On Tue, Mar 11, 2025 at 12:49:36PM +0100, Tomas Glozar wrote: > Add dependencies needed to build rtla with BPF sample collection support > to README, and document both ways of sample collection in the manpages. > > Signed-off-by: Tomas Glozar <tglozar@xxxxxxxxxx> > --- > Documentation/tools/rtla/common_timerlat_description.rst | 8 ++++++++ > tools/tracing/rtla/README.txt | 7 +++++++ > 2 files changed, 15 insertions(+) > > diff --git a/Documentation/tools/rtla/common_timerlat_description.rst b/Documentation/tools/rtla/common_timerlat_description.rst > index 8cd3e717baa8..49fcae3ffdec 100644 > --- a/Documentation/tools/rtla/common_timerlat_description.rst > +++ b/Documentation/tools/rtla/common_timerlat_description.rst > @@ -8,3 +8,11 @@ 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 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 In the last phrase, s/is/are/. So that "If either... or... are unavailable". Luis > +unavailable, the **rtla timerlat** tool falls back to using tracefs to > +process the data asynchronously in user space. > diff --git a/tools/tracing/rtla/README.txt b/tools/tracing/rtla/README.txt > index dd5621038c55..43e98311d10f 100644 > --- a/tools/tracing/rtla/README.txt > +++ b/tools/tracing/rtla/README.txt > @@ -13,6 +13,13 @@ RTLA depends on the following libraries and tools: > - libtraceevent > - libcpupower (optional, for --deepest-idle-state) > > +For BPF sample collection support, the following extra dependencies are > +required: > + > + - libbpf 1.0.0 or later > + - bpftool with skeleton support > + - clang with BPF CO-RE support > + > It also depends on python3-docutils to compile man pages. > > For development, we suggest the following steps for compiling rtla: > -- > 2.48.1 > ---end quoted text---
