kernel/trace/Kconfig

   1 #
   2 # Architectures that offer an FTRACE implementation should select HAVE_FTRACE:
   3 #
   4 config HAVE_FTRACE
   5         bool
   6
   7 config TRACER_MAX_TRACE
   8         bool
   9
  10 config TRACING
  11         bool
  12         select DEBUG_FS
  13
  14 config FTRACE
  15         bool "Kernel Function Tracer"
  16         depends on DEBUG_KERNEL && HAVE_FTRACE
  17         select FRAME_POINTER
  18         select TRACING
  19         select CONTEXT_SWITCH_TRACER
  20         help
  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.
  28
  29 config IRQSOFF_TRACER
  30         bool "Interrupts-off Latency Tracer"
  31         default n
  32         depends on TRACE_IRQFLAGS_SUPPORT
  33         depends on GENERIC_TIME
  34         select TRACE_IRQFLAGS
  35         select TRACING
  36         select TRACER_MAX_TRACE
  37         help
  38           This option measures the time spent in irqs-off critical
  39           sections, with microsecond accuracy.
  40
  41           The default measurement method is a maximum search, which is
  42           disabled by default and can be runtime (re-)started
  43           via:
  44
  45               echo 0 > /debugfs/tracing/tracing_max_latency
  46
  47           (Note that kernel size and overhead increases with this option
  48           enabled. This option and the preempt-off timing option can be
  49           used together or separately.)
  50
  51 config PREEMPT_TRACER
  52         bool "Preemption-off Latency Tracer"
  53         default n
  54         depends on GENERIC_TIME
  55         depends on PREEMPT
  56         select TRACING
  57         select TRACER_MAX_TRACE
  58         help
  59           This option measures the time spent in preemption off critical
  60           sections, with microsecond accuracy.
  61
  62           The default measurement method is a maximum search, which is
  63           disabled by default and can be runtime (re-)started
  64           via:
  65
  66               echo 0 > /debugfs/tracing/tracing_max_latency
  67
  68           (Note that kernel size and overhead increases with this option
  69           enabled. This option and the irqs-off timing option can be
  70           used together or separately.)
  71
  72 config SCHED_TRACER
  73         bool "Scheduling Latency Tracer"
  74         depends on DEBUG_KERNEL
  75         select TRACING
  76         select CONTEXT_SWITCH_TRACER
  77         select TRACER_MAX_TRACE
  78         help
  79           This tracer tracks the latency of the highest priority task
  80           to be scheduled in, starting from the point it has woken up.
  81
  82 config CONTEXT_SWITCH_TRACER
  83         bool "Trace process context switches"
  84         depends on DEBUG_KERNEL
  85         select TRACING
  86         select MARKERS
  87         help
  88           This tracer gets called from the context switch and records
  89           all switching of tasks.
  90