Re: [PATCH v7 2/3] arm64: implement ftrace with regs

[Steven Rostedt]

On Wed, 3 Apr 2019 03:48:43 +0100
Mark Rutland <mark.rutland@xxxxxxx> wrote:

> We currently have:
> 
> ftrace_make_nop(mod, rec, addr)
> ftrace_make_call(rec, addr)
> ftrace_modify_call(rec, old_addr, new_addr)
> 
> ... whereas we could have:
> 
> ftrace_call_init(mod, rec)
> ftrace_call_enable(rec, addr)
> ftrace_call_disable(rec, addr)
> ftrace_call_modify(rec, old_addr, new_addr)
> 
> ... so we wouldn't need to special-case anything for initialization (and
> don't need MCOUNT_ADDR at all), and it would be clearer as to what was
> happening at each stage.

Just a note. I would be OK if someone wants to work in changing the
ftrace interface to be this. I'll review the code, but I don't have the
cycles to implement such a change.

-- Steve