Re: [PATCH] x86/mm/tlb: avoid reading mm_tlb_gen when possible

From: Nadav Amit
Date: Mon Jun 06 2022 - 12:28:54 EST


On Jun 6, 2022, at 8:29 AM, Dave Hansen <dave.hansen@xxxxxxxxx> wrote:

> ⚠ External Email
>
> On 3/22/22 15:07, Nadav Amit wrote:
>> + if (f->new_tlb_gen <= local_tlb_gen) {
>> + /*
>> + * We are already up to date in respect to f->new_tlb_gen.
>> + * While the core might be still behind mm_tlb_gen, checking
>> + * mm_tlb_gen unnecessarily would have negative caching effects
>> + * so avoid it.
>> + */
>> + return;
>> + }
>> +
>
> Nit: There's at least one "we" in here that needs to get fixed up. I'll
> plan to do that when I apply it, but a v2 with that fixed and Peter's
> ack added might save me five minutes.

No good deed goes unpunished.

I’ll send v2 later today.