Hi Akashi,
On Fri, Feb 28, 2014 at 05:18:37AM +0000, AKASHI Takahiro wrote:
This patchset implements a function tracer on arm64. There was another implementation from Cavium network, but both of us agreed to use my patchset as future base. He is supposed to review this code, too.
The only issue that I had some concern on was "fault protection" code in prepare_ftrace_return(). With discussions with Steven and Tim (as author of arm ftrace), I removed that code since I'm not quite sure about possibility of "fault" occurrences in this function.
The code is tested on ARMv8 Fast Model with the following tracers & events: function tracer with dynamic ftrace function graph tracer with dynamic ftrace syscall tracepoint irqsoff & preemptirqsoff (which use CALLER_ADDRx) and also verified with in-kernel tests, FTRACE_SELFTEST, FTRACE_STARTUP_TEST and EVENT_TRACE_TEST_SYSCALLS.
Prerequisites are:
- "arm64: Add regs_return_value() in syscall.h"
- "arm64: make a single hook to syscall_trace() for all syscall features" patch
It looks like there might be some more dependencies that that. Do you have a branch anywhere containing this series, along with all the dependencies so I can have a play?
Cheers,
Will