On Tue, Oct 30, 2012 at 3:05 PM, Steven Rostedt <[email protected]> wrote: > On Tue, 2012-10-30 at 14:51 +0000, Will Newton wrote: >> Scan any text section whose name begins with ".text." so >> we will find all the functions in a kernel built with >> -ffunction-sections. > > A couple of things. > > First, I'm very paranoid about a blanket "ok" on sections. We must > guarantee that all sections that starts with ".text" never is freed. And > if it is freed, that it must inform ftrace that it's about to free it > before it does. If we can not guarantee this, then we can't do it.
I share that concern, however it looks like it should be safe. The two architectures in tree that enable -ffunction-sections by default are parisc and score and they both use a .text.* wildcard in their linker script. If the support for building with --gc-sections is ever completed then that would require -ffunction-sections and a similar wildcard to be applied to section names. > Second, most archs today do not use recordmcount.pl. They use the new > recordmcount.c file. Ok, thanks for letting me know. Is the plan to switch over to recordmcount.c exclusively at some point? The following architectures have some support in recordmcount.c but do not enable it: sh, powerpc, ia64 And the following have no support in recordmcount.c as yet: blackfin, microblaze -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
