1#
2# Architectures that offer an FUNCTION_TRACER implementation should
3#  select HAVE_FUNCTION_TRACER:
4#
5
6config USER_STACKTRACE_SUPPORT
7	bool
8
9config NOP_TRACER
10	bool
11
12config HAVE_FTRACE_NMI_ENTER
13	bool
14	help
15	  See Documentation/trace/ftrace-design.txt
16
17config HAVE_FUNCTION_TRACER
18	bool
19	help
20	  See Documentation/trace/ftrace-design.txt
21
22config HAVE_FUNCTION_GRAPH_TRACER
23	bool
24	help
25	  See Documentation/trace/ftrace-design.txt
26
27config HAVE_FUNCTION_GRAPH_FP_TEST
28	bool
29	help
30	  See Documentation/trace/ftrace-design.txt
31
32config HAVE_FUNCTION_TRACE_MCOUNT_TEST
33	bool
34	help
35	  See Documentation/trace/ftrace-design.txt
36
37config HAVE_DYNAMIC_FTRACE
38	bool
39	help
40	  See Documentation/trace/ftrace-design.txt
41
42config HAVE_FTRACE_MCOUNT_RECORD
43	bool
44	help
45	  See Documentation/trace/ftrace-design.txt
46
47config HAVE_SYSCALL_TRACEPOINTS
48	bool
49	help
50	  See Documentation/trace/ftrace-design.txt
51
52config HAVE_C_RECORDMCOUNT
53	bool
54	help
55	  C version of recordmcount available?
56
57config TRACER_MAX_TRACE
58	bool
59
60config RING_BUFFER
61	bool
62
63config FTRACE_NMI_ENTER
64       bool
65       depends on HAVE_FTRACE_NMI_ENTER
66       default y
67
68config EVENT_TRACING
69	select CONTEXT_SWITCH_TRACER
70	bool
71
72config EVENT_POWER_TRACING_DEPRECATED
73	depends on EVENT_TRACING
74	bool "Deprecated power event trace API, to be removed"
75	default y
76	help
77	  Provides old power event types:
78	  C-state/idle accounting events:
79	  power:power_start
80	  power:power_end
81	  and old cpufreq accounting event:
82	  power:power_frequency
83	  This is for userspace compatibility
84	  and will vanish after 5 kernel iterations,
85	  namely 3.1.
86
87config CONTEXT_SWITCH_TRACER
88	bool
89
90config RING_BUFFER_ALLOW_SWAP
91	bool
92	help
93	 Allow the use of ring_buffer_swap_cpu.
94	 Adds a very slight overhead to tracing when enabled.
95
96# All tracer options should select GENERIC_TRACER. For those options that are
97# enabled by all tracers (context switch and event tracer) they select TRACING.
98# This allows those options to appear when no other tracer is selected. But the
99# options do not appear when something else selects it. We need the two options
100# GENERIC_TRACER and TRACING to avoid circular dependencies to accomplish the
101# hiding of the automatic options.
102
103config TRACING
104	bool
105	select DEBUG_FS
106	select RING_BUFFER
107	select STACKTRACE if STACKTRACE_SUPPORT
108	select TRACEPOINTS
109	select NOP_TRACER
110	select BINARY_PRINTF
111	select EVENT_TRACING
112
113config GENERIC_TRACER
114	bool
115	select TRACING
116
117#
118# Minimum requirements an architecture has to meet for us to
119# be able to offer generic tracing facilities:
120#
121config TRACING_SUPPORT
122	bool
123	# PPC32 has no irqflags tracing support, but it can use most of the
124	# tracers anyway, they were tested to build and work. Note that new
125	# exceptions to this list aren't welcomed, better implement the
126	# irqflags tracing for your architecture.
127	depends on TRACE_IRQFLAGS_SUPPORT || PPC32
128	depends on STACKTRACE_SUPPORT
129	default y
130
131if TRACING_SUPPORT
132
133menuconfig FTRACE
134	bool "Tracers"
135	default y if DEBUG_KERNEL
136	help
137	  Enable the kernel tracing infrastructure.
138
139if FTRACE
140
141config FUNCTION_TRACER
142	bool "Kernel Function Tracer"
143	depends on HAVE_FUNCTION_TRACER
144	select FRAME_POINTER if !ARM_UNWIND && !PPC && !S390 && !MICROBLAZE
145	select KALLSYMS
146	select GENERIC_TRACER
147	select CONTEXT_SWITCH_TRACER
148	help
149	  Enable the kernel to trace every kernel function. This is done
150	  by using a compiler feature to insert a small, 5-byte No-Operation
151	  instruction at the beginning of every kernel function, which NOP
152	  sequence is then dynamically patched into a tracer call when
153	  tracing is enabled by the administrator. If it's runtime disabled
154	  (the bootup default), then the overhead of the instructions is very
155	  small and not measurable even in micro-benchmarks.
156
157config FUNCTION_GRAPH_TRACER
158	bool "Kernel Function Graph Tracer"
159	depends on HAVE_FUNCTION_GRAPH_TRACER
160	depends on FUNCTION_TRACER
161	depends on !X86_32 || !CC_OPTIMIZE_FOR_SIZE
162	default y
163	help
164	  Enable the kernel to trace a function at both its return
165	  and its entry.
166	  Its first purpose is to trace the duration of functions and
167	  draw a call graph for each thread with some information like
168	  the return value. This is done by setting the current return
169	  address on the current task structure into a stack of calls.
170
171
172config IRQSOFF_TRACER
173	bool "Interrupts-off Latency Tracer"
174	default n
175	depends on TRACE_IRQFLAGS_SUPPORT
176	depends on !ARCH_USES_GETTIMEOFFSET
177	select TRACE_IRQFLAGS
178	select GENERIC_TRACER
179	select TRACER_MAX_TRACE
180	select RING_BUFFER_ALLOW_SWAP
181	help
182	  This option measures the time spent in irqs-off critical
183	  sections, with microsecond accuracy.
184
185	  The default measurement method is a maximum search, which is
186	  disabled by default and can be runtime (re-)started
187	  via:
188
189	      echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
190
191	  (Note that kernel size and overhead increase with this option
192	  enabled. This option and the preempt-off timing option can be
193	  used together or separately.)
194
195config PREEMPT_TRACER
196	bool "Preemption-off Latency Tracer"
197	default n
198	depends on !ARCH_USES_GETTIMEOFFSET
199	depends on PREEMPT
200	select GENERIC_TRACER
201	select TRACER_MAX_TRACE
202	select RING_BUFFER_ALLOW_SWAP
203	help
204	  This option measures the time spent in preemption-off critical
205	  sections, with microsecond accuracy.
206
207	  The default measurement method is a maximum search, which is
208	  disabled by default and can be runtime (re-)started
209	  via:
210
211	      echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
212
213	  (Note that kernel size and overhead increase with this option
214	  enabled. This option and the irqs-off timing option can be
215	  used together or separately.)
216
217config SCHED_TRACER
218	bool "Scheduling Latency Tracer"
219	select GENERIC_TRACER
220	select CONTEXT_SWITCH_TRACER
221	select TRACER_MAX_TRACE
222	help
223	  This tracer tracks the latency of the highest priority task
224	  to be scheduled in, starting from the point it has woken up.
225
226config ENABLE_DEFAULT_TRACERS
227	bool "Trace process context switches and events"
228	depends on !GENERIC_TRACER
229	select TRACING
230	help
231	  This tracer hooks to various trace points in the kernel,
232	  allowing the user to pick and choose which trace point they
233	  want to trace. It also includes the sched_switch tracer plugin.
234
235config FTRACE_SYSCALLS
236	bool "Trace syscalls"
237	depends on HAVE_SYSCALL_TRACEPOINTS
238	select GENERIC_TRACER
239	select KALLSYMS
240	help
241	  Basic tracer to catch the syscall entry and exit events.
242
243config TRACE_BRANCH_PROFILING
244	bool
245	select GENERIC_TRACER
246
247choice
248	prompt "Branch Profiling"
249	default BRANCH_PROFILE_NONE
250	help
251	 The branch profiling is a software profiler. It will add hooks
252	 into the C conditionals to test which path a branch takes.
253
254	 The likely/unlikely profiler only looks at the conditions that
255	 are annotated with a likely or unlikely macro.
256
257	 The "all branch" profiler will profile every if-statement in the
258	 kernel. This profiler will also enable the likely/unlikely
259	 profiler.
260
261	 Either of the above profilers adds a bit of overhead to the system.
262	 If unsure, choose "No branch profiling".
263
264config BRANCH_PROFILE_NONE
265	bool "No branch profiling"
266	help
267	  No branch profiling. Branch profiling adds a bit of overhead.
268	  Only enable it if you want to analyse the branching behavior.
269	  Otherwise keep it disabled.
270
271config PROFILE_ANNOTATED_BRANCHES
272	bool "Trace likely/unlikely profiler"
273	select TRACE_BRANCH_PROFILING
274	help
275	  This tracer profiles all the the likely and unlikely macros
276	  in the kernel. It will display the results in:
277
278	  /sys/kernel/debug/tracing/trace_stat/branch_annotated
279
280	  Note: this will add a significant overhead; only turn this
281	  on if you need to profile the system's use of these macros.
282
283config PROFILE_ALL_BRANCHES
284	bool "Profile all if conditionals"
285	select TRACE_BRANCH_PROFILING
286	help
287	  This tracer profiles all branch conditions. Every if ()
288	  taken in the kernel is recorded whether it hit or miss.
289	  The results will be displayed in:
290
291	  /sys/kernel/debug/tracing/trace_stat/branch_all
292
293	  This option also enables the likely/unlikely profiler.
294
295	  This configuration, when enabled, will impose a great overhead
296	  on the system. This should only be enabled when the system
297	  is to be analyzed in much detail.
298endchoice
299
300config TRACING_BRANCHES
301	bool
302	help
303	  Selected by tracers that will trace the likely and unlikely
304	  conditions. This prevents the tracers themselves from being
305	  profiled. Profiling the tracing infrastructure can only happen
306	  when the likelys and unlikelys are not being traced.
307
308config BRANCH_TRACER
309	bool "Trace likely/unlikely instances"
310	depends on TRACE_BRANCH_PROFILING
311	select TRACING_BRANCHES
312	help
313	  This traces the events of likely and unlikely condition
314	  calls in the kernel.  The difference between this and the
315	  "Trace likely/unlikely profiler" is that this is not a
316	  histogram of the callers, but actually places the calling
317	  events into a running trace buffer to see when and where the
318	  events happened, as well as their results.
319
320	  Say N if unsure.
321
322config STACK_TRACER
323	bool "Trace max stack"
324	depends on HAVE_FUNCTION_TRACER
325	select FUNCTION_TRACER
326	select STACKTRACE
327	select KALLSYMS
328	help
329	  This special tracer records the maximum stack footprint of the
330	  kernel and displays it in /sys/kernel/debug/tracing/stack_trace.
331
332	  This tracer works by hooking into every function call that the
333	  kernel executes, and keeping a maximum stack depth value and
334	  stack-trace saved.  If this is configured with DYNAMIC_FTRACE
335	  then it will not have any overhead while the stack tracer
336	  is disabled.
337
338	  To enable the stack tracer on bootup, pass in 'stacktrace'
339	  on the kernel command line.
340
341	  The stack tracer can also be enabled or disabled via the
342	  sysctl kernel.stack_tracer_enabled
343
344	  Say N if unsure.
345
346config BLK_DEV_IO_TRACE
347	bool "Support for tracing block IO actions"
348	depends on SYSFS
349	depends on BLOCK
350	select RELAY
351	select DEBUG_FS
352	select TRACEPOINTS
353	select GENERIC_TRACER
354	select STACKTRACE
355	help
356	  Say Y here if you want to be able to trace the block layer actions
357	  on a given queue. Tracing allows you to see any traffic happening
358	  on a block device queue. For more information (and the userspace
359	  support tools needed), fetch the blktrace tools from:
360
361	  git://git.kernel.dk/blktrace.git
362
363	  Tracing also is possible using the ftrace interface, e.g.:
364
365	    echo 1 > /sys/block/sda/sda1/trace/enable
366	    echo blk > /sys/kernel/debug/tracing/current_tracer
367	    cat /sys/kernel/debug/tracing/trace_pipe
368
369	  If unsure, say N.
370
371config KPROBE_EVENT
372	depends on KPROBES
373	depends on HAVE_REGS_AND_STACK_ACCESS_API
374	bool "Enable kprobes-based dynamic events"
375	select TRACING
376	default y
377	help
378	  This allows the user to add tracing events (similar to tracepoints)
379	  on the fly via the ftrace interface. See
380	  Documentation/trace/kprobetrace.txt for more details.
381
382	  Those events can be inserted wherever kprobes can probe, and record
383	  various register and memory values.
384
385	  This option is also required by perf-probe subcommand of perf tools.
386	  If you want to use perf tools, this option is strongly recommended.
387
388config DYNAMIC_FTRACE
389	bool "enable/disable function tracing dynamically"
390	depends on FUNCTION_TRACER
391	depends on HAVE_DYNAMIC_FTRACE
392	default y
393	help
394	  This option will modify all the calls to function tracing
395	  dynamically (will patch them out of the binary image and
396	  replace them with a No-Op instruction) on boot up. During
397	  compile time, a table is made of all the locations that ftrace
398	  can function trace, and this table is linked into the kernel
399	  image. When this is enabled, functions can be individually
400	  enabled, and the functions not enabled will not affect
401	  performance of the system.
402
403	  See the files in /sys/kernel/debug/tracing:
404	    available_filter_functions
405	    set_ftrace_filter
406	    set_ftrace_notrace
407
408	  This way a CONFIG_FUNCTION_TRACER kernel is slightly larger, but
409	  otherwise has native performance as long as no tracing is active.
410
411config FUNCTION_PROFILER
412	bool "Kernel function profiler"
413	depends on FUNCTION_TRACER
414	default n
415	help
416	  This option enables the kernel function profiler. A file is created
417	  in debugfs called function_profile_enabled which defaults to zero.
418	  When a 1 is echoed into this file profiling begins, and when a
419	  zero is entered, profiling stops. A "functions" file is created in
420	  the trace_stats directory; this file shows the list of functions that
421	  have been hit and their counters.
422
423	  If in doubt, say N.
424
425config FTRACE_MCOUNT_RECORD
426	def_bool y
427	depends on DYNAMIC_FTRACE
428	depends on HAVE_FTRACE_MCOUNT_RECORD
429
430config FTRACE_SELFTEST
431	bool
432
433config FTRACE_STARTUP_TEST
434	bool "Perform a startup test on ftrace"
435	depends on GENERIC_TRACER
436	select FTRACE_SELFTEST
437	help
438	  This option performs a series of startup tests on ftrace. On bootup
439	  a series of tests are made to verify that the tracer is
440	  functioning properly. It will do tests on all the configured
441	  tracers of ftrace.
442
443config EVENT_TRACE_TEST_SYSCALLS
444	bool "Run selftest on syscall events"
445	depends on FTRACE_STARTUP_TEST
446	help
447	 This option will also enable testing every syscall event.
448	 It only enables the event and disables it and runs various loads
449	 with the event enabled. This adds a bit more time for kernel boot
450	 up since it runs this on every system call defined.
451
452	 TBD - enable a way to actually call the syscalls as we test their
453	       events
454
455config MMIOTRACE
456	bool "Memory mapped IO tracing"
457	depends on HAVE_MMIOTRACE_SUPPORT && PCI
458	select GENERIC_TRACER
459	help
460	  Mmiotrace traces Memory Mapped I/O access and is meant for
461	  debugging and reverse engineering. It is called from the ioremap
462	  implementation and works via page faults. Tracing is disabled by
463	  default and can be enabled at run-time.
464
465	  See Documentation/trace/mmiotrace.txt.
466	  If you are not helping to develop drivers, say N.
467
468config MMIOTRACE_TEST
469	tristate "Test module for mmiotrace"
470	depends on MMIOTRACE && m
471	help
472	  This is a dumb module for testing mmiotrace. It is very dangerous
473	  as it will write garbage to IO memory starting at a given address.
474	  However, it should be safe to use on e.g. unused portion of VRAM.
475
476	  Say N, unless you absolutely know what you are doing.
477
478config RING_BUFFER_BENCHMARK
479	tristate "Ring buffer benchmark stress tester"
480	depends on RING_BUFFER
481	help
482	  This option creates a test to stress the ring buffer and benchmark it.
483	  It creates its own ring buffer such that it will not interfere with
484	  any other users of the ring buffer (such as ftrace). It then creates
485	  a producer and consumer that will run for 10 seconds and sleep for
486	  10 seconds. Each interval it will print out the number of events
487	  it recorded and give a rough estimate of how long each iteration took.
488
489	  It does not disable interrupts or raise its priority, so it may be
490	  affected by processes that are running.
491
492	  If unsure, say N.
493
494endif # FTRACE
495
496endif # TRACING_SUPPORT
497
498