Re: [RFC][PATCH 07/11] arm/tlb: Convert to generic mmu_gather
From: Will Deacon
Date: Wed Sep 19 2018 - 08:24:25 EST
On Wed, Sep 19, 2018 at 01:28:29PM +0200, Peter Zijlstra wrote:
> On Tue, Sep 18, 2018 at 03:10:34PM +0100, Will Deacon wrote:
> > So whilst I was reviewing this, I realised that I think we should be
> > selecting HAVE_RCU_TABLE_INVALIDATE for arch/arm/ if HAVE_RCU_TABLE_FREE.
> Yes very much so. Let me invert that option, you normally want that,
> except if you don't natively use the linux page-tables.
Yeah, inverting this to be opt-out is definitely the safe thing to do.
Patch below looks good:
Acked-by: Will Deacon <will.deacon@xxxxxxx>
> Subject: asm-generic/tlb: Invert HAVE_RCU_TABLE_INVALIDATE
> From: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> Date: Wed Sep 19 13:24:41 CEST 2018
> Make issuing a TLB invalidate for page-table pages the normal case.
> The reason is twofold:
> - too many invalidates is safer than too few,
> - most architectures use the linux page-tables natively
> and would this require this.
> Make it an opt-out, instead of an opt-in.
> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>