Reputation: 1035
I want to trace 2 functions in some kernel module that are called during suspend/resume.
These functions do appear in "available_filter_functions".
This is how I am configuring ftrace:
echo nop > current_tracer
echo fun_suspend > set_ftrace_filter
echo fun_resume > set_ftrace_filter
echo function_graph > current_tracer
When I suspend/resume the machine, these functions are called for sure (I see logs) yet do not appear in cat trace
Does anyone have any idea?
Thanks,
Matti
Upvotes: 3
Views: 826
Reputation: 1035
The functions that i wanted to measure were in a suspend resume flow. And apparently suspend & resume are very problematic for tracing functions(dynamic tracing), and ftrace disables the tracing during this process. So for now you cannot trace those functions.
Upvotes: 3