From patchwork Mon May 29 06:14:48 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hugh Dickins X-Patchwork-Id: 1786943 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=lists.ozlabs.org (client-ip=2404:9400:2:0:216:3eff:fee1:b9f1; helo=lists.ozlabs.org; envelope-from=linuxppc-dev-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org; receiver=) Authentication-Results: legolas.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=google.com header.i=@google.com header.a=rsa-sha256 header.s=20221208 header.b=j75/ucEx; dkim-atps=neutral Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2404:9400:2:0:216:3eff:fee1:b9f1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-384) server-digest SHA384) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4QV4yM41wvz20Q4 for ; Mon, 29 May 2023 16:15:23 +1000 (AEST) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4QV4yL6zPGz3f8h for ; Mon, 29 May 2023 16:15:22 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=google.com header.i=@google.com header.a=rsa-sha256 header.s=20221208 header.b=j75/ucEx; dkim-atps=neutral X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=google.com (client-ip=2607:f8b0:4864:20::1129; helo=mail-yw1-x1129.google.com; envelope-from=hughd@google.com; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=google.com header.i=@google.com header.a=rsa-sha256 header.s=20221208 header.b=j75/ucEx; dkim-atps=neutral Received: from mail-yw1-x1129.google.com (mail-yw1-x1129.google.com [IPv6:2607:f8b0:4864:20::1129]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4QV4y05TXKz3bTf for ; Mon, 29 May 2023 16:15:04 +1000 (AEST) Received: by mail-yw1-x1129.google.com with SMTP id 00721157ae682-565d354b59fso21829237b3.0 for ; Sun, 28 May 2023 23:15:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1685340901; x=1687932901; h=mime-version:references:message-id:in-reply-to:subject:cc:to:from :date:from:to:cc:subject:date:message-id:reply-to; bh=2Xgtva00uaRjPQjQYWCbyYlUVerqtzlz4H3/JM5nRsA=; b=j75/ucEx6oo4OkFwpLoopPUGefT5zRQ/GQSssdYFJ4lLRni3rLEVhCMo1e8jwYMVcb YP6Bm+ySwzQyzGGQM2rSRov76G9UQ/Tn5RA33SDKqUYCIvPra4wwNlCuRu98iddHbdYN EF4ZzSOFNLEo4zXasuFIAULbNX6r1iMaUqjVeX4Zi3vuHqsR+CvgEyNVfPdXCJfUki2B 3dBz1c7QLHmuXQ+aR4qL+wJWgzXAMcn6OOeaRV4ZdMMOf1AGowm+XIRkGpuH6QAGrUcE pfw/89xaKUYoO8gOTy9XVNliAthq+Njc/D/eHcTCmEi6RvCXrpEvwwxwM3i0HwRhfzXq 7JqQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1685340901; x=1687932901; h=mime-version:references:message-id:in-reply-to:subject:cc:to:from :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=2Xgtva00uaRjPQjQYWCbyYlUVerqtzlz4H3/JM5nRsA=; b=S7qZhP+I651SIfyM1F8dQ2YjX/iyCpFz1OLNaDtNkFTPxinHfJXJo+o36tYnJ/6W8U 3CJRm1aYM2+Pe9qQAIXcFS+lWlTLv8xDedBj+qI20zo8PwU2g6P/S3RASk2FuZ5QCGXe KguGyHX4nvOLLEvUGAEZ+jyGOBcJ/DacuKKJ+myA+gomZI6m2BViaALnSUUgv6IwQ+wm LZXTy1wLROuI6BeG1GGGUTH0CduxVmvJmjDq2X8fK5uiJrX/X+eRvLM1QCJfUMtBRThD /z2TrKHrB5IBVT3Vlb49Ms/nb4IcbqDTkAk2XlxkoFUhk185UL5qdjSKmXJ5YT4oURdk N7QQ== X-Gm-Message-State: AC+VfDz43iZ8A67tWx7S2/jGe49jqh6NA5XW2h6UAMFRxi/FCpFLX3Ux 5nlU/SuxERzWEkP2vsm+LltdQA== X-Google-Smtp-Source: ACHHUZ676xJPstkLOqdersuTwpjuuB4a5YN7mGCxCUJRDLUIc17B3O2mtdL/MxS8/JJgtz6rWj3hTw== X-Received: by 2002:a0d:e685:0:b0:55a:30f5:3d65 with SMTP id p127-20020a0de685000000b0055a30f53d65mr12605725ywe.41.1685340901250; Sun, 28 May 2023 23:15:01 -0700 (PDT) Received: from ripple.attlocal.net (172-10-233-147.lightspeed.sntcca.sbcglobal.net. [172.10.233.147]) by smtp.gmail.com with ESMTPSA id z7-20020a81a247000000b00560c2e3ec63sm3404765ywg.77.2023.05.28.23.14.57 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 28 May 2023 23:15:00 -0700 (PDT) Date: Sun, 28 May 2023 23:14:48 -0700 (PDT) From: Hugh Dickins X-X-Sender: hugh@ripple.attlocal.net To: Andrew Morton Subject: [PATCH 01/12] mm/pgtable: add rcu_read_lock() and rcu_read_unlock()s In-Reply-To: <35e983f5-7ed3-b310-d949-9ae8b130cdab@google.com> Message-ID: <88c445ae-552-5243-31a4-2674bac62d4d@google.com> References: <35e983f5-7ed3-b310-d949-9ae8b130cdab@google.com> MIME-Version: 1.0 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Miaohe Lin , David Hildenbrand , Peter Zijlstra , Yang Shi , Peter Xu , Song Liu , sparclinux@vger.kernel.org, Alexander Gordeev , Claudio Imbrenda , Will Deacon , linux-s390@vger.kernel.org, Yu Zhao , Ira Weiny , Alistair Popple , Russell King , Matthew Wilcox , Steven Price , Christoph Hellwig , Jason Gunthorpe , "Aneesh Kumar K.V" , Axel Rasmussen , Christian Borntraeger , Thomas Hellstrom , Ralph Campbell , Pasha Tatashin , Anshuman Khandual , Heiko Ca rstens , Qi Zheng , Suren Baghdasaryan , linux-arm-kernel@lists.infradead.org, SeongJae Park , Jann Horn , linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, "Kirill A. Shutemov" , Naoya Horiguchi , linux-kernel@vger.kernel.org, Minchan Kim , Mike Rapoport , Mel Gorman , "David S. Miller" , Zack Rusin , Mike Kravetz Errors-To: linuxppc-dev-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" Before putting them to use (several commits later), add rcu_read_lock() to pte_offset_map(), and rcu_read_unlock() to pte_unmap(). Make this a separate commit, since it risks exposing imbalances: prior commits have fixed all the known imbalances, but we may find some have been missed. Signed-off-by: Hugh Dickins --- include/linux/pgtable.h | 4 ++-- mm/pgtable-generic.c | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h index a1326e61d7ee..8b0fc7fdc46f 100644 --- a/include/linux/pgtable.h +++ b/include/linux/pgtable.h @@ -99,7 +99,7 @@ static inline pte_t *pte_offset_kernel(pmd_t *pmd, unsigned long address) ((pte_t *)kmap_local_page(pmd_page(*(pmd))) + pte_index((address))) #define pte_unmap(pte) do { \ kunmap_local((pte)); \ - /* rcu_read_unlock() to be added later */ \ + rcu_read_unlock(); \ } while (0) #else static inline pte_t *__pte_map(pmd_t *pmd, unsigned long address) @@ -108,7 +108,7 @@ static inline pte_t *__pte_map(pmd_t *pmd, unsigned long address) } static inline void pte_unmap(pte_t *pte) { - /* rcu_read_unlock() to be added later */ + rcu_read_unlock(); } #endif diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c index c7ab18a5fb77..674671835631 100644 --- a/mm/pgtable-generic.c +++ b/mm/pgtable-generic.c @@ -236,7 +236,7 @@ pte_t *__pte_offset_map(pmd_t *pmd, unsigned long addr, pmd_t *pmdvalp) { pmd_t pmdval; - /* rcu_read_lock() to be added later */ + rcu_read_lock(); pmdval = pmdp_get_lockless(pmd); if (pmdvalp) *pmdvalp = pmdval; @@ -250,7 +250,7 @@ pte_t *__pte_offset_map(pmd_t *pmd, unsigned long addr, pmd_t *pmdvalp) } return __pte_map(&pmdval, addr); nomap: - /* rcu_read_unlock() to be added later */ + rcu_read_unlock(); return NULL; }