Linux Function Tracer Support

(Farzad Farshchi) #1

Does the Function Tracer ( work in RISC-V Linux?

(Paul Walmsley) #2

Yes, the function tracer does work. You may need to enable it in your kernel .config file (CONFIG_FUNCTION_TRACER=y) and rebuild the kernel. Once that’s done and you’ve booted into userspace, mount debugfs by running something like this as root:

mkdir -p /debug; mount -t debugfs none /debug

Change into the debug tracing directory:

cd /debug/tracing

The README virtual file in that “directory” describes how to use the debugfs tracing interface.

(Farzad Farshchi) #3

Thanks for your answer. My issue is I can’t find “available_filter_functions” and “set_graph_function” to filter the trace based on function name.

(Paul Walmsley) #4

Most likely the kernel that you’re using was built with CONFIG_FUNCTION_TRACER disabled.