# select HAVE_FUNCTION_TRACER:
#
+config USER_STACKTRACE_SUPPORT
+ bool
+
config NOP_TRACER
bool
+config HAVE_FTRACE_NMI_ENTER
+ bool
+
config HAVE_FUNCTION_TRACER
bool
- select NOP_TRACER
+
+config HAVE_FUNCTION_GRAPH_TRACER
+ bool
+
+config HAVE_FUNCTION_TRACE_MCOUNT_TEST
+ bool
+ help
+ This gets selected when the arch tests the function_trace_stop
+ variable at the mcount call site. Otherwise, this variable
+ is tested by the called function.
config HAVE_DYNAMIC_FTRACE
bool
config HAVE_FTRACE_MCOUNT_RECORD
bool
+config HAVE_HW_BRANCH_TRACER
+ bool
+
+config HAVE_FTRACE_SYSCALLS
+ bool
+
config TRACER_MAX_TRACE
bool
config RING_BUFFER
bool
+config FTRACE_NMI_ENTER
+ bool
+ depends on HAVE_FTRACE_NMI_ENTER
+ default y
+
+config EVENT_TRACING
+ bool
+
config TRACING
bool
select DEBUG_FS
select RING_BUFFER
- select STACKTRACE
+ select STACKTRACE if STACKTRACE_SUPPORT
select TRACEPOINTS
+ select NOP_TRACER
+ select BINARY_PRINTF
+ select EVENT_TRACING
+
+#
+# Minimum requirements an architecture has to meet for us to
+# be able to offer generic tracing facilities:
+#
+config TRACING_SUPPORT
+ bool
+ # PPC32 has no irqflags tracing support, but it can use most of the
+ # tracers anyway, they were tested to build and work. Note that new
+ # exceptions to this list aren't welcomed, better implement the
+ # irqflags tracing for your architecture.
+ depends on TRACE_IRQFLAGS_SUPPORT || PPC32
+ depends on STACKTRACE_SUPPORT
+ default y
+
+if TRACING_SUPPORT
menu "Tracers"
config FUNCTION_TRACER
bool "Kernel Function Tracer"
depends on HAVE_FUNCTION_TRACER
- depends on DEBUG_KERNEL
select FRAME_POINTER
+ select KALLSYMS
select TRACING
select CONTEXT_SWITCH_TRACER
help
(the bootup default), then the overhead of the instructions is very
small and not measurable even in micro-benchmarks.
+config FUNCTION_GRAPH_TRACER
+ bool "Kernel Function Graph Tracer"
+ depends on HAVE_FUNCTION_GRAPH_TRACER
+ depends on FUNCTION_TRACER
+ default y
+ help
+ Enable the kernel to trace a function at both its return
+ and its entry.
+ Its first purpose is to trace the duration of functions and
+ draw a call graph for each thread with some information like
+ the return value. This is done by setting the current return
+ address on the current task structure into a stack of calls.
+
+
config IRQSOFF_TRACER
bool "Interrupts-off Latency Tracer"
default n
depends on TRACE_IRQFLAGS_SUPPORT
depends on GENERIC_TIME
- depends on DEBUG_KERNEL
select TRACE_IRQFLAGS
select TRACING
select TRACER_MAX_TRACE
default n
depends on GENERIC_TIME
depends on PREEMPT
- depends on DEBUG_KERNEL
select TRACING
select TRACER_MAX_TRACE
help
bool "Sysprof Tracer"
depends on X86
select TRACING
+ select CONTEXT_SWITCH_TRACER
help
This tracer provides the trace needed by the 'Sysprof' userspace
tool.
config SCHED_TRACER
bool "Scheduling Latency Tracer"
- depends on DEBUG_KERNEL
select TRACING
select CONTEXT_SWITCH_TRACER
select TRACER_MAX_TRACE
config CONTEXT_SWITCH_TRACER
bool "Trace process context switches"
- depends on DEBUG_KERNEL
select TRACING
select MARKERS
help
This tracer gets called from the context switch and records
all switching of tasks.
+config EVENT_TRACER
+ bool "Trace various events in the kernel"
+ select TRACING
+ help
+ This tracer hooks to various trace points in the kernel
+ allowing the user to pick and choose which trace point they
+ want to trace.
+
+config FTRACE_SYSCALLS
+ bool "Trace syscalls"
+ depends on HAVE_FTRACE_SYSCALLS
+ select TRACING
+ select KALLSYMS
+ help
+ Basic tracer to catch the syscall entry and exit events.
+
config BOOT_TRACER
bool "Trace boot initcalls"
- depends on DEBUG_KERNEL
select TRACING
select CONTEXT_SWITCH_TRACER
help
representation of the delays during initcalls - but the raw
/debug/tracing/trace text output is readable too.
- ( Note that tracing self tests can't be enabled if this tracer is
- selected, because the self-tests are an initcall as well and that
- would invalidate the boot trace. )
+ You must pass in ftrace=initcall to the kernel command line
+ to enable this on bootup.
+
+config TRACE_BRANCH_PROFILING
+ bool "Trace likely/unlikely profiler"
+ select TRACING
+ help
+ This tracer profiles all the the likely and unlikely macros
+ in the kernel. It will display the results in:
+
+ /debugfs/tracing/profile_annotated_branch
+
+ Note: this will add a significant overhead, only turn this
+ on if you need to profile the system's use of these macros.
+
+ Say N if unsure.
+
+config PROFILE_ALL_BRANCHES
+ bool "Profile all if conditionals"
+ depends on TRACE_BRANCH_PROFILING
+ help
+ This tracer profiles all branch conditions. Every if ()
+ taken in the kernel is recorded whether it hit or miss.
+ The results will be displayed in:
+
+ /debugfs/tracing/profile_branch
+
+ This configuration, when enabled, will impose a great overhead
+ on the system. This should only be enabled when the system
+ is to be analyzed
+
+ Say N if unsure.
+
+config TRACING_BRANCHES
+ bool
+ help
+ Selected by tracers that will trace the likely and unlikely
+ conditions. This prevents the tracers themselves from being
+ profiled. Profiling the tracing infrastructure can only happen
+ when the likelys and unlikelys are not being traced.
+
+config BRANCH_TRACER
+ bool "Trace likely/unlikely instances"
+ depends on TRACE_BRANCH_PROFILING
+ select TRACING_BRANCHES
+ help
+ This traces the events of likely and unlikely condition
+ calls in the kernel. The difference between this and the
+ "Trace likely/unlikely profiler" is that this is not a
+ histogram of the callers, but actually places the calling
+ events into a running trace buffer to see when and where the
+ events happened, as well as their results.
+
+ Say N if unsure.
+
+config POWER_TRACER
+ bool "Trace power consumption behavior"
+ depends on X86
+ select TRACING
+ help
+ This tracer helps developers to analyze and optimize the kernels
+ power management decisions, specifically the C-state and P-state
+ behavior.
+
config STACK_TRACER
bool "Trace max stack"
depends on HAVE_FUNCTION_TRACER
- depends on DEBUG_KERNEL
select FUNCTION_TRACER
select STACKTRACE
+ select KALLSYMS
help
This special tracer records the maximum stack footprint of the
kernel and displays it in debugfs/tracing/stack_trace.
This tracer works by hooking into every function call that the
kernel executes, and keeping a maximum stack depth value and
- stack-trace saved. Because this logic has to execute in every
- kernel function, all the time, this option can slow down the
- kernel measurably and is generally intended for kernel
- developers only.
+ stack-trace saved. If this is configured with DYNAMIC_FTRACE
+ then it will not have any overhead while the stack tracer
+ is disabled.
+
+ To enable the stack tracer on bootup, pass in 'stacktrace'
+ on the kernel command line.
+
+ The stack tracer can also be enabled or disabled via the
+ sysctl kernel.stack_tracer_enabled
Say N if unsure.
+config HW_BRANCH_TRACER
+ depends on HAVE_HW_BRANCH_TRACER
+ bool "Trace hw branches"
+ select TRACING
+ help
+ This tracer records all branches on the system in a circular
+ buffer giving access to the last N branches for each cpu.
+
+config KMEMTRACE
+ bool "Trace SLAB allocations"
+ select TRACING
+ help
+ kmemtrace provides tracing for slab allocator functions, such as
+ kmalloc, kfree, kmem_cache_alloc, kmem_cache_free etc.. Collected
+ data is then fed to the userspace application in order to analyse
+ allocation hotspots, internal fragmentation and so on, making it
+ possible to see how well an allocator performs, as well as debug
+ and profile kernel code.
+
+ This requires an userspace application to use. See
+ Documentation/trace/kmemtrace.txt for more information.
+
+ Saying Y will make the kernel somewhat larger and slower. However,
+ if you disable kmemtrace at run-time or boot-time, the performance
+ impact is minimal (depending on the arch the kernel is built for).
+
+ If unsure, say N.
+
+config WORKQUEUE_TRACER
+ bool "Trace workqueues"
+ select TRACING
+ help
+ The workqueue tracer provides some statistical informations
+ about each cpu workqueue thread such as the number of the
+ works inserted and executed since their creation. It can help
+ to evaluate the amount of work each of them have to perform.
+ For example it can help a developer to decide whether he should
+ choose a per cpu workqueue instead of a singlethreaded one.
+
+config BLK_DEV_IO_TRACE
+ bool "Support for tracing block io actions"
+ depends on SYSFS
+ depends on BLOCK
+ select RELAY
+ select DEBUG_FS
+ select TRACEPOINTS
+ select TRACING
+ select STACKTRACE
+ help
+ Say Y here if you want to be able to trace the block layer actions
+ on a given queue. Tracing allows you to see any traffic happening
+ on a block device queue. For more information (and the userspace
+ support tools needed), fetch the blktrace tools from:
+
+ git://git.kernel.dk/blktrace.git
+
+ Tracing also is possible using the ftrace interface, e.g.:
+
+ echo 1 > /sys/block/sda/sda1/trace/enable
+ echo blk > /sys/kernel/debug/tracing/current_tracer
+ cat /sys/kernel/debug/tracing/trace_pipe
+
+ If unsure, say N.
+
config DYNAMIC_FTRACE
bool "enable/disable ftrace tracepoints dynamically"
depends on FUNCTION_TRACER
depends on HAVE_DYNAMIC_FTRACE
- depends on DEBUG_KERNEL
default y
help
This option will modify all the calls to ftrace dynamically
were made. If so, it runs stop_machine (stops all CPUS)
and modifies the code to jump over the call to ftrace.
+config FUNCTION_PROFILER
+ bool "Kernel function profiler"
+ depends on FUNCTION_TRACER
+ default n
+ help
+ This option enables the kernel function profiler. A file is created
+ in debugfs called function_profile_enabled which defaults to zero.
+ When a 1 is echoed into this file profiling begins, and when a
+ zero is entered, profiling stops. A file in the trace_stats
+ directory called functions, that show the list of functions that
+ have been hit and their counters.
+
+ If in doubt, say N
+
config FTRACE_MCOUNT_RECORD
def_bool y
depends on DYNAMIC_FTRACE
config FTRACE_STARTUP_TEST
bool "Perform a startup test on ftrace"
- depends on TRACING && DEBUG_KERNEL && !BOOT_TRACER
+ depends on TRACING
select FTRACE_SELFTEST
help
This option performs a series of startup tests on ftrace. On bootup
functioning properly. It will do tests on all the configured
tracers of ftrace.
+config MMIOTRACE
+ bool "Memory mapped IO tracing"
+ depends on HAVE_MMIOTRACE_SUPPORT && PCI
+ select TRACING
+ help
+ Mmiotrace traces Memory Mapped I/O access and is meant for
+ debugging and reverse engineering. It is called from the ioremap
+ implementation and works via page faults. Tracing is disabled by
+ default and can be enabled at run-time.
+
+ See Documentation/trace/mmiotrace.txt.
+ If you are not helping to develop drivers, say N.
+
+config MMIOTRACE_TEST
+ tristate "Test module for mmiotrace"
+ depends on MMIOTRACE && m
+ help
+ This is a dumb module for testing mmiotrace. It is very dangerous
+ as it will write garbage to IO memory starting at a given address.
+ However, it should be safe to use on e.g. unused portion of VRAM.
+
+ Say N, unless you absolutely know what you are doing.
+
endmenu
+
+endif # TRACING_SUPPORT
+