2 # Architectures that offer an FTRACE implementation should select HAVE_FTRACE:
7 config TRACER_MAX_TRACE
15 bool "Kernel Function Tracer"
16 depends on DEBUG_KERNEL && HAVE_FTRACE
19 select CONTEXT_SWITCH_TRACER
21 Enable the kernel to trace every kernel function. This is done
22 by using a compiler feature to insert a small, 5-byte No-Operation
23 instruction to the beginning of every kernel function, which NOP
24 sequence is then dynamically patched into a tracer call when
25 tracing is enabled by the administrator. If it's runtime disabled
26 (the bootup default), then the overhead of the instructions is very
27 small and not measurable even in micro-benchmarks.
30 bool "Interrupts-off Latency Tracer"
32 depends on TRACE_IRQFLAGS_SUPPORT
33 depends on GENERIC_TIME
36 select TRACER_MAX_TRACE
38 This option measures the time spent in irqs-off critical
39 sections, with microsecond accuracy.
41 The default measurement method is a maximum search, which is
42 disabled by default and can be runtime (re-)started
45 echo 0 > /debugfs/tracing/tracing_max_latency
48 bool "Scheduling Latency Tracer"
49 depends on DEBUG_KERNEL
51 select CONTEXT_SWITCH_TRACER
52 select TRACER_MAX_TRACE
54 This tracer tracks the latency of the highest priority task
55 to be scheduled in, starting from the point it has woken up.
57 config CONTEXT_SWITCH_TRACER
58 bool "Trace process context switches"
59 depends on DEBUG_KERNEL
63 This tracer gets called from the context switch and records
64 all switching of tasks.