Re: [PATCH 07/12] x86/tlb: use INVLPGB in flush_tlb_all

[Dave Hansen <dave.hansen@xxxxxxxxx>]

On 12/30/24 09:53, Rik van Riel wrote:
> --- a/arch/x86/mm/tlb.c
> +++ b/arch/x86/mm/tlb.c
> @@ -1074,6 +1074,12 @@ static void do_flush_tlb_all(void *info)
>  void flush_tlb_all(void)
>  {
>  	count_vm_tlb_event(NR_TLB_REMOTE_FLUSH);
> +	if (cpu_feature_enabled(X86_FEATURE_INVLPGB)) {
> +		guard(preempt)();
> +		invlpgb_flush_all();
> +		tlbsync();
> +		return;
> +	}

After seeing a few of these, I'd really prefer that the preempt and
tlbsync() logic be hidden in the invlpgb_*() helper, or *a* helper at least.

This would be a lot easier on the eyes if it were something like:

	flushed = invlpgb_flush_all();
	if (flushed)
		return;

or even:

	if (cpu_feature_enabled(X86_FEATURE_INVLPGB)) {
		invlpgb_flush_all();
		return;
	}