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-rw-r--r--kernel/trace/Kconfig104
1 files changed, 104 insertions, 0 deletions
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index a1d2849f2473..23c737e59ece 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -192,6 +192,24 @@ config IRQSOFF_TRACER
enabled. This option and the preempt-off timing option can be
used together or separately.)
+config INTERRUPT_OFF_HIST
+ bool "Interrupts-off Latency Histogram"
+ depends on IRQSOFF_TRACER
+ help
+ This option generates continuously updated histograms (one per cpu)
+ of the duration of time periods with interrupts disabled. The
+ histograms are disabled by default. To enable them, write a non-zero
+ number to
+
+ /sys/kernel/debug/tracing/latency_hist/enable/preemptirqsoff
+
+ If PREEMPT_OFF_HIST is also selected, additional histograms (one
+ per cpu) are generated that accumulate the duration of time periods
+ when both interrupts and preemption are disabled. The histogram data
+ will be located in the debug file system at
+
+ /sys/kernel/debug/tracing/latency_hist/irqsoff
+
config PREEMPT_TRACER
bool "Preemption-off Latency Tracer"
default n
@@ -214,6 +232,24 @@ config PREEMPT_TRACER
enabled. This option and the irqs-off timing option can be
used together or separately.)
+config PREEMPT_OFF_HIST
+ bool "Preemption-off Latency Histogram"
+ depends on PREEMPT_TRACER
+ help
+ This option generates continuously updated histograms (one per cpu)
+ of the duration of time periods with preemption disabled. The
+ histograms are disabled by default. To enable them, write a non-zero
+ number to
+
+ /sys/kernel/debug/tracing/latency_hist/enable/preemptirqsoff
+
+ If INTERRUPT_OFF_HIST is also selected, additional histograms (one
+ per cpu) are generated that accumulate the duration of time periods
+ when both interrupts and preemption are disabled. The histogram data
+ will be located in the debug file system at
+
+ /sys/kernel/debug/tracing/latency_hist/preemptoff
+
config SCHED_TRACER
bool "Scheduling Latency Tracer"
select GENERIC_TRACER
@@ -223,6 +259,74 @@ config SCHED_TRACER
This tracer tracks the latency of the highest priority task
to be scheduled in, starting from the point it has woken up.
+config WAKEUP_LATENCY_HIST
+ bool "Scheduling Latency Histogram"
+ depends on SCHED_TRACER
+ help
+ This option generates continuously updated histograms (one per cpu)
+ of the scheduling latency of the highest priority task.
+ The histograms are disabled by default. To enable them, write a
+ non-zero number to
+
+ /sys/kernel/debug/tracing/latency_hist/enable/wakeup
+
+ Two different algorithms are used, one to determine the latency of
+ processes that exclusively use the highest priority of the system and
+ another one to determine the latency of processes that share the
+ highest system priority with other processes. The former is used to
+ improve hardware and system software, the latter to optimize the
+ priority design of a given system. The histogram data will be
+ located in the debug file system at
+
+ /sys/kernel/debug/tracing/latency_hist/wakeup
+
+ and
+
+ /sys/kernel/debug/tracing/latency_hist/wakeup/sharedprio
+
+ If both Scheduling Latency Histogram and Missed Timer Offsets
+ Histogram are selected, additional histogram data will be collected
+ that contain, in addition to the wakeup latency, the timer latency, in
+ case the wakeup was triggered by an expired timer. These histograms
+ are available in the
+
+ /sys/kernel/debug/tracing/latency_hist/timerandwakeup
+
+ directory. They reflect the apparent interrupt and scheduling latency
+ and are best suitable to determine the worst-case latency of a given
+ system. To enable these histograms, write a non-zero number to
+
+ /sys/kernel/debug/tracing/latency_hist/enable/timerandwakeup
+
+config MISSED_TIMER_OFFSETS_HIST
+ depends on HIGH_RES_TIMERS
+ select GENERIC_TRACER
+ bool "Missed Timer Offsets Histogram"
+ help
+ Generate a histogram of missed timer offsets in microseconds. The
+ histograms are disabled by default. To enable them, write a non-zero
+ number to
+
+ /sys/kernel/debug/tracing/latency_hist/enable/missed_timer_offsets
+
+ The histogram data will be located in the debug file system at
+
+ /sys/kernel/debug/tracing/latency_hist/missed_timer_offsets
+
+ If both Scheduling Latency Histogram and Missed Timer Offsets
+ Histogram are selected, additional histogram data will be collected
+ that contain, in addition to the wakeup latency, the timer latency, in
+ case the wakeup was triggered by an expired timer. These histograms
+ are available in the
+
+ /sys/kernel/debug/tracing/latency_hist/timerandwakeup
+
+ directory. They reflect the apparent interrupt and scheduling latency
+ and are best suitable to determine the worst-case latency of a given
+ system. To enable these histograms, write a non-zero number to
+
+ /sys/kernel/debug/tracing/latency_hist/enable/timerandwakeup
+
config ENABLE_DEFAULT_TRACERS
bool "Trace process context switches and events"
depends on !GENERIC_TRACER