[PATCH v5 03/21] powerpc: remove arguments from fault handler functions

[Christophe Leroy]

Le 13/01/2021 à 08:31, Nicholas Piggin a écrit :
> Make mm fault handlers all just take the pt_regs * argument and load
> DAR/DSISR from that. Make those that return a value return long.
> 
> This is done to make the function signatures match other handlers, which
> will help with a future patch to add wrappers. Explicit arguments could
> be added for performance but that would require more wrapper macro
> variants.
> 
> Signed-off-by: Nicholas Piggin <npiggin at gmail.com>
> ---
>   arch/powerpc/include/asm/asm-prototypes.h     |  4 ++--
>   arch/powerpc/include/asm/book3s/64/mmu-hash.h |  2 +-
>   arch/powerpc/include/asm/bug.h                |  2 +-
>   arch/powerpc/kernel/entry_32.S                |  6 +-----
>   arch/powerpc/kernel/exceptions-64e.S          |  2 --
>   arch/powerpc/kernel/exceptions-64s.S          | 14 ++------------
>   arch/powerpc/kernel/head_40x.S                | 10 +++++-----
>   arch/powerpc/kernel/head_8xx.S                |  6 +++---
>   arch/powerpc/kernel/head_book3s_32.S          |  5 ++---
>   arch/powerpc/kernel/head_booke.h              |  4 +---
>   arch/powerpc/mm/book3s64/hash_utils.c         |  8 +++++---
>   arch/powerpc/mm/book3s64/slb.c                | 11 +++++++----
>   arch/powerpc/mm/fault.c                       |  7 ++++---
>   13 files changed, 34 insertions(+), 47 deletions(-)
> 
> diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
> index 238eacfda7b0..a32157ce0551 100644
> --- a/arch/powerpc/kernel/entry_32.S
> +++ b/arch/powerpc/kernel/entry_32.S
> @@ -277,7 +277,7 @@ reenable_mmu:
>   	 * r3 can be different from GPR3(r1) at this point, r9 and r11
>   	 * contains the old MSR and handler address respectively,
>   	 * r4 & r5 can contain page fault arguments that need to be passed

The line above should be dropped as well (its end on the line below is dropped already)


> -	 * along as well. r0, r6-r8, r12, CCR, CTR, XER etc... are left
> +	 * r0, r4-r8, r12, CCR, CTR, XER etc... are left
>   	 * clobbered as they aren't useful past this point.
>   	 */
>   

Christophe