xref: /linux/kernel/trace/Kconfig (revision 45408c4f92506dbdfef1721f2613e1426de00894)
116444a8aSArnaldo Carvalho de Melo#
2606576ceSSteven Rostedt# Architectures that offer an FUNCTION_TRACER implementation should
3606576ceSSteven Rostedt#  select HAVE_FUNCTION_TRACER:
416444a8aSArnaldo Carvalho de Melo#
52a3a4f66SFrédéric Weisbecker
68d26487fSTörök Edwinconfig USER_STACKTRACE_SUPPORT
78d26487fSTörök Edwin	bool
88d26487fSTörök Edwin
92a3a4f66SFrédéric Weisbeckerconfig NOP_TRACER
102a3a4f66SFrédéric Weisbecker	bool
112a3a4f66SFrédéric Weisbecker
1278d904b4SSteven Rostedtconfig HAVE_FTRACE_NMI_ENTER
1378d904b4SSteven Rostedt	bool
14555f386cSMike Frysinger	help
155fb94e9cSMauro Carvalho Chehab	  See Documentation/trace/ftrace-design.rst
1678d904b4SSteven Rostedt
17606576ceSSteven Rostedtconfig HAVE_FUNCTION_TRACER
1816444a8aSArnaldo Carvalho de Melo	bool
19555f386cSMike Frysinger	help
205fb94e9cSMauro Carvalho Chehab	  See Documentation/trace/ftrace-design.rst
21bc0c38d1SSteven Rostedt
22fb52607aSFrederic Weisbeckerconfig HAVE_FUNCTION_GRAPH_TRACER
2315e6cb36SFrederic Weisbecker	bool
24555f386cSMike Frysinger	help
255fb94e9cSMauro Carvalho Chehab	  See Documentation/trace/ftrace-design.rst
2615e6cb36SFrederic Weisbecker
27677aa9f7SSteven Rostedtconfig HAVE_DYNAMIC_FTRACE
28677aa9f7SSteven Rostedt	bool
29555f386cSMike Frysinger	help
305fb94e9cSMauro Carvalho Chehab	  See Documentation/trace/ftrace-design.rst
31677aa9f7SSteven Rostedt
3206aeaaeaSMasami Hiramatsuconfig HAVE_DYNAMIC_FTRACE_WITH_REGS
3306aeaaeaSMasami Hiramatsu	bool
3406aeaaeaSMasami Hiramatsu
358da3821bSSteven Rostedtconfig HAVE_FTRACE_MCOUNT_RECORD
368da3821bSSteven Rostedt	bool
37555f386cSMike Frysinger	help
385fb94e9cSMauro Carvalho Chehab	  See Documentation/trace/ftrace-design.rst
398da3821bSSteven Rostedt
4066700001SJosh Stoneconfig HAVE_SYSCALL_TRACEPOINTS
41ee08c6ecSFrederic Weisbecker	bool
42555f386cSMike Frysinger	help
435fb94e9cSMauro Carvalho Chehab	  See Documentation/trace/ftrace-design.rst
44ee08c6ecSFrederic Weisbecker
45a2546faeSSteven Rostedtconfig HAVE_FENTRY
46a2546faeSSteven Rostedt	bool
47a2546faeSSteven Rostedt	help
48a2546faeSSteven Rostedt	  Arch supports the gcc options -pg with -mfentry
49a2546faeSSteven Rostedt
50cf4db259SSteven Rostedtconfig HAVE_C_RECORDMCOUNT
5172441cb1SSteven Rostedt	bool
5272441cb1SSteven Rostedt	help
5372441cb1SSteven Rostedt	  C version of recordmcount available?
5472441cb1SSteven Rostedt
55352ad25aSSteven Rostedtconfig TRACER_MAX_TRACE
56352ad25aSSteven Rostedt	bool
57352ad25aSSteven Rostedt
58ea632e9fSJosh Triplettconfig TRACE_CLOCK
59ea632e9fSJosh Triplett	bool
60ea632e9fSJosh Triplett
617a8e76a3SSteven Rostedtconfig RING_BUFFER
627a8e76a3SSteven Rostedt	bool
63ea632e9fSJosh Triplett	select TRACE_CLOCK
6422287688SSteven Rostedt (Red Hat)	select IRQ_WORK
657a8e76a3SSteven Rostedt
6678d904b4SSteven Rostedtconfig FTRACE_NMI_ENTER
6778d904b4SSteven Rostedt       bool
6878d904b4SSteven Rostedt       depends on HAVE_FTRACE_NMI_ENTER
6978d904b4SSteven Rostedt       default y
7078d904b4SSteven Rostedt
715f77a88bSTom Zanussiconfig EVENT_TRACING
72b11c53e1SZhaolei	select CONTEXT_SWITCH_TRACER
7360f1d5e3SMasami Hiramatsu        select GLOB
74b11c53e1SZhaolei	bool
75b11c53e1SZhaolei
76b11c53e1SZhaoleiconfig CONTEXT_SWITCH_TRACER
775f77a88bSTom Zanussi	bool
785f77a88bSTom Zanussi
7985bac32cSSteven Rostedtconfig RING_BUFFER_ALLOW_SWAP
8085bac32cSSteven Rostedt	bool
8185bac32cSSteven Rostedt	help
8285bac32cSSteven Rostedt	 Allow the use of ring_buffer_swap_cpu.
8385bac32cSSteven Rostedt	 Adds a very slight overhead to tracing when enabled.
8485bac32cSSteven Rostedt
855e0a0939SSteven Rostedt# All tracer options should select GENERIC_TRACER. For those options that are
865e0a0939SSteven Rostedt# enabled by all tracers (context switch and event tracer) they select TRACING.
875e0a0939SSteven Rostedt# This allows those options to appear when no other tracer is selected. But the
885e0a0939SSteven Rostedt# options do not appear when something else selects it. We need the two options
895e0a0939SSteven Rostedt# GENERIC_TRACER and TRACING to avoid circular dependencies to accomplish the
9040892367SRandy Dunlap# hiding of the automatic options.
915e0a0939SSteven Rostedt
92bc0c38d1SSteven Rostedtconfig TRACING
93bc0c38d1SSteven Rostedt	bool
94bc0c38d1SSteven Rostedt	select DEBUG_FS
957a8e76a3SSteven Rostedt	select RING_BUFFER
96c2c80529SAl Viro	select STACKTRACE if STACKTRACE_SUPPORT
975f87f112SIngo Molnar	select TRACEPOINTS
98f3384b28SSteven Rostedt	select NOP_TRACER
99769b0441SFrederic Weisbecker	select BINARY_PRINTF
1005f77a88bSTom Zanussi	select EVENT_TRACING
101ea632e9fSJosh Triplett	select TRACE_CLOCK
102bc0c38d1SSteven Rostedt
1035e0a0939SSteven Rostedtconfig GENERIC_TRACER
1045e0a0939SSteven Rostedt	bool
1055e0a0939SSteven Rostedt	select TRACING
1065e0a0939SSteven Rostedt
10740ada30fSIngo Molnar#
10840ada30fSIngo Molnar# Minimum requirements an architecture has to meet for us to
10940ada30fSIngo Molnar# be able to offer generic tracing facilities:
11040ada30fSIngo Molnar#
11140ada30fSIngo Molnarconfig TRACING_SUPPORT
11240ada30fSIngo Molnar	bool
1130ea5ee03SMichael Ellerman	depends on TRACE_IRQFLAGS_SUPPORT
11440ada30fSIngo Molnar	depends on STACKTRACE_SUPPORT
115422d3c7aSKOSAKI Motohiro	default y
11640ada30fSIngo Molnar
11740ada30fSIngo Molnarif TRACING_SUPPORT
11840ada30fSIngo Molnar
1194ed9f071SSteven Rostedtmenuconfig FTRACE
1204ed9f071SSteven Rostedt	bool "Tracers"
12165b77242SSteven Rostedt	default y if DEBUG_KERNEL
1224ed9f071SSteven Rostedt	help
1234ed9f071SSteven Rostedt	  Enable the kernel tracing infrastructure.
1244ed9f071SSteven Rostedt
1254ed9f071SSteven Rostedtif FTRACE
12617d80fd0SPeter Zijlstra
127606576ceSSteven Rostedtconfig FUNCTION_TRACER
1281b29b018SSteven Rostedt	bool "Kernel Function Tracer"
129606576ceSSteven Rostedt	depends on HAVE_FUNCTION_TRACER
1304d7a077cSSteven Rostedt	select KALLSYMS
1315e0a0939SSteven Rostedt	select GENERIC_TRACER
13235e8e302SSteven Rostedt	select CONTEXT_SWITCH_TRACER
13360f1d5e3SMasami Hiramatsu	select GLOB
1340598e4f0SSteven Rostedt (VMware)	select TASKS_RCU if PREEMPT
1351b29b018SSteven Rostedt	help
1361b29b018SSteven Rostedt	  Enable the kernel to trace every kernel function. This is done
1371b29b018SSteven Rostedt	  by using a compiler feature to insert a small, 5-byte No-Operation
13840892367SRandy Dunlap	  instruction at the beginning of every kernel function, which NOP
1391b29b018SSteven Rostedt	  sequence is then dynamically patched into a tracer call when
1401b29b018SSteven Rostedt	  tracing is enabled by the administrator. If it's runtime disabled
1411b29b018SSteven Rostedt	  (the bootup default), then the overhead of the instructions is very
1421b29b018SSteven Rostedt	  small and not measurable even in micro-benchmarks.
14335e8e302SSteven Rostedt
144fb52607aSFrederic Weisbeckerconfig FUNCTION_GRAPH_TRACER
145fb52607aSFrederic Weisbecker	bool "Kernel Function Graph Tracer"
146fb52607aSFrederic Weisbecker	depends on HAVE_FUNCTION_GRAPH_TRACER
14715e6cb36SFrederic Weisbecker	depends on FUNCTION_TRACER
148eb4a0378SSteven Rostedt	depends on !X86_32 || !CC_OPTIMIZE_FOR_SIZE
149764f3b95SIngo Molnar	default y
15015e6cb36SFrederic Weisbecker	help
151fb52607aSFrederic Weisbecker	  Enable the kernel to trace a function at both its return
152fb52607aSFrederic Weisbecker	  and its entry.
153692105b8SMatt LaPlante	  Its first purpose is to trace the duration of functions and
154692105b8SMatt LaPlante	  draw a call graph for each thread with some information like
155692105b8SMatt LaPlante	  the return value. This is done by setting the current return
156692105b8SMatt LaPlante	  address on the current task structure into a stack of calls.
15715e6cb36SFrederic Weisbecker
158bac429f0SSteven Rostedt
159d5915816SJoel Fernandesconfig PREEMPTIRQ_EVENTS
160d5915816SJoel Fernandes	bool "Enable trace events for preempt and irq disable/enable"
161d5915816SJoel Fernandes	select TRACE_IRQFLAGS
162d5915816SJoel Fernandes	depends on DEBUG_PREEMPT || !PROVE_LOCKING
1632dde6b00SArnd Bergmann	depends on TRACING
164d5915816SJoel Fernandes	default n
165d5915816SJoel Fernandes	help
166d5915816SJoel Fernandes	  Enable tracing of disable and enable events for preemption and irqs.
167d5915816SJoel Fernandes	  For tracing preempt disable/enable events, DEBUG_PREEMPT must be
168d5915816SJoel Fernandes	  enabled. For tracing irq disable/enable events, PROVE_LOCKING must
169d5915816SJoel Fernandes	  be disabled.
170d5915816SJoel Fernandes
17181d68a96SSteven Rostedtconfig IRQSOFF_TRACER
17281d68a96SSteven Rostedt	bool "Interrupts-off Latency Tracer"
17381d68a96SSteven Rostedt	default n
17481d68a96SSteven Rostedt	depends on TRACE_IRQFLAGS_SUPPORT
175592913ecSJohn Stultz	depends on !ARCH_USES_GETTIMEOFFSET
17681d68a96SSteven Rostedt	select TRACE_IRQFLAGS
1775e0a0939SSteven Rostedt	select GENERIC_TRACER
17881d68a96SSteven Rostedt	select TRACER_MAX_TRACE
17985bac32cSSteven Rostedt	select RING_BUFFER_ALLOW_SWAP
18022cffc2bSSteven Rostedt (Red Hat)	select TRACER_SNAPSHOT
1810b85ffc2SSteven Rostedt (Red Hat)	select TRACER_SNAPSHOT_PER_CPU_SWAP
18281d68a96SSteven Rostedt	help
18381d68a96SSteven Rostedt	  This option measures the time spent in irqs-off critical
18481d68a96SSteven Rostedt	  sections, with microsecond accuracy.
18581d68a96SSteven Rostedt
18681d68a96SSteven Rostedt	  The default measurement method is a maximum search, which is
18781d68a96SSteven Rostedt	  disabled by default and can be runtime (re-)started
18881d68a96SSteven Rostedt	  via:
18981d68a96SSteven Rostedt
190156f5a78SGeunSik Lim	      echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
19181d68a96SSteven Rostedt
19240892367SRandy Dunlap	  (Note that kernel size and overhead increase with this option
1936cd8a4bbSSteven Rostedt	  enabled. This option and the preempt-off timing option can be
1946cd8a4bbSSteven Rostedt	  used together or separately.)
1956cd8a4bbSSteven Rostedt
1966cd8a4bbSSteven Rostedtconfig PREEMPT_TRACER
1976cd8a4bbSSteven Rostedt	bool "Preemption-off Latency Tracer"
1986cd8a4bbSSteven Rostedt	default n
199592913ecSJohn Stultz	depends on !ARCH_USES_GETTIMEOFFSET
2006cd8a4bbSSteven Rostedt	depends on PREEMPT
2015e0a0939SSteven Rostedt	select GENERIC_TRACER
2026cd8a4bbSSteven Rostedt	select TRACER_MAX_TRACE
20385bac32cSSteven Rostedt	select RING_BUFFER_ALLOW_SWAP
20422cffc2bSSteven Rostedt (Red Hat)	select TRACER_SNAPSHOT
2050b85ffc2SSteven Rostedt (Red Hat)	select TRACER_SNAPSHOT_PER_CPU_SWAP
2066cd8a4bbSSteven Rostedt	help
20740892367SRandy Dunlap	  This option measures the time spent in preemption-off critical
2086cd8a4bbSSteven Rostedt	  sections, with microsecond accuracy.
2096cd8a4bbSSteven Rostedt
2106cd8a4bbSSteven Rostedt	  The default measurement method is a maximum search, which is
2116cd8a4bbSSteven Rostedt	  disabled by default and can be runtime (re-)started
2126cd8a4bbSSteven Rostedt	  via:
2136cd8a4bbSSteven Rostedt
214156f5a78SGeunSik Lim	      echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
2156cd8a4bbSSteven Rostedt
21640892367SRandy Dunlap	  (Note that kernel size and overhead increase with this option
2176cd8a4bbSSteven Rostedt	  enabled. This option and the irqs-off timing option can be
2186cd8a4bbSSteven Rostedt	  used together or separately.)
2196cd8a4bbSSteven Rostedt
220352ad25aSSteven Rostedtconfig SCHED_TRACER
221352ad25aSSteven Rostedt	bool "Scheduling Latency Tracer"
2225e0a0939SSteven Rostedt	select GENERIC_TRACER
223352ad25aSSteven Rostedt	select CONTEXT_SWITCH_TRACER
224352ad25aSSteven Rostedt	select TRACER_MAX_TRACE
22522cffc2bSSteven Rostedt (Red Hat)	select TRACER_SNAPSHOT
226352ad25aSSteven Rostedt	help
227352ad25aSSteven Rostedt	  This tracer tracks the latency of the highest priority task
228352ad25aSSteven Rostedt	  to be scheduled in, starting from the point it has woken up.
229352ad25aSSteven Rostedt
230e7c15cd8SSteven Rostedt (Red Hat)config HWLAT_TRACER
231e7c15cd8SSteven Rostedt (Red Hat)	bool "Tracer to detect hardware latencies (like SMIs)"
232e7c15cd8SSteven Rostedt (Red Hat)	select GENERIC_TRACER
233e7c15cd8SSteven Rostedt (Red Hat)	help
234e7c15cd8SSteven Rostedt (Red Hat)	 This tracer, when enabled will create one or more kernel threads,
235c5c1ea75SJesper Dangaard Brouer	 depending on what the cpumask file is set to, which each thread
236e7c15cd8SSteven Rostedt (Red Hat)	 spinning in a loop looking for interruptions caused by
237e7c15cd8SSteven Rostedt (Red Hat)	 something other than the kernel. For example, if a
238e7c15cd8SSteven Rostedt (Red Hat)	 System Management Interrupt (SMI) takes a noticeable amount of
239e7c15cd8SSteven Rostedt (Red Hat)	 time, this tracer will detect it. This is useful for testing
240e7c15cd8SSteven Rostedt (Red Hat)	 if a system is reliable for Real Time tasks.
241e7c15cd8SSteven Rostedt (Red Hat)
242e7c15cd8SSteven Rostedt (Red Hat)	 Some files are created in the tracing directory when this
243e7c15cd8SSteven Rostedt (Red Hat)	 is enabled:
244e7c15cd8SSteven Rostedt (Red Hat)
245e7c15cd8SSteven Rostedt (Red Hat)	   hwlat_detector/width   - time in usecs for how long to spin for
246e7c15cd8SSteven Rostedt (Red Hat)	   hwlat_detector/window  - time in usecs between the start of each
247e7c15cd8SSteven Rostedt (Red Hat)				     iteration
248e7c15cd8SSteven Rostedt (Red Hat)
249e7c15cd8SSteven Rostedt (Red Hat)	 A kernel thread is created that will spin with interrupts disabled
250c5c1ea75SJesper Dangaard Brouer	 for "width" microseconds in every "window" cycle. It will not spin
251e7c15cd8SSteven Rostedt (Red Hat)	 for "window - width" microseconds, where the system can
252e7c15cd8SSteven Rostedt (Red Hat)	 continue to operate.
253e7c15cd8SSteven Rostedt (Red Hat)
254e7c15cd8SSteven Rostedt (Red Hat)	 The output will appear in the trace and trace_pipe files.
255e7c15cd8SSteven Rostedt (Red Hat)
256e7c15cd8SSteven Rostedt (Red Hat)	 When the tracer is not running, it has no affect on the system,
257e7c15cd8SSteven Rostedt (Red Hat)	 but when it is running, it can cause the system to be
258e7c15cd8SSteven Rostedt (Red Hat)	 periodically non responsive. Do not run this tracer on a
259e7c15cd8SSteven Rostedt (Red Hat)	 production system.
260e7c15cd8SSteven Rostedt (Red Hat)
261e7c15cd8SSteven Rostedt (Red Hat)	 To enable this tracer, echo in "hwlat" into the current_tracer
262e7c15cd8SSteven Rostedt (Red Hat)	 file. Every time a latency is greater than tracing_thresh, it will
263e7c15cd8SSteven Rostedt (Red Hat)	 be recorded into the ring buffer.
264e7c15cd8SSteven Rostedt (Red Hat)
265897f17a6SSteven Rostedtconfig ENABLE_DEFAULT_TRACERS
266897f17a6SSteven Rostedt	bool "Trace process context switches and events"
2675e0a0939SSteven Rostedt	depends on !GENERIC_TRACER
268b77e38aaSSteven Rostedt	select TRACING
269b77e38aaSSteven Rostedt	help
27040892367SRandy Dunlap	  This tracer hooks to various trace points in the kernel,
271b77e38aaSSteven Rostedt	  allowing the user to pick and choose which trace point they
272897f17a6SSteven Rostedt	  want to trace. It also includes the sched_switch tracer plugin.
273a7abe97fSSteven Rostedt
274ee08c6ecSFrederic Weisbeckerconfig FTRACE_SYSCALLS
275ee08c6ecSFrederic Weisbecker	bool "Trace syscalls"
27666700001SJosh Stone	depends on HAVE_SYSCALL_TRACEPOINTS
2775e0a0939SSteven Rostedt	select GENERIC_TRACER
2780ea1c415SFrederic Weisbecker	select KALLSYMS
279ee08c6ecSFrederic Weisbecker	help
280ee08c6ecSFrederic Weisbecker	  Basic tracer to catch the syscall entry and exit events.
281ee08c6ecSFrederic Weisbecker
282debdd57fSHiraku Toyookaconfig TRACER_SNAPSHOT
283debdd57fSHiraku Toyooka	bool "Create a snapshot trace buffer"
284debdd57fSHiraku Toyooka	select TRACER_MAX_TRACE
285debdd57fSHiraku Toyooka	help
286debdd57fSHiraku Toyooka	  Allow tracing users to take snapshot of the current buffer using the
287debdd57fSHiraku Toyooka	  ftrace interface, e.g.:
288debdd57fSHiraku Toyooka
289debdd57fSHiraku Toyooka	      echo 1 > /sys/kernel/debug/tracing/snapshot
290debdd57fSHiraku Toyooka	      cat snapshot
291debdd57fSHiraku Toyooka
2920b85ffc2SSteven Rostedt (Red Hat)config TRACER_SNAPSHOT_PER_CPU_SWAP
2930b85ffc2SSteven Rostedt (Red Hat)        bool "Allow snapshot to swap per CPU"
2940b85ffc2SSteven Rostedt (Red Hat)	depends on TRACER_SNAPSHOT
2950b85ffc2SSteven Rostedt (Red Hat)	select RING_BUFFER_ALLOW_SWAP
2960b85ffc2SSteven Rostedt (Red Hat)	help
2970b85ffc2SSteven Rostedt (Red Hat)	  Allow doing a snapshot of a single CPU buffer instead of a
2980b85ffc2SSteven Rostedt (Red Hat)	  full swap (all buffers). If this is set, then the following is
2990b85ffc2SSteven Rostedt (Red Hat)	  allowed:
3000b85ffc2SSteven Rostedt (Red Hat)
3010b85ffc2SSteven Rostedt (Red Hat)	      echo 1 > /sys/kernel/debug/tracing/per_cpu/cpu2/snapshot
3020b85ffc2SSteven Rostedt (Red Hat)
3030b85ffc2SSteven Rostedt (Red Hat)	  After which, only the tracing buffer for CPU 2 was swapped with
3040b85ffc2SSteven Rostedt (Red Hat)	  the main tracing buffer, and the other CPU buffers remain the same.
3050b85ffc2SSteven Rostedt (Red Hat)
3060b85ffc2SSteven Rostedt (Red Hat)	  When this is enabled, this adds a little more overhead to the
3070b85ffc2SSteven Rostedt (Red Hat)	  trace recording, as it needs to add some checks to synchronize
3080b85ffc2SSteven Rostedt (Red Hat)	  recording with swaps. But this does not affect the performance
3090b85ffc2SSteven Rostedt (Red Hat)	  of the overall system. This is enabled by default when the preempt
3100b85ffc2SSteven Rostedt (Red Hat)	  or irq latency tracers are enabled, as those need to swap as well
3110b85ffc2SSteven Rostedt (Red Hat)	  and already adds the overhead (plus a lot more).
3120b85ffc2SSteven Rostedt (Red Hat)
3132ed84eebSSteven Rostedtconfig TRACE_BRANCH_PROFILING
3149ae5b879SSteven Rostedt	bool
3155e0a0939SSteven Rostedt	select GENERIC_TRACER
3169ae5b879SSteven Rostedt
3179ae5b879SSteven Rostedtchoice
3189ae5b879SSteven Rostedt	prompt "Branch Profiling"
3199ae5b879SSteven Rostedt	default BRANCH_PROFILE_NONE
3209ae5b879SSteven Rostedt	help
3219ae5b879SSteven Rostedt	 The branch profiling is a software profiler. It will add hooks
3229ae5b879SSteven Rostedt	 into the C conditionals to test which path a branch takes.
3239ae5b879SSteven Rostedt
3249ae5b879SSteven Rostedt	 The likely/unlikely profiler only looks at the conditions that
3259ae5b879SSteven Rostedt	 are annotated with a likely or unlikely macro.
3269ae5b879SSteven Rostedt
32740892367SRandy Dunlap	 The "all branch" profiler will profile every if-statement in the
3289ae5b879SSteven Rostedt	 kernel. This profiler will also enable the likely/unlikely
32940892367SRandy Dunlap	 profiler.
3309ae5b879SSteven Rostedt
33140892367SRandy Dunlap	 Either of the above profilers adds a bit of overhead to the system.
33240892367SRandy Dunlap	 If unsure, choose "No branch profiling".
3339ae5b879SSteven Rostedt
3349ae5b879SSteven Rostedtconfig BRANCH_PROFILE_NONE
3359ae5b879SSteven Rostedt	bool "No branch profiling"
3369ae5b879SSteven Rostedt	help
3379ae5b879SSteven Rostedt	  No branch profiling. Branch profiling adds a bit of overhead.
3389ae5b879SSteven Rostedt	  Only enable it if you want to analyse the branching behavior.
3399ae5b879SSteven Rostedt	  Otherwise keep it disabled.
3409ae5b879SSteven Rostedt
3419ae5b879SSteven Rostedtconfig PROFILE_ANNOTATED_BRANCHES
3429ae5b879SSteven Rostedt	bool "Trace likely/unlikely profiler"
3439ae5b879SSteven Rostedt	select TRACE_BRANCH_PROFILING
3441f0d69a9SSteven Rostedt	help
34559bf8964SMasanari Iida	  This tracer profiles all likely and unlikely macros
3461f0d69a9SSteven Rostedt	  in the kernel. It will display the results in:
3471f0d69a9SSteven Rostedt
34813e5befaSDavid Rientjes	  /sys/kernel/debug/tracing/trace_stat/branch_annotated
3491f0d69a9SSteven Rostedt
35040892367SRandy Dunlap	  Note: this will add a significant overhead; only turn this
3511f0d69a9SSteven Rostedt	  on if you need to profile the system's use of these macros.
3521f0d69a9SSteven Rostedt
3532bcd521aSSteven Rostedtconfig PROFILE_ALL_BRANCHES
35468e76e03SRandy Dunlap	bool "Profile all if conditionals" if !FORTIFY_SOURCE
3559ae5b879SSteven Rostedt	select TRACE_BRANCH_PROFILING
3562bcd521aSSteven Rostedt	help
3572bcd521aSSteven Rostedt	  This tracer profiles all branch conditions. Every if ()
3582bcd521aSSteven Rostedt	  taken in the kernel is recorded whether it hit or miss.
3592bcd521aSSteven Rostedt	  The results will be displayed in:
3602bcd521aSSteven Rostedt
36113e5befaSDavid Rientjes	  /sys/kernel/debug/tracing/trace_stat/branch_all
3622bcd521aSSteven Rostedt
3639ae5b879SSteven Rostedt	  This option also enables the likely/unlikely profiler.
3649ae5b879SSteven Rostedt
3652bcd521aSSteven Rostedt	  This configuration, when enabled, will impose a great overhead
3662bcd521aSSteven Rostedt	  on the system. This should only be enabled when the system
36740892367SRandy Dunlap	  is to be analyzed in much detail.
3689ae5b879SSteven Rostedtendchoice
3692bcd521aSSteven Rostedt
3702ed84eebSSteven Rostedtconfig TRACING_BRANCHES
37152f232cbSSteven Rostedt	bool
37252f232cbSSteven Rostedt	help
37352f232cbSSteven Rostedt	  Selected by tracers that will trace the likely and unlikely
37452f232cbSSteven Rostedt	  conditions. This prevents the tracers themselves from being
37552f232cbSSteven Rostedt	  profiled. Profiling the tracing infrastructure can only happen
37652f232cbSSteven Rostedt	  when the likelys and unlikelys are not being traced.
37752f232cbSSteven Rostedt
3782ed84eebSSteven Rostedtconfig BRANCH_TRACER
37952f232cbSSteven Rostedt	bool "Trace likely/unlikely instances"
3802ed84eebSSteven Rostedt	depends on TRACE_BRANCH_PROFILING
3812ed84eebSSteven Rostedt	select TRACING_BRANCHES
38252f232cbSSteven Rostedt	help
38352f232cbSSteven Rostedt	  This traces the events of likely and unlikely condition
38452f232cbSSteven Rostedt	  calls in the kernel.  The difference between this and the
38552f232cbSSteven Rostedt	  "Trace likely/unlikely profiler" is that this is not a
38652f232cbSSteven Rostedt	  histogram of the callers, but actually places the calling
38752f232cbSSteven Rostedt	  events into a running trace buffer to see when and where the
38852f232cbSSteven Rostedt	  events happened, as well as their results.
38952f232cbSSteven Rostedt
39052f232cbSSteven Rostedt	  Say N if unsure.
39152f232cbSSteven Rostedt
392e5a81b62SSteven Rostedtconfig STACK_TRACER
393e5a81b62SSteven Rostedt	bool "Trace max stack"
394606576ceSSteven Rostedt	depends on HAVE_FUNCTION_TRACER
395606576ceSSteven Rostedt	select FUNCTION_TRACER
396e5a81b62SSteven Rostedt	select STACKTRACE
3974d7a077cSSteven Rostedt	select KALLSYMS
398e5a81b62SSteven Rostedt	help
3994519d9e5SIngo Molnar	  This special tracer records the maximum stack footprint of the
400156f5a78SGeunSik Lim	  kernel and displays it in /sys/kernel/debug/tracing/stack_trace.
4014519d9e5SIngo Molnar
4024519d9e5SIngo Molnar	  This tracer works by hooking into every function call that the
4034519d9e5SIngo Molnar	  kernel executes, and keeping a maximum stack depth value and
404f38f1d2aSSteven Rostedt	  stack-trace saved.  If this is configured with DYNAMIC_FTRACE
405f38f1d2aSSteven Rostedt	  then it will not have any overhead while the stack tracer
406f38f1d2aSSteven Rostedt	  is disabled.
407f38f1d2aSSteven Rostedt
408f38f1d2aSSteven Rostedt	  To enable the stack tracer on bootup, pass in 'stacktrace'
409f38f1d2aSSteven Rostedt	  on the kernel command line.
410f38f1d2aSSteven Rostedt
411f38f1d2aSSteven Rostedt	  The stack tracer can also be enabled or disabled via the
412f38f1d2aSSteven Rostedt	  sysctl kernel.stack_tracer_enabled
4134519d9e5SIngo Molnar
4144519d9e5SIngo Molnar	  Say N if unsure.
415e5a81b62SSteven Rostedt
4162db270a8SFrederic Weisbeckerconfig BLK_DEV_IO_TRACE
41740892367SRandy Dunlap	bool "Support for tracing block IO actions"
4182db270a8SFrederic Weisbecker	depends on SYSFS
4191dfba05dSIngo Molnar	depends on BLOCK
4202db270a8SFrederic Weisbecker	select RELAY
4212db270a8SFrederic Weisbecker	select DEBUG_FS
4222db270a8SFrederic Weisbecker	select TRACEPOINTS
4235e0a0939SSteven Rostedt	select GENERIC_TRACER
4242db270a8SFrederic Weisbecker	select STACKTRACE
4252db270a8SFrederic Weisbecker	help
4262db270a8SFrederic Weisbecker	  Say Y here if you want to be able to trace the block layer actions
4272db270a8SFrederic Weisbecker	  on a given queue. Tracing allows you to see any traffic happening
4282db270a8SFrederic Weisbecker	  on a block device queue. For more information (and the userspace
4292db270a8SFrederic Weisbecker	  support tools needed), fetch the blktrace tools from:
4302db270a8SFrederic Weisbecker
4312db270a8SFrederic Weisbecker	  git://git.kernel.dk/blktrace.git
4322db270a8SFrederic Weisbecker
4332db270a8SFrederic Weisbecker	  Tracing also is possible using the ftrace interface, e.g.:
4342db270a8SFrederic Weisbecker
4352db270a8SFrederic Weisbecker	    echo 1 > /sys/block/sda/sda1/trace/enable
4362db270a8SFrederic Weisbecker	    echo blk > /sys/kernel/debug/tracing/current_tracer
4372db270a8SFrederic Weisbecker	    cat /sys/kernel/debug/tracing/trace_pipe
4382db270a8SFrederic Weisbecker
4392db270a8SFrederic Weisbecker	  If unsure, say N.
44036994e58SFrederic Weisbecker
4416b0b7551SAnton Blanchardconfig KPROBE_EVENTS
442413d37d1SMasami Hiramatsu	depends on KPROBES
443f850c30cSHeiko Carstens	depends on HAVE_REGS_AND_STACK_ACCESS_API
44477b44d1bSMasami Hiramatsu	bool "Enable kprobes-based dynamic events"
445413d37d1SMasami Hiramatsu	select TRACING
4468ab83f56SSrikar Dronamraju	select PROBE_EVENTS
44777b44d1bSMasami Hiramatsu	default y
448413d37d1SMasami Hiramatsu	help
44940892367SRandy Dunlap	  This allows the user to add tracing events (similar to tracepoints)
45040892367SRandy Dunlap	  on the fly via the ftrace interface. See
4515fb94e9cSMauro Carvalho Chehab	  Documentation/trace/kprobetrace.rst for more details.
45277b44d1bSMasami Hiramatsu
45377b44d1bSMasami Hiramatsu	  Those events can be inserted wherever kprobes can probe, and record
45477b44d1bSMasami Hiramatsu	  various register and memory values.
45577b44d1bSMasami Hiramatsu
45640892367SRandy Dunlap	  This option is also required by perf-probe subcommand of perf tools.
45740892367SRandy Dunlap	  If you want to use perf tools, this option is strongly recommended.
458413d37d1SMasami Hiramatsu
459*45408c4fSMasami Hiramatsuconfig KPROBE_EVENTS_ON_NOTRACE
460*45408c4fSMasami Hiramatsu	bool "Do NOT protect notrace function from kprobe events"
461*45408c4fSMasami Hiramatsu	depends on KPROBE_EVENTS
462*45408c4fSMasami Hiramatsu	depends on KPROBES_ON_FTRACE
463*45408c4fSMasami Hiramatsu	default n
464*45408c4fSMasami Hiramatsu	help
465*45408c4fSMasami Hiramatsu	  This is only for the developers who want to debug ftrace itself
466*45408c4fSMasami Hiramatsu	  using kprobe events.
467*45408c4fSMasami Hiramatsu
468*45408c4fSMasami Hiramatsu	  If kprobes can use ftrace instead of breakpoint, ftrace related
469*45408c4fSMasami Hiramatsu	  functions are protected from kprobe-events to prevent an infinit
470*45408c4fSMasami Hiramatsu	  recursion or any unexpected execution path which leads to a kernel
471*45408c4fSMasami Hiramatsu	  crash.
472*45408c4fSMasami Hiramatsu
473*45408c4fSMasami Hiramatsu	  This option disables such protection and allows you to put kprobe
474*45408c4fSMasami Hiramatsu	  events on ftrace functions for debugging ftrace by itself.
475*45408c4fSMasami Hiramatsu	  Note that this might let you shoot yourself in the foot.
476*45408c4fSMasami Hiramatsu
477*45408c4fSMasami Hiramatsu	  If unsure, say N.
478*45408c4fSMasami Hiramatsu
4796b0b7551SAnton Blanchardconfig UPROBE_EVENTS
480f3f096cfSSrikar Dronamraju	bool "Enable uprobes-based dynamic events"
481f3f096cfSSrikar Dronamraju	depends on ARCH_SUPPORTS_UPROBES
482f3f096cfSSrikar Dronamraju	depends on MMU
48309294e31SDavid A. Long	depends on PERF_EVENTS
484f3f096cfSSrikar Dronamraju	select UPROBES
485f3f096cfSSrikar Dronamraju	select PROBE_EVENTS
486f3f096cfSSrikar Dronamraju	select TRACING
48761f35d75SArnaldo Carvalho de Melo	default y
488f3f096cfSSrikar Dronamraju	help
489f3f096cfSSrikar Dronamraju	  This allows the user to add tracing events on top of userspace
490f3f096cfSSrikar Dronamraju	  dynamic events (similar to tracepoints) on the fly via the trace
491f3f096cfSSrikar Dronamraju	  events interface. Those events can be inserted wherever uprobes
492f3f096cfSSrikar Dronamraju	  can probe, and record various registers.
493f3f096cfSSrikar Dronamraju	  This option is required if you plan to use perf-probe subcommand
494f3f096cfSSrikar Dronamraju	  of perf tools on user space applications.
495f3f096cfSSrikar Dronamraju
496e1abf2ccSIngo Molnarconfig BPF_EVENTS
497e1abf2ccSIngo Molnar	depends on BPF_SYSCALL
4986b0b7551SAnton Blanchard	depends on (KPROBE_EVENTS || UPROBE_EVENTS) && PERF_EVENTS
499e1abf2ccSIngo Molnar	bool
500e1abf2ccSIngo Molnar	default y
501e1abf2ccSIngo Molnar	help
502e1abf2ccSIngo Molnar	  This allows the user to attach BPF programs to kprobe events.
503e1abf2ccSIngo Molnar
5048ab83f56SSrikar Dronamrajuconfig PROBE_EVENTS
5058ab83f56SSrikar Dronamraju	def_bool n
5068ab83f56SSrikar Dronamraju
5073d083395SSteven Rostedtconfig DYNAMIC_FTRACE
508db05021dSSteven Rostedt	bool "enable/disable function tracing dynamically"
509606576ceSSteven Rostedt	depends on FUNCTION_TRACER
510677aa9f7SSteven Rostedt	depends on HAVE_DYNAMIC_FTRACE
5113d083395SSteven Rostedt	default y
5123d083395SSteven Rostedt	help
513db05021dSSteven Rostedt	  This option will modify all the calls to function tracing
514db05021dSSteven Rostedt	  dynamically (will patch them out of the binary image and
515db05021dSSteven Rostedt	  replace them with a No-Op instruction) on boot up. During
516db05021dSSteven Rostedt	  compile time, a table is made of all the locations that ftrace
517db05021dSSteven Rostedt	  can function trace, and this table is linked into the kernel
518db05021dSSteven Rostedt	  image. When this is enabled, functions can be individually
519db05021dSSteven Rostedt	  enabled, and the functions not enabled will not affect
520db05021dSSteven Rostedt	  performance of the system.
521db05021dSSteven Rostedt
522db05021dSSteven Rostedt	  See the files in /sys/kernel/debug/tracing:
523db05021dSSteven Rostedt	    available_filter_functions
524db05021dSSteven Rostedt	    set_ftrace_filter
525db05021dSSteven Rostedt	    set_ftrace_notrace
5263d083395SSteven Rostedt
52740892367SRandy Dunlap	  This way a CONFIG_FUNCTION_TRACER kernel is slightly larger, but
52840892367SRandy Dunlap	  otherwise has native performance as long as no tracing is active.
5293d083395SSteven Rostedt
53006aeaaeaSMasami Hiramatsuconfig DYNAMIC_FTRACE_WITH_REGS
53106aeaaeaSMasami Hiramatsu	def_bool y
53206aeaaeaSMasami Hiramatsu	depends on DYNAMIC_FTRACE
53306aeaaeaSMasami Hiramatsu	depends on HAVE_DYNAMIC_FTRACE_WITH_REGS
53406aeaaeaSMasami Hiramatsu
535bac429f0SSteven Rostedtconfig FUNCTION_PROFILER
536bac429f0SSteven Rostedt	bool "Kernel function profiler"
537493762fcSSteven Rostedt	depends on FUNCTION_TRACER
538bac429f0SSteven Rostedt	default n
539bac429f0SSteven Rostedt	help
540493762fcSSteven Rostedt	  This option enables the kernel function profiler. A file is created
541493762fcSSteven Rostedt	  in debugfs called function_profile_enabled which defaults to zero.
542bac429f0SSteven Rostedt	  When a 1 is echoed into this file profiling begins, and when a
54340892367SRandy Dunlap	  zero is entered, profiling stops. A "functions" file is created in
54440892367SRandy Dunlap	  the trace_stats directory; this file shows the list of functions that
545bac429f0SSteven Rostedt	  have been hit and their counters.
546bac429f0SSteven Rostedt
54740892367SRandy Dunlap	  If in doubt, say N.
548bac429f0SSteven Rostedt
5499802d865SJosef Bacikconfig BPF_KPROBE_OVERRIDE
5509802d865SJosef Bacik	bool "Enable BPF programs to override a kprobed function"
5519802d865SJosef Bacik	depends on BPF_EVENTS
552540adea3SMasami Hiramatsu	depends on FUNCTION_ERROR_INJECTION
5539802d865SJosef Bacik	default n
5549802d865SJosef Bacik	help
5559802d865SJosef Bacik	 Allows BPF to override the execution of a probed function and
5569802d865SJosef Bacik	 set a different return value.  This is used for error injection.
5579802d865SJosef Bacik
5588da3821bSSteven Rostedtconfig FTRACE_MCOUNT_RECORD
5598da3821bSSteven Rostedt	def_bool y
5608da3821bSSteven Rostedt	depends on DYNAMIC_FTRACE
5618da3821bSSteven Rostedt	depends on HAVE_FTRACE_MCOUNT_RECORD
5628da3821bSSteven Rostedt
56360a11774SSteven Rostedtconfig FTRACE_SELFTEST
56460a11774SSteven Rostedt	bool
56560a11774SSteven Rostedt
56660a11774SSteven Rostedtconfig FTRACE_STARTUP_TEST
56760a11774SSteven Rostedt	bool "Perform a startup test on ftrace"
5685e0a0939SSteven Rostedt	depends on GENERIC_TRACER
56960a11774SSteven Rostedt	select FTRACE_SELFTEST
57060a11774SSteven Rostedt	help
57160a11774SSteven Rostedt	  This option performs a series of startup tests on ftrace. On bootup
57260a11774SSteven Rostedt	  a series of tests are made to verify that the tracer is
57360a11774SSteven Rostedt	  functioning properly. It will do tests on all the configured
57460a11774SSteven Rostedt	  tracers of ftrace.
57517d80fd0SPeter Zijlstra
5761f5a6b45SSteven Rostedtconfig EVENT_TRACE_TEST_SYSCALLS
5771f5a6b45SSteven Rostedt	bool "Run selftest on syscall events"
5781f5a6b45SSteven Rostedt	depends on FTRACE_STARTUP_TEST
5791f5a6b45SSteven Rostedt	help
5801f5a6b45SSteven Rostedt	 This option will also enable testing every syscall event.
5811f5a6b45SSteven Rostedt	 It only enables the event and disables it and runs various loads
5821f5a6b45SSteven Rostedt	 with the event enabled. This adds a bit more time for kernel boot
5831f5a6b45SSteven Rostedt	 up since it runs this on every system call defined.
5841f5a6b45SSteven Rostedt
5851f5a6b45SSteven Rostedt	 TBD - enable a way to actually call the syscalls as we test their
5861f5a6b45SSteven Rostedt	       events
5871f5a6b45SSteven Rostedt
588fe6f90e5SPekka Paalanenconfig MMIOTRACE
589fe6f90e5SPekka Paalanen	bool "Memory mapped IO tracing"
59040ada30fSIngo Molnar	depends on HAVE_MMIOTRACE_SUPPORT && PCI
5915e0a0939SSteven Rostedt	select GENERIC_TRACER
592fe6f90e5SPekka Paalanen	help
593fe6f90e5SPekka Paalanen	  Mmiotrace traces Memory Mapped I/O access and is meant for
594fe6f90e5SPekka Paalanen	  debugging and reverse engineering. It is called from the ioremap
595fe6f90e5SPekka Paalanen	  implementation and works via page faults. Tracing is disabled by
596fe6f90e5SPekka Paalanen	  default and can be enabled at run-time.
597fe6f90e5SPekka Paalanen
5985fb94e9cSMauro Carvalho Chehab	  See Documentation/trace/mmiotrace.rst.
599fe6f90e5SPekka Paalanen	  If you are not helping to develop drivers, say N.
600fe6f90e5SPekka Paalanen
60108d43a5fSTom Zanussiconfig TRACING_MAP
60208d43a5fSTom Zanussi	bool
60308d43a5fSTom Zanussi	depends on ARCH_HAVE_NMI_SAFE_CMPXCHG
60408d43a5fSTom Zanussi	help
60508d43a5fSTom Zanussi	  tracing_map is a special-purpose lock-free map for tracing,
60608d43a5fSTom Zanussi	  separated out as a stand-alone facility in order to allow it
60708d43a5fSTom Zanussi	  to be shared between multiple tracers.  It isn't meant to be
60808d43a5fSTom Zanussi	  generally used outside of that context, and is normally
60908d43a5fSTom Zanussi	  selected by tracers that use it.
61008d43a5fSTom Zanussi
6117ef224d1STom Zanussiconfig HIST_TRIGGERS
6127ef224d1STom Zanussi	bool "Histogram triggers"
6137ef224d1STom Zanussi	depends on ARCH_HAVE_NMI_SAFE_CMPXCHG
6147ef224d1STom Zanussi	select TRACING_MAP
6157ad8fb61STom Zanussi	select TRACING
6167ef224d1STom Zanussi	default n
6177ef224d1STom Zanussi	help
6187ef224d1STom Zanussi	  Hist triggers allow one or more arbitrary trace event fields
6197ef224d1STom Zanussi	  to be aggregated into hash tables and dumped to stdout by
6207ef224d1STom Zanussi	  reading a debugfs/tracefs file.  They're useful for
6217ef224d1STom Zanussi	  gathering quick and dirty (though precise) summaries of
6227ef224d1STom Zanussi	  event activity as an initial guide for further investigation
6237ef224d1STom Zanussi	  using more advanced tools.
6247ef224d1STom Zanussi
62589e270c1STom Zanussi	  Inter-event tracing of quantities such as latencies is also
62689e270c1STom Zanussi	  supported using hist triggers under this option.
62789e270c1STom Zanussi
62889e270c1STom Zanussi	  See Documentation/trace/histogram.txt.
6297ef224d1STom Zanussi	  If in doubt, say N.
6307ef224d1STom Zanussi
631fe6f90e5SPekka Paalanenconfig MMIOTRACE_TEST
632fe6f90e5SPekka Paalanen	tristate "Test module for mmiotrace"
633fe6f90e5SPekka Paalanen	depends on MMIOTRACE && m
634fe6f90e5SPekka Paalanen	help
635fe6f90e5SPekka Paalanen	  This is a dumb module for testing mmiotrace. It is very dangerous
636fe6f90e5SPekka Paalanen	  as it will write garbage to IO memory starting at a given address.
637fe6f90e5SPekka Paalanen	  However, it should be safe to use on e.g. unused portion of VRAM.
638fe6f90e5SPekka Paalanen
639fe6f90e5SPekka Paalanen	  Say N, unless you absolutely know what you are doing.
640fe6f90e5SPekka Paalanen
64181dc9f0eSSteven Rostedt (Red Hat)config TRACEPOINT_BENCHMARK
64281dc9f0eSSteven Rostedt (Red Hat)        bool "Add tracepoint that benchmarks tracepoints"
64381dc9f0eSSteven Rostedt (Red Hat)	help
64481dc9f0eSSteven Rostedt (Red Hat)	 This option creates the tracepoint "benchmark:benchmark_event".
64581dc9f0eSSteven Rostedt (Red Hat)	 When the tracepoint is enabled, it kicks off a kernel thread that
64681dc9f0eSSteven Rostedt (Red Hat)	 goes into an infinite loop (calling cond_sched() to let other tasks
64781dc9f0eSSteven Rostedt (Red Hat)	 run), and calls the tracepoint. Each iteration will record the time
64881dc9f0eSSteven Rostedt (Red Hat)	 it took to write to the tracepoint and the next iteration that
64981dc9f0eSSteven Rostedt (Red Hat)	 data will be passed to the tracepoint itself. That is, the tracepoint
65081dc9f0eSSteven Rostedt (Red Hat)	 will report the time it took to do the previous tracepoint.
65181dc9f0eSSteven Rostedt (Red Hat)	 The string written to the tracepoint is a static string of 128 bytes
65281dc9f0eSSteven Rostedt (Red Hat)	 to keep the time the same. The initial string is simply a write of
65381dc9f0eSSteven Rostedt (Red Hat)	 "START". The second string records the cold cache time of the first
65481dc9f0eSSteven Rostedt (Red Hat)	 write which is not added to the rest of the calculations.
65581dc9f0eSSteven Rostedt (Red Hat)
65681dc9f0eSSteven Rostedt (Red Hat)	 As it is a tight loop, it benchmarks as hot cache. That's fine because
65781dc9f0eSSteven Rostedt (Red Hat)	 we care most about hot paths that are probably in cache already.
65881dc9f0eSSteven Rostedt (Red Hat)
65981dc9f0eSSteven Rostedt (Red Hat)	 An example of the output:
66081dc9f0eSSteven Rostedt (Red Hat)
66181dc9f0eSSteven Rostedt (Red Hat)	      START
66281dc9f0eSSteven Rostedt (Red Hat)	      first=3672 [COLD CACHED]
66381dc9f0eSSteven Rostedt (Red Hat)	      last=632 first=3672 max=632 min=632 avg=316 std=446 std^2=199712
66481dc9f0eSSteven Rostedt (Red Hat)	      last=278 first=3672 max=632 min=278 avg=303 std=316 std^2=100337
66581dc9f0eSSteven Rostedt (Red Hat)	      last=277 first=3672 max=632 min=277 avg=296 std=258 std^2=67064
66681dc9f0eSSteven Rostedt (Red Hat)	      last=273 first=3672 max=632 min=273 avg=292 std=224 std^2=50411
66781dc9f0eSSteven Rostedt (Red Hat)	      last=273 first=3672 max=632 min=273 avg=288 std=200 std^2=40389
66881dc9f0eSSteven Rostedt (Red Hat)	      last=281 first=3672 max=632 min=273 avg=287 std=183 std^2=33666
66981dc9f0eSSteven Rostedt (Red Hat)
67081dc9f0eSSteven Rostedt (Red Hat)
6715092dbc9SSteven Rostedtconfig RING_BUFFER_BENCHMARK
6725092dbc9SSteven Rostedt	tristate "Ring buffer benchmark stress tester"
6735092dbc9SSteven Rostedt	depends on RING_BUFFER
6745092dbc9SSteven Rostedt	help
6755092dbc9SSteven Rostedt	  This option creates a test to stress the ring buffer and benchmark it.
67640892367SRandy Dunlap	  It creates its own ring buffer such that it will not interfere with
6775092dbc9SSteven Rostedt	  any other users of the ring buffer (such as ftrace). It then creates
6785092dbc9SSteven Rostedt	  a producer and consumer that will run for 10 seconds and sleep for
6795092dbc9SSteven Rostedt	  10 seconds. Each interval it will print out the number of events
6805092dbc9SSteven Rostedt	  it recorded and give a rough estimate of how long each iteration took.
6815092dbc9SSteven Rostedt
6825092dbc9SSteven Rostedt	  It does not disable interrupts or raise its priority, so it may be
6835092dbc9SSteven Rostedt	  affected by processes that are running.
6845092dbc9SSteven Rostedt
68540892367SRandy Dunlap	  If unsure, say N.
6865092dbc9SSteven Rostedt
6876c43e554SSteven Rostedt (Red Hat)config RING_BUFFER_STARTUP_TEST
6886c43e554SSteven Rostedt (Red Hat)       bool "Ring buffer startup self test"
6896c43e554SSteven Rostedt (Red Hat)       depends on RING_BUFFER
6906c43e554SSteven Rostedt (Red Hat)       help
6916c43e554SSteven Rostedt (Red Hat)         Run a simple self test on the ring buffer on boot up. Late in the
6926c43e554SSteven Rostedt (Red Hat)	 kernel boot sequence, the test will start that kicks off
6936c43e554SSteven Rostedt (Red Hat)	 a thread per cpu. Each thread will write various size events
6946c43e554SSteven Rostedt (Red Hat)	 into the ring buffer. Another thread is created to send IPIs
6956c43e554SSteven Rostedt (Red Hat)	 to each of the threads, where the IPI handler will also write
6966c43e554SSteven Rostedt (Red Hat)	 to the ring buffer, to test/stress the nesting ability.
6976c43e554SSteven Rostedt (Red Hat)	 If any anomalies are discovered, a warning will be displayed
6986c43e554SSteven Rostedt (Red Hat)	 and all ring buffers will be disabled.
6996c43e554SSteven Rostedt (Red Hat)
7006c43e554SSteven Rostedt (Red Hat)	 The test runs for 10 seconds. This will slow your boot time
7016c43e554SSteven Rostedt (Red Hat)	 by at least 10 more seconds.
7026c43e554SSteven Rostedt (Red Hat)
7036c43e554SSteven Rostedt (Red Hat)	 At the end of the test, statics and more checks are done.
7046c43e554SSteven Rostedt (Red Hat)	 It will output the stats of each per cpu buffer. What
7056c43e554SSteven Rostedt (Red Hat)	 was written, the sizes, what was read, what was lost, and
7066c43e554SSteven Rostedt (Red Hat)	 other similar details.
7076c43e554SSteven Rostedt (Red Hat)
7086c43e554SSteven Rostedt (Red Hat)	 If unsure, say N
7096c43e554SSteven Rostedt (Red Hat)
710f96e8577SJoel Fernandes (Google)config PREEMPTIRQ_DELAY_TEST
711f96e8577SJoel Fernandes (Google)	tristate "Preempt / IRQ disable delay thread to test latency tracers"
712f96e8577SJoel Fernandes (Google)	depends on m
713f96e8577SJoel Fernandes (Google)	help
714f96e8577SJoel Fernandes (Google)	  Select this option to build a test module that can help test latency
715f96e8577SJoel Fernandes (Google)	  tracers by executing a preempt or irq disable section with a user
716f96e8577SJoel Fernandes (Google)	  configurable delay. The module busy waits for the duration of the
717f96e8577SJoel Fernandes (Google)	  critical section.
718f96e8577SJoel Fernandes (Google)
719f96e8577SJoel Fernandes (Google)	  For example, the following invocation forces a one-time irq-disabled
720f96e8577SJoel Fernandes (Google)	  critical section for 500us:
721f96e8577SJoel Fernandes (Google)	  modprobe preemptirq_delay_test test_mode=irq delay=500000
722f96e8577SJoel Fernandes (Google)
723f96e8577SJoel Fernandes (Google)	  If unsure, say N
724f96e8577SJoel Fernandes (Google)
725681bec03SJeremy Lintonconfig TRACE_EVAL_MAP_FILE
726681bec03SJeremy Linton       bool "Show eval mappings for trace events"
7279828413dSSteven Rostedt (Red Hat)       depends on TRACING
7289828413dSSteven Rostedt (Red Hat)       help
729681bec03SJeremy Linton	The "print fmt" of the trace events will show the enum/sizeof names
730681bec03SJeremy Linton	instead	of their values. This can cause problems for user space tools
731681bec03SJeremy Linton	that use this string to parse the raw data as user space does not know
7329828413dSSteven Rostedt (Red Hat)	how to convert the string to its value.
7339828413dSSteven Rostedt (Red Hat)
7349828413dSSteven Rostedt (Red Hat)	To fix this, there's a special macro in the kernel that can be used
735681bec03SJeremy Linton	to convert an enum/sizeof into its value. If this macro is used, then
736681bec03SJeremy Linton	the print fmt strings will be converted to their values.
7379828413dSSteven Rostedt (Red Hat)
7389828413dSSteven Rostedt (Red Hat)	If something does not get converted properly, this option can be
739681bec03SJeremy Linton	used to show what enums/sizeof the kernel tried to convert.
7409828413dSSteven Rostedt (Red Hat)
741681bec03SJeremy Linton	This option is for debugging the conversions. A file is created
742681bec03SJeremy Linton	in the tracing directory called "eval_map" that will show the
7439828413dSSteven Rostedt (Red Hat)	names matched with their values and what trace event system they
7449828413dSSteven Rostedt (Red Hat)	belong too.
7459828413dSSteven Rostedt (Red Hat)
7469828413dSSteven Rostedt (Red Hat)	Normally, the mapping of the strings to values will be freed after
7479828413dSSteven Rostedt (Red Hat)	boot up or module load. With this option, they will not be freed, as
748681bec03SJeremy Linton	they are needed for the "eval_map" file. Enabling this option will
7499828413dSSteven Rostedt (Red Hat)	increase the memory footprint of the running kernel.
7509828413dSSteven Rostedt (Red Hat)
7519828413dSSteven Rostedt (Red Hat)	If unsure, say N
7529828413dSSteven Rostedt (Red Hat)
753ddd70280STal Shorerconfig TRACING_EVENTS_GPIO
754ddd70280STal Shorer	bool "Trace gpio events"
755ddd70280STal Shorer	depends on GPIOLIB
756ddd70280STal Shorer	default y
757ddd70280STal Shorer	help
758ddd70280STal Shorer	  Enable tracing events for gpio subsystem
759ddd70280STal Shorer
7604ed9f071SSteven Rostedtendif # FTRACE
76140ada30fSIngo Molnar
76240ada30fSIngo Molnarendif # TRACING_SUPPORT
76340ada30fSIngo Molnar
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