diff options
Diffstat (limited to 'Documentation/tools')
| -rw-r--r-- | Documentation/tools/rtla/common_timerlat_description.rst | 10 | ||||
| -rw-r--r-- | Documentation/tools/rtla/rtla-timerlat.rst | 9 |
2 files changed, 12 insertions, 7 deletions
diff --git a/Documentation/tools/rtla/common_timerlat_description.rst b/Documentation/tools/rtla/common_timerlat_description.rst index 321201cb8597..49fcae3ffdec 100644 --- a/Documentation/tools/rtla/common_timerlat_description.rst +++ b/Documentation/tools/rtla/common_timerlat_description.rst @@ -6,5 +6,13 @@ debugging of operating system timer latency. The *timerlat* tracer outputs information in two ways. It periodically prints the timer latency at the timer *IRQ* handler and the *Thread* -handler. It also enable the trace of the most relevant information via +handler. It also enables the trace of the most relevant information via **osnoise:** tracepoints. + +The **rtla timerlat** tool sets the options of the *timerlat* tracer +and collects and displays a summary of the results. By default, +the collection is done synchronously in kernel space using a dedicated +BPF program attached to the *timerlat* tracer. If either BPF or +the **osnoise:timerlat_sample** tracepoint it attaches to is +unavailable, the **rtla timerlat** tool falls back to using tracefs to +process the data asynchronously in user space. diff --git a/Documentation/tools/rtla/rtla-timerlat.rst b/Documentation/tools/rtla/rtla-timerlat.rst index 44a49e6f302b..20e2d259467f 100644 --- a/Documentation/tools/rtla/rtla-timerlat.rst +++ b/Documentation/tools/rtla/rtla-timerlat.rst @@ -16,13 +16,10 @@ DESCRIPTION .. include:: common_timerlat_description.rst -The *timerlat* tracer outputs information in two ways. It periodically -prints the timer latency at the timer *IRQ* handler and the *Thread* handler. -It also provides information for each noise via the **osnoise:** tracepoints. The **rtla timerlat top** mode displays a summary of the periodic output -from the *timerlat* tracer. The **rtla hist hist** mode displays a histogram -of each tracer event occurrence. For further details, please refer to the -respective man page. +from the *timerlat* tracer. The **rtla timerlat hist** mode displays +a histogram of each tracer event occurrence. For further details, please +refer to the respective man page. MODES ===== |