From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 75355C433E0 for ; Tue, 2 Feb 2021 11:05:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3040364E0F for ; Tue, 2 Feb 2021 11:05:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229621AbhBBLFF (ORCPT ); Tue, 2 Feb 2021 06:05:05 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40010 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229581AbhBBLFD (ORCPT ); Tue, 2 Feb 2021 06:05:03 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DF65DC061573; Tue, 2 Feb 2021 03:04:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Transfer-Encoding: Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Sender:Reply-To:Content-ID:Content-Description; bh=802YQyw4lVaV4w8imGbhpyRRiN1cRZRaz6c+AUsQRWs=; b=NqhZ+rxVp9Yow+TY9AI2amWfAh JO+yodkACrvGHvFNxEj/vf3efWCjFGugL4mcteq1H824gd9i5ZlDlIrPW8C3nbAfGuOTpze525HTe 2xP2W+k+cutQzmlHKYn+anynD+vSanmaYnWGsOsAcw8YJSVWH5TZozhFg2UWFMS8YW0++2p3IQ5Eq gcLmL0kBbcttFhP+QBSlrxY3Qnu8tU9accSON4v8hKPXf6bnFbok+V5lEUQ2ZvGoXqkBFbOLEi6xv daHIBmL7fak+0wyrIcBNV4VTsrE3kotRk/CWyRWq5I/8320h2+GKvo3JbC3LfcvU3up/oiX+YUqqC SyPLOgvA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94 #2 (Red Hat Linux)) id 1l6tTd-00F5eu-RB; Tue, 02 Feb 2021 11:04:12 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 4BB84301179; Tue, 2 Feb 2021 12:04:09 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 2F66D2B09FDC9; Tue, 2 Feb 2021 12:04:09 +0100 (CET) Date: Tue, 2 Feb 2021 12:04:09 +0100 From: Peter Zijlstra To: Nadav Amit Cc: Nicholas Piggin , Andrea Arcangeli , Andrew Morton , Dave Hansen , "linux-csky@vger.kernel.org" , LKML , Linux-MM , linuxppc-dev , linux-s390 , Andy Lutomirski , Thomas Gleixner , Will Deacon , X86 ML , Yu Zhao Subject: Re: [RFC 11/20] mm/tlb: remove arch-specific tlb_start/end_vma() Message-ID: References: <20210131001132.3368247-1-namit@vmware.com> <20210131001132.3368247-12-namit@vmware.com> <1612247956.0a1r1yjmm3.astroid@bobo.none> <9100B8AE-129A-4E13-8F01-7B9C14C98B4C@vmware.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <9100B8AE-129A-4E13-8F01-7B9C14C98B4C@vmware.com> Precedence: bulk List-ID: X-Mailing-List: linux-csky@vger.kernel.org On Tue, Feb 02, 2021 at 09:54:36AM +0000, Nadav Amit wrote: > > On Feb 2, 2021, at 1:31 AM, Peter Zijlstra wrote: > > > > On Tue, Feb 02, 2021 at 07:20:55AM +0000, Nadav Amit wrote: > >> Arm does not define tlb_end_vma, and consequently it flushes the TLB after > >> each VMA. I suspect it is not intentional. > > > > ARM is one of those that look at the VM_EXEC bit to explicitly flush > > ITLB IIRC, so it has to. > > Hmm… I don’t think Arm is doing that. At least arm64 does not use the > default tlb_flush(), and it does not seem to consider VM_EXEC (at least in > this path): > ARM != ARM64. ARM certainly does, but you're right, I don't think ARM64 does this.