FUNCTION_TRACER: can it be used to trace early bootup functions

Iram Shahzad
2010-05-24T06:53:42Z

Hi

I would like to know whether the Kernel Function Tracer
(kernel/trace/trace_functions) be used to trace early kernel
bootup functions starting from start_kernel?
My arch is ARM, by the way.

I have done some trials but it doesn't seem to trace early
bootup functions. I even made it the default tracer replacing
the nop tracer, but still it doesn't give me trace from
start_kernel.

Looking at the source code, it seems to me that it starts
recording data only after its own initialization. So does it
mean that by design it does not support early tracing?

Please CC me in the reply.

Thanks in advance
Iram