On Mon, 28 Jul 2008, Ingo Molnar wrote: > * Hugh Dickins <[EMAIL PROTECTED]> wrote: > > > I rather think CONFIG_FRAME_POINTER shouldn't exist at all (or be a > > private, config-user-invisible, specific-to-a-few-arches thing): what > > one wants to configure is how far to sacrifice cpu performance and > > kernel smallness to getting a good stacktrace. Frame pointer is just > > an implementation detail on that, appropriate to some arches. Perhaps > > three settings: no stacktrace, fair stacktrace, best stacktrace. > > actually, we consciously use and rely on frame pointers on x86. The > runtime cost on 64-bit is miniscule and the improved backtrace output in > recent kernels makes backtraces _much_ easier to interpret:
Just to clarify, no way was I criticizing the use of frame pointers on x86. What I don't care for is that CONFIG_FRAME_POINTER is used by common code (e.g. top level Makefile, and various debug Kconfigs), when I see it as an arch-specific technique for getting best stacktrace. Hugh _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev