[PATCH] powerpc/xmon: Exclude all of xmon/ from ftrace

[Naveen N. Rao]

Hi Michael,
Sorry -- was off since last week.

On 2017/08/15 08:04PM, Michael Ellerman wrote:
> Michael Ellerman <mpe at ellerman.id.au> writes:
> 
> > "Naveen N. Rao" <naveen.n.rao at linux.vnet.ibm.com> writes:
> >
> >> diff --git a/arch/powerpc/xmon/Makefile b/arch/powerpc/xmon/Makefile
> >> index 0b2f771593eb..5f95af64cb8f 100644
> >> --- a/arch/powerpc/xmon/Makefile
> >> +++ b/arch/powerpc/xmon/Makefile
> >> @@ -7,6 +7,19 @@ UBSAN_SANITIZE := n
> >>  
> >>  ccflags-$(CONFIG_PPC64) := $(NO_MINIMAL_TOC)
> >>  
> >> +ifdef CONFIG_FUNCTION_TRACER
> >> +CFLAGS_REMOVE_xmon.o	= -mno-sched-epilog $(CC_FLAGS_FTRACE)
> >> +CFLAGS_REMOVE_nonstdio.o = -mno-sched-epilog $(CC_FLAGS_FTRACE)
> >> +ifdef CONFIG_XMON_DISASSEMBLY
> >> +CFLAGS_REMOVE_ppc-dis.o	= -mno-sched-epilog $(CC_FLAGS_FTRACE)
> >> +CFLAGS_REMOVE_ppc-opc.o	= -mno-sched-epilog $(CC_FLAGS_FTRACE)
> >> +ifdef CONFIG_SPU_BASE
> >> +CFLAGS_REMOVE_spu-dis.o	= -mno-sched-epilog $(CC_FLAGS_FTRACE)
> >> +CFLAGS_REMOVE_spu-opc.o	= -mno-sched-epilog $(CC_FLAGS_FTRACE)
> >> +endif
> >> +endif
> >> +endif
> >
> > Urk.
> >
> > We want to disable it for everything in the directory, so can you do
> > something like:
> >
> >   ORIG_CFLAGS := $(KBUILD_CFLAGS)
> >   KBUILD_CFLAGS = $(subst $(CC_FLAGS_FTRACE),,$(ORIG_CFLAGS))
> 
> Yes:
> 
>   # Disable ftrace for the entire directory
>   ORIG_CFLAGS := $(KBUILD_CFLAGS)
>   KBUILD_CFLAGS = $(subst -mno-sched-epilog,,$(subst $(CC_FLAGS_FTRACE),,$(ORIG_CFLAGS)))
> 
> Seems to work.

Nice -- I had looked for a generic CFLAGS_REMOVE variant, but didn't 
find that. This is much nicer.

Thanks,
Naveen