Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753413AbdFVSKd (ORCPT ); Thu, 22 Jun 2017 14:10:33 -0400 Received: from mail.kernel.org ([198.145.29.99]:56714 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751224AbdFVSKc (ORCPT ); Thu, 22 Jun 2017 14:10:32 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6D27D22B66 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=luto@kernel.org MIME-Version: 1.0 In-Reply-To: References: From: Andy Lutomirski Date: Thu, 22 Jun 2017 11:10:10 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v3 11/11] x86/mm: Try to preserve old TLB entries using PCID To: Nadav Amit Cc: Andy Lutomirski , X86 ML , "linux-kernel@vger.kernel.org" , Borislav Petkov , Linus Torvalds , Andrew Morton , Mel Gorman , "linux-mm@kvack.org" , Rik van Riel , Dave Hansen , Arjan van de Ven , Peter Zijlstra Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 890 Lines: 28 On Thu, Jun 22, 2017 at 9:09 AM, Nadav Amit wrote: > Andy Lutomirski wrote: > >> >> --- a/arch/x86/mm/init.c >> +++ b/arch/x86/mm/init.c >> @@ -812,6 +812,7 @@ void __init zone_sizes_init(void) >> >> DEFINE_PER_CPU_SHARED_ALIGNED(struct tlb_state, cpu_tlbstate) = { >> .loaded_mm = &init_mm, >> + .next_asid = 1, > > I think this is a remainder from previous version of the patches, no? It > does not seem necessary and may be confusing (ctx_id 0 is reserved, but not > asid 0). Hmm. It's no longer needed for correctness, but init_mm still lands in slot 0, and it seems friendly to avoid immediately stomping it. Admittedly, this won't make any practical difference since it'll only happen once per cpu. > > Other than that, if you want, you can put for the entire series: > > Reviewed-by: Nadav Amit > Thanks!