Kconfig 24 KB

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  1. #
  2. # Architectures that offer an FUNCTION_TRACER implementation should
  3. # select HAVE_FUNCTION_TRACER:
  4. #
  5. config USER_STACKTRACE_SUPPORT
  6. bool
  7. config NOP_TRACER
  8. bool
  9. config HAVE_FTRACE_NMI_ENTER
  10. bool
  11. help
  12. See Documentation/trace/ftrace-design.txt
  13. config HAVE_FUNCTION_TRACER
  14. bool
  15. help
  16. See Documentation/trace/ftrace-design.txt
  17. config HAVE_FUNCTION_GRAPH_TRACER
  18. bool
  19. help
  20. See Documentation/trace/ftrace-design.txt
  21. config HAVE_DYNAMIC_FTRACE
  22. bool
  23. help
  24. See Documentation/trace/ftrace-design.txt
  25. config HAVE_DYNAMIC_FTRACE_WITH_REGS
  26. bool
  27. config HAVE_FTRACE_MCOUNT_RECORD
  28. bool
  29. help
  30. See Documentation/trace/ftrace-design.txt
  31. config HAVE_SYSCALL_TRACEPOINTS
  32. bool
  33. help
  34. See Documentation/trace/ftrace-design.txt
  35. config HAVE_FENTRY
  36. bool
  37. help
  38. Arch supports the gcc options -pg with -mfentry
  39. config HAVE_C_RECORDMCOUNT
  40. bool
  41. help
  42. C version of recordmcount available?
  43. config TRACER_MAX_TRACE
  44. bool
  45. config TRACE_CLOCK
  46. bool
  47. config RING_BUFFER
  48. bool
  49. select TRACE_CLOCK
  50. select IRQ_WORK
  51. config FTRACE_NMI_ENTER
  52. bool
  53. depends on HAVE_FTRACE_NMI_ENTER
  54. default y
  55. config EVENT_TRACING
  56. select CONTEXT_SWITCH_TRACER
  57. select GLOB
  58. bool
  59. config GPU_TRACEPOINTS
  60. bool
  61. config CONTEXT_SWITCH_TRACER
  62. bool
  63. config RING_BUFFER_ALLOW_SWAP
  64. bool
  65. help
  66. Allow the use of ring_buffer_swap_cpu.
  67. Adds a very slight overhead to tracing when enabled.
  68. # All tracer options should select GENERIC_TRACER. For those options that are
  69. # enabled by all tracers (context switch and event tracer) they select TRACING.
  70. # This allows those options to appear when no other tracer is selected. But the
  71. # options do not appear when something else selects it. We need the two options
  72. # GENERIC_TRACER and TRACING to avoid circular dependencies to accomplish the
  73. # hiding of the automatic options.
  74. config TRACING
  75. bool
  76. select RING_BUFFER
  77. select STACKTRACE if STACKTRACE_SUPPORT
  78. select TRACEPOINTS
  79. select NOP_TRACER
  80. select BINARY_PRINTF
  81. select EVENT_TRACING
  82. select TRACE_CLOCK
  83. config GENERIC_TRACER
  84. bool
  85. select TRACING
  86. #
  87. # Minimum requirements an architecture has to meet for us to
  88. # be able to offer generic tracing facilities:
  89. #
  90. config TRACING_SUPPORT
  91. bool
  92. # PPC32 has no irqflags tracing support, but it can use most of the
  93. # tracers anyway, they were tested to build and work. Note that new
  94. # exceptions to this list aren't welcomed, better implement the
  95. # irqflags tracing for your architecture.
  96. depends on TRACE_IRQFLAGS_SUPPORT || PPC32
  97. depends on STACKTRACE_SUPPORT
  98. default y
  99. if TRACING_SUPPORT
  100. menuconfig FTRACE
  101. bool "Tracers"
  102. default y if DEBUG_KERNEL
  103. help
  104. Enable the kernel tracing infrastructure.
  105. if FTRACE
  106. config FUNCTION_TRACER
  107. bool "Kernel Function Tracer"
  108. depends on HAVE_FUNCTION_TRACER
  109. select KALLSYMS
  110. select GENERIC_TRACER
  111. select CONTEXT_SWITCH_TRACER
  112. select GLOB
  113. select TASKS_RCU if PREEMPT
  114. help
  115. Enable the kernel to trace every kernel function. This is done
  116. by using a compiler feature to insert a small, 5-byte No-Operation
  117. instruction at the beginning of every kernel function, which NOP
  118. sequence is then dynamically patched into a tracer call when
  119. tracing is enabled by the administrator. If it's runtime disabled
  120. (the bootup default), then the overhead of the instructions is very
  121. small and not measurable even in micro-benchmarks.
  122. config FUNCTION_GRAPH_TRACER
  123. bool "Kernel Function Graph Tracer"
  124. depends on HAVE_FUNCTION_GRAPH_TRACER
  125. depends on FUNCTION_TRACER
  126. depends on !X86_32 || !CC_OPTIMIZE_FOR_SIZE
  127. default y
  128. help
  129. Enable the kernel to trace a function at both its return
  130. and its entry.
  131. Its first purpose is to trace the duration of functions and
  132. draw a call graph for each thread with some information like
  133. the return value. This is done by setting the current return
  134. address on the current task structure into a stack of calls.
  135. config PREEMPTIRQ_EVENTS
  136. bool "Enable trace events for preempt and irq disable/enable"
  137. select TRACE_IRQFLAGS
  138. depends on DEBUG_PREEMPT || !PROVE_LOCKING
  139. default n
  140. help
  141. Enable tracing of disable and enable events for preemption and irqs.
  142. For tracing preempt disable/enable events, DEBUG_PREEMPT must be
  143. enabled. For tracing irq disable/enable events, PROVE_LOCKING must
  144. be disabled.
  145. config IRQSOFF_TRACER
  146. bool "Interrupts-off Latency Tracer"
  147. default n
  148. depends on TRACE_IRQFLAGS_SUPPORT
  149. depends on !ARCH_USES_GETTIMEOFFSET
  150. select TRACE_IRQFLAGS
  151. select GENERIC_TRACER
  152. select TRACER_MAX_TRACE
  153. select RING_BUFFER_ALLOW_SWAP
  154. select TRACER_SNAPSHOT
  155. select TRACER_SNAPSHOT_PER_CPU_SWAP
  156. help
  157. This option measures the time spent in irqs-off critical
  158. sections, with microsecond accuracy.
  159. The default measurement method is a maximum search, which is
  160. disabled by default and can be runtime (re-)started
  161. via:
  162. echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
  163. (Note that kernel size and overhead increase with this option
  164. enabled. This option and the preempt-off timing option can be
  165. used together or separately.)
  166. config PREEMPT_TRACER
  167. bool "Preemption-off Latency Tracer"
  168. default n
  169. depends on !ARCH_USES_GETTIMEOFFSET
  170. depends on PREEMPT
  171. select GENERIC_TRACER
  172. select TRACER_MAX_TRACE
  173. select RING_BUFFER_ALLOW_SWAP
  174. select TRACER_SNAPSHOT
  175. select TRACER_SNAPSHOT_PER_CPU_SWAP
  176. help
  177. This option measures the time spent in preemption-off critical
  178. sections, with microsecond accuracy.
  179. The default measurement method is a maximum search, which is
  180. disabled by default and can be runtime (re-)started
  181. via:
  182. echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
  183. (Note that kernel size and overhead increase with this option
  184. enabled. This option and the irqs-off timing option can be
  185. used together or separately.)
  186. config SCHED_TRACER
  187. bool "Scheduling Latency Tracer"
  188. select GENERIC_TRACER
  189. select CONTEXT_SWITCH_TRACER
  190. select TRACER_MAX_TRACE
  191. select TRACER_SNAPSHOT
  192. help
  193. This tracer tracks the latency of the highest priority task
  194. to be scheduled in, starting from the point it has woken up.
  195. config HWLAT_TRACER
  196. bool "Tracer to detect hardware latencies (like SMIs)"
  197. select GENERIC_TRACER
  198. help
  199. This tracer, when enabled will create one or more kernel threads,
  200. depening on what the cpumask file is set to, which each thread
  201. spinning in a loop looking for interruptions caused by
  202. something other than the kernel. For example, if a
  203. System Management Interrupt (SMI) takes a noticeable amount of
  204. time, this tracer will detect it. This is useful for testing
  205. if a system is reliable for Real Time tasks.
  206. Some files are created in the tracing directory when this
  207. is enabled:
  208. hwlat_detector/width - time in usecs for how long to spin for
  209. hwlat_detector/window - time in usecs between the start of each
  210. iteration
  211. A kernel thread is created that will spin with interrupts disabled
  212. for "width" microseconds in every "widow" cycle. It will not spin
  213. for "window - width" microseconds, where the system can
  214. continue to operate.
  215. The output will appear in the trace and trace_pipe files.
  216. When the tracer is not running, it has no affect on the system,
  217. but when it is running, it can cause the system to be
  218. periodically non responsive. Do not run this tracer on a
  219. production system.
  220. To enable this tracer, echo in "hwlat" into the current_tracer
  221. file. Every time a latency is greater than tracing_thresh, it will
  222. be recorded into the ring buffer.
  223. config ENABLE_DEFAULT_TRACERS
  224. bool "Trace process context switches and events"
  225. depends on !GENERIC_TRACER
  226. select TRACING
  227. help
  228. This tracer hooks to various trace points in the kernel,
  229. allowing the user to pick and choose which trace point they
  230. want to trace. It also includes the sched_switch tracer plugin.
  231. config FTRACE_SYSCALLS
  232. bool "Trace syscalls"
  233. depends on HAVE_SYSCALL_TRACEPOINTS
  234. select GENERIC_TRACER
  235. select KALLSYMS
  236. help
  237. Basic tracer to catch the syscall entry and exit events.
  238. config TRACER_SNAPSHOT
  239. bool "Create a snapshot trace buffer"
  240. select TRACER_MAX_TRACE
  241. help
  242. Allow tracing users to take snapshot of the current buffer using the
  243. ftrace interface, e.g.:
  244. echo 1 > /sys/kernel/debug/tracing/snapshot
  245. cat snapshot
  246. config TRACER_SNAPSHOT_PER_CPU_SWAP
  247. bool "Allow snapshot to swap per CPU"
  248. depends on TRACER_SNAPSHOT
  249. select RING_BUFFER_ALLOW_SWAP
  250. help
  251. Allow doing a snapshot of a single CPU buffer instead of a
  252. full swap (all buffers). If this is set, then the following is
  253. allowed:
  254. echo 1 > /sys/kernel/debug/tracing/per_cpu/cpu2/snapshot
  255. After which, only the tracing buffer for CPU 2 was swapped with
  256. the main tracing buffer, and the other CPU buffers remain the same.
  257. When this is enabled, this adds a little more overhead to the
  258. trace recording, as it needs to add some checks to synchronize
  259. recording with swaps. But this does not affect the performance
  260. of the overall system. This is enabled by default when the preempt
  261. or irq latency tracers are enabled, as those need to swap as well
  262. and already adds the overhead (plus a lot more).
  263. config TRACE_BRANCH_PROFILING
  264. bool
  265. select GENERIC_TRACER
  266. choice
  267. prompt "Branch Profiling"
  268. default BRANCH_PROFILE_NONE
  269. help
  270. The branch profiling is a software profiler. It will add hooks
  271. into the C conditionals to test which path a branch takes.
  272. The likely/unlikely profiler only looks at the conditions that
  273. are annotated with a likely or unlikely macro.
  274. The "all branch" profiler will profile every if-statement in the
  275. kernel. This profiler will also enable the likely/unlikely
  276. profiler.
  277. Either of the above profilers adds a bit of overhead to the system.
  278. If unsure, choose "No branch profiling".
  279. config BRANCH_PROFILE_NONE
  280. bool "No branch profiling"
  281. help
  282. No branch profiling. Branch profiling adds a bit of overhead.
  283. Only enable it if you want to analyse the branching behavior.
  284. Otherwise keep it disabled.
  285. config PROFILE_ANNOTATED_BRANCHES
  286. bool "Trace likely/unlikely profiler"
  287. select TRACE_BRANCH_PROFILING
  288. help
  289. This tracer profiles all likely and unlikely macros
  290. in the kernel. It will display the results in:
  291. /sys/kernel/debug/tracing/trace_stat/branch_annotated
  292. Note: this will add a significant overhead; only turn this
  293. on if you need to profile the system's use of these macros.
  294. config PROFILE_ALL_BRANCHES
  295. bool "Profile all if conditionals" if !FORTIFY_SOURCE
  296. select TRACE_BRANCH_PROFILING
  297. help
  298. This tracer profiles all branch conditions. Every if ()
  299. taken in the kernel is recorded whether it hit or miss.
  300. The results will be displayed in:
  301. /sys/kernel/debug/tracing/trace_stat/branch_all
  302. This option also enables the likely/unlikely profiler.
  303. This configuration, when enabled, will impose a great overhead
  304. on the system. This should only be enabled when the system
  305. is to be analyzed in much detail.
  306. endchoice
  307. config TRACING_BRANCHES
  308. bool
  309. help
  310. Selected by tracers that will trace the likely and unlikely
  311. conditions. This prevents the tracers themselves from being
  312. profiled. Profiling the tracing infrastructure can only happen
  313. when the likelys and unlikelys are not being traced.
  314. config BRANCH_TRACER
  315. bool "Trace likely/unlikely instances"
  316. depends on TRACE_BRANCH_PROFILING
  317. select TRACING_BRANCHES
  318. help
  319. This traces the events of likely and unlikely condition
  320. calls in the kernel. The difference between this and the
  321. "Trace likely/unlikely profiler" is that this is not a
  322. histogram of the callers, but actually places the calling
  323. events into a running trace buffer to see when and where the
  324. events happened, as well as their results.
  325. Say N if unsure.
  326. config STACK_TRACER
  327. bool "Trace max stack"
  328. depends on HAVE_FUNCTION_TRACER
  329. select FUNCTION_TRACER
  330. select STACKTRACE
  331. select KALLSYMS
  332. help
  333. This special tracer records the maximum stack footprint of the
  334. kernel and displays it in /sys/kernel/debug/tracing/stack_trace.
  335. This tracer works by hooking into every function call that the
  336. kernel executes, and keeping a maximum stack depth value and
  337. stack-trace saved. If this is configured with DYNAMIC_FTRACE
  338. then it will not have any overhead while the stack tracer
  339. is disabled.
  340. To enable the stack tracer on bootup, pass in 'stacktrace'
  341. on the kernel command line.
  342. The stack tracer can also be enabled or disabled via the
  343. sysctl kernel.stack_tracer_enabled
  344. Say N if unsure.
  345. config BLK_DEV_IO_TRACE
  346. bool "Support for tracing block IO actions"
  347. depends on SYSFS
  348. depends on BLOCK
  349. select RELAY
  350. select DEBUG_FS
  351. select TRACEPOINTS
  352. select GENERIC_TRACER
  353. select STACKTRACE
  354. help
  355. Say Y here if you want to be able to trace the block layer actions
  356. on a given queue. Tracing allows you to see any traffic happening
  357. on a block device queue. For more information (and the userspace
  358. support tools needed), fetch the blktrace tools from:
  359. git://git.kernel.dk/blktrace.git
  360. Tracing also is possible using the ftrace interface, e.g.:
  361. echo 1 > /sys/block/sda/sda1/trace/enable
  362. echo blk > /sys/kernel/debug/tracing/current_tracer
  363. cat /sys/kernel/debug/tracing/trace_pipe
  364. If unsure, say N.
  365. config KPROBE_EVENTS
  366. depends on KPROBES
  367. depends on HAVE_REGS_AND_STACK_ACCESS_API
  368. bool "Enable kprobes-based dynamic events"
  369. select TRACING
  370. select PROBE_EVENTS
  371. default y
  372. help
  373. This allows the user to add tracing events (similar to tracepoints)
  374. on the fly via the ftrace interface. See
  375. Documentation/trace/kprobetrace.txt for more details.
  376. Those events can be inserted wherever kprobes can probe, and record
  377. various register and memory values.
  378. This option is also required by perf-probe subcommand of perf tools.
  379. If you want to use perf tools, this option is strongly recommended.
  380. config UPROBE_EVENTS
  381. bool "Enable uprobes-based dynamic events"
  382. depends on ARCH_SUPPORTS_UPROBES
  383. depends on MMU
  384. depends on PERF_EVENTS
  385. select UPROBES
  386. select PROBE_EVENTS
  387. select TRACING
  388. default y
  389. help
  390. This allows the user to add tracing events on top of userspace
  391. dynamic events (similar to tracepoints) on the fly via the trace
  392. events interface. Those events can be inserted wherever uprobes
  393. can probe, and record various registers.
  394. This option is required if you plan to use perf-probe subcommand
  395. of perf tools on user space applications.
  396. config BPF_EVENTS
  397. depends on BPF_SYSCALL
  398. depends on (KPROBE_EVENTS || UPROBE_EVENTS) && PERF_EVENTS
  399. bool
  400. default y
  401. help
  402. This allows the user to attach BPF programs to kprobe events.
  403. config PROBE_EVENTS
  404. def_bool n
  405. config DYNAMIC_FTRACE
  406. bool "enable/disable function tracing dynamically"
  407. depends on FUNCTION_TRACER
  408. depends on HAVE_DYNAMIC_FTRACE
  409. default y
  410. help
  411. This option will modify all the calls to function tracing
  412. dynamically (will patch them out of the binary image and
  413. replace them with a No-Op instruction) on boot up. During
  414. compile time, a table is made of all the locations that ftrace
  415. can function trace, and this table is linked into the kernel
  416. image. When this is enabled, functions can be individually
  417. enabled, and the functions not enabled will not affect
  418. performance of the system.
  419. See the files in /sys/kernel/debug/tracing:
  420. available_filter_functions
  421. set_ftrace_filter
  422. set_ftrace_notrace
  423. This way a CONFIG_FUNCTION_TRACER kernel is slightly larger, but
  424. otherwise has native performance as long as no tracing is active.
  425. config DYNAMIC_FTRACE_WITH_REGS
  426. def_bool y
  427. depends on DYNAMIC_FTRACE
  428. depends on HAVE_DYNAMIC_FTRACE_WITH_REGS
  429. config FUNCTION_PROFILER
  430. bool "Kernel function profiler"
  431. depends on FUNCTION_TRACER
  432. default n
  433. help
  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.
  440. If in doubt, say N.
  441. config FTRACE_MCOUNT_RECORD
  442. def_bool y
  443. depends on DYNAMIC_FTRACE
  444. depends on HAVE_FTRACE_MCOUNT_RECORD
  445. config FTRACE_SELFTEST
  446. bool
  447. config FTRACE_STARTUP_TEST
  448. bool "Perform a startup test on ftrace"
  449. depends on GENERIC_TRACER
  450. select FTRACE_SELFTEST
  451. help
  452. This option performs a series of startup tests on ftrace. On bootup
  453. a series of tests are made to verify that the tracer is
  454. functioning properly. It will do tests on all the configured
  455. tracers of ftrace.
  456. config EVENT_TRACE_TEST_SYSCALLS
  457. bool "Run selftest on syscall events"
  458. depends on FTRACE_STARTUP_TEST
  459. help
  460. This option will also enable testing every syscall event.
  461. It only enables the event and disables it and runs various loads
  462. with the event enabled. This adds a bit more time for kernel boot
  463. up since it runs this on every system call defined.
  464. TBD - enable a way to actually call the syscalls as we test their
  465. events
  466. config MMIOTRACE
  467. bool "Memory mapped IO tracing"
  468. depends on HAVE_MMIOTRACE_SUPPORT && PCI
  469. select GENERIC_TRACER
  470. help
  471. Mmiotrace traces Memory Mapped I/O access and is meant for
  472. debugging and reverse engineering. It is called from the ioremap
  473. implementation and works via page faults. Tracing is disabled by
  474. default and can be enabled at run-time.
  475. See Documentation/trace/mmiotrace.txt.
  476. If you are not helping to develop drivers, say N.
  477. config TRACING_MAP
  478. bool
  479. depends on ARCH_HAVE_NMI_SAFE_CMPXCHG
  480. help
  481. tracing_map is a special-purpose lock-free map for tracing,
  482. separated out as a stand-alone facility in order to allow it
  483. to be shared between multiple tracers. It isn't meant to be
  484. generally used outside of that context, and is normally
  485. selected by tracers that use it.
  486. config HIST_TRIGGERS
  487. bool "Histogram triggers"
  488. depends on ARCH_HAVE_NMI_SAFE_CMPXCHG
  489. select TRACING_MAP
  490. select TRACING
  491. default n
  492. help
  493. Hist triggers allow one or more arbitrary trace event fields
  494. to be aggregated into hash tables and dumped to stdout by
  495. reading a debugfs/tracefs file. They're useful for
  496. gathering quick and dirty (though precise) summaries of
  497. event activity as an initial guide for further investigation
  498. using more advanced tools.
  499. See Documentation/trace/events.txt.
  500. If in doubt, say N.
  501. config MMIOTRACE_TEST
  502. tristate "Test module for mmiotrace"
  503. depends on MMIOTRACE && m
  504. help
  505. This is a dumb module for testing mmiotrace. It is very dangerous
  506. as it will write garbage to IO memory starting at a given address.
  507. However, it should be safe to use on e.g. unused portion of VRAM.
  508. Say N, unless you absolutely know what you are doing.
  509. config TRACEPOINT_BENCHMARK
  510. bool "Add tracepoint that benchmarks tracepoints"
  511. help
  512. This option creates the tracepoint "benchmark:benchmark_event".
  513. When the tracepoint is enabled, it kicks off a kernel thread that
  514. goes into an infinite loop (calling cond_sched() to let other tasks
  515. run), and calls the tracepoint. Each iteration will record the time
  516. it took to write to the tracepoint and the next iteration that
  517. data will be passed to the tracepoint itself. That is, the tracepoint
  518. will report the time it took to do the previous tracepoint.
  519. The string written to the tracepoint is a static string of 128 bytes
  520. to keep the time the same. The initial string is simply a write of
  521. "START". The second string records the cold cache time of the first
  522. write which is not added to the rest of the calculations.
  523. As it is a tight loop, it benchmarks as hot cache. That's fine because
  524. we care most about hot paths that are probably in cache already.
  525. An example of the output:
  526. START
  527. first=3672 [COLD CACHED]
  528. last=632 first=3672 max=632 min=632 avg=316 std=446 std^2=199712
  529. last=278 first=3672 max=632 min=278 avg=303 std=316 std^2=100337
  530. last=277 first=3672 max=632 min=277 avg=296 std=258 std^2=67064
  531. last=273 first=3672 max=632 min=273 avg=292 std=224 std^2=50411
  532. last=273 first=3672 max=632 min=273 avg=288 std=200 std^2=40389
  533. last=281 first=3672 max=632 min=273 avg=287 std=183 std^2=33666
  534. config RING_BUFFER_BENCHMARK
  535. tristate "Ring buffer benchmark stress tester"
  536. depends on RING_BUFFER
  537. help
  538. This option creates a test to stress the ring buffer and benchmark it.
  539. It creates its own ring buffer such that it will not interfere with
  540. any other users of the ring buffer (such as ftrace). It then creates
  541. a producer and consumer that will run for 10 seconds and sleep for
  542. 10 seconds. Each interval it will print out the number of events
  543. it recorded and give a rough estimate of how long each iteration took.
  544. It does not disable interrupts or raise its priority, so it may be
  545. affected by processes that are running.
  546. If unsure, say N.
  547. config RING_BUFFER_STARTUP_TEST
  548. bool "Ring buffer startup self test"
  549. depends on RING_BUFFER
  550. help
  551. Run a simple self test on the ring buffer on boot up. Late in the
  552. kernel boot sequence, the test will start that kicks off
  553. a thread per cpu. Each thread will write various size events
  554. into the ring buffer. Another thread is created to send IPIs
  555. to each of the threads, where the IPI handler will also write
  556. to the ring buffer, to test/stress the nesting ability.
  557. If any anomalies are discovered, a warning will be displayed
  558. and all ring buffers will be disabled.
  559. The test runs for 10 seconds. This will slow your boot time
  560. by at least 10 more seconds.
  561. At the end of the test, statics and more checks are done.
  562. It will output the stats of each per cpu buffer. What
  563. was written, the sizes, what was read, what was lost, and
  564. other similar details.
  565. If unsure, say N
  566. config TRACE_EVAL_MAP_FILE
  567. bool "Show eval mappings for trace events"
  568. depends on TRACING
  569. help
  570. The "print fmt" of the trace events will show the enum/sizeof names
  571. instead of their values. This can cause problems for user space tools
  572. that use this string to parse the raw data as user space does not know
  573. how to convert the string to its value.
  574. To fix this, there's a special macro in the kernel that can be used
  575. to convert an enum/sizeof into its value. If this macro is used, then
  576. the print fmt strings will be converted to their values.
  577. If something does not get converted properly, this option can be
  578. used to show what enums/sizeof the kernel tried to convert.
  579. This option is for debugging the conversions. A file is created
  580. in the tracing directory called "eval_map" that will show the
  581. names matched with their values and what trace event system they
  582. belong too.
  583. Normally, the mapping of the strings to values will be freed after
  584. boot up or module load. With this option, they will not be freed, as
  585. they are needed for the "eval_map" file. Enabling this option will
  586. increase the memory footprint of the running kernel.
  587. If unsure, say N
  588. config TRACING_EVENTS_GPIO
  589. bool "Trace gpio events"
  590. depends on GPIOLIB
  591. default y
  592. help
  593. Enable tracing events for gpio subsystem
  594. endif # FTRACE
  595. endif # TRACING_SUPPORT
  596. if TRACING
  597. # MTK enhancements
  598. config MTK_SCHED_TRACERS
  599. bool "MTK Sched Tracers"
  600. select CONTEXT_SWITCH_TRACER
  601. help
  602. Mediatek enhancements to vanilla linux kernel. Include export task
  603. status and other information in sched_switch events, and track irq
  604. duration when irq is disabled / enabled.
  605. If unsure, say N
  606. config MTK_FTRACE_DEFAULT_ENABLE
  607. bool "enable MTK events by default"
  608. depends on MTK_SCHED_TRACERS
  609. help
  610. Enable ftrace at bootup e.g., enlarge ring_buffer size and enable
  611. configured events at bootup. With ftrace enabled and trace collected
  612. at exceptions, developers can better analyze the problem
  613. If unsure, say N
  614. config MTK_KERNEL_MARKER
  615. bool "MTK Kernel Marker API"
  616. depends on KALLSYMS
  617. help
  618. Export trace_marker in kernel space. Mark the user-defined points,
  619. such as systrace events in user space, to visualize via systrace html
  620. files
  621. If unsure, say N
  622. endif # TRACING