From patchwork Mon Feb 15 16:13:35 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pasha Tatashin X-Patchwork-Id: 12088879 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=-13.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 71AF7C43332 for ; Mon, 15 Feb 2021 16:18:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4EBCB64DEE for ; Mon, 15 Feb 2021 16:18:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230425AbhBOQSi (ORCPT ); Mon, 15 Feb 2021 11:18:38 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48062 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231950AbhBOQOd (ORCPT ); Mon, 15 Feb 2021 11:14:33 -0500 Received: from mail-qk1-x72c.google.com (mail-qk1-x72c.google.com [IPv6:2607:f8b0:4864:20::72c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9E59CC0613D6 for ; Mon, 15 Feb 2021 08:13:52 -0800 (PST) Received: by mail-qk1-x72c.google.com with SMTP id r77so6774894qka.12 for ; Mon, 15 Feb 2021 08:13:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=soleen.com; s=google; h=from:to:subject:date:message-id:mime-version :content-transfer-encoding; bh=EgOcbWVlXEaTgKR2YO46uJEZBiJ6ZIhzWJFxuAbweaw=; b=cLqsFxDnVUK7Y9ck/9he2hDj69MH1f8OnnYTThtorOSvC+8klrQ4URYBDdvymVIvl2 hERmNfmVceoEMVPp1G2KkiT/VCrvoDAxz5FT/DAcUoVpLUdkr5MqD12G+3BfwNEZCjOJ Cx+sSKpWKQubyXLM0wqECyXmo3Wo8qno269R73OwnnTUQo1ucJZxeEXgONvLB3jt/1dY etUFBRiRPGsWvGbOgqI1I5wE0H7oGpxrMlcWMzCBHakPIhyDn0uE5/qHRkMaDlpSlU65 q0LTXG44zleaLM2brFtYb3WRlE0JBl8F6B4kXkm6eqGRDgFGa7ilWGpdS8qj3kPBWgrm eBOA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id:mime-version :content-transfer-encoding; bh=EgOcbWVlXEaTgKR2YO46uJEZBiJ6ZIhzWJFxuAbweaw=; b=R8EGD95MjAZRxodeKg8Eg5alsPyHbma1Ip1K+pl4SyNvsFt6e8LGvNxmjBYHlrbw5n qh4tjHh4Feoa9Tci8M69tLUcaypf2ONnVS5Ldl4EOPQvcq45XwaWiGLQ1GranqNUGbHL ffDNK8XN97G0A/1AYWiQYHueCtDNTL0ogIcSAX1QvGiMGj7kANMmgjQ8qC+QPfbbHFVJ 0H4kT/DKgBHMTDvhC37Q0f+3SeXozesOFS8L/WFEJ171E5z9OnxzvAYTnGZndejNWAIt figOuBdmZpGExhSAIszW6PcyI7XIPJvJexGZKt30gn1Ymwos0vOk5kdWKd+IOOaUIJIN oQUA== X-Gm-Message-State: AOAM530qFuQtsO0GOr43za4kah3OPVWdR6OJuJfnwZ2zI/dWMR3JUAwn JDvWsN/lQcUpOAddpvGgRyXtMQ== X-Google-Smtp-Source: ABdhPJxcFlGOXp1G4eLBqTJDnimeoLjm6V7Zt5zCfBSYhgAGdK3sw96DHL1ley2e0Eb8rfmhWqxFJA== X-Received: by 2002:a37:a191:: with SMTP id k139mr14960124qke.61.1613405631689; Mon, 15 Feb 2021 08:13:51 -0800 (PST) Received: from localhost.localdomain (c-73-69-118-222.hsd1.nh.comcast.net. [73.69.118.222]) by smtp.gmail.com with ESMTPSA id u7sm10909213qta.75.2021.02.15.08.13.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 15 Feb 2021 08:13:50 -0800 (PST) From: Pavel Tatashin To: pasha.tatashin@soleen.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, akpm@linux-foundation.org, vbabka@suse.cz, mhocko@suse.com, david@redhat.com, osalvador@suse.de, dan.j.williams@intel.com, sashal@kernel.org, tyhicks@linux.microsoft.com, iamjoonsoo.kim@lge.com, mike.kravetz@oracle.com, rostedt@goodmis.org, mingo@redhat.com, jgg@ziepe.ca, peterz@infradead.org, mgorman@suse.de, willy@infradead.org, rientjes@google.com, jhubbard@nvidia.com, linux-doc@vger.kernel.org, ira.weiny@intel.com, linux-kselftest@vger.kernel.org, jmorris@namei.org Subject: [PATCH v11 00/14] prohibit pinning pages in ZONE_MOVABLE Date: Mon, 15 Feb 2021 11:13:35 -0500 Message-Id: <20210215161349.246722-1-pasha.tatashin@soleen.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Changelog --------- v11 - Another build fix reported by robot on i386: moved is_pinnable_page() below set_page_section() in linux/mm.h v10 - Fixed !CONFIG_MMU compiler issues by adding is_zero_pfn() stub. v9 - Renamed gpf_to_alloc_flags() to gfp_to_alloc_flags_cma(); thanks Lecopzer Chen for noticing. - Fixed warning reported scripts/checkpatch.pl: "Logical continuations should be on the previous line" v8 - Added reviewed by's from John Hubbard - Fixed subjects for selftests patches - Moved zero page check inside is_pinnable_page() as requested by Jason Gunthorpe. v7 - Added reviewed-by's - Fixed a compile bug on non-mmu builds reported by robot v6 Small update, but I wanted to send it out quicker, as it removes a controversial patch and replaces it with something sane. - Removed forcing FOLL_WRITE for longterm gup, instead added a patch to skip zero pages during migration. - Added reviewed-by's and minor log changes. v5 - Added the following patches to the beginning of series, which are fixes to the other existing problems with CMA migration code: mm/gup: check every subpage of a compound page during isolation mm/gup: return an error on migration failure mm/gup: check for isolation errors also at the beginning of series mm/gup: do not allow zero page for pinned pages - remove .gfp_mask/.reclaim_idx changes from mm/vmscan.c - update movable zone header comment in patch 8 instead of patch 3, fix the comment - Added acked, sign-offs - Updated commit logs based on feedback - Addressed issues reported by Michal and Jason. - Remove: #define PINNABLE_MIGRATE_MAX 10 #define PINNABLE_ISOLATE_MAX 100 Instead: fail on the first migration failure, and retry isolation forever as their failures are transient. - In self-set addressed some of the comments from John Hubbard, updated commit logs, and added comments. Renamed gup->flags with gup->test_flags. v4 - Address page migration comments. New patch: mm/gup: limit number of gup migration failures, honor failures Implements the limiting number of retries for migration failures, and also check for isolation failures. Added a test case into gup_test to verify that pages never long-term pinned in a movable zone, and also added tests to fault both in kernel and in userland. v3 - Merged with linux-next, which contains clean-up patch from Jason, therefore this series is reduced by two patches which did the same thing. v2 - Addressed all review comments - Added Reviewed-by's. - Renamed PF_MEMALLOC_NOMOVABLE to PF_MEMALLOC_PIN - Added is_pinnable_page() to check if page can be longterm pinned - Fixed gup fast path by checking is_in_pinnable_zone() - rename cma_page_list to movable_page_list - add a admin-guide note about handling pinned pages in ZONE_MOVABLE, updated caveat about pinned pages from linux/mmzone.h - Move current_gfp_context() to fast-path --------- When page is pinned it cannot be moved and its physical address stays the same until pages is unpinned. This is useful functionality to allows userland to implementation DMA access. For example, it is used by vfio in vfio_pin_pages(). However, this functionality breaks memory hotplug/hotremove assumptions that pages in ZONE_MOVABLE can always be migrated. This patch series fixes this issue by forcing new allocations during page pinning to omit ZONE_MOVABLE, and also to migrate any existing pages from ZONE_MOVABLE during pinning. It uses the same scheme logic that is currently used by CMA, and extends the functionality for all allocations. For more information read the discussion [1] about this problem. [1] https://lore.kernel.org/lkml/CA+CK2bBffHBxjmb9jmSKacm0fJMinyt3Nhk8Nx6iudcQSj80_w@mail.gmail.com Previous versions: v1 https://lore.kernel.org/lkml/20201202052330.474592-1-pasha.tatashin@soleen.com v2 https://lore.kernel.org/lkml/20201210004335.64634-1-pasha.tatashin@soleen.com v3 https://lore.kernel.org/lkml/20201211202140.396852-1-pasha.tatashin@soleen.com v4 https://lore.kernel.org/lkml/20201217185243.3288048-1-pasha.tatashin@soleen.com v5 https://lore.kernel.org/lkml/20210119043920.155044-1-pasha.tatashin@soleen.com v6 https://lore.kernel.org/lkml/20210120014333.222547-1-pasha.tatashin@soleen.com v7 https://lore.kernel.org/lkml/20210122033748.924330-1-pasha.tatashin@soleen.com v8 https://lore.kernel.org/lkml/20210125194751.1275316-1-pasha.tatashin@soleen.com v9 https://lore.kernel.org/lkml/20210201153827.444374-1-pasha.tatashin@soleen.com v10 https://lore.kernel.org/lkml/20210211162427.618913-1-pasha.tatashin@soleen.com Pavel Tatashin (14): mm/gup: don't pin migrated cma pages in movable zone mm/gup: check every subpage of a compound page during isolation mm/gup: return an error on migration failure mm/gup: check for isolation errors mm cma: rename PF_MEMALLOC_NOCMA to PF_MEMALLOC_PIN mm: apply per-task gfp constraints in fast path mm: honor PF_MEMALLOC_PIN for all movable pages mm/gup: do not migrate zero page mm/gup: migrate pinned pages out of movable zone memory-hotplug.rst: add a note about ZONE_MOVABLE and page pinning mm/gup: change index type to long as it counts pages mm/gup: longterm pin migration cleanup selftests/vm: gup_test: fix test flag selftests/vm: gup_test: test faulting in kernel, and verify pinnable pages .../admin-guide/mm/memory-hotplug.rst | 9 + include/linux/migrate.h | 1 + include/linux/mm.h | 19 ++ include/linux/mmzone.h | 13 +- include/linux/pgtable.h | 12 ++ include/linux/sched.h | 2 +- include/linux/sched/mm.h | 27 +-- include/trace/events/migrate.h | 3 +- mm/gup.c | 174 ++++++++---------- mm/gup_test.c | 29 +-- mm/gup_test.h | 3 +- mm/hugetlb.c | 4 +- mm/page_alloc.c | 33 ++-- tools/testing/selftests/vm/gup_test.c | 36 +++- 14 files changed, 208 insertions(+), 157 deletions(-)