lkml.org 
[lkml]   [2022]   [Jan]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] arm64: entry: Save some nops when CONFIG_ARM64_PSEUDO_NMI is not set
From
Date
Hi all,

Ping. Any comments?

在 2022/1/12 11:24, He Ying 写道:
> Arm64 pseudo-NMI feature code brings some additional nops
> when CONFIG_ARM64_PSEUDO_NMI is not set, which is not
> necessary. So add necessary ifdeffery to avoid it.
>
> Signed-off-by: He Ying <heying24@huawei.com>
> ---
> arch/arm64/kernel/entry.S | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
> index 2f69ae43941d..ffc32d3d909a 100644
> --- a/arch/arm64/kernel/entry.S
> +++ b/arch/arm64/kernel/entry.S
> @@ -300,6 +300,7 @@ alternative_else_nop_endif
> str w21, [sp, #S_SYSCALLNO]
> .endif
>
> +#ifdef CONFIG_ARM64_PSEUDO_NMI
> /* Save pmr */
> alternative_if ARM64_HAS_IRQ_PRIO_MASKING
> mrs_s x20, SYS_ICC_PMR_EL1
> @@ -307,6 +308,7 @@ alternative_if ARM64_HAS_IRQ_PRIO_MASKING
> mov x20, #GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET
> msr_s SYS_ICC_PMR_EL1, x20
> alternative_else_nop_endif
> +#endif
>
> /* Re-enable tag checking (TCO set on exception entry) */
> #ifdef CONFIG_ARM64_MTE
> @@ -330,6 +332,7 @@ alternative_else_nop_endif
> disable_daif
> .endif
>
> +#ifdef CONFIG_ARM64_PSEUDO_NMI
> /* Restore pmr */
> alternative_if ARM64_HAS_IRQ_PRIO_MASKING
> ldr x20, [sp, #S_PMR_SAVE]
> @@ -339,6 +342,7 @@ alternative_if ARM64_HAS_IRQ_PRIO_MASKING
> dsb sy // Ensure priority change is seen by redistributor
> .L__skip_pmr_sync\@:
> alternative_else_nop_endif
> +#endif
>
> ldp x21, x22, [sp, #S_PC] // load ELR, SPSR
>

\
 
 \ /
  Last update: 2022-01-19 07:42    [W:0.133 / U:0.076 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site