问题
I enabled ftrace event tracing for sys_enter_openat syscall. The respective output format given at events/syscalls/sys_enter_openat/format is
print fmt: "dfd: 0x%08lx, filename: 0x%08lx, flags: 0x%08lx, mode: 0x%08lx", ((unsigned long)(REC->dfd)), ((unsigned long)(REC->filename)), ((unsigned long)(REC->flags)), ((unsigned long)(REC->mode))
As expected a sample output line to ftrace is something like
msm_irqbalance-1338 [000] ...1 211710.033931: sys_openat(dfd: ffffff9c, filename: 5af693f224, flags: 2, mode: 0)
Is there a way to change output format such that filename: 5af693f224 can be shown as filename: <string> instead of address?
I guess this would have been possible using systemtap or krpobe but my setup does not allow its use as of now.
来源：https://stackoverflow.com/questions/55443204/change-format-of-syscall-event-trace-output-to-ftrace