From nobody Wed Sep 17 15:57:56 2025 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2B81FC4332F for ; Sat, 17 Dec 2022 18:56:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230289AbiLQS4e (ORCPT ); Sat, 17 Dec 2022 13:56:34 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40796 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230031AbiLQSzi (ORCPT ); Sat, 17 Dec 2022 13:55:38 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DB43310FC9; Sat, 17 Dec 2022 10:55:36 -0800 (PST) Date: Sat, 17 Dec 2022 18:55:31 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1671303332; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=QgGIxxjXPXX5AByY57u1zqywk8dbUi7+e1GgB7Rkt0Y=; b=pM+NwnzDN7Jtp0hFFriAUZibIiv0Hf2d8PSVhq0kxwEvJ2DiZ4bsGPNyW9A8XAY2snA/mW H5jC7JBeiOUEqjk7QmvFbbnHgs5eXxuistcc0YGvyOfQSQKtIl62gAjagJ+7++mLSF+EfL GVV9AKl4lA9FH/K+RZNyAq9+dDHGTmxLmNOQRQsto4vzMvi1Qdzi0SE5o2sGGEGJ/+HKfd oezdprsu0nObIeb+/YrIhAroe3jTNdjsDkuDPirwkC8R2+PqesMLeo8cC+qODGxfbeJsve FGxjpLmhP7esdQQmkUUdNnTiPCIW4Ci/KNBgIceH3vBI8q8Oq0UIlkPb0kxP0A== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1671303332; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=QgGIxxjXPXX5AByY57u1zqywk8dbUi7+e1GgB7Rkt0Y=; b=NYXUx1hoQKOjyQpksuBJr0IE29LpapmWP21Udbkj3IC7HYzXUL79nL2Cat9qJxsOoZn6Wx IG+PX1F+hIuxHKCg== From: "tip-bot2 for Peter Zijlstra" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: x86/mm] mm: Remove pointless barrier() after pmdp_get_lockless() Cc: "Peter Zijlstra (Intel)" , x86@kernel.org, linux-kernel@vger.kernel.org MIME-Version: 1.0 Message-ID: <167130333179.4906.5607292265365831847.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the x86/mm branch of tip: Commit-ID: eb780dcae02d5a71e6979aa7b8c708dea8597adf Gitweb: https://git.kernel.org/tip/eb780dcae02d5a71e6979aa7b8c708dea= 8597adf Author: Peter Zijlstra AuthorDate: Fri, 21 Oct 2022 13:47:29 +02:00 Committer: Dave Hansen CommitterDate: Thu, 15 Dec 2022 10:37:27 -08:00 mm: Remove pointless barrier() after pmdp_get_lockless() pmdp_get_lockless() should itself imply any ordering required. Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20221022114425.298833095%40infradead.org --- mm/hmm.c | 1 - mm/vmscan.c | 3 --- 2 files changed, 4 deletions(-) diff --git a/mm/hmm.c b/mm/hmm.c index 39cf50d..601a99c 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -362,7 +362,6 @@ again: * values. */ pmd =3D pmdp_get_lockless(pmdp); - barrier(); if (!pmd_devmap(pmd) && !pmd_trans_huge(pmd)) goto again; =20 diff --git a/mm/vmscan.c b/mm/vmscan.c index 88ef873..4936a88 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -4041,9 +4041,6 @@ restart: for (i =3D pmd_index(start), addr =3D start; addr !=3D end; i++, addr =3D= next) { pmd_t val =3D pmdp_get_lockless(pmd + i); =20 - /* for pmdp_get_lockless() */ - barrier(); - next =3D pmd_addr_end(addr, end); =20 if (!pmd_present(val) || is_huge_zero_pmd(val)) {