diff options
| author | Hauke Mehrtens <hmehrtens@maxlinear.com> | 2020-12-03 18:49:12 +0100 |
|---|---|---|
| committer | Hauke Mehrtens <hauke@hauke-m.de> | 2020-12-16 22:11:19 +0100 |
| commit | 1926ffb5ab3ce15e20445f52e6a44a9d9c2295c5 (patch) | |
| tree | da5e13b2a91979f2694420146e6de13c064122b1 | |
| parent | 47f30a566e4e76738464c5c7e6a2f7feb4b48410 (diff) | |
| download | upstream-1926ffb5ab3ce15e20445f52e6a44a9d9c2295c5.tar.gz upstream-1926ffb5ab3ce15e20445f52e6a44a9d9c2295c5.tar.bz2 upstream-1926ffb5ab3ce15e20445f52e6a44a9d9c2295c5.zip | |
build: Add IRQSOFF and PREEMPT TRACER kernel config option
This adds the CONFIG_IRQSOFF_TRACER and the CONFIG_PREEMPT_TRACER kernel
configuration option to the OpenWrt menu. This can be used to debug
latencies in the system.
The CONFIG_PREEMPT_TRACER option needs the CONFIG_PREEMPT option which is
supposed to be used for Low-Latency Desktop and not used by many targets
in OpenWrt.
The help text is copied from the Linux kernel Kconfig.
Signed-off-by: Hauke Mehrtens <hmehrtens@maxlinear.com>
| -rw-r--r-- | config/Config-kernel.in | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/config/Config-kernel.in b/config/Config-kernel.in index 3f013aa2b2..22e2286b8d 100644 --- a/config/Config-kernel.in +++ b/config/Config-kernel.in @@ -266,6 +266,40 @@ config KERNEL_FUNCTION_PROFILER depends on KERNEL_FUNCTION_TRACER default n +config KERNEL_IRQSOFF_TRACER + bool "Interrupts-off Latency Tracer" + depends on KERNEL_FTRACE + help + This option measures the time spent in irqs-off critical + sections, with microsecond accuracy. + + The default measurement method is a maximum search, which is + disabled by default and can be runtime (re-)started + via: + + echo 0 > /sys/kernel/debug/tracing/tracing_max_latency + + (Note that kernel size and overhead increase with this option + enabled. This option and the preempt-off timing option can be + used together or separately.) + +config KERNEL_PREEMPT_TRACER + bool "Preemption-off Latency Tracer" + depends on KERNEL_FTRACE + help + This option measures the time spent in preemption-off critical + sections, with microsecond accuracy. + + The default measurement method is a maximum search, which is + disabled by default and can be runtime (re-)started + via: + + echo 0 > /sys/kernel/debug/tracing/tracing_max_latency + + (Note that kernel size and overhead increase with this option + enabled. This option and the irqs-off timing option can be + used together or separately.) + config KERNEL_DEBUG_KERNEL bool default n |