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Commit | Line | Data |
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16444a8a | 1 | # |
606576ce SR |
2 | # Architectures that offer an FUNCTION_TRACER implementation should |
3 | # select HAVE_FUNCTION_TRACER: | |
16444a8a | 4 | # |
2a3a4f66 | 5 | |
8d26487f TE |
6 | config USER_STACKTRACE_SUPPORT |
7 | bool | |
8 | ||
2a3a4f66 FW |
9 | config NOP_TRACER |
10 | bool | |
11 | ||
78d904b4 SR |
12 | config HAVE_FTRACE_NMI_ENTER |
13 | bool | |
555f386c | 14 | help |
40892367 | 15 | See Documentation/trace/ftrace-design.txt |
78d904b4 | 16 | |
606576ce | 17 | config HAVE_FUNCTION_TRACER |
16444a8a | 18 | bool |
555f386c | 19 | help |
40892367 | 20 | See Documentation/trace/ftrace-design.txt |
bc0c38d1 | 21 | |
fb52607a | 22 | config HAVE_FUNCTION_GRAPH_TRACER |
15e6cb36 | 23 | bool |
555f386c | 24 | help |
40892367 | 25 | See Documentation/trace/ftrace-design.txt |
15e6cb36 | 26 | |
71e308a2 SR |
27 | config HAVE_FUNCTION_GRAPH_FP_TEST |
28 | bool | |
29 | help | |
03688970 | 30 | See Documentation/trace/ftrace-design.txt |
71e308a2 | 31 | |
60a7ecf4 SR |
32 | config HAVE_FUNCTION_TRACE_MCOUNT_TEST |
33 | bool | |
34 | help | |
40892367 | 35 | See Documentation/trace/ftrace-design.txt |
60a7ecf4 | 36 | |
677aa9f7 SR |
37 | config HAVE_DYNAMIC_FTRACE |
38 | bool | |
555f386c | 39 | help |
40892367 | 40 | See Documentation/trace/ftrace-design.txt |
677aa9f7 | 41 | |
8da3821b SR |
42 | config HAVE_FTRACE_MCOUNT_RECORD |
43 | bool | |
555f386c | 44 | help |
40892367 | 45 | See Documentation/trace/ftrace-design.txt |
8da3821b | 46 | |
66700001 | 47 | config HAVE_SYSCALL_TRACEPOINTS |
ee08c6ec | 48 | bool |
555f386c | 49 | help |
40892367 | 50 | See Documentation/trace/ftrace-design.txt |
ee08c6ec | 51 | |
352ad25a SR |
52 | config TRACER_MAX_TRACE |
53 | bool | |
54 | ||
7a8e76a3 SR |
55 | config RING_BUFFER |
56 | bool | |
57 | ||
78d904b4 SR |
58 | config FTRACE_NMI_ENTER |
59 | bool | |
60 | depends on HAVE_FTRACE_NMI_ENTER | |
61 | default y | |
62 | ||
5f77a88b | 63 | config EVENT_TRACING |
b11c53e1 Z |
64 | select CONTEXT_SWITCH_TRACER |
65 | bool | |
66 | ||
67 | config CONTEXT_SWITCH_TRACER | |
5f77a88b TZ |
68 | bool |
69 | ||
85bac32c SR |
70 | config RING_BUFFER_ALLOW_SWAP |
71 | bool | |
72 | help | |
73 | Allow the use of ring_buffer_swap_cpu. | |
74 | Adds a very slight overhead to tracing when enabled. | |
75 | ||
5e0a0939 SR |
76 | # All tracer options should select GENERIC_TRACER. For those options that are |
77 | # enabled by all tracers (context switch and event tracer) they select TRACING. | |
78 | # This allows those options to appear when no other tracer is selected. But the | |
79 | # options do not appear when something else selects it. We need the two options | |
80 | # GENERIC_TRACER and TRACING to avoid circular dependencies to accomplish the | |
40892367 | 81 | # hiding of the automatic options. |
5e0a0939 | 82 | |
bc0c38d1 SR |
83 | config TRACING |
84 | bool | |
85 | select DEBUG_FS | |
7a8e76a3 | 86 | select RING_BUFFER |
c2c80529 | 87 | select STACKTRACE if STACKTRACE_SUPPORT |
5f87f112 | 88 | select TRACEPOINTS |
f3384b28 | 89 | select NOP_TRACER |
769b0441 | 90 | select BINARY_PRINTF |
5f77a88b | 91 | select EVENT_TRACING |
bc0c38d1 | 92 | |
5e0a0939 SR |
93 | config GENERIC_TRACER |
94 | bool | |
95 | select TRACING | |
96 | ||
40ada30f IM |
97 | # |
98 | # Minimum requirements an architecture has to meet for us to | |
99 | # be able to offer generic tracing facilities: | |
100 | # | |
101 | config TRACING_SUPPORT | |
102 | bool | |
45b95608 AV |
103 | # PPC32 has no irqflags tracing support, but it can use most of the |
104 | # tracers anyway, they were tested to build and work. Note that new | |
105 | # exceptions to this list aren't welcomed, better implement the | |
106 | # irqflags tracing for your architecture. | |
107 | depends on TRACE_IRQFLAGS_SUPPORT || PPC32 | |
40ada30f | 108 | depends on STACKTRACE_SUPPORT |
422d3c7a | 109 | default y |
40ada30f IM |
110 | |
111 | if TRACING_SUPPORT | |
112 | ||
4ed9f071 SR |
113 | menuconfig FTRACE |
114 | bool "Tracers" | |
65b77242 | 115 | default y if DEBUG_KERNEL |
4ed9f071 | 116 | help |
40892367 | 117 | Enable the kernel tracing infrastructure. |
4ed9f071 SR |
118 | |
119 | if FTRACE | |
17d80fd0 | 120 | |
606576ce | 121 | config FUNCTION_TRACER |
1b29b018 | 122 | bool "Kernel Function Tracer" |
606576ce | 123 | depends on HAVE_FUNCTION_TRACER |
1b29b018 | 124 | select FRAME_POINTER |
4d7a077c | 125 | select KALLSYMS |
5e0a0939 | 126 | select GENERIC_TRACER |
35e8e302 | 127 | select CONTEXT_SWITCH_TRACER |
1b29b018 SR |
128 | help |
129 | Enable the kernel to trace every kernel function. This is done | |
130 | by using a compiler feature to insert a small, 5-byte No-Operation | |
40892367 | 131 | instruction at the beginning of every kernel function, which NOP |
1b29b018 SR |
132 | sequence is then dynamically patched into a tracer call when |
133 | tracing is enabled by the administrator. If it's runtime disabled | |
134 | (the bootup default), then the overhead of the instructions is very | |
135 | small and not measurable even in micro-benchmarks. | |
35e8e302 | 136 | |
fb52607a FW |
137 | config FUNCTION_GRAPH_TRACER |
138 | bool "Kernel Function Graph Tracer" | |
139 | depends on HAVE_FUNCTION_GRAPH_TRACER | |
15e6cb36 | 140 | depends on FUNCTION_TRACER |
eb4a0378 | 141 | depends on !X86_32 || !CC_OPTIMIZE_FOR_SIZE |
764f3b95 | 142 | default y |
15e6cb36 | 143 | help |
fb52607a FW |
144 | Enable the kernel to trace a function at both its return |
145 | and its entry. | |
692105b8 ML |
146 | Its first purpose is to trace the duration of functions and |
147 | draw a call graph for each thread with some information like | |
40892367 | 148 | the return value. This is done by setting the current return |
692105b8 | 149 | address on the current task structure into a stack of calls. |
15e6cb36 | 150 | |
bac429f0 | 151 | |
81d68a96 SR |
152 | config IRQSOFF_TRACER |
153 | bool "Interrupts-off Latency Tracer" | |
154 | default n | |
155 | depends on TRACE_IRQFLAGS_SUPPORT | |
156 | depends on GENERIC_TIME | |
157 | select TRACE_IRQFLAGS | |
5e0a0939 | 158 | select GENERIC_TRACER |
81d68a96 | 159 | select TRACER_MAX_TRACE |
85bac32c | 160 | select RING_BUFFER_ALLOW_SWAP |
81d68a96 SR |
161 | help |
162 | This option measures the time spent in irqs-off critical | |
163 | sections, with microsecond accuracy. | |
164 | ||
165 | The default measurement method is a maximum search, which is | |
166 | disabled by default and can be runtime (re-)started | |
167 | via: | |
168 | ||
156f5a78 | 169 | echo 0 > /sys/kernel/debug/tracing/tracing_max_latency |
81d68a96 | 170 | |
40892367 | 171 | (Note that kernel size and overhead increase with this option |
6cd8a4bb SR |
172 | enabled. This option and the preempt-off timing option can be |
173 | used together or separately.) | |
174 | ||
175 | config PREEMPT_TRACER | |
176 | bool "Preemption-off Latency Tracer" | |
177 | default n | |
178 | depends on GENERIC_TIME | |
179 | depends on PREEMPT | |
5e0a0939 | 180 | select GENERIC_TRACER |
6cd8a4bb | 181 | select TRACER_MAX_TRACE |
85bac32c | 182 | select RING_BUFFER_ALLOW_SWAP |
6cd8a4bb | 183 | help |
40892367 | 184 | This option measures the time spent in preemption-off critical |
6cd8a4bb SR |
185 | sections, with microsecond accuracy. |
186 | ||
187 | The default measurement method is a maximum search, which is | |
188 | disabled by default and can be runtime (re-)started | |
189 | via: | |
190 | ||
156f5a78 | 191 | echo 0 > /sys/kernel/debug/tracing/tracing_max_latency |
6cd8a4bb | 192 | |
40892367 | 193 | (Note that kernel size and overhead increase with this option |
6cd8a4bb SR |
194 | enabled. This option and the irqs-off timing option can be |
195 | used together or separately.) | |
196 | ||
f06c3810 IM |
197 | config SYSPROF_TRACER |
198 | bool "Sysprof Tracer" | |
4d2df795 | 199 | depends on X86 |
5e0a0939 | 200 | select GENERIC_TRACER |
b22f4858 | 201 | select CONTEXT_SWITCH_TRACER |
f06c3810 IM |
202 | help |
203 | This tracer provides the trace needed by the 'Sysprof' userspace | |
204 | tool. | |
205 | ||
352ad25a SR |
206 | config SCHED_TRACER |
207 | bool "Scheduling Latency Tracer" | |
5e0a0939 | 208 | select GENERIC_TRACER |
352ad25a SR |
209 | select CONTEXT_SWITCH_TRACER |
210 | select TRACER_MAX_TRACE | |
211 | help | |
212 | This tracer tracks the latency of the highest priority task | |
213 | to be scheduled in, starting from the point it has woken up. | |
214 | ||
897f17a6 SR |
215 | config ENABLE_DEFAULT_TRACERS |
216 | bool "Trace process context switches and events" | |
5e0a0939 | 217 | depends on !GENERIC_TRACER |
b77e38aa SR |
218 | select TRACING |
219 | help | |
40892367 | 220 | This tracer hooks to various trace points in the kernel, |
b77e38aa | 221 | allowing the user to pick and choose which trace point they |
897f17a6 | 222 | want to trace. It also includes the sched_switch tracer plugin. |
a7abe97f | 223 | |
ee08c6ec FW |
224 | config FTRACE_SYSCALLS |
225 | bool "Trace syscalls" | |
66700001 | 226 | depends on HAVE_SYSCALL_TRACEPOINTS |
5e0a0939 | 227 | select GENERIC_TRACER |
0ea1c415 | 228 | select KALLSYMS |
ee08c6ec FW |
229 | help |
230 | Basic tracer to catch the syscall entry and exit events. | |
231 | ||
2ed84eeb | 232 | config TRACE_BRANCH_PROFILING |
9ae5b879 | 233 | bool |
5e0a0939 | 234 | select GENERIC_TRACER |
9ae5b879 SR |
235 | |
236 | choice | |
237 | prompt "Branch Profiling" | |
238 | default BRANCH_PROFILE_NONE | |
239 | help | |
240 | The branch profiling is a software profiler. It will add hooks | |
241 | into the C conditionals to test which path a branch takes. | |
242 | ||
243 | The likely/unlikely profiler only looks at the conditions that | |
244 | are annotated with a likely or unlikely macro. | |
245 | ||
40892367 | 246 | The "all branch" profiler will profile every if-statement in the |
9ae5b879 | 247 | kernel. This profiler will also enable the likely/unlikely |
40892367 | 248 | profiler. |
9ae5b879 | 249 | |
40892367 RD |
250 | Either of the above profilers adds a bit of overhead to the system. |
251 | If unsure, choose "No branch profiling". | |
9ae5b879 SR |
252 | |
253 | config BRANCH_PROFILE_NONE | |
254 | bool "No branch profiling" | |
255 | help | |
40892367 RD |
256 | No branch profiling. Branch profiling adds a bit of overhead. |
257 | Only enable it if you want to analyse the branching behavior. | |
258 | Otherwise keep it disabled. | |
9ae5b879 SR |
259 | |
260 | config PROFILE_ANNOTATED_BRANCHES | |
261 | bool "Trace likely/unlikely profiler" | |
262 | select TRACE_BRANCH_PROFILING | |
1f0d69a9 SR |
263 | help |
264 | This tracer profiles all the the likely and unlikely macros | |
265 | in the kernel. It will display the results in: | |
266 | ||
156f5a78 | 267 | /sys/kernel/debug/tracing/profile_annotated_branch |
1f0d69a9 | 268 | |
40892367 | 269 | Note: this will add a significant overhead; only turn this |
1f0d69a9 SR |
270 | on if you need to profile the system's use of these macros. |
271 | ||
2bcd521a SR |
272 | config PROFILE_ALL_BRANCHES |
273 | bool "Profile all if conditionals" | |
9ae5b879 | 274 | select TRACE_BRANCH_PROFILING |
2bcd521a SR |
275 | help |
276 | This tracer profiles all branch conditions. Every if () | |
277 | taken in the kernel is recorded whether it hit or miss. | |
278 | The results will be displayed in: | |
279 | ||
156f5a78 | 280 | /sys/kernel/debug/tracing/profile_branch |
2bcd521a | 281 | |
9ae5b879 SR |
282 | This option also enables the likely/unlikely profiler. |
283 | ||
2bcd521a SR |
284 | This configuration, when enabled, will impose a great overhead |
285 | on the system. This should only be enabled when the system | |
40892367 | 286 | is to be analyzed in much detail. |
9ae5b879 | 287 | endchoice |
2bcd521a | 288 | |
2ed84eeb | 289 | config TRACING_BRANCHES |
52f232cb SR |
290 | bool |
291 | help | |
292 | Selected by tracers that will trace the likely and unlikely | |
293 | conditions. This prevents the tracers themselves from being | |
294 | profiled. Profiling the tracing infrastructure can only happen | |
295 | when the likelys and unlikelys are not being traced. | |
296 | ||
2ed84eeb | 297 | config BRANCH_TRACER |
52f232cb | 298 | bool "Trace likely/unlikely instances" |
2ed84eeb SR |
299 | depends on TRACE_BRANCH_PROFILING |
300 | select TRACING_BRANCHES | |
52f232cb SR |
301 | help |
302 | This traces the events of likely and unlikely condition | |
303 | calls in the kernel. The difference between this and the | |
304 | "Trace likely/unlikely profiler" is that this is not a | |
305 | histogram of the callers, but actually places the calling | |
306 | events into a running trace buffer to see when and where the | |
307 | events happened, as well as their results. | |
308 | ||
309 | Say N if unsure. | |
310 | ||
0722db01 P |
311 | config KSYM_TRACER |
312 | bool "Trace read and write access on kernel memory locations" | |
313 | depends on HAVE_HW_BREAKPOINT | |
314 | select TRACING | |
315 | help | |
316 | This tracer helps find read and write operations on any given kernel | |
317 | symbol i.e. /proc/kallsyms. | |
318 | ||
319 | config PROFILE_KSYM_TRACER | |
320 | bool "Profile all kernel memory accesses on 'watched' variables" | |
321 | depends on KSYM_TRACER | |
322 | help | |
323 | This tracer profiles kernel accesses on variables watched through the | |
324 | ksym tracer ftrace plugin. Depending upon the hardware, all read | |
325 | and write operations on kernel variables can be monitored for | |
326 | accesses. | |
327 | ||
328 | The results will be displayed in: | |
329 | /debugfs/tracing/profile_ksym | |
330 | ||
331 | Say N if unsure. | |
f3f47a67 | 332 | |
e5a81b62 SR |
333 | config STACK_TRACER |
334 | bool "Trace max stack" | |
606576ce | 335 | depends on HAVE_FUNCTION_TRACER |
606576ce | 336 | select FUNCTION_TRACER |
e5a81b62 | 337 | select STACKTRACE |
4d7a077c | 338 | select KALLSYMS |
e5a81b62 | 339 | help |
4519d9e5 | 340 | This special tracer records the maximum stack footprint of the |
156f5a78 | 341 | kernel and displays it in /sys/kernel/debug/tracing/stack_trace. |
4519d9e5 IM |
342 | |
343 | This tracer works by hooking into every function call that the | |
344 | kernel executes, and keeping a maximum stack depth value and | |
f38f1d2a SR |
345 | stack-trace saved. If this is configured with DYNAMIC_FTRACE |
346 | then it will not have any overhead while the stack tracer | |
347 | is disabled. | |
348 | ||
349 | To enable the stack tracer on bootup, pass in 'stacktrace' | |
350 | on the kernel command line. | |
351 | ||
352 | The stack tracer can also be enabled or disabled via the | |
353 | sysctl kernel.stack_tracer_enabled | |
4519d9e5 IM |
354 | |
355 | Say N if unsure. | |
e5a81b62 | 356 | |
e1d8aa9f FW |
357 | config WORKQUEUE_TRACER |
358 | bool "Trace workqueues" | |
5e0a0939 | 359 | select GENERIC_TRACER |
e1d8aa9f | 360 | help |
40892367 | 361 | The workqueue tracer provides some statistical information |
e1d8aa9f FW |
362 | about each cpu workqueue thread such as the number of the |
363 | works inserted and executed since their creation. It can help | |
40892367 | 364 | to evaluate the amount of work each of them has to perform. |
e1d8aa9f | 365 | For example it can help a developer to decide whether he should |
40892367 | 366 | choose a per-cpu workqueue instead of a singlethreaded one. |
e1d8aa9f | 367 | |
2db270a8 | 368 | config BLK_DEV_IO_TRACE |
40892367 | 369 | bool "Support for tracing block IO actions" |
2db270a8 | 370 | depends on SYSFS |
1dfba05d | 371 | depends on BLOCK |
2db270a8 FW |
372 | select RELAY |
373 | select DEBUG_FS | |
374 | select TRACEPOINTS | |
5e0a0939 | 375 | select GENERIC_TRACER |
2db270a8 FW |
376 | select STACKTRACE |
377 | help | |
378 | Say Y here if you want to be able to trace the block layer actions | |
379 | on a given queue. Tracing allows you to see any traffic happening | |
380 | on a block device queue. For more information (and the userspace | |
381 | support tools needed), fetch the blktrace tools from: | |
382 | ||
383 | git://git.kernel.dk/blktrace.git | |
384 | ||
385 | Tracing also is possible using the ftrace interface, e.g.: | |
386 | ||
387 | echo 1 > /sys/block/sda/sda1/trace/enable | |
388 | echo blk > /sys/kernel/debug/tracing/current_tracer | |
389 | cat /sys/kernel/debug/tracing/trace_pipe | |
390 | ||
391 | If unsure, say N. | |
36994e58 | 392 | |
77b44d1b | 393 | config KPROBE_EVENT |
413d37d1 | 394 | depends on KPROBES |
f850c30c | 395 | depends on HAVE_REGS_AND_STACK_ACCESS_API |
77b44d1b | 396 | bool "Enable kprobes-based dynamic events" |
413d37d1 | 397 | select TRACING |
77b44d1b | 398 | default y |
413d37d1 | 399 | help |
40892367 RD |
400 | This allows the user to add tracing events (similar to tracepoints) |
401 | on the fly via the ftrace interface. See | |
402 | Documentation/trace/kprobetrace.txt for more details. | |
77b44d1b MH |
403 | |
404 | Those events can be inserted wherever kprobes can probe, and record | |
405 | various register and memory values. | |
406 | ||
40892367 RD |
407 | This option is also required by perf-probe subcommand of perf tools. |
408 | If you want to use perf tools, this option is strongly recommended. | |
413d37d1 | 409 | |
3d083395 SR |
410 | config DYNAMIC_FTRACE |
411 | bool "enable/disable ftrace tracepoints dynamically" | |
606576ce | 412 | depends on FUNCTION_TRACER |
677aa9f7 | 413 | depends on HAVE_DYNAMIC_FTRACE |
3d083395 SR |
414 | default y |
415 | help | |
40892367 RD |
416 | This option will modify all the calls to ftrace dynamically |
417 | (will patch them out of the binary image and replace them | |
418 | with a No-Op instruction) as they are called. A table is | |
419 | created to dynamically enable them again. | |
3d083395 | 420 | |
40892367 RD |
421 | This way a CONFIG_FUNCTION_TRACER kernel is slightly larger, but |
422 | otherwise has native performance as long as no tracing is active. | |
3d083395 | 423 | |
40892367 RD |
424 | The changes to the code are done by a kernel thread that |
425 | wakes up once a second and checks to see if any ftrace calls | |
426 | were made. If so, it runs stop_machine (stops all CPUS) | |
427 | and modifies the code to jump over the call to ftrace. | |
60a11774 | 428 | |
bac429f0 SR |
429 | config FUNCTION_PROFILER |
430 | bool "Kernel function profiler" | |
493762fc | 431 | depends on FUNCTION_TRACER |
bac429f0 SR |
432 | default n |
433 | help | |
40892367 RD |
434 | This option enables the kernel function profiler. A file is created |
435 | in debugfs called function_profile_enabled which defaults to zero. | |
436 | When a 1 is echoed into this file profiling begins, and when a | |
437 | zero is entered, profiling stops. A "functions" file is created in | |
438 | the trace_stats directory; this file shows the list of functions that | |
439 | have been hit and their counters. | |
bac429f0 | 440 | |
40892367 | 441 | If in doubt, say N. |
bac429f0 | 442 | |
8da3821b SR |
443 | config FTRACE_MCOUNT_RECORD |
444 | def_bool y | |
445 | depends on DYNAMIC_FTRACE | |
446 | depends on HAVE_FTRACE_MCOUNT_RECORD | |
447 | ||
60a11774 SR |
448 | config FTRACE_SELFTEST |
449 | bool | |
450 | ||
451 | config FTRACE_STARTUP_TEST | |
452 | bool "Perform a startup test on ftrace" | |
5e0a0939 | 453 | depends on GENERIC_TRACER |
60a11774 SR |
454 | select FTRACE_SELFTEST |
455 | help | |
456 | This option performs a series of startup tests on ftrace. On bootup | |
457 | a series of tests are made to verify that the tracer is | |
458 | functioning properly. It will do tests on all the configured | |
459 | tracers of ftrace. | |
17d80fd0 | 460 | |
1f5a6b45 SR |
461 | config EVENT_TRACE_TEST_SYSCALLS |
462 | bool "Run selftest on syscall events" | |
463 | depends on FTRACE_STARTUP_TEST | |
464 | help | |
465 | This option will also enable testing every syscall event. | |
466 | It only enables the event and disables it and runs various loads | |
467 | with the event enabled. This adds a bit more time for kernel boot | |
468 | up since it runs this on every system call defined. | |
469 | ||
470 | TBD - enable a way to actually call the syscalls as we test their | |
471 | events | |
472 | ||
fe6f90e5 PP |
473 | config MMIOTRACE |
474 | bool "Memory mapped IO tracing" | |
40ada30f | 475 | depends on HAVE_MMIOTRACE_SUPPORT && PCI |
5e0a0939 | 476 | select GENERIC_TRACER |
fe6f90e5 PP |
477 | help |
478 | Mmiotrace traces Memory Mapped I/O access and is meant for | |
479 | debugging and reverse engineering. It is called from the ioremap | |
480 | implementation and works via page faults. Tracing is disabled by | |
481 | default and can be enabled at run-time. | |
482 | ||
4d1f4372 | 483 | See Documentation/trace/mmiotrace.txt. |
fe6f90e5 PP |
484 | If you are not helping to develop drivers, say N. |
485 | ||
486 | config MMIOTRACE_TEST | |
487 | tristate "Test module for mmiotrace" | |
488 | depends on MMIOTRACE && m | |
489 | help | |
490 | This is a dumb module for testing mmiotrace. It is very dangerous | |
491 | as it will write garbage to IO memory starting at a given address. | |
492 | However, it should be safe to use on e.g. unused portion of VRAM. | |
493 | ||
494 | Say N, unless you absolutely know what you are doing. | |
495 | ||
5092dbc9 SR |
496 | config RING_BUFFER_BENCHMARK |
497 | tristate "Ring buffer benchmark stress tester" | |
498 | depends on RING_BUFFER | |
499 | help | |
40892367 RD |
500 | This option creates a test to stress the ring buffer and benchmark it. |
501 | It creates its own ring buffer such that it will not interfere with | |
5092dbc9 SR |
502 | any other users of the ring buffer (such as ftrace). It then creates |
503 | a producer and consumer that will run for 10 seconds and sleep for | |
504 | 10 seconds. Each interval it will print out the number of events | |
505 | it recorded and give a rough estimate of how long each iteration took. | |
506 | ||
507 | It does not disable interrupts or raise its priority, so it may be | |
508 | affected by processes that are running. | |
509 | ||
40892367 | 510 | If unsure, say N. |
5092dbc9 | 511 | |
4ed9f071 | 512 | endif # FTRACE |
40ada30f IM |
513 | |
514 | endif # TRACING_SUPPORT | |
515 |