The upstream Linux kernel has introduced a funcgraph retval feature for the function_graph tracer. (Commit ID: a1be9ccc57f07d54278be34eed6bd679bc941c97). This feature can be useful for debugging kernel problems, such as root cause analysis for syscall errors. This patch series is to utilize this feature to support printing each function's return value in 'trace-cmd report'. The default is off. Add a ftrace internal option so that users can turn this feature on if they'd like to request for the retval information in the function_graph tracer. Jianfeng Wang (2): trace-cmd ftrace: print function retval in function_graph trace-cmd: Add ftrace options with fgraph retval option lib/trace-cmd/trace-ftrace.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) -- 2.42.1
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