diff options
Diffstat (limited to 'kernel/trace/Kconfig')
| -rw-r--r-- | kernel/trace/Kconfig | 33 |
1 files changed, 20 insertions, 13 deletions
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index fea2f14a5d62..7738d486e937 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -143,7 +143,6 @@ config FUNCTION_GRAPH_TRACER 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 @@ -171,15 +170,15 @@ config INTERRUPT_OFF_HIST bool "Interrupts-off Latency Histogram" depends on IRQSOFF_TRACER help - This option generates a continuously updated histogram (one per cpu) + This option generates continuously updated histograms (one per cpu) of the duration of time periods with interrupts disabled. The - histogram is disabled by default. To enable it, write a non-zero - number to the related file in + 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, an additional histogram (one - per cpu) is generated that accumulates the duration of time periods + 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. config PREEMPT_TRACER @@ -208,15 +207,15 @@ config PREEMPT_OFF_HIST bool "Preemption-off Latency Histogram" depends on PREEMPT_TRACER help - This option generates a continuously updated histogram (one per cpu) + This option generates continuously updated histograms (one per cpu) of the duration of time periods with preemption disabled. The - histogram is disabled by default. To enable it, write a non-zero + 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, an additional histogram (one - per cpu) is generated that accumulates the duration of time periods + 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. config SCHED_TRACER @@ -232,12 +231,20 @@ config WAKEUP_LATENCY_HIST bool "Scheduling Latency Histogram" depends on SCHED_TRACER help - This option generates a continuously updated histogram (one per cpu) - of the scheduling latency of the highest priority task. The histogram - is disabled by default. To enable it, write a non-zero number to + 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. + config SYSPROF_TRACER bool "Sysprof Tracer" depends on X86 |