On Wed, Nov 18, 2020 at 02:07:30PM -0800, Sami Tolvanen wrote: > DYNAMIC_FTRACE_WITH_REGS uses -fpatchable-function-entry, which makes > running recordmcount unnecessary as there are no mcount calls in object > files, and __mcount_loc doesn't need to be generated. > > While there's normally no harm in running recordmcount even when it's > not strictly needed, this won't work with LTO as we have LLVM bitcode > instead of ELF objects. > > This change selects FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY, which > disables recordmcount when patchable function entries are used instead. > > Signed-off-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx> > --- > arch/arm64/Kconfig | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > index 1515f6f153a0..c7f07978f5b6 100644 > --- a/arch/arm64/Kconfig > +++ b/arch/arm64/Kconfig > @@ -158,6 +158,8 @@ config ARM64 > select HAVE_DYNAMIC_FTRACE > select HAVE_DYNAMIC_FTRACE_WITH_REGS \ > if $(cc-option,-fpatchable-function-entry=2) > + select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \ > + if DYNAMIC_FTRACE_WITH_REGS I don't really understand why this is in the arch header file, rather than have the core code check for "fpatchable-function-entry=2" and expose a CC_HAS_PATCHABLE_FUNCTION_ENTRY, but in the interest of making some progress on this series: Acked-by: Will Deacon <will@xxxxxxxxxx> Will
