Re: [PATCH] x86/asm: Remove unused COMPILE_OFFSETS macro from asm-offsets.c

From: Vincent Mailhol
Date: Mon Nov 28 2022 - 05:11:27 EST


On Mon, 28 Nov 2022 12:15:06 +0300, Kirill A. Shutemov wrote:
> On Sun, Nov 27, 2022 at 03:23:35PM +0900, Vincent Mailhol wrote:
> > Following [1], the macro COMPILE_OFFSETS becomes unused:
>
> Really? I see #ifdef COMPILE_OFFSETS in ftrace.h. Hm?
>
> Have you tested your patch with CONFIG_FTRACE_SYSCALLS=y and
> CONFIG_IA32_EMULATION=y?

Even if I activate those two configurations, the compiler still
tells me it is unused:

$ grep -E "CONFIG_FTRACE_SYSCALLS|CONFIG_IA32_EMULATION" .config
CONFIG_IA32_EMULATION=y
CONFIG_FTRACE_SYSCALLS=y

$ make W=2 arch/x86/kernel/asm-offsets.o
<...>
arch/x86/kernel/asm-offsets.c:7: warning: macro "COMPILE_OFFSETS" is not used [-Wunused-macros]
<...>

> > $ make W=2 arch/x86/kernel/asm-offsets.o
> > <...>
> > arch/x86/kernel/asm-offsets.c:7: warning: macro "COMPILE_OFFSETS" is not used [-Wunused-macros]
> > <...>
> >
> > Remove COMPILE_OFFSETS macro.
> >
> > [1] commit debc5a1ec0d1 ("KVM: x86: use a separate asm-offsets.c file")
> > Link: https://git.kernel.org/torvalds/linux/c/debc5a1ec0d1
> >
> > Fixes: debc5a1ec0d1 ("KVM: x86: use a separate asm-offsets.c file")
> > Signed-off-by: Vincent Mailhol <mailhol.vincent@xxxxxxxxxx>
> > ---
> > arch/x86/kernel/asm-offsets.c | 1 -
> > 1 file changed, 1 deletion(-)
> >
> > diff --git a/arch/x86/kernel/asm-offsets.c b/arch/x86/kernel/asm-offsets.c
> > index 437308004ef2..cf2e02bafbef 100644
> > --- a/arch/x86/kernel/asm-offsets.c
> > +++ b/arch/x86/kernel/asm-offsets.c
> > @@ -4,7 +4,6 @@
> > * This code generates raw asm output which is post-processed to extract
> > * and format the required data.
> > */
> > -#define COMPILE_OFFSETS
> >
> > #include <linux/crypto.h>
> > #include <linux/sched.h>