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=-17.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 30B06C433DB for ; Mon, 8 Mar 2021 12:59:56 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 980576518F for ; Mon, 8 Mar 2021 12:59:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 980576518F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 08C268D002B; Mon, 8 Mar 2021 07:59:55 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 063298D001D; Mon, 8 Mar 2021 07:59:55 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E94138D002B; Mon, 8 Mar 2021 07:59:54 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0115.hostedemail.com [216.40.44.115]) by kanga.kvack.org (Postfix) with ESMTP id CE19A8D001D for ; Mon, 8 Mar 2021 07:59:54 -0500 (EST) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 7C6298249980 for ; Mon, 8 Mar 2021 12:59:54 +0000 (UTC) X-FDA: 77896714308.16.9387235 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf11.hostedemail.com (Postfix) with ESMTP id 1D7DA2000393 for ; Mon, 8 Mar 2021 12:59:49 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id A40A364FB3; Mon, 8 Mar 2021 12:59:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1615208391; bh=wxbL/Pa2LuwpiP3JjTmeepdQiCQNIv7MrwRtEg7zXKs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Axro0NZGoslIDIELA+vcrcmqfYkqa2Kispoq8GG1PhQ+GbLbBiVjYT8i8jgLKG4+t 0fv43dyqgy73NVWZvlxfP7NEXWO08+h2cNMWE5stsP7Xn2lITSc9qLMVnWFStmBVXE vs1r1s8hmLch1KCzGcG4ydisTj2Ge23kJtK8xl42cLMN2A8UiDNErKDw5DcZHIFbD6 9K8aQt38rkcpeItasZYjaZvhNVeGX18YxVC/VGGk2v8hRYu0rhxACMwLvrBvkRVoeZ F7aueLZ/eZ9SROhzZ4ZBToOl9R3Tct1GI87ov0yEXcXIT5M1xYVSUtTNMog3TwlzFj rbibwoRAigyVA== Date: Mon, 8 Mar 2021 12:59:46 +0000 From: Will Deacon To: Barry Song Cc: corbet@lwn.net, linux-doc@vger.kernel.org, akpm@linux-foundation.org, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linuxarm@openeuler.org, Mel Gorman , Andy Lutomirski , Catalin Marinas Subject: Re: [PATCH] Documentation/features: mark BATCHED_UNMAP_TLB_FLUSH doesn't apply to ARM64 Message-ID: <20210308125946.GA26015@willie-the-truck> References: <20210223003230.11976-1-song.bao.hua@hisilicon.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210223003230.11976-1-song.bao.hua@hisilicon.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-Stat-Signature: zswb8st6yaq3rd96crgyk6krp5gx8y6g X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 1D7DA2000393 Received-SPF: none (kernel.org>: No applicable sender policy available) receiver=imf11; identity=mailfrom; envelope-from=""; helo=mail.kernel.org; client-ip=198.145.29.99 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1615208389-917519 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Feb 23, 2021 at 01:32:30PM +1300, Barry Song wrote: > BATCHED_UNMAP_TLB_FLUSH is used on x86 to do batched tlb shootdown by > sending one IPI to TLB flush all entries after unmapping pages rather > than sending an IPI to flush each individual entry. > On arm64, tlb shootdown is done by hardware. Flush instructions are > innershareable. The local flushes are limited to the boot (1 per CPU) > and when a task is getting a new ASID. > So marking this feature as "TODO" is not proper. ".." isn't good as > well. So this patch adds a "N/A" for this kind of features which are > not needed on some architectures. > > Cc: Mel Gorman > Cc: Andy Lutomirski > Cc: Catalin Marinas > Cc: Will Deacon > Signed-off-by: Barry Song > --- > Documentation/features/arch-support.txt | 1 + > Documentation/features/vm/TLB/arch-support.txt | 2 +- > 2 files changed, 2 insertions(+), 1 deletion(-) > > diff --git a/Documentation/features/arch-support.txt b/Documentation/features/arch-support.txt > index d22a1095e661..118ae031840b 100644 > --- a/Documentation/features/arch-support.txt > +++ b/Documentation/features/arch-support.txt > @@ -8,4 +8,5 @@ The meaning of entries in the tables is: > | ok | # feature supported by the architecture > |TODO| # feature not yet supported by the architecture > | .. | # feature cannot be supported by the hardware > + | N/A| # feature doesn't apply to the architecture > > diff --git a/Documentation/features/vm/TLB/arch-support.txt b/Documentation/features/vm/TLB/arch-support.txt > index 30f75a79ce01..0d070f9f98d8 100644 > --- a/Documentation/features/vm/TLB/arch-support.txt > +++ b/Documentation/features/vm/TLB/arch-support.txt > @@ -9,7 +9,7 @@ > | alpha: | TODO | > | arc: | TODO | > | arm: | TODO | > - | arm64: | TODO | > + | arm64: | N/A | > | c6x: | .. | > | csky: | TODO | > | h8300: | .. | Acked-by: Will Deacon Will