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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id C32BCC433EF for ; Tue, 8 Feb 2022 05:46:57 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id D3D8B6B0074; Tue, 8 Feb 2022 00:46:56 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id CED246B0075; Tue, 8 Feb 2022 00:46:56 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BDBC26B0078; Tue, 8 Feb 2022 00:46:56 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0040.hostedemail.com [216.40.44.40]) by kanga.kvack.org (Postfix) with ESMTP id AFDBE6B0074 for ; Tue, 8 Feb 2022 00:46:56 -0500 (EST) Received: from smtpin10.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 5F477894BD for ; Tue, 8 Feb 2022 05:46:56 +0000 (UTC) X-FDA: 79118528832.10.F59BA44 Received: from mail-pf1-f179.google.com (mail-pf1-f179.google.com [209.85.210.179]) by imf24.hostedemail.com (Postfix) with ESMTP id 78D7A180002 for ; Tue, 8 Feb 2022 05:46:55 +0000 (UTC) Received: by mail-pf1-f179.google.com with SMTP id i30so17017701pfk.8 for ; Mon, 07 Feb 2022 21:46:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=ZWLmgm9buCbXqY23s5VhjmfJZhCL4RghEpABSyXi0/w=; b=0HYhkWbJnwjpTlx6yPo8iGOzEbRV18XhnOFuEUyVggVDiXTNWhIYIA/aPOw0uT/L09 yYlF5uQgKM92dhsGYUFEULlf710NYp+6d5gV72NVyUEGVTIeAnH/far1EjAK173nhvMA GjeUDLqL5ol5Xc/S8j13re2FPQ9DbSQqW4hnoMvWW0ONXTDzniTB/sZvR27PUX0rMR31 2IaLUB3SKzesIpY3I5KoXVmMF8mTMmaVUWVDnPWX1VyYk6Y9IovfyCE5NfGDDwrp7+vU YDwbvjgGwRCxwOisVBbjwLb+EY70DD8YjVX2AO/x2nJabwLLDDkrf3fSuV6Gb6SzM5iE q6uA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=ZWLmgm9buCbXqY23s5VhjmfJZhCL4RghEpABSyXi0/w=; b=Q3TR/hdRKUNAC5DgGhK4dYu4HXSnX2MbhIKcK+29Vf74xKaoUBMv/cp7f3Idmw4aQt 1KD6rf/wklk3iUrt68mWbsSHmM1REO0bJa1OypXuHIs/IukxaeAbCiUm2bc80aNIqnLl Zcz8Ep+dSeX6SOj/+Ebk5Z6hciIxYgcqh89Ptd2pYGpgF6e4Xr7kbNLH+cSkYcjiYh8i k9Ya6JqGdIBr7gpFGwfxsGs26N81YvvzqBGpdyANNd28xRYD/Lm3ga68YNZTMboRa7Po rBf+Erfjd1jwLwl0mHaOQgPgYdrSLbkZzcXW3ziQLv0j9SoMfEsZMBPDOLItkj4Fr9O4 6Kfw== X-Gm-Message-State: AOAM531+m3KRGvtj7ffPGDiGnQm8PP3bGgIkKpCLHj/cprtuudykInS5 ufuR2mBLPtBROpRAGi1YdqXgmw== X-Google-Smtp-Source: ABdhPJwaR77nsHjzpwtt7ubQtGVX/NP0wNsgi1dJyCP5hRbqwsfRyYHkv7pveQ5ABAYLcpJ/rdv9DQ== X-Received: by 2002:a63:df46:: with SMTP id h6mr2348666pgj.26.1644299214205; Mon, 07 Feb 2022 21:46:54 -0800 (PST) Received: from FVFYT0MHHV2J.tiktokcdn.com ([139.177.225.225]) by smtp.gmail.com with ESMTPSA id 20sm1160680pjf.15.2022.02.07.21.46.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 07 Feb 2022 21:46:53 -0800 (PST) From: Muchun Song To: will@kernel.org, akpm@linux-foundation.org, david@redhat.com, bodeddub@amazon.com, osalvador@suse.de, mike.kravetz@oracle.com, rientjes@google.com, mark.rutland@arm.com, catalin.marinas@arm.com, james.morse@arm.com Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, duanxiongchun@bytedance.com, fam.zheng@bytedance.com, Muchun Song Subject: [PATCH v2 1/2] arm64: avoid flushing icache multiple times on contiguous HugeTLB Date: Tue, 8 Feb 2022 13:46:31 +0800 Message-Id: <20220208054632.66534-1-songmuchun@bytedance.com> X-Mailer: git-send-email 2.32.0 (Apple Git-132) MIME-Version: 1.0 X-Rspamd-Queue-Id: 78D7A180002 X-Rspam-User: Authentication-Results: imf24.hostedemail.com; dkim=pass header.d=bytedance-com.20210112.gappssmtp.com header.s=20210112 header.b=0HYhkWbJ; spf=pass (imf24.hostedemail.com: domain of songmuchun@bytedance.com designates 209.85.210.179 as permitted sender) smtp.mailfrom=songmuchun@bytedance.com; dmarc=pass (policy=none) header.from=bytedance.com X-Stat-Signature: rwo3f1186sntbgj4oqz94a6qdksxekse X-Rspamd-Server: rspam04 X-HE-Tag: 1644299215-563357 Content-Transfer-Encoding: quoted-printable 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: When a contiguous HugeTLB page is mapped, set_pte_at() will be called CONT_PTES/CONT_PMDS times. Therefore, __sync_icache_dcache() will flush cache multiple times if the page is executable (to ensure the I-D cache coherency). However, the first flushing cache already covers subsequent cache flush operations. So only flusing cache for the head page if it is a HugeTLB page to avoid redundant cache flushing. In the next patch, it is also depends on this change since the tail vmemmap pages of HugeTLB is mapped with read-only meanning only head page struct can be modified. Signed-off-by: Muchun Song --- arch/arm64/mm/flush.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/arm64/mm/flush.c b/arch/arm64/mm/flush.c index 2aaf950b906c..a06c6ac770d4 100644 --- a/arch/arm64/mm/flush.c +++ b/arch/arm64/mm/flush.c @@ -52,6 +52,13 @@ void __sync_icache_dcache(pte_t pte) { struct page *page =3D pte_page(pte); =20 + /* + * HugeTLB pages are always fully mapped, so only setting head page's + * PG_dcache_clean flag is enough. + */ + if (PageHuge(page)) + page =3D compound_head(page); + if (!test_bit(PG_dcache_clean, &page->flags)) { sync_icache_aliases((unsigned long)page_address(page), (unsigned long)page_address(page) + --=20 2.11.0