 tracepoint events.
759
760 config DYNAMIC_EVENTS
761 def_bool n
762
763 config PROBE_EVENTS
764 def_bool n
765
766 config BPF_KPROBE_OVERRIDE
767 bool "Enable BPF programs to override
768 depends on BPF_EVENTS
769 depends on FUNCTION_ERROR_INJECTION
770 default n
771 help
772 Allows BPF to override the execution
773 set a different return value. This i
774
775 config FTRACE_MCOUNT_RECORD
776 def_bool y
777 depends on DYNAMIC_FTRACE
778 depends on HAVE_FTRACE_MCOUNT_RECORD
779
780 config FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_EN
781 bool
782 depends on FTRACE_MCOUNT_RECORD
783
784 config FTRACE_MCOUNT_USE_CC
785 def_bool y
786 depends on $(cc-option,-mrecord-mcount
787 depends on !FTRACE_MCOUNT_USE_PATCHABL
788 depends on FTRACE_MCOUNT_RECORD
789
790 config FTRACE_MCOUNT_USE_OBJTOOL
791 def_bool y
792 depends on HAVE_OBJTOOL_MCOUNT
793 depends on !FTRACE_MCOUNT_USE_PATCHABL
794 depends on !FTRACE_MCOUNT_USE_CC
795 depends on FTRACE_MCOUNT_RECORD
796 select OBJTOOL
797
798 config FTRACE_MCOUNT_USE_RECORDMCOUNT
799 def_bool y
800 depends on !FTRACE_MCOUNT_USE_PATCHABL
801 depends on !FTRACE_MCOUNT_USE_CC
802 depends on !FTRACE_MCOUNT_USE_OBJTOOL
803 depends on FTRACE_MCOUNT_RECORD
804
805 config TRACING_MAP
806 bool
807 depends on ARCH_HAVE_NMI_SAFE_CMPXCHG
808 help
809 tracing_map is a special-purpose loc
810 separated out as a stand-alone facil
811 to be shared between multiple tracer
812 generally used outside of that conte
813 selected by tracers that use it.
814
815 config SYNTH_EVENTS
816 bool "Synthetic trace events"
817 select TRACING
818 select DYNAMIC_EVENTS
819 default n
820 help
821 Synthetic events are user-defined tr
822 used to combine data from other trac
823 data source. Synthetic events can b
824 via the trace() action of histogram
825 by way of an in-kernel API.
826
827 See Documentation/trace/events.rst o
828 Documentation/trace/histogram.rst fo
829
830 If in doubt, say N.
831
832 config USER_EVENTS
833 bool "User trace events"
834 select TRACING
835 select DYNAMIC_EVENTS
836 help
837 User trace events are user-defined t
838 can be used like an existing kernel
839 events are generated by writing to a
840 processes can determine if their tra
841 generated by registering a value and
842 that reflects when it is enabled or
843
844 See Documentation/trace/user_events.
845 If in doubt, say N.
846
847 config HIST_TRIGGERS
848 bool "Histogram triggers"
849 depends on ARCH_HAVE_NMI_SAFE_CMPXCHG
850 select TRACING_MAP
851 select TRACING
852 select DYNAMIC_EVENTS
853 select SYNTH_EVENTS
854 default n
855 help
856 Hist triggers allow one or more arbi
857 to be aggregated into hash tables an
858 reading a debugfs/tracefs file. The
859 gathering quick and dirty (though pr
860 event activity as an initial guide f
861 using more advanced tools.
862
863 Inter-event tracing of quantities su
864 supported using hist triggers under
865
866 See Documentation/trace/histogram.rs
867 If in doubt, say N.
868
869 config TRACE_EVENT_INJECT
870 bool "Trace event injection"
871 depends on TRACING
872 help
873 Allow user-space to inject a specifi
874 buffer. This is mainly used for test
875
876 If unsure, say N.
877
878 config TRACEPOINT_BENCHMARK
879 bool "Add tracepoint that benchmarks t
880 help
881 This option creates the tracepoint "b
882 When the tracepoint is enabled, it ki
883 goes into an infinite loop (calling c
884 run), and calls the tracepoint. Each
885 it took to write to the tracepoint an
886 data will be passed to the tracepoint
887 will report the time it took to do th
888 The string written to the tracepoint
889 to keep the time the same. The initia
890 "START". The second string records th
891 write which is not added to the rest
892
893 As it is a tight loop, it benchmarks
894 we care most about hot paths that are
895
896 An example of the output:
897
898 START
899 first=3672 [COLD CACHED]
900 last=632 first=3672 max=632 min=
901 last=278 first=3672 max=632 min=
902 last=277 first=3672 max=632 min=
903 last=273 first=3672 max=632 min=
904 last=273 first=3672 max=632 min=
905 last=281 first=3672 max=632 min=
906
907
908 config RING_BUFFER_BENCHMARK
909 tristate "Ring buffer benchmark stress
910 depends on RING_BUFFER
911 help
912 This option creates a test to stress
913 It creates its own ring buffer such
914 any other users of the ring buffer (
915 a producer and consumer that will ru
916 10 seconds. Each interval it will pr
917 it recorded and give a rough estimat
918
919 It does not disable interrupts or ra
920 affected by processes that are runni
921
922 If unsure, say N.
923
924 config TRACE_EVAL_MAP_FILE
925 bool "Show eval mappings for trace even
926 depends on TRACING
927 help
928 The "print fmt" of the trace events wi
929 instead of their values. This can caus
930 that use this string to parse the raw
931 how to convert the string to its value
932
933 To fix this, there's a special macro i
934 to convert an enum/sizeof into its val
935 the print fmt strings will be converte
936
937 If something does not get converted pr
938 used to show what enums/sizeof the ker
939
940 This option is for debugging the conve
941 in the tracing directory called "eval_
942 names matched with their values and wh
943 belong too.
944
945 Normally, the mapping of the strings t
946 boot up or module load. With this opti
947 they are needed for the "eval_map" fil
948 increase the memory footprint of the r
949
950 If unsure, say N.
951
952 config FTRACE_RECORD_RECURSION
953 bool "Record functions that recurse in
954 depends on FUNCTION_TRACER
955 help
956 All callbacks that attach to the fun
957 of protection against recursion. Eve
958 it adds overhead. This option will c
959 file system called "recursed_functio
960 that triggered a recursion.
961
962 This will add more overhead to cases
963
964 If unsure, say N
965
966 config FTRACE_RECORD_RECURSION_SIZE
967 int "Max number of recursed functions
968 default 128
969 depends on FTRACE_RECORD_RECURSION
970 help
971 This defines the limit of number of
972 listed in the "recursed_functions" f
973 the functions that caused a recursio
974 This file can be reset, but the limi
975 size at runtime.
976
977 config FTRACE_VALIDATE_RCU_IS_WATCHING
978 bool "Validate RCU is on during ftrace
979 depends on FUNCTION_TRACER
980 depends on ARCH_WANTS_NO_INSTR
981 help
982 All callbacks that attach to the fun
983 protection against recursion. This o
984 ftrace (and other users of ftrace_te
985 called outside of RCU, as if they ar
986 also has a noticeable overhead when
987
988 If unsure, say N
989
990 config RING_BUFFER_RECORD_RECURSION
991 bool "Record functions that recurse in
992 depends on FTRACE_RECORD_RECURSION
993 # default y, because it is coupled wit
994 default y
995 help
996 The ring buffer has its own internal
997 recursion happens it won't cause har
998 but it does cause unwanted overhead.
999 place where recursion was detected i
1000 file.
1001
1002 This will add more overhead to case
1003
1004 config GCOV_PROFILE_FTRACE
1005 bool "Enable GCOV profiling on ftrace
1006 depends on GCOV_KERNEL
1007 help
1008 Enable GCOV profiling on ftrace sub
1009 which functions/lines are tested.
1010
1011 If unsure, say N.
1012
1013 Note that on a kernel compiled with
1014 run significantly slower.
1015
1016 config FTRACE_SELFTEST
1017 bool
1018
1019 config FTRACE_STARTUP_TEST
1020 bool "Perform a startup test on ftrac
1021 depends on GENERIC_TRACER
1022 select FTRACE_SELFTEST
1023 help
1024 This option performs a series of st
1025 a series of tests are made to verif
1026 functioning properly. It will do te
1027 tracers of ftrace.
1028
1029 config EVENT_TRACE_STARTUP_TEST
1030 bool "Run selftest on trace events"
1031 depends on FTRACE_STARTUP_TEST
1032 default y
1033 help
1034 This option performs a test on all
1035 It basically just enables each even
1036 will trigger events (not necessaril
1037 This may take some time run as ther
1038
1039 config EVENT_TRACE_TEST_SYSCALLS
1040 bool "Run selftest on syscall events"
1041 depends on EVENT_TRACE_STARTUP_TEST
1042 help
1043 This option will also enable testing
1044 It only enables the event and disabl
1045 with the event enabled. This adds a
1046 up since it runs this on every syste
1047
1048 TBD - enable a way to actually call
1049 events
1050
1051 config FTRACE_SORT_STARTUP_TEST
1052 bool "Verify compile time sorting of f
1053 depends on DYNAMIC_FTRACE
1054 depends on BUILDTIME_MCOUNT_SORT
1055 help
1056 Sorting of the mcount_loc sections t
1057 where the ftrace knows where to patc
1058 and other callbacks is done at compi
1059 is not done correctly, it will cause
1060 When this is set, the sorted section
1061 are in deed sorted and will warn if
1062
1063 If unsure, say N
1064
1065 config RING_BUFFER_STARTUP_TEST
1066 bool "Ring buffer startup self test"
1067 depends on RING_BUFFER
1068 help
1069 Run a simple self test on the ring b
1070 kernel boot sequence, the test will
1071 a thread per cpu. Each thread will w
1072 into the ring buffer. Another thread
1073 to each of the threads, where the IP
1074 to the ring buffer, to test/stress t
1075 If any anomalies are discovered, a w
1076 and all ring buffers will be disable
1077
1078 The test runs for 10 seconds. This w
1079 by at least 10 more seconds.
1080
1081 At the end of the test, statistics a
1082 It will output the stats of each per
1083 was written, the sizes, what was rea
1084 other similar details.
1085
1086 If unsure, say N
1087
1088 config RING_BUFFER_VALIDATE_TIME_DELTAS
1089 bool "Verify ring buffer time stamp d
1090 depends on RING_BUFFER
1091 help
1092 This will audit the time stamps on
1093 buffer to make sure that all the ti
1094 events on a sub buffer matches the
1095 This audit is performed for every e
1096 interrupted, or interrupting anothe
1097 is also made when traversing sub bu
1098 that all the deltas on the previous
1099 add up to be greater than the curre
1100
1101 NOTE: This adds significant overhea
1102 and should only be used to test the
1103 Do not use it on production systems
1104
1105 Only say Y if you understand what t
1106 still want it enabled. Otherwise sa
1107
1108 config MMIOTRACE_TEST
1109 tristate "Test module for mmiotrace"
1110 depends on MMIOTRACE && m
1111 help
1112 This is a dumb module for testing m
1113 as it will write garbage to IO memo
1114 However, it should be safe to use o
1115
1116 Say N, unless you absolutely know w
1117
1118 config PREEMPTIRQ_DELAY_TEST
1119 tristate "Test module to create a pre
1120 depends on m
1121 help
1122 Select this option to build a test
1123 tracers by executing a preempt or i
1124 configurable delay. The module busy
1125 critical section.
1126
1127 For example, the following invocati
1128 irq-disabled critical sections for
1129 modprobe preemptirq_delay_test test
1130
1131 What's more, if you want to attach
1132 tracer is running on, specify cpu_a
1133 command.
1134
1135 If unsure, say N
1136
1137 config SYNTH_EVENT_GEN_TEST
1138 tristate "Test module for in-kernel s
1139 depends on SYNTH_EVENTS && m
1140 help
1141 This option creates a test module t
1142 functionality of in-kernel syntheti
1143 generation.
1144
1145 To test, insert the module, and the
1146 for the generated sample events.
1147
1148 If unsure, say N.
1149
1150 config KPROBE_EVENT_GEN_TEST
1151 tristate "Test module for in-kernel k
1152 depends on KPROBE_EVENTS && m
1153 help
1154 This option creates a test module t
1155 functionality of in-kernel kprobe e
1156
1157 To test, insert the module, and the
1158 for the generated kprobe events.
1159
1160 If unsure, say N.
1161
1162 config HIST_TRIGGERS_DEBUG
1163 bool "Hist trigger debug support"
1164 depends on HIST_TRIGGERS
1165 help
1166 Add "hist_debug" file for each even
1167 dump out a bunch of internal detail
1168 defined on that event.
1169
1170 The hist_debug file serves a couple
1171
1172 - Helps developers verify that no
1173
1174 - Provides educational informatio
1175 of the hist trigger internals a
1176 Documentation/trace/histogram-d
1177
1178 The hist_debug output only covers t
1179 related to the histogram definition
1180 display the internals of map bucket
1181 running histograms.
1182
1183 If unsure, say N.
1184
1185 source "kernel/trace/rv/Kconfig"
1186
1187 endif # FTRACE
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