On Sat, 17 Mar 2018 00:46:32 +1100 Michael Ellerman <mpe@xxxxxxxxxxxxxx> wrote: > There is a small but non-zero amount of code required by arches to > suppory non-dynamic (static) ftrace, and more importantly there is the > added work of testing both configurations. > > There are also almost no down sides to dynamic ftrace once it's well > tested, other than a small increase in code/data size. > > So give arches the option to opt-out of supporting static ftrace. > > This is implemented as a DYNAMIC_FTRACE_CHOICE option, which controls > whether DYNAMIC_FTRACE is presented as a user-selectable option or if > it is just enabled based on its dependencies being enabled (because > it's already default y). > > Then the CHOICE option depends on an arch *not* selecting > HAVE_DYNAMIC_FTRACE_ONLY. This would be more natural in reverse, as a > HAVE_STATIC_FTRACE option, but that would require updating every arch. > > Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Why not just add in arch/powerpc/Kconfig: config PPC [..] select DYNAMIC_FTRACE if FUNCTION_TRACER ? It seems to work for me. -- Steve
