[PATCH] powerpc: Define and use PPC_ELF_ABI_v2

[Joel Stanley]

On Thu, Apr 28, 2016 at 7:08 PM, Michael Ellerman <mpe at ellerman.id.au> wrote:
> We're approaching 20 locations where we need to check for ELF ABI v2.
> That's fine, except the logic is a bit awkward, because we have to check
> that _CALL_ELF is defined and then what its value is.
>
> So check it once in asm/types.h and define PPC_ELF_ABI_v2 when ELF ABI
> v2 is detected.
>
> We don't add explicit includes of asm/types.h because it's included
> basically everywhere via compiler.h.

Thank you! I always wondered why we didn't do this.

> Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>

Reviewed-by: Joel Stanley <joel at jms.id.au>

> ---
>  arch/powerpc/include/asm/code-patching.h | 6 +++---
>  arch/powerpc/include/asm/ftrace.h        | 2 +-
>  arch/powerpc/include/asm/kprobes.h       | 4 ++--
>  arch/powerpc/include/asm/linkage.h       | 2 +-
>  arch/powerpc/include/asm/ppc_asm.h       | 4 ++--
>  arch/powerpc/include/asm/ptrace.h        | 2 +-
>  arch/powerpc/include/asm/sections.h      | 2 +-
>  arch/powerpc/include/asm/types.h         | 4 ++++
>  arch/powerpc/kernel/entry_64.S           | 2 +-
>  arch/powerpc/kernel/head_64.S            | 2 +-
>  arch/powerpc/kernel/kprobes.c            | 2 +-
>  arch/powerpc/kernel/misc_64.S            | 2 +-
>  arch/powerpc/kernel/module_64.c          | 4 ++--
>  arch/powerpc/kvm/book3s_interrupts.S     | 2 +-
>  arch/powerpc/kvm/book3s_rmhandlers.S     | 2 +-
>  15 files changed, 23 insertions(+), 19 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/code-patching.h b/arch/powerpc/include/asm/code-patching.h
> index 994c60a857ce..d325b35315d3 100644
> --- a/arch/powerpc/include/asm/code-patching.h
> +++ b/arch/powerpc/include/asm/code-patching.h
> @@ -50,7 +50,7 @@ void __patch_exception(int exc, unsigned long addr);
>  static inline unsigned long ppc_function_entry(void *func)
>  {
>  #if defined(CONFIG_PPC64)
> -#if defined(_CALL_ELF) && _CALL_ELF == 2
> +#ifdef PPC_ELF_ABI_v2
>         u32 *insn = func;
>
>         /*
> @@ -90,7 +90,7 @@ static inline unsigned long ppc_function_entry(void *func)
>
>  static inline unsigned long ppc_global_function_entry(void *func)
>  {
> -#if defined(CONFIG_PPC64) && defined(_CALL_ELF) && _CALL_ELF == 2
> +#if defined(CONFIG_PPC64) && defined(PPC_ELF_ABI_v2)

The CONFIG_PPC64 is redundant?

>         /* PPC64 ABIv2 the global entry point is at the address */
>         return (unsigned long)func;
>  #else