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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3501CC636CC for ; Thu, 16 Feb 2023 05:20:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229712AbjBPFUQ (ORCPT ); Thu, 16 Feb 2023 00:20:16 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46124 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229627AbjBPFTV (ORCPT ); Thu, 16 Feb 2023 00:19:21 -0500 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B98BD42DCE for ; Wed, 15 Feb 2023 21:18:45 -0800 (PST) Received: by mail-yb1-xb4a.google.com with SMTP id k9-20020a25bec9000000b00944353b6a81so863507ybm.7 for ; Wed, 15 Feb 2023 21:18:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=65rn53nYPCehqawxI5VHHUH5OXR7IFklQh11X90VOGk=; b=ngrSSnFGdDPlYz5zuJYWd2ZcJdDDxwAT/RtnIL5xzVfAFVgHCKIj7A9xwEDcTyX2aB 3vsZSlkeyPVpcwi1aa9l93eu/icfxKL0DIaqQVOS2lNklMJwu2jpUpq532q1GD3mJcXZ OYyJWX25F7RdsRsm0bO+ULQDs6kU+hJx2yHcqT8VTisE8SVpLjiLy4deYJxyu/llv5yd uNDnBwf4OPlsNNTMONtuv4dnuvjdk8hbLw2jK3U2tc3OA2ZTvVJ3/lGJPyy4Jcy7H5Vt +ZqHtuuBA7mxmkHLm02ywaCux2tqtjmQCbr0/F6E0nSC73lfB2u+G7wX3tsYtQZiJlY+ ecqA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=65rn53nYPCehqawxI5VHHUH5OXR7IFklQh11X90VOGk=; b=If914xyNZ6E6JKn7JwPiydaFH9m235YeOJJjL/0kh0TjuFOcDzgmXtRrXJhjCMHDBo SewVQlA9iQFZBoC2ydiSQscZ46Vt51irOxbqdbPemMpg6t4QQ9fjhsRimf33SdhFuSVw rE/6vInHrhZLQcPnU590LauLe1Vup2MsFv1Rnb5q8DVXWBZ3YJKLkF37lWqgUfHm9uTx Z3qzTY3yMkJQ4I4Mw9VJOc1bKaiA5eGnJTVjUUrbdkUMH12hp1OWvbTDI/KEhG2nMZQL 58Rs2Fp9jmqQiE4dyZHQS0WDg8/zpwDvWr+KZt4LjyoPcPcbv42jkbo2eDdN9zBK7AwB EM+Q== X-Gm-Message-State: AO0yUKUKFoUUb+u5EjrxgeHJRO/K9ZmhN9fdKH/eDARrjH331nWPjWuO GQcXRMn9bh/ItRfqN+A5OKCVL+/6IAE= X-Google-Smtp-Source: AK7set9eBfEal0C1jR4VjCmFFWO3/hvdavzvid6pMzzd4bvHowMVw43Kn34On8e4ZBDtcDdaQHGRoUI6tN4= X-Received: from surenb-desktop.mtv.corp.google.com ([2620:15c:211:200:f781:d5ed:1806:6ebb]) (user=surenb job=sendgmr) by 2002:a81:b704:0:b0:52b:fcf0:4fd1 with SMTP id v4-20020a81b704000000b0052bfcf04fd1mr5ywh.1.1676524723168; Wed, 15 Feb 2023 21:18:43 -0800 (PST) Date: Wed, 15 Feb 2023 21:17:35 -0800 In-Reply-To: <20230216051750.3125598-1-surenb@google.com> Mime-Version: 1.0 References: <20230216051750.3125598-1-surenb@google.com> X-Mailer: git-send-email 2.39.1.581.gbfd45094c4-goog Message-ID: <20230216051750.3125598-21-surenb@google.com> Subject: [PATCH v3 20/35] mm: conditionally write-lock VMA in free_pgtables From: Suren Baghdasaryan To: akpm@linux-foundation.org Cc: michel@lespinasse.org, jglisse@google.com, mhocko@suse.com, vbabka@suse.cz, hannes@cmpxchg.org, mgorman@techsingularity.net, dave@stgolabs.net, willy@infradead.org, liam.howlett@oracle.com, peterz@infradead.org, ldufour@linux.ibm.com, paulmck@kernel.org, mingo@redhat.com, will@kernel.org, luto@kernel.org, songliubraving@fb.com, peterx@redhat.com, david@redhat.com, dhowells@redhat.com, hughd@google.com, bigeasy@linutronix.de, kent.overstreet@linux.dev, punit.agrawal@bytedance.com, lstoakes@gmail.com, peterjung1337@gmail.com, rientjes@google.com, chriscli@google.com, axelrasmussen@google.com, joelaf@google.com, minchan@google.com, rppt@kernel.org, jannh@google.com, shakeelb@google.com, tatashin@google.com, edumazet@google.com, gthelen@google.com, gurua@google.com, arjunroy@google.com, soheil@google.com, leewalsh@google.com, posk@google.com, michalechner92@googlemail.com, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, x86@kernel.org, linux-kernel@vger.kernel.org, kernel-team@android.com, Suren Baghdasaryan Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Normally free_pgtables needs to lock affected VMAs except for the case when VMAs were isolated under VMA write-lock. munmap() does just that, isolating while holding appropriate locks and then downgrading mmap_lock and dropping per-VMA locks before freeing page tables. Add a parameter to free_pgtables for such scenario. Signed-off-by: Suren Baghdasaryan --- mm/internal.h | 2 +- mm/memory.c | 6 +++++- mm/mmap.c | 5 +++-- 3 files changed, 9 insertions(+), 4 deletions(-) diff --git a/mm/internal.h b/mm/internal.h index fc01fd092ea5..400c302fbf47 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -105,7 +105,7 @@ void folio_activate(struct folio *folio); void free_pgtables(struct mmu_gather *tlb, struct maple_tree *mt, struct vm_area_struct *start_vma, unsigned long floor, - unsigned long ceiling); + unsigned long ceiling, bool mm_wr_locked); void pmd_install(struct mm_struct *mm, pmd_t *pmd, pgtable_t *pte); struct zap_details; diff --git a/mm/memory.c b/mm/memory.c index f456f3b5049c..8177c59ffd2d 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -348,7 +348,7 @@ void free_pgd_range(struct mmu_gather *tlb, void free_pgtables(struct mmu_gather *tlb, struct maple_tree *mt, struct vm_area_struct *vma, unsigned long floor, - unsigned long ceiling) + unsigned long ceiling, bool mm_wr_locked) { MA_STATE(mas, mt, vma->vm_end, vma->vm_end); @@ -366,6 +366,8 @@ void free_pgtables(struct mmu_gather *tlb, struct maple_tree *mt, * Hide vma from rmap and truncate_pagecache before freeing * pgtables */ + if (mm_wr_locked) + vma_start_write(vma); unlink_anon_vmas(vma); unlink_file_vma(vma); @@ -380,6 +382,8 @@ void free_pgtables(struct mmu_gather *tlb, struct maple_tree *mt, && !is_vm_hugetlb_page(next)) { vma = next; next = mas_find(&mas, ceiling - 1); + if (mm_wr_locked) + vma_start_write(vma); unlink_anon_vmas(vma); unlink_file_vma(vma); } diff --git a/mm/mmap.c b/mm/mmap.c index aaa359a147b2..118b2246bba9 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -2157,7 +2157,8 @@ static void unmap_region(struct mm_struct *mm, struct maple_tree *mt, update_hiwater_rss(mm); unmap_vmas(&tlb, mt, vma, start, end, mm_wr_locked); free_pgtables(&tlb, mt, vma, prev ? prev->vm_end : FIRST_USER_ADDRESS, - next ? next->vm_start : USER_PGTABLES_CEILING); + next ? next->vm_start : USER_PGTABLES_CEILING, + mm_wr_locked); tlb_finish_mmu(&tlb); } @@ -3069,7 +3070,7 @@ void exit_mmap(struct mm_struct *mm) mmap_write_lock(mm); mt_clear_in_rcu(&mm->mm_mt); free_pgtables(&tlb, &mm->mm_mt, vma, FIRST_USER_ADDRESS, - USER_PGTABLES_CEILING); + USER_PGTABLES_CEILING, true); tlb_finish_mmu(&tlb); /* -- 2.39.1