From patchwork Thu Feb 11 16:24:14 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pasha Tatashin X-Patchwork-Id: 12083697 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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 7E62EC433E9 for ; Thu, 11 Feb 2021 16:27:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4AF6F64E92 for ; Thu, 11 Feb 2021 16:27:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231876AbhBKQ1a (ORCPT ); Thu, 11 Feb 2021 11:27:30 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36564 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231915AbhBKQZN (ORCPT ); Thu, 11 Feb 2021 11:25:13 -0500 Received: from mail-qv1-xf2a.google.com (mail-qv1-xf2a.google.com [IPv6:2607:f8b0:4864:20::f2a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D2E86C061788 for ; Thu, 11 Feb 2021 08:24:31 -0800 (PST) Received: by mail-qv1-xf2a.google.com with SMTP id 2so2823005qvd.0 for ; Thu, 11 Feb 2021 08:24:31 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=soleen.com; s=google; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=Eb4Z5OA9Zh686EUEmFFrS5z1Iv7khNETxfPbVyT47Bw=; b=l/VZLQ8IiF9IIVyBOqtHnEGH2KT3DOse3oUidCCmKkGcdaf7QZmZsCP29d1dF1g18t rAghwGOCk+1WBqJn61TdveTUxo3yscxw15XN2DnWOrc0rlpxoqTQVhjvKzfaYqt3i8+8 Xm5ua11oNKU9XyYAlFHQRzpyIXolK47tGgo+ryTw3HXiqK++AEyqaCUlBCc6g4QT7AWE JHS2Yf5XlillyXO2wauFwv1L8p3MN6DSAorqGHe+drg74h0gqpaB7IpJC84f9MFzMR0x sVtgd82vXTCXPo8WPhvShhYsRZ25YDY/VM3K1FDh1/ugiQAOKNT57Zhb+c7v6ZJ7s57G nttw== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=Eb4Z5OA9Zh686EUEmFFrS5z1Iv7khNETxfPbVyT47Bw=; b=ptDskqKSkxPfM/BvRdI58HYa4KrqizPVgwK4XImaFHrvsIvHP5WwHmPrTvYH3oozBS uLVWds9r5QUeOQf/agyf4zrvpPo+XPiLIPqCSLvIZXgAtgt/wXoIJ5+Xvljdzk/nN7FN 9r4qTmB8T15JWewgBrfX5TCildPEmXBf3FQFAy8uO8InZmiuomh8lOBPBZfNf6FlGjkB aaQPdhl8NSZNykPSCQFOzbbWzk+BIif5EhhfHCdlo31zZMOzd7L5BaptqbneDDQFlHJa qYES5g3rlR9SuI69+DlBcXy7AaAZLs9VxypnZTE/w2hLi/XSe87tWCAKMggVvsTmgUSa 4MQA== X-Gm-Message-State: AOAM531Oub4Qqzi436D7of09LCNqg+B0Ox5vGq2HgrgKWdB7Rwu1kAF1 ESZxftaS1jVnZpVwoyLNiM76mQ== X-Google-Smtp-Source: ABdhPJw9rSf4xISC0Xn5LFKiNNWdqZ4YEh2Y2mQpMqsSCVHEgDugx+m0a9VyLYZFGp3Jt0z9q8GiVg== X-Received: by 2002:ad4:4345:: with SMTP id q5mr8526952qvs.61.1613060671144; Thu, 11 Feb 2021 08:24:31 -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 i23sm3831778qtq.42.2021.02.11.08.24.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 11 Feb 2021 08:24:30 -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 v10 01/14] mm/gup: don't pin migrated cma pages in movable zone Date: Thu, 11 Feb 2021 11:24:14 -0500 Message-Id: <20210211162427.618913-2-pasha.tatashin@soleen.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210211162427.618913-1-pasha.tatashin@soleen.com> References: <20210211162427.618913-1-pasha.tatashin@soleen.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org In order not to fragment CMA the pinned pages are migrated. However, they are migrated to ZONE_MOVABLE, which also should not have pinned pages. Remove __GFP_MOVABLE, so pages can be migrated to zones where pinning is allowed. Signed-off-by: Pavel Tatashin Reviewed-by: David Hildenbrand Reviewed-by: John Hubbard Acked-by: Michal Hocko --- mm/gup.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/gup.c b/mm/gup.c index e40579624f10..88441de65e34 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -1555,7 +1555,7 @@ static long check_and_migrate_cma_pages(struct mm_struct *mm, long ret = nr_pages; struct migration_target_control mtc = { .nid = NUMA_NO_NODE, - .gfp_mask = GFP_USER | __GFP_MOVABLE | __GFP_NOWARN, + .gfp_mask = GFP_USER | __GFP_NOWARN, }; check_again: From patchwork Thu Feb 11 16:24:15 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pasha Tatashin X-Patchwork-Id: 12083701 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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 A10E9C433DB for ; Thu, 11 Feb 2021 16:28:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 75EAA64EB9 for ; Thu, 11 Feb 2021 16:28:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231915AbhBKQ1f (ORCPT ); Thu, 11 Feb 2021 11:27:35 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36574 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231167AbhBKQZO (ORCPT ); Thu, 11 Feb 2021 11:25:14 -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 63296C061793 for ; Thu, 11 Feb 2021 08:24:33 -0800 (PST) Received: by mail-qk1-x72c.google.com with SMTP id s77so5709484qke.4 for ; Thu, 11 Feb 2021 08:24:33 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=soleen.com; s=google; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=LL91sOR6eNdLBKKX+cwP2EUL4T0OiDJ4l8AEtucy7F0=; b=Cu6OHd4IUjAcSplCwvpYfXX30K5w7v6nYpY1ArywdPsTP+EXS6Oaiocsonki3raoXR SLxlbJk5ql00SZPeoI3Tl2LzMaXU1I5Cquh/q5MCHSMzr8UDfoCLn0igPWuGMbHc6ckR /GXj7V2jbEsnNl8OtcHyY80k3q6kHFSgEpAWWE3hnTxUPdV7hKwxqU0vPufG77ip5IeD 1nvTBp2ZkabycEZ954AkMsimOJGZPux+lDVJKPXX9/1i6MxZrhfky6eJVJZiVQ2kb1qN u7xl4XzcGzgfKDZdwz6mF1NZca6lQca5gq1Kcfnh16KgeVBRwLxlSWbyGeLTQgvMjshv 5t0Q== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=LL91sOR6eNdLBKKX+cwP2EUL4T0OiDJ4l8AEtucy7F0=; b=n6KsHcl5zSB2d7MYtAq3OhW9GCawdkpQrrHBPlXOUgEQFYi3AgZJkBny6kSL+L7g5K W0LKf8zUhVQ7voYX3PjN0xnxHAvrGxLMFtNiDKSmeP8C5rZkZOAKsoYdDC979P5BWcdl hfcKD1sogf1bDDt1bNnoOLpIiariwhWMvACIXYdhpiDyXu2rzZlkK77c8EuTsNjkYdaS 8tyjlc71tToaASAxYq4WCKfUMTvi8FGKtYYYAU4lUoMZ/N+BPcZ4nF5OyTvwSyMQ7s1t dCAzssoufgOeobS2Zy+bhmaymDRg5NAn6e/EFIK2D5zGmlbrsI3QNTulQSjFxCV1HEKO D1CQ== X-Gm-Message-State: AOAM5303IdhSE5uZe0XMKvlqdJnAz5V/ar1B4NE6gH4srRdEZoTRMlXz TH4UFYs3L9f5eEBORfROG3BdtA== X-Google-Smtp-Source: ABdhPJwOvjkc4WjRekXFLBt/hqaYUExG2N08qrgzJfAlZ/EDH7efpQkM+/m48smbKkvu5kmAAyDM8A== X-Received: by 2002:a05:620a:166a:: with SMTP id d10mr8596059qko.213.1613060672602; Thu, 11 Feb 2021 08:24:32 -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 i23sm3831778qtq.42.2021.02.11.08.24.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 11 Feb 2021 08:24:32 -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 v10 02/14] mm/gup: check every subpage of a compound page during isolation Date: Thu, 11 Feb 2021 11:24:15 -0500 Message-Id: <20210211162427.618913-3-pasha.tatashin@soleen.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210211162427.618913-1-pasha.tatashin@soleen.com> References: <20210211162427.618913-1-pasha.tatashin@soleen.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org When pages are isolated in check_and_migrate_movable_pages() we skip compound number of pages at a time. However, as Jason noted, it is not necessary correct that pages[i] corresponds to the pages that we skipped. This is because it is possible that the addresses in this range had split_huge_pmd()/split_huge_pud(), and these functions do not update the compound page metadata. The problem can be reproduced if something like this occurs: 1. User faulted huge pages. 2. split_huge_pmd() was called for some reason 3. User has unmapped some sub-pages in the range 4. User tries to longterm pin the addresses. The resulting pages[i] might end-up having pages which are not compound size page aligned. Fixes: aa712399c1e8 ("mm/gup: speed up check_and_migrate_cma_pages() on huge page") Reported-by: Jason Gunthorpe Signed-off-by: Pavel Tatashin Reviewed-by: Jason Gunthorpe --- mm/gup.c | 19 +++++++------------ 1 file changed, 7 insertions(+), 12 deletions(-) diff --git a/mm/gup.c b/mm/gup.c index 88441de65e34..1f73cbf7fb37 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -1548,26 +1548,23 @@ static long check_and_migrate_cma_pages(struct mm_struct *mm, unsigned int gup_flags) { unsigned long i; - unsigned long step; bool drain_allow = true; bool migrate_allow = true; LIST_HEAD(cma_page_list); long ret = nr_pages; + struct page *prev_head, *head; struct migration_target_control mtc = { .nid = NUMA_NO_NODE, .gfp_mask = GFP_USER | __GFP_NOWARN, }; check_again: - for (i = 0; i < nr_pages;) { - - struct page *head = compound_head(pages[i]); - - /* - * gup may start from a tail page. Advance step by the left - * part. - */ - step = compound_nr(head) - (pages[i] - head); + prev_head = NULL; + for (i = 0; i < nr_pages; i++) { + head = compound_head(pages[i]); + if (head == prev_head) + continue; + prev_head = head; /* * If we get a page from the CMA zone, since we are going to * be pinning these entries, we might as well move them out @@ -1591,8 +1588,6 @@ static long check_and_migrate_cma_pages(struct mm_struct *mm, } } } - - i += step; } if (!list_empty(&cma_page_list)) { From patchwork Thu Feb 11 16:24:16 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pasha Tatashin X-Patchwork-Id: 12083703 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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 30149C433E6 for ; Thu, 11 Feb 2021 16:28:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0636C64E92 for ; Thu, 11 Feb 2021 16:28:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231945AbhBKQ1k (ORCPT ); Thu, 11 Feb 2021 11:27:40 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36588 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232008AbhBKQZR (ORCPT ); Thu, 11 Feb 2021 11:25:17 -0500 Received: from mail-qk1-x730.google.com (mail-qk1-x730.google.com [IPv6:2607:f8b0:4864:20::730]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 23C73C0617A9 for ; Thu, 11 Feb 2021 08:24:35 -0800 (PST) Received: by mail-qk1-x730.google.com with SMTP id h8so5703630qkk.6 for ; Thu, 11 Feb 2021 08:24:35 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=soleen.com; s=google; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=3YGhOpgTUnoFUZs688fDjhyQOugw+M5mTwB+lsQcb5I=; b=o+yT0iXdBFV800Ng44S1WVngLnEx6WCic9zMtJB1wm+4xQZGNvyzm0ZeSKiPypriL4 ptcoRie3RdwdjYq0uvrNJwyokXgKEX8YRuGP9uTqpW5Df6MWRCoGllBnhdbj9nKOKZXI Z3FTCPmgWAHnIj6UdHe1V1prDVaBUwkVEUIIkJXxchk9pzM88eOuB3dvd7xXGroMcAc6 UoPJ9r/E01wdE4SC/gUyYf+SyYX8Ii1zA9TxCEQex9T7P+5xmjLqQfqlyz50BpY1pjkn L2ktEgolhpYdlvz4IWMmPpLnV7SHaPwC8KVAvS4dgpqXP4pGXntiAE6vPYuvudxqeZUo 0JZQ== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=3YGhOpgTUnoFUZs688fDjhyQOugw+M5mTwB+lsQcb5I=; b=Pf9Edjlg8ZA/yewHnkHpkOCB6xhEbpXq32/b3rCsuYObG/loXEEUO7k6L+0ZcH0tej XoLAuKyzimUJTd7CLtcAnwc5j+tCCAlIWmP9n52lBoMlE+RGeqBiQmyhNAYtzH2VwDxz ZCvdwxZ2gEkHEtQob6MCW6+VxtQIjVVcpoHUH2m6m8N1lnD0/VDOLJXC1Nu2NgjtOTJd SEN6A5xYO+jVa1yb/qP+fPidje7yZTE91AXWu96jxiE31MD+w5RVqaMYY4zQuRO8b2/8 vllYlo+gipjgKjgNYYW4ggwt4AIn0gTxKXpb+NQn69REV7mZ8+TROIGBES0GbezXebSf HFbA== X-Gm-Message-State: AOAM5301l5mNi52Ti3k2E2Uxe1r2ra2iykJMSVp4e5kFR4QoBz3ce6rl guTikMBUyzDHiYo74cSPXmzogA== X-Google-Smtp-Source: ABdhPJwnKajWFyfDuBVS+SGOOtyiqDkHprT6U4jwJWb/Dszw7JzrRM/J6ktUBAouVL19l73ROOoTFg== X-Received: by 2002:a05:620a:13ae:: with SMTP id m14mr8944398qki.35.1613060674348; Thu, 11 Feb 2021 08:24:34 -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 i23sm3831778qtq.42.2021.02.11.08.24.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 11 Feb 2021 08:24:33 -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 v10 03/14] mm/gup: return an error on migration failure Date: Thu, 11 Feb 2021 11:24:16 -0500 Message-Id: <20210211162427.618913-4-pasha.tatashin@soleen.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210211162427.618913-1-pasha.tatashin@soleen.com> References: <20210211162427.618913-1-pasha.tatashin@soleen.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org When migration failure occurs, we still pin pages, which means that we may pin CMA movable pages which should never be the case. Instead return an error without pinning pages when migration failure happens. No need to retry migrating, because migrate_pages() already retries 10 times. Signed-off-by: Pavel Tatashin Reviewed-by: Jason Gunthorpe --- mm/gup.c | 17 +++++++---------- 1 file changed, 7 insertions(+), 10 deletions(-) diff --git a/mm/gup.c b/mm/gup.c index 1f73cbf7fb37..eb8c39953d53 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -1549,7 +1549,6 @@ static long check_and_migrate_cma_pages(struct mm_struct *mm, { unsigned long i; bool drain_allow = true; - bool migrate_allow = true; LIST_HEAD(cma_page_list); long ret = nr_pages; struct page *prev_head, *head; @@ -1600,17 +1599,15 @@ static long check_and_migrate_cma_pages(struct mm_struct *mm, for (i = 0; i < nr_pages; i++) put_page(pages[i]); - if (migrate_pages(&cma_page_list, alloc_migration_target, NULL, - (unsigned long)&mtc, MIGRATE_SYNC, MR_CONTIG_RANGE)) { - /* - * some of the pages failed migration. Do get_user_pages - * without migration. - */ - migrate_allow = false; - + ret = migrate_pages(&cma_page_list, alloc_migration_target, + NULL, (unsigned long)&mtc, MIGRATE_SYNC, + MR_CONTIG_RANGE); + if (ret) { if (!list_empty(&cma_page_list)) putback_movable_pages(&cma_page_list); + return ret > 0 ? -ENOMEM : ret; } + /* * We did migrate all the pages, Try to get the page references * again migrating any new CMA pages which we failed to isolate @@ -1620,7 +1617,7 @@ static long check_and_migrate_cma_pages(struct mm_struct *mm, pages, vmas, NULL, gup_flags); - if ((ret > 0) && migrate_allow) { + if (ret > 0) { nr_pages = ret; drain_allow = true; goto check_again; From patchwork Thu Feb 11 16:24:17 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pasha Tatashin X-Patchwork-Id: 12083699 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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 87901C433E0 for ; Thu, 11 Feb 2021 16:28:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5DE7E64EAC for ; Thu, 11 Feb 2021 16:28:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231961AbhBKQ1h (ORCPT ); Thu, 11 Feb 2021 11:27:37 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36594 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232029AbhBKQZW (ORCPT ); Thu, 11 Feb 2021 11:25:22 -0500 Received: from mail-qk1-x733.google.com (mail-qk1-x733.google.com [IPv6:2607:f8b0:4864:20::733]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 91968C0617AA for ; Thu, 11 Feb 2021 08:24:36 -0800 (PST) Received: by mail-qk1-x733.google.com with SMTP id r77so5675880qka.12 for ; Thu, 11 Feb 2021 08:24:36 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=soleen.com; s=google; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=+uM7iGhfnoUeI1t0IUaH+Vl0pOebgnmrqgW4IescHko=; b=YyEw3VerwiWUlTZ//FfQlXGigghHmwC0XIsSkbgjnM/tN1cGCg7L6d1kxsu6VLbwDz Vi6CMBYbI3d+Io8phkGGDLU6axcDOyngmDu0fRPvuq0KiqOaZkbCBa8mHYRm6aPTvYtl 6kkDzuUtLq9my2EJnaDnoF/0PyshrMdwEhmQ9C+jWIRVhCSAhY5tEG/OfqLUJ+HjjQPM /fNiZUUK1HRedq6RYs9Pjq6EKVMJXNF1T0r6VNA1V7KKAZutRcayLaxTk1lv0xlpcmUY vkIa6OCUPRuMAUQLIyRiQIxBXdD3ql6SvKWEWjri5HfxvWELIzcYl/TM6WxmDU/0BtcP s2Xw== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=+uM7iGhfnoUeI1t0IUaH+Vl0pOebgnmrqgW4IescHko=; b=ZL/eTSL6EMLYe+mDUEhY5SOBaV021p4wslR5ElRDzJyhWKnu1rWgGEH6o1vRBEdUkY tnAdVGyJ/dXEql1QXZxmZqoiIEA7I7zIXIKK3i5qn+nxs3V+LR1h7c6UBw5hpv7Yx/Gm 6H+Wa41v+wpCOQcO+P/LnBLH+uZDD4A/OSrQB/EHY7o2jyXHA8AhHLfT56opkS8EGLGb SLS51DQKXihaccMGKK8DiMnf8IWQ+aMBeCxz8PCIpJUPmrhO+c9lSREXZHxx6ySGIWUN 8GRqf31acK7Sn1w3lPQk/Z0CX6yAEV9lo/kKxgYWWNLzyrx9X2zo2UVjcm3RfKVGDxH7 L2HA== X-Gm-Message-State: AOAM533AmTLMD/iyUOvRLPgTJDOiokw/x/6nd7BjiTGnlQ0zH7HY8gfb uA7CJuEcyJi9xzj4rLdiu6Oj7g== X-Google-Smtp-Source: ABdhPJxljTO3Qf3zp+sZkqxd4q6BMw4nfs2iDB2ViVZwrMwjGf1770lvI8Ep6TC0EFBI/13mBrcNVg== X-Received: by 2002:a05:620a:16ab:: with SMTP id s11mr2477523qkj.106.1613060675829; Thu, 11 Feb 2021 08:24:35 -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 i23sm3831778qtq.42.2021.02.11.08.24.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 11 Feb 2021 08:24:35 -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 v10 04/14] mm/gup: check for isolation errors Date: Thu, 11 Feb 2021 11:24:17 -0500 Message-Id: <20210211162427.618913-5-pasha.tatashin@soleen.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210211162427.618913-1-pasha.tatashin@soleen.com> References: <20210211162427.618913-1-pasha.tatashin@soleen.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org It is still possible that we pin movable CMA pages if there are isolation errors and cma_page_list stays empty when we check again. Check for isolation errors, and return success only when there are no isolation errors, and cma_page_list is empty after checking. Because isolation errors are transient, we retry indefinitely. Fixes: 9a4e9f3b2d73 ("mm: update get_user_pages_longterm to migrate pages allocated from CMA region") Signed-off-by: Pavel Tatashin Reviewed-by: Jason Gunthorpe --- mm/gup.c | 60 ++++++++++++++++++++++++++++++++------------------------ 1 file changed, 34 insertions(+), 26 deletions(-) diff --git a/mm/gup.c b/mm/gup.c index eb8c39953d53..b1f6d56182b3 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -1547,8 +1547,8 @@ static long check_and_migrate_cma_pages(struct mm_struct *mm, struct vm_area_struct **vmas, unsigned int gup_flags) { - unsigned long i; - bool drain_allow = true; + unsigned long i, isolation_error_count; + bool drain_allow; LIST_HEAD(cma_page_list); long ret = nr_pages; struct page *prev_head, *head; @@ -1559,6 +1559,8 @@ static long check_and_migrate_cma_pages(struct mm_struct *mm, check_again: prev_head = NULL; + isolation_error_count = 0; + drain_allow = true; for (i = 0; i < nr_pages; i++) { head = compound_head(pages[i]); if (head == prev_head) @@ -1570,25 +1572,35 @@ static long check_and_migrate_cma_pages(struct mm_struct *mm, * of the CMA zone if possible. */ if (is_migrate_cma_page(head)) { - if (PageHuge(head)) - isolate_huge_page(head, &cma_page_list); - else { + if (PageHuge(head)) { + if (!isolate_huge_page(head, &cma_page_list)) + isolation_error_count++; + } else { if (!PageLRU(head) && drain_allow) { lru_add_drain_all(); drain_allow = false; } - if (!isolate_lru_page(head)) { - list_add_tail(&head->lru, &cma_page_list); - mod_node_page_state(page_pgdat(head), - NR_ISOLATED_ANON + - page_is_file_lru(head), - thp_nr_pages(head)); + if (isolate_lru_page(head)) { + isolation_error_count++; + continue; } + list_add_tail(&head->lru, &cma_page_list); + mod_node_page_state(page_pgdat(head), + NR_ISOLATED_ANON + + page_is_file_lru(head), + thp_nr_pages(head)); } } } + /* + * If list is empty, and no isolation errors, means that all pages are + * in the correct zone. + */ + if (list_empty(&cma_page_list) && !isolation_error_count) + return ret; + if (!list_empty(&cma_page_list)) { /* * drop the above get_user_pages reference. @@ -1608,23 +1620,19 @@ static long check_and_migrate_cma_pages(struct mm_struct *mm, return ret > 0 ? -ENOMEM : ret; } - /* - * We did migrate all the pages, Try to get the page references - * again migrating any new CMA pages which we failed to isolate - * earlier. - */ - ret = __get_user_pages_locked(mm, start, nr_pages, - pages, vmas, NULL, - gup_flags); - - if (ret > 0) { - nr_pages = ret; - drain_allow = true; - goto check_again; - } + /* We unpinned pages before migration, pin them again */ + ret = __get_user_pages_locked(mm, start, nr_pages, pages, vmas, + NULL, gup_flags); + if (ret <= 0) + return ret; + nr_pages = ret; } - return ret; + /* + * check again because pages were unpinned, and we also might have + * had isolation errors and need more pages to migrate. + */ + goto check_again; } #else static long check_and_migrate_cma_pages(struct mm_struct *mm, From patchwork Thu Feb 11 16:24:18 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pasha Tatashin X-Patchwork-Id: 12083705 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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 20DF2C433DB for ; Thu, 11 Feb 2021 16:28:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D886864EAC for ; Thu, 11 Feb 2021 16:28:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229999AbhBKQ2J (ORCPT ); Thu, 11 Feb 2021 11:28:09 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36688 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232048AbhBKQZp (ORCPT ); Thu, 11 Feb 2021 11:25:45 -0500 Received: from mail-qv1-xf2e.google.com (mail-qv1-xf2e.google.com [IPv6:2607:f8b0:4864:20::f2e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 31231C06121D for ; Thu, 11 Feb 2021 08:24:38 -0800 (PST) Received: by mail-qv1-xf2e.google.com with SMTP id dr7so1031014qvb.1 for ; Thu, 11 Feb 2021 08:24:38 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=soleen.com; s=google; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=Ufntx25tuWpjxsF06Bkywh8J0szWGmEjnxPrz0f+TBc=; b=TvNCbT66pFSe3p8Xkp76H8muh5jL/l2PbIgtvVK1gHwcltperHmaEqgwn6oQhHUaIk U67Ath/wNcOYztGbVhWraX+NWPiLCW3D8+DR9fevz8UHFVVQauuelyjuJDm9oqRhz89M LPwi5DXGzxciP6YCVzo2+bwM5OtovbF/7e8otVoXzmOdy7VoSYQlCsm+RvOwR7iIUV6F odIoqynwSW702ZYrda1g3szn/ztBT/FGFzag6NhXJPnFiii29kG3GX1kpJ0RomhzWqmb Cci+0C4EZ8tzIkxxcZ13iqYvUEdKrI95d/qN6kF85TmExaQ+RhC4HW9n08MLir09/7VA bryQ== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=Ufntx25tuWpjxsF06Bkywh8J0szWGmEjnxPrz0f+TBc=; b=HYInMGd4bPdaVCYIHlXcTLn0ptlc0IrsS4hCQYnhWdLJ1fPBbACnCK7Vse7i5CoCzB GvI0XWAV+7a3HJZgoHE9pnBLlNe5PmtbIL2QdlBhufUPywZSXW6G7zeaVCsQkdkDNGWv IuFN9NpqKPTPd2NxgH4I6pfe/ilUp+Kbj1K40jZnqf80uaBFLikru0DOWDL8mbQCk3bE DhOw6lfiYCqehpCKNazg2w1dT+Dti2DgJ4Y+XG/s0u9ggAKcbtatxQFnKF1rvL8GZztd pc4Ba2NWrKVxfnBrNa+KnfD0706xtAKdKMDEGR3TYJgK3/IOxBaUp7XWTTKuNhL6+32W G7MA== X-Gm-Message-State: AOAM530oami4B7iOqL2YdVwNm2MLicsgnwKzUDdrJkjdz9Axr1rqfijn DqYBZRY+lUD4SKT2y7p/5AcSVw== X-Google-Smtp-Source: ABdhPJwJJeVBsCfzNY+B9NzcUIyqoVOG4NYWe1VSfprHJtmGisgKtUjVY3jmgNij3Hu+A9h3Ru4+vA== X-Received: by 2002:a0c:b998:: with SMTP id v24mr8318876qvf.4.1613060677409; Thu, 11 Feb 2021 08:24:37 -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 i23sm3831778qtq.42.2021.02.11.08.24.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 11 Feb 2021 08:24:36 -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 v10 05/14] mm cma: rename PF_MEMALLOC_NOCMA to PF_MEMALLOC_PIN Date: Thu, 11 Feb 2021 11:24:18 -0500 Message-Id: <20210211162427.618913-6-pasha.tatashin@soleen.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210211162427.618913-1-pasha.tatashin@soleen.com> References: <20210211162427.618913-1-pasha.tatashin@soleen.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org PF_MEMALLOC_NOCMA is used ot guarantee that the allocator will not return pages that might belong to CMA region. This is currently used for long term gup to make sure that such pins are not going to be done on any CMA pages. When PF_MEMALLOC_NOCMA has been introduced we haven't realized that it is focusing on CMA pages too much and that there is larger class of pages that need the same treatment. MOVABLE zone cannot contain any long term pins as well so it makes sense to reuse and redefine this flag for that usecase as well. Rename the flag to PF_MEMALLOC_PIN which defines an allocation context which can only get pages suitable for long-term pins. Also re-name: memalloc_nocma_save()/memalloc_nocma_restore to memalloc_pin_save()/memalloc_pin_restore() and make the new functions common. Signed-off-by: Pavel Tatashin Reviewed-by: John Hubbard Acked-by: Michal Hocko --- include/linux/sched.h | 2 +- include/linux/sched/mm.h | 21 +++++---------------- mm/gup.c | 4 ++-- mm/hugetlb.c | 4 ++-- mm/page_alloc.c | 4 ++-- 5 files changed, 12 insertions(+), 23 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index 96837243931a..62c639d67fe3 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1576,7 +1576,7 @@ extern struct pid *cad_pid; #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */ #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ -#define PF_MEMALLOC_NOCMA 0x10000000 /* All allocation request will have _GFP_MOVABLE cleared */ +#define PF_MEMALLOC_PIN 0x10000000 /* Allocation context constrained to zones which allow long term pinning. */ #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */ #define PF_SUSPEND_TASK 0x80000000 /* This thread called freeze_processes() and should not be frozen */ diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h index 1ae08b8462a4..5f4dd3274734 100644 --- a/include/linux/sched/mm.h +++ b/include/linux/sched/mm.h @@ -270,29 +270,18 @@ static inline void memalloc_noreclaim_restore(unsigned int flags) current->flags = (current->flags & ~PF_MEMALLOC) | flags; } -#ifdef CONFIG_CMA -static inline unsigned int memalloc_nocma_save(void) +static inline unsigned int memalloc_pin_save(void) { - unsigned int flags = current->flags & PF_MEMALLOC_NOCMA; + unsigned int flags = current->flags & PF_MEMALLOC_PIN; - current->flags |= PF_MEMALLOC_NOCMA; + current->flags |= PF_MEMALLOC_PIN; return flags; } -static inline void memalloc_nocma_restore(unsigned int flags) +static inline void memalloc_pin_restore(unsigned int flags) { - current->flags = (current->flags & ~PF_MEMALLOC_NOCMA) | flags; + current->flags = (current->flags & ~PF_MEMALLOC_PIN) | flags; } -#else -static inline unsigned int memalloc_nocma_save(void) -{ - return 0; -} - -static inline void memalloc_nocma_restore(unsigned int flags) -{ -} -#endif #ifdef CONFIG_MEMCG DECLARE_PER_CPU(struct mem_cgroup *, int_active_memcg); diff --git a/mm/gup.c b/mm/gup.c index b1f6d56182b3..489bc02fc008 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -1661,7 +1661,7 @@ static long __gup_longterm_locked(struct mm_struct *mm, long rc; if (gup_flags & FOLL_LONGTERM) - flags = memalloc_nocma_save(); + flags = memalloc_pin_save(); rc = __get_user_pages_locked(mm, start, nr_pages, pages, vmas, NULL, gup_flags); @@ -1670,7 +1670,7 @@ static long __gup_longterm_locked(struct mm_struct *mm, if (rc > 0) rc = check_and_migrate_cma_pages(mm, start, rc, pages, vmas, gup_flags); - memalloc_nocma_restore(flags); + memalloc_pin_restore(flags); } return rc; } diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 0b7079dd0d35..1d909879c1b4 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1044,10 +1044,10 @@ static void enqueue_huge_page(struct hstate *h, struct page *page) static struct page *dequeue_huge_page_node_exact(struct hstate *h, int nid) { struct page *page; - bool nocma = !!(current->flags & PF_MEMALLOC_NOCMA); + bool pin = !!(current->flags & PF_MEMALLOC_PIN); list_for_each_entry(page, &h->hugepage_freelists[nid], lru) { - if (nocma && is_migrate_cma_page(page)) + if (pin && is_migrate_cma_page(page)) continue; if (PageHWPoison(page)) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 0b55c9c95364..c843dd64a74a 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3814,8 +3814,8 @@ static inline unsigned int current_alloc_flags(gfp_t gfp_mask, #ifdef CONFIG_CMA unsigned int pflags = current->flags; - if (!(pflags & PF_MEMALLOC_NOCMA) && - gfp_migratetype(gfp_mask) == MIGRATE_MOVABLE) + if (!(pflags & PF_MEMALLOC_PIN) && + gfp_migratetype(gfp_mask) == MIGRATE_MOVABLE) alloc_flags |= ALLOC_CMA; #endif From patchwork Thu Feb 11 16:24:19 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pasha Tatashin X-Patchwork-Id: 12083717 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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 8801BC43331 for ; Thu, 11 Feb 2021 16:30:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6100C64E95 for ; 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[73.69.118.222]) by smtp.gmail.com with ESMTPSA id i23sm3831778qtq.42.2021.02.11.08.24.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 11 Feb 2021 08:24:38 -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 v10 06/14] mm: apply per-task gfp constraints in fast path Date: Thu, 11 Feb 2021 11:24:19 -0500 Message-Id: <20210211162427.618913-7-pasha.tatashin@soleen.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210211162427.618913-1-pasha.tatashin@soleen.com> References: <20210211162427.618913-1-pasha.tatashin@soleen.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Function current_gfp_context() is called after fast path. However, soon we will add more constraints which will also limit zones based on context. Move this call into fast path, and apply the correct constraints for all allocations. Also update .reclaim_idx based on value returned by current_gfp_context() because it soon will modify the allowed zones. Note: With this patch we will do one extra current->flags load during fast path, but we already load current->flags in fast-path: __alloc_pages_nodemask() prepare_alloc_pages() current_alloc_flags(gfp_mask, *alloc_flags); Later, when we add the zone constrain logic to current_gfp_context() we will be able to remove current->flags load from current_alloc_flags, and therefore return fast-path to the current performance level. Suggested-by: Michal Hocko Signed-off-by: Pavel Tatashin Acked-by: Michal Hocko --- mm/page_alloc.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index c843dd64a74a..92f1741285c1 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -4982,6 +4982,13 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, int preferred_nid, } gfp_mask &= gfp_allowed_mask; + /* + * Apply scoped allocation constraints. This is mainly about GFP_NOFS + * resp. GFP_NOIO which has to be inherited for all allocation requests + * from a particular context which has been marked by + * memalloc_no{fs,io}_{save,restore}. + */ + gfp_mask = current_gfp_context(gfp_mask); alloc_mask = gfp_mask; if (!prepare_alloc_pages(gfp_mask, order, preferred_nid, nodemask, &ac, &alloc_mask, &alloc_flags)) return NULL; @@ -4997,13 +5004,7 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, int preferred_nid, if (likely(page)) goto out; - /* - * Apply scoped allocation constraints. This is mainly about GFP_NOFS - * resp. GFP_NOIO which has to be inherited for all allocation requests - * from a particular context which has been marked by - * memalloc_no{fs,io}_{save,restore}. - */ - alloc_mask = current_gfp_context(gfp_mask); + alloc_mask = gfp_mask; ac.spread_dirty_pages = false; /* From patchwork Thu Feb 11 16:24:20 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pasha Tatashin X-Patchwork-Id: 12083715 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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 0DD4DC4332B for ; Thu, 11 Feb 2021 16:30:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DE5B964EAC for ; Thu, 11 Feb 2021 16:30:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231913AbhBKQaL (ORCPT ); Thu, 11 Feb 2021 11:30:11 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36564 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231879AbhBKQ1e (ORCPT ); Thu, 11 Feb 2021 11:27:34 -0500 Received: from mail-qk1-x732.google.com (mail-qk1-x732.google.com [IPv6:2607:f8b0:4864:20::732]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5378CC061224 for ; Thu, 11 Feb 2021 08:24:41 -0800 (PST) Received: by mail-qk1-x732.google.com with SMTP id f17so2423522qkl.5 for ; Thu, 11 Feb 2021 08:24:41 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=soleen.com; s=google; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=Fx+uyJzjSbr3xf7P5cKDWVSLakeN8Tvy+jsB75DziiM=; b=UwdEAEwlxVfw+ZL+GJXdkv2+cnuUCp83RFgqUXFisUsTaIwQglT/KBClE/HnEFXwBZ 6tgJc77k7di2TMRgjOgVTkhDP6XQGWhBz09T8HsHAbPI3ovHUzv+GSZMOd+Q51f0JTf0 RF74SKKWlHUl13C69NpkSzSDZ5pZiO8NKdgwSmiLK9LFcf14blaeBKppvDAD3yMBrGve OEn+/XAIlthvHgjvMHqXYt0qwGQ67NWCdh7CFhK+gOLwtf7zxliXkxAcqsyjKp2RChWu 35bUxM4w5upA4QgZBGVZ6VcyLJX0EFHGE0eYZ6BewNB+MJfgBEWW8Bau/s0EYi09UqlE R4JQ== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=Fx+uyJzjSbr3xf7P5cKDWVSLakeN8Tvy+jsB75DziiM=; b=GAT2T4jI5vucNEnyYXaXgmUnX1DZBQsxdb/6bE32Qs3vp/+K7whTNpQebG/iC2jXBE bP2O/0CwG3fUVUp12U5nEIiP6rCDoYMasTRcz9grv1FqRpKFBcDKpDEhHe6dpz0GItJc Yqi8D/NYte+wiczr9fcUlL3eWL+CuKPj/xoXMbmZRrt/VYSwMCg2fB0B73EkA8lqiSNh UAjrhC9VlRzdlUzkCC2ZFeBlgabkKLvwRq8hzBY+uu9+GA+4n3Dn3pG3Ln3sIdYoHIXj 7Y4omgH39+BJKoKGoe3VVEjWo/gKzCcLQ8dDioPhJNQvPvAsfpd43dHXY5RwTIxGD8u7 hVAw== X-Gm-Message-State: AOAM530ZW/EVX8K2ggd9fQ4Fu1ua2+4lNKcj6kMM2Jg78Dim9KAroTFs aGoepFMfdUtmbNs3GcGh83hPrA== X-Google-Smtp-Source: ABdhPJye0lr62d3KgzMZo9HLK2YfHazRHGH2E/6cr2XB8yOzoeyGwo/BE/gJlRKD01WrgHRI3/6XWg== X-Received: by 2002:a05:620a:79a:: with SMTP id 26mr9041957qka.302.1613060680526; Thu, 11 Feb 2021 08:24:40 -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 i23sm3831778qtq.42.2021.02.11.08.24.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 11 Feb 2021 08:24:40 -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 v10 07/14] mm: honor PF_MEMALLOC_PIN for all movable pages Date: Thu, 11 Feb 2021 11:24:20 -0500 Message-Id: <20210211162427.618913-8-pasha.tatashin@soleen.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210211162427.618913-1-pasha.tatashin@soleen.com> References: <20210211162427.618913-1-pasha.tatashin@soleen.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org PF_MEMALLOC_PIN is only honored for CMA pages, extend this flag to work for any allocations from ZONE_MOVABLE by removing __GFP_MOVABLE from gfp_mask when this flag is passed in the current context. Add is_pinnable_page() to return true if page is in a pinnable page. A pinnable page is not in ZONE_MOVABLE and not of MIGRATE_CMA type. Signed-off-by: Pavel Tatashin Acked-by: Michal Hocko --- include/linux/mm.h | 18 ++++++++++++++++++ include/linux/sched/mm.h | 6 +++++- mm/hugetlb.c | 2 +- mm/page_alloc.c | 20 +++++++++----------- 4 files changed, 33 insertions(+), 13 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 89fca443e6f1..9a31b2298c1d 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1122,6 +1122,24 @@ static inline bool is_zone_device_page(const struct page *page) } #endif +static inline bool is_zone_movable_page(const struct page *page) +{ + return page_zonenum(page) == ZONE_MOVABLE; +} + +/* MIGRATE_CMA and ZONE_MOVABLE do not allow pin pages */ +#ifdef CONFIG_MIGRATION +static inline bool is_pinnable_page(struct page *page) +{ + return !is_zone_movable_page(page) && !is_migrate_cma_page(page); +} +#else +static inline bool is_pinnable_page(struct page *page) +{ + return true; +} +#endif + #ifdef CONFIG_DEV_PAGEMAP_OPS void free_devmap_managed_page(struct page *page); DECLARE_STATIC_KEY_FALSE(devmap_managed_key); diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h index 5f4dd3274734..a55277b0d475 100644 --- a/include/linux/sched/mm.h +++ b/include/linux/sched/mm.h @@ -150,12 +150,13 @@ static inline bool in_vfork(struct task_struct *tsk) * Applies per-task gfp context to the given allocation flags. * PF_MEMALLOC_NOIO implies GFP_NOIO * PF_MEMALLOC_NOFS implies GFP_NOFS + * PF_MEMALLOC_PIN implies !GFP_MOVABLE */ static inline gfp_t current_gfp_context(gfp_t flags) { unsigned int pflags = READ_ONCE(current->flags); - if (unlikely(pflags & (PF_MEMALLOC_NOIO | PF_MEMALLOC_NOFS))) { + if (unlikely(pflags & (PF_MEMALLOC_NOIO | PF_MEMALLOC_NOFS | PF_MEMALLOC_PIN))) { /* * NOIO implies both NOIO and NOFS and it is a weaker context * so always make sure it makes precedence @@ -164,6 +165,9 @@ static inline gfp_t current_gfp_context(gfp_t flags) flags &= ~(__GFP_IO | __GFP_FS); else if (pflags & PF_MEMALLOC_NOFS) flags &= ~__GFP_FS; + + if (pflags & PF_MEMALLOC_PIN) + flags &= ~__GFP_MOVABLE; } return flags; } diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 1d909879c1b4..90c4d279dec4 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1047,7 +1047,7 @@ static struct page *dequeue_huge_page_node_exact(struct hstate *h, int nid) bool pin = !!(current->flags & PF_MEMALLOC_PIN); list_for_each_entry(page, &h->hugepage_freelists[nid], lru) { - if (pin && is_migrate_cma_page(page)) + if (pin && !is_pinnable_page(page)) continue; if (PageHWPoison(page)) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 92f1741285c1..d21d3c12aa31 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3808,16 +3808,13 @@ alloc_flags_nofragment(struct zone *zone, gfp_t gfp_mask) return alloc_flags; } -static inline unsigned int current_alloc_flags(gfp_t gfp_mask, - unsigned int alloc_flags) +/* Must be called after current_gfp_context() which can change gfp_mask */ +static inline unsigned int gfp_to_alloc_flags_cma(gfp_t gfp_mask, + unsigned int alloc_flags) { #ifdef CONFIG_CMA - unsigned int pflags = current->flags; - - if (!(pflags & PF_MEMALLOC_PIN) && - gfp_migratetype(gfp_mask) == MIGRATE_MOVABLE) + if (gfp_migratetype(gfp_mask) == MIGRATE_MOVABLE) alloc_flags |= ALLOC_CMA; - #endif return alloc_flags; } @@ -4473,7 +4470,7 @@ gfp_to_alloc_flags(gfp_t gfp_mask) } else if (unlikely(rt_task(current)) && !in_interrupt()) alloc_flags |= ALLOC_HARDER; - alloc_flags = current_alloc_flags(gfp_mask, alloc_flags); + alloc_flags = gfp_to_alloc_flags_cma(gfp_mask, alloc_flags); return alloc_flags; } @@ -4775,7 +4772,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, reserve_flags = __gfp_pfmemalloc_flags(gfp_mask); if (reserve_flags) - alloc_flags = current_alloc_flags(gfp_mask, reserve_flags); + alloc_flags = gfp_to_alloc_flags_cma(gfp_mask, reserve_flags); /* * Reset the nodemask and zonelist iterators if memory policies can be @@ -4944,7 +4941,7 @@ static inline bool prepare_alloc_pages(gfp_t gfp_mask, unsigned int order, if (should_fail_alloc_page(gfp_mask, order)) return false; - *alloc_flags = current_alloc_flags(gfp_mask, *alloc_flags); + *alloc_flags = gfp_to_alloc_flags_cma(gfp_mask, *alloc_flags); /* Dirty zone balancing only done in the fast path */ ac->spread_dirty_pages = (gfp_mask & __GFP_WRITE); @@ -4986,7 +4983,8 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, int preferred_nid, * Apply scoped allocation constraints. This is mainly about GFP_NOFS * resp. GFP_NOIO which has to be inherited for all allocation requests * from a particular context which has been marked by - * memalloc_no{fs,io}_{save,restore}. + * memalloc_no{fs,io}_{save,restore}. And PF_MEMALLOC_PIN which ensures + * movable zones are not used during allocation. */ gfp_mask = current_gfp_context(gfp_mask); alloc_mask = gfp_mask; From patchwork Thu Feb 11 16:24:21 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pasha Tatashin X-Patchwork-Id: 12083713 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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 1FCECC4332D for ; Thu, 11 Feb 2021 16:30:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F1B05601FD for ; Thu, 11 Feb 2021 16:30:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231838AbhBKQaK (ORCPT ); Thu, 11 Feb 2021 11:30:10 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36576 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231913AbhBKQ1e (ORCPT ); Thu, 11 Feb 2021 11:27:34 -0500 Received: from mail-qv1-xf2a.google.com (mail-qv1-xf2a.google.com [IPv6:2607:f8b0:4864:20::f2a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C1DD2C0611C1 for ; Thu, 11 Feb 2021 08:24:42 -0800 (PST) Received: by mail-qv1-xf2a.google.com with SMTP id ew18so2814764qvb.4 for ; Thu, 11 Feb 2021 08:24:42 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=soleen.com; s=google; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=vFtb7b0TLXam2e0aSgOj3DDhIq1OSPT7SAwjt/JgMSo=; b=GuSLnZfP8wJEXP3BvQ+7AnENrHoKxCqomT/DlUEKn8z/43ED1ocN+7Rjb5Xy9YLI7D PMvihL04KPGberT/PXD29PCzYnmUf7r2qu0nc4+uowMSJ9tRymgKYkn4hJqQO1LjJHij lcIjjVMuc1ZyVKAHY2hfAcvmVkzLB0S1h9/6IMFOB1vegIEKnqRuwjIE3fQzUnFQgys9 xIYUEH37orhL0JpDvprzfPSs6GL9vUyWtVc0Sy7x7+6uFB88Bgr+W+xwf3Usp2TwVZ8l FwOGshdMCz44xib67tlBOu0DEu0P3Nwd8uyzATPsdk4ZQtVN1B618BcB+SKvt4r6rqdQ 5qvg== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=vFtb7b0TLXam2e0aSgOj3DDhIq1OSPT7SAwjt/JgMSo=; b=T/xg8omQAXQuTQI6E4p394RS39GrtIceP4J2Go/GmgFB2HO2mZuzRg3WjtKdeOhLXK 96ExfuNqqhkltq4a24XORW/8+bsenul4KI1BOjeDtAlMEJrtLyCLR9pr5xD4RjeSdkf9 yWSYX/rwEAibaPsJ9Po8keSuiR+oIBbqhUydCLZqvrRXdb5ZEI5hvjAVKsmM+ZjDB4CK 5R4ggOViz8hhkFhU6HQb+wHzB5dPM6rP9AGlHyD8XEWeGlpdbyW+hIKld400y+9J67mS ryloI28EBvooYZ52XU2GZxBlYU4XdbAcZEJv9YiYdPY/9C1b6L1Tbo70qudX4j2EYjNg nzwA== X-Gm-Message-State: AOAM533U6fniDmfEKpfX8fmN6Jbv0WuJmsdJYgO4KY+17GjFhOLrcNox kPuFTDYQaq9JjVDKIV58a4H14Q== X-Google-Smtp-Source: ABdhPJyDv3BizAlWiHVEhqxZDYR768wuEmVRtyBG373FDXh51pcNa96wloLfU8fidQTqpajQEDtbIQ== X-Received: by 2002:a0c:b66c:: with SMTP id q44mr8438487qvf.3.1613060682040; Thu, 11 Feb 2021 08:24:42 -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 i23sm3831778qtq.42.2021.02.11.08.24.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 11 Feb 2021 08:24:41 -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 v10 08/14] mm/gup: do not migrate zero page Date: Thu, 11 Feb 2021 11:24:21 -0500 Message-Id: <20210211162427.618913-9-pasha.tatashin@soleen.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210211162427.618913-1-pasha.tatashin@soleen.com> References: <20210211162427.618913-1-pasha.tatashin@soleen.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org On some platforms ZERO_PAGE(0) might end-up in a movable zone. Do not migrate zero page in gup during longterm pinning as migration of zero page is not allowed. For example, in x86 QEMU with 16G of memory and kernelcore=5G parameter, I see the following: Boot#1: zero_pfn 0x48a8d zero_pfn zone: ZONE_DMA32 Boot#2: zero_pfn 0x20168d zero_pfn zone: ZONE_MOVABLE On x86, empty_zero_page is declared in .bss and depending on the loader may end up in different physical locations during boots. Also, move is_zero_pfn() my_zero_pfn() functions under CONFIG_MMU, because zero_pfn that they are using is declared in memory.c which is compiled with CONFIG_MMU. Signed-off-by: Pavel Tatashin --- include/linux/mm.h | 3 ++- include/linux/mmzone.h | 4 ++++ include/linux/pgtable.h | 12 ++++++++++++ 3 files changed, 18 insertions(+), 1 deletion(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 9a31b2298c1d..9ea4b9305ae5 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1131,7 +1131,8 @@ static inline bool is_zone_movable_page(const struct page *page) #ifdef CONFIG_MIGRATION static inline bool is_pinnable_page(struct page *page) { - return !is_zone_movable_page(page) && !is_migrate_cma_page(page); + return !(is_zone_movable_page(page) || is_migrate_cma_page(page)) || + is_zero_pfn(page_to_pfn(page)); } #else static inline bool is_pinnable_page(struct page *page) diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 47946cec7584..66132f8f051e 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -427,6 +427,10 @@ enum zone_type { * techniques might use alloc_contig_range() to hide previously * exposed pages from the buddy again (e.g., to implement some sort * of memory unplug in virtio-mem). + * 6. ZERO_PAGE(0), kernelcore/movablecore setups might create + * situations where ZERO_PAGE(0) which is allocated differently + * on different platforms may end up in a movable zone. ZERO_PAGE(0) + * cannot be migrated. * * In general, no unmovable allocations that degrade memory offlining * should end up in ZONE_MOVABLE. Allocators (like alloc_contig_range()) diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h index cdfc4e9f253e..9a218d7eed06 100644 --- a/include/linux/pgtable.h +++ b/include/linux/pgtable.h @@ -1107,6 +1107,7 @@ extern void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn, extern void untrack_pfn_moved(struct vm_area_struct *vma); #endif +#ifdef CONFIG_MMU #ifdef __HAVE_COLOR_ZERO_PAGE static inline int is_zero_pfn(unsigned long pfn) { @@ -1130,6 +1131,17 @@ static inline unsigned long my_zero_pfn(unsigned long addr) return zero_pfn; } #endif +#else +static inline int is_zero_pfn(unsigned long pfn) +{ + return 0; +} + +static inline unsigned long my_zero_pfn(unsigned long addr) +{ + return 0; +} +#endif /* CONFIG_MMU */ #ifdef CONFIG_MMU From patchwork Thu Feb 11 16:24:22 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pasha Tatashin X-Patchwork-Id: 12083707 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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 797BBC433E6 for ; Thu, 11 Feb 2021 16:30:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4F4FC64EAC for ; Thu, 11 Feb 2021 16:30:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230402AbhBKQaA (ORCPT ); Thu, 11 Feb 2021 11:30:00 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36586 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231932AbhBKQ1k (ORCPT ); Thu, 11 Feb 2021 11:27:40 -0500 Received: from mail-qk1-x735.google.com (mail-qk1-x735.google.com [IPv6:2607:f8b0:4864:20::735]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6A3EEC0611C3 for ; Thu, 11 Feb 2021 08:24:44 -0800 (PST) Received: by mail-qk1-x735.google.com with SMTP id f17so2423727qkl.5 for ; Thu, 11 Feb 2021 08:24:44 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=soleen.com; s=google; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=prBG2yVd2SajcEA/vsXnJLf3ft/ILJg+F6BSYByezwk=; b=oAz0Ya81ae7I30nLXl3tvldk+DxVr8ux7PhzfLxLavCJTOtezoamvvZbpwIIO/GI3B K5WdoPaOpjpPx5goaDk/Dqc5b0WPYO0CbTKQQfEQwCTr2qQB/jJO+RMuDGKqL/1373Fg ddsw/WOGiVYr/NpsvFPiTOiwTV/+UsT3r1nhNsMqDDAPKeeVxzC0JI8ltxeMOs55FVpM 8h4IGwf1fRdWpHtQh33qnixErY+KayDRDICpZe0rxNudn3lDX/ftewm9BYcUOvtyosjV /SRBC6kOqx4Af170XZtLCgXinNxuYAgbB8aFnBQg1nBdrdfAlvEe/dP6e3ExxKDp2NIm fVqQ== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=prBG2yVd2SajcEA/vsXnJLf3ft/ILJg+F6BSYByezwk=; b=ow+qon+1KUukUbKeqI85soY+DnjWG7GGK5v7zhX/6yWSl1JYeA1fXZPXzENYUObzC1 O4MYFw79S9mvNwTBrMabVX/C0wm3Xh4LqNnWLQNKKI4as6BFOHQG9dHDqCGlYPsN9eFx VoYnrn5yz0hR/RolA9SPYd/YyiloU/08H9IyOfoTIEogm/FQe8dhTvLwG0Z5509y7C8y oxakSQk+zLjOZsM6QbJ0f5TesjVf2pd+ieIjoG+iw4q9FFg93Elwuixia3aXsJEBLUgL xoG2F7pDwPt7z9hVXeP1f33nOxAdOz8O4+ne2DhQ8oxm+1+HPtj6g4FbhS/Mr93xQECU BhSg== X-Gm-Message-State: AOAM530p7SOSL7BDXWSzmh56RWdTvYa+M5hwsJsEGZYOuywE2EaYtP/u xhTErfVWqKyP9g6NA2zbQGImOw== X-Google-Smtp-Source: ABdhPJwGybK/jkhl+f1vZV40TFv7W218JXCOOLntEKFx1GZ4Vc1iNyzASNNjFKKIWhOo6BKAqOE+Qg== X-Received: by 2002:a37:7b02:: with SMTP id w2mr9028732qkc.291.1613060683612; Thu, 11 Feb 2021 08:24:43 -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 i23sm3831778qtq.42.2021.02.11.08.24.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 11 Feb 2021 08:24:43 -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 v10 09/14] mm/gup: migrate pinned pages out of movable zone Date: Thu, 11 Feb 2021 11:24:22 -0500 Message-Id: <20210211162427.618913-10-pasha.tatashin@soleen.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210211162427.618913-1-pasha.tatashin@soleen.com> References: <20210211162427.618913-1-pasha.tatashin@soleen.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org We should not pin pages in ZONE_MOVABLE. Currently, we do not pin only movable CMA pages. Generalize the function that migrates CMA pages to migrate all movable pages. Use is_pinnable_page() to check which pages need to be migrated Signed-off-by: Pavel Tatashin Reviewed-by: John Hubbard --- include/linux/migrate.h | 1 + include/linux/mmzone.h | 9 ++++- include/trace/events/migrate.h | 3 +- mm/gup.c | 67 +++++++++++++++++----------------- 4 files changed, 44 insertions(+), 36 deletions(-) diff --git a/include/linux/migrate.h b/include/linux/migrate.h index 3a389633b68f..fdf65f23acec 100644 --- a/include/linux/migrate.h +++ b/include/linux/migrate.h @@ -27,6 +27,7 @@ enum migrate_reason { MR_MEMPOLICY_MBIND, MR_NUMA_MISPLACED, MR_CONTIG_RANGE, + MR_LONGTERM_PIN, MR_TYPES }; diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 66132f8f051e..5e0f79a4092b 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -407,8 +407,13 @@ enum zone_type { * to increase the number of THP/huge pages. Notable special cases are: * * 1. Pinned pages: (long-term) pinning of movable pages might - * essentially turn such pages unmovable. Memory offlining might - * retry a long time. + * essentially turn such pages unmovable. Therefore, we do not allow + * pinning long-term pages in ZONE_MOVABLE. When pages are pinned and + * faulted, they come from the right zone right away. However, it is + * still possible that address space already has pages in + * ZONE_MOVABLE at the time when pages are pinned (i.e. user has + * touches that memory before pinning). In such case we migrate them + * to a different zone. When migration fails - pinning fails. * 2. memblock allocations: kernelcore/movablecore setups might create * situations where ZONE_MOVABLE contains unmovable allocations * after boot. Memory offlining and allocations fail early. diff --git a/include/trace/events/migrate.h b/include/trace/events/migrate.h index 4d434398d64d..363b54ce104c 100644 --- a/include/trace/events/migrate.h +++ b/include/trace/events/migrate.h @@ -20,7 +20,8 @@ EM( MR_SYSCALL, "syscall_or_cpuset") \ EM( MR_MEMPOLICY_MBIND, "mempolicy_mbind") \ EM( MR_NUMA_MISPLACED, "numa_misplaced") \ - EMe(MR_CONTIG_RANGE, "contig_range") + EM( MR_CONTIG_RANGE, "contig_range") \ + EMe(MR_LONGTERM_PIN, "longterm_pin") /* * First define the enums in the above macros to be exported to userspace diff --git a/mm/gup.c b/mm/gup.c index 489bc02fc008..ced2303dc59e 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -87,11 +87,12 @@ __maybe_unused struct page *try_grab_compound_head(struct page *page, int orig_refs = refs; /* - * Can't do FOLL_LONGTERM + FOLL_PIN with CMA in the gup fast - * path, so fail and let the caller fall back to the slow path. + * Can't do FOLL_LONGTERM + FOLL_PIN gup fast path if not in a + * right zone, so fail and let the caller fall back to the slow + * path. */ - if (unlikely(flags & FOLL_LONGTERM) && - is_migrate_cma_page(page)) + if (unlikely((flags & FOLL_LONGTERM) && + !is_pinnable_page(page))) return NULL; /* @@ -1539,17 +1540,17 @@ struct page *get_dump_page(unsigned long addr) } #endif /* CONFIG_ELF_CORE */ -#ifdef CONFIG_CMA -static long check_and_migrate_cma_pages(struct mm_struct *mm, - unsigned long start, - unsigned long nr_pages, - struct page **pages, - struct vm_area_struct **vmas, - unsigned int gup_flags) +#ifdef CONFIG_MIGRATION +static long check_and_migrate_movable_pages(struct mm_struct *mm, + unsigned long start, + unsigned long nr_pages, + struct page **pages, + struct vm_area_struct **vmas, + unsigned int gup_flags) { unsigned long i, isolation_error_count; bool drain_allow; - LIST_HEAD(cma_page_list); + LIST_HEAD(movable_page_list); long ret = nr_pages; struct page *prev_head, *head; struct migration_target_control mtc = { @@ -1567,13 +1568,12 @@ static long check_and_migrate_cma_pages(struct mm_struct *mm, continue; prev_head = head; /* - * If we get a page from the CMA zone, since we are going to - * be pinning these entries, we might as well move them out - * of the CMA zone if possible. + * If we get a movable page, since we are going to be pinning + * these entries, try to move them out if possible. */ - if (is_migrate_cma_page(head)) { + if (!is_pinnable_page(head)) { if (PageHuge(head)) { - if (!isolate_huge_page(head, &cma_page_list)) + if (!isolate_huge_page(head, &movable_page_list)) isolation_error_count++; } else { if (!PageLRU(head) && drain_allow) { @@ -1585,7 +1585,7 @@ static long check_and_migrate_cma_pages(struct mm_struct *mm, isolation_error_count++; continue; } - list_add_tail(&head->lru, &cma_page_list); + list_add_tail(&head->lru, &movable_page_list); mod_node_page_state(page_pgdat(head), NR_ISOLATED_ANON + page_is_file_lru(head), @@ -1598,10 +1598,10 @@ static long check_and_migrate_cma_pages(struct mm_struct *mm, * If list is empty, and no isolation errors, means that all pages are * in the correct zone. */ - if (list_empty(&cma_page_list) && !isolation_error_count) + if (list_empty(&movable_page_list) && !isolation_error_count) return ret; - if (!list_empty(&cma_page_list)) { + if (!list_empty(&movable_page_list)) { /* * drop the above get_user_pages reference. */ @@ -1611,12 +1611,12 @@ static long check_and_migrate_cma_pages(struct mm_struct *mm, for (i = 0; i < nr_pages; i++) put_page(pages[i]); - ret = migrate_pages(&cma_page_list, alloc_migration_target, + ret = migrate_pages(&movable_page_list, alloc_migration_target, NULL, (unsigned long)&mtc, MIGRATE_SYNC, - MR_CONTIG_RANGE); + MR_LONGTERM_PIN); if (ret) { - if (!list_empty(&cma_page_list)) - putback_movable_pages(&cma_page_list); + if (!list_empty(&movable_page_list)) + putback_movable_pages(&movable_page_list); return ret > 0 ? -ENOMEM : ret; } @@ -1635,16 +1635,16 @@ static long check_and_migrate_cma_pages(struct mm_struct *mm, goto check_again; } #else -static long check_and_migrate_cma_pages(struct mm_struct *mm, - unsigned long start, - unsigned long nr_pages, - struct page **pages, - struct vm_area_struct **vmas, - unsigned int gup_flags) +static long check_and_migrate_movable_pages(struct mm_struct *mm, + unsigned long start, + unsigned long nr_pages, + struct page **pages, + struct vm_area_struct **vmas, + unsigned int gup_flags) { return nr_pages; } -#endif /* CONFIG_CMA */ +#endif /* CONFIG_MIGRATION */ /* * __gup_longterm_locked() is a wrapper for __get_user_pages_locked which @@ -1668,8 +1668,9 @@ static long __gup_longterm_locked(struct mm_struct *mm, if (gup_flags & FOLL_LONGTERM) { if (rc > 0) - rc = check_and_migrate_cma_pages(mm, start, rc, pages, - vmas, gup_flags); + rc = check_and_migrate_movable_pages(mm, start, rc, + pages, vmas, + gup_flags); memalloc_pin_restore(flags); } return rc; From patchwork Thu Feb 11 16:24:23 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pasha Tatashin X-Patchwork-Id: 12083711 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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 B14EBC433DB for ; Thu, 11 Feb 2021 16:30:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7FECB64E95 for ; Thu, 11 Feb 2021 16:30:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231886AbhBKQaH (ORCPT ); Thu, 11 Feb 2021 11:30:07 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36602 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231956AbhBKQ1j (ORCPT ); Thu, 11 Feb 2021 11:27:39 -0500 Received: from mail-qt1-x834.google.com (mail-qt1-x834.google.com [IPv6:2607:f8b0:4864:20::834]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0198CC061A27 for ; Thu, 11 Feb 2021 08:24:46 -0800 (PST) Received: by mail-qt1-x834.google.com with SMTP id n28so4528168qtv.12 for ; Thu, 11 Feb 2021 08:24:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=soleen.com; s=google; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=1y8YVJPfrTUIiLzCoLZfzLsb38Z+1ZQwX7g2yPLqtWE=; b=BMZBD7oFx42XW1Uk/eIT+ek2yqmO2Unwl542eAk9EtAij5sF54ALjQ+UxIzV6fseqn 9KHoTP/AkRo/I9nUl/bckx72sPe9TsPWqhTnETapUUtoMI91yr0quP6I2g4jL9ElIwQI qlZT7xirvXSEQOXrLZ8Glpk4Dt2Y6sD2Vo7KfitLgkUuUXK0jU1Rhp+kNsDhVjc8oyTr UatAl1MdhuE/8fWIVU9acVXddvE7Yvu1P1HbnVuDAEZ3oRvBX5RSCzPGZplfL9STagRw YC3vR6mguTAhApUEkxNsXoKWoXBOMgXWuvtlZNOD+cHwfHFMlDheS5Kyw2acUXRC6opX Y2aA== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=1y8YVJPfrTUIiLzCoLZfzLsb38Z+1ZQwX7g2yPLqtWE=; b=W5eB/bH+3a2BORjqW53N+wNj3qYxIpb97t/0xpi4H1OPz4FWLhIgEaKMzO6MfZ03Qc 5h8c9YsxpnfVxW4092s7EWQbhJCRk+aChVcXuXBYBzhYZxDWV/7T9XrlEmJgzcryvpv1 /rHD78Xj6lTC7Kl6Uw+PYfG/lTU0noW9zOBJCAkQQ2vGLB+5g27th4LR1TFwFlfN5/oQ JD2F39mZ7XvlLu4BGeQRFeOd4eTruVQWsu/wcl0wwhRTupWXAdN4ddnLMxX9tsaqbNSL IEtVDtTK8+LJ6PxYZlG2FuAosTnuGbE5b8GYyUkjrm6CEgUmhOhatnwTt3pUEcvFXGxX EqIQ== X-Gm-Message-State: AOAM5330uleiE+vACwXB5vX464++59oNZ6PJAFq5AiQbYf+RCT0fH+tU O9T2iwCjTdopTW24Kmy0zgkPJg== X-Google-Smtp-Source: ABdhPJywW3R49OtwqHgSlgYoPuSklhjeeJfwnn3touZTrtXT9dvY7n8wJc0mz/T1j2uyZvz6BoDYwg== X-Received: by 2002:ac8:4d43:: with SMTP id x3mr8211573qtv.17.1613060685225; Thu, 11 Feb 2021 08:24:45 -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 i23sm3831778qtq.42.2021.02.11.08.24.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 11 Feb 2021 08:24:44 -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 v10 10/14] memory-hotplug.rst: add a note about ZONE_MOVABLE and page pinning Date: Thu, 11 Feb 2021 11:24:23 -0500 Message-Id: <20210211162427.618913-11-pasha.tatashin@soleen.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210211162427.618913-1-pasha.tatashin@soleen.com> References: <20210211162427.618913-1-pasha.tatashin@soleen.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Document the special handling of page pinning when ZONE_MOVABLE present. Signed-off-by: Pavel Tatashin Suggested-by: David Hildenbrand Acked-by: Michal Hocko --- Documentation/admin-guide/mm/memory-hotplug.rst | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/Documentation/admin-guide/mm/memory-hotplug.rst b/Documentation/admin-guide/mm/memory-hotplug.rst index 5307f90738aa..05d51d2d8beb 100644 --- a/Documentation/admin-guide/mm/memory-hotplug.rst +++ b/Documentation/admin-guide/mm/memory-hotplug.rst @@ -357,6 +357,15 @@ creates ZONE_MOVABLE as following. Unfortunately, there is no information to show which memory block belongs to ZONE_MOVABLE. This is TBD. +.. note:: + Techniques that rely on long-term pinnings of memory (especially, RDMA and + vfio) are fundamentally problematic with ZONE_MOVABLE and, therefore, memory + hot remove. Pinned pages cannot reside on ZONE_MOVABLE, to guarantee that + memory can still get hot removed - be aware that pinning can fail even if + there is plenty of free memory in ZONE_MOVABLE. In addition, using + ZONE_MOVABLE might make page pinning more expensive, because pages have to be + migrated off that zone first. + .. _memory_hotplug_how_to_offline_memory: How to offline memory From patchwork Thu Feb 11 16:24:24 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pasha Tatashin X-Patchwork-Id: 12083709 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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 4E667C43381 for ; Thu, 11 Feb 2021 16:30:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 28A2964EC0 for ; Thu, 11 Feb 2021 16:30:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231891AbhBKQaE (ORCPT ); Thu, 11 Feb 2021 11:30:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36572 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231951AbhBKQ1j (ORCPT ); Thu, 11 Feb 2021 11:27:39 -0500 Received: from mail-qv1-xf2e.google.com (mail-qv1-xf2e.google.com [IPv6:2607:f8b0:4864:20::f2e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9535BC061A29 for ; Thu, 11 Feb 2021 08:24:47 -0800 (PST) Received: by mail-qv1-xf2e.google.com with SMTP id dr7so1031305qvb.1 for ; Thu, 11 Feb 2021 08:24:47 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=soleen.com; s=google; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=KnIo6b0mEfBi+N6pkBoUNy3tWIMzelUSHiTa3+9/dts=; b=n8Eu1wdTAh9Eu4OjEcbbsCdcAWsoWpPR6r6oYR8mtb7+gOiuwlw5rBoFjWAUF1aD4T TXzqZomyaBngyAVAPOpRH35SWz1FaO7N8eyisU1iXK+yeL/CmG3GjMM0lbDi1VM0RU5Y xl005mxCvoNcjB/gA8lU6/08bS7TVoKdrR9atqFIUZ2MFTaxrnGWK7+GJeJrkaj2eBvn 8DCsb16/e8ik7AkLva5ru4YCK7qz3//jrh0fkfWuQ2cbWV359i9AoN1BOgCZbBmwvJQ9 I2cGyZMZKHROPHbFEIIs6foth/8gNgH54qY6OhsqfuemiSCeodc9J6/bdG1jjwja7/V9 OaKA== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=KnIo6b0mEfBi+N6pkBoUNy3tWIMzelUSHiTa3+9/dts=; b=mm04iBCoOUFjKRAs4l93BysfYye13oZH2AUCentHdwCN6Bxj6/tTUP+8aBFzgC32IG fVuNdCuJrYYpv8zlTGvYpQfpS7UVz72WeLAOMMgoGSewhre/2o2ISHDiyq7zIRwTcwLT 5hrS2G9Z/7VftbJsapwbcoX8fXyNi58DXm/V+MyxKAQGoiqCPgmH/NqGzgmD72fGNiqn hxxr2gaXu/DGhmsG73WIbMjgzeFYEgCwrHU/ci0qFKMjdE/iuEOc1kyISJxZCFKv9c0h YCRVhbfJDKM2kNuzb9AxWLpsgt7r/6TmWhfl7ED/nEsUWpo5839izoRnJHjalNYY9QW4 zE5Q== X-Gm-Message-State: AOAM532pf34dyXwuMXPtIcnl/Lv5FwbYeAIbqPQTVmDeb2Us3YLZ7RL/ Kgb0z5Ml+MohGry2pB2HPlL9lA== X-Google-Smtp-Source: ABdhPJzIeLzlqhbbKblTkU8XD7cXmkgY30iiBxIBBLyWnV0dtEAESq464td/C4isJdlFAK5z34rDsw== X-Received: by 2002:ad4:554c:: with SMTP id v12mr8612729qvy.41.1613060686722; Thu, 11 Feb 2021 08:24:46 -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 i23sm3831778qtq.42.2021.02.11.08.24.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 11 Feb 2021 08:24:46 -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 v10 11/14] mm/gup: change index type to long as it counts pages Date: Thu, 11 Feb 2021 11:24:24 -0500 Message-Id: <20210211162427.618913-12-pasha.tatashin@soleen.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210211162427.618913-1-pasha.tatashin@soleen.com> References: <20210211162427.618913-1-pasha.tatashin@soleen.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org In __get_user_pages_locked() i counts number of pages which should be long, as long is used in all other places to contain number of pages, and 32-bit becomes increasingly small for handling page count proportional values. Signed-off-by: Pavel Tatashin Acked-by: Michal Hocko --- mm/gup.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/gup.c b/mm/gup.c index ced2303dc59e..9d303c8e907f 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -1471,7 +1471,7 @@ static long __get_user_pages_locked(struct mm_struct *mm, unsigned long start, { struct vm_area_struct *vma; unsigned long vm_flags; - int i; + long i; /* calculate required read or write permissions. * If FOLL_FORCE is set, we only require the "MAY" flags. From patchwork Thu Feb 11 16:24:25 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pasha Tatashin X-Patchwork-Id: 12083719 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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 8C680C433E0 for ; Thu, 11 Feb 2021 16:32:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5FB4664EC1 for ; Thu, 11 Feb 2021 16:32:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231651AbhBKQcO (ORCPT ); Thu, 11 Feb 2021 11:32:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37070 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230330AbhBKQaG (ORCPT ); Thu, 11 Feb 2021 11:30:06 -0500 Received: from mail-qv1-xf30.google.com (mail-qv1-xf30.google.com [IPv6:2607:f8b0:4864:20::f30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 27D0EC061A2E for ; Thu, 11 Feb 2021 08:24:49 -0800 (PST) Received: by mail-qv1-xf30.google.com with SMTP id j13so2809516qvu.10 for ; Thu, 11 Feb 2021 08:24:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=soleen.com; s=google; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=cpKhv+EKK6e78H16HEBSNWavBzh4Tq4FHRs4kCXOapI=; b=Q/zr2hj8anGPSh6C0F2Ebq5ffCkchUgt3L9kGNYMoRzIPCqtMxFCJdSzY2bMvmovZm vOjzY7TUskWJAfZgJfep4g7KZWCqHNo2EgfTkuExlCX4Jwiuu5DIZPg6DULIU96TMLQQ vag1MJ7HB7wTcusoEAg2fHSVmcdUT/Xz+ogzOAKyiYM0NPirvkacTKQySDhDBAX3OwEW rUfDprsSDnDV3zLgO4gUNh6KlMn8yd2nB14/heb7TrigSjJO9xNUGjhFXHS/7w91fgOJ LZ0sviLI/I055yifbYZYiupHUCpib9JWNsYKiqGsUtdlY/s/vZNZdWPVC+zPx7uZyRa6 kV0Q== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=cpKhv+EKK6e78H16HEBSNWavBzh4Tq4FHRs4kCXOapI=; b=NTzG3NSPoEmUbCOGlyrXtlHgOMeelV/pjNzEiwTwnmezEY3YBr9GxIpsFhNRo2NwPs Gu6RjaoZcvzJ+4NVf1JgmBk7wuIUzIgSn5wK7nJer68ckgx7hiVXXFk/duCb3dmpryl+ u30dJ4CXAWVeke+crLhlmUW2H32PZCEsBO5t11TAYk4aEOh9GX1ZaEEpaEvoZ363XUOh lD5GwWa1camGW9/o52oqDVZhUGikdrUO4UshWPvHvyhNN0BqOEn62BktnCusgE0eUWiQ FDIR4UQaH2KuEpEF7G2UTauZoaxY4aJlJpez+PL2ArsBmcfy77MwHDMxgP6fkQ4mHSac JFKQ== X-Gm-Message-State: AOAM532dFUqYL3gTvbHBeBMtOyRoUsM+FXK3qS4nfjvrnT90Aq++qUf6 kih8kAvWEVYeTZ9hSvjaSxEB1Q== X-Google-Smtp-Source: ABdhPJzNOOawfToxmUWh4jXkiTdptEunlNizEe0saOS0ErL6vAR5LsLrDthsVikLiULWL/Ws+sVd6g== X-Received: by 2002:a0c:dc8e:: with SMTP id n14mr8483319qvk.6.1613060688387; Thu, 11 Feb 2021 08:24:48 -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 i23sm3831778qtq.42.2021.02.11.08.24.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 11 Feb 2021 08:24:47 -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 v10 12/14] mm/gup: longterm pin migration cleanup Date: Thu, 11 Feb 2021 11:24:25 -0500 Message-Id: <20210211162427.618913-13-pasha.tatashin@soleen.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210211162427.618913-1-pasha.tatashin@soleen.com> References: <20210211162427.618913-1-pasha.tatashin@soleen.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org When pages are longterm pinned, we must migrated them out of movable zone. The function that migrates them has a hidden loop with goto. The loop is to retry on isolation failures, and after successful migration. Make this code better by moving this loop to the caller. Signed-off-by: Pavel Tatashin Reviewed-by: Jason Gunthorpe --- mm/gup.c | 93 ++++++++++++++++++++++---------------------------------- 1 file changed, 37 insertions(+), 56 deletions(-) diff --git a/mm/gup.c b/mm/gup.c index 9d303c8e907f..e3df4e0813d6 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -1541,27 +1541,28 @@ struct page *get_dump_page(unsigned long addr) #endif /* CONFIG_ELF_CORE */ #ifdef CONFIG_MIGRATION -static long check_and_migrate_movable_pages(struct mm_struct *mm, - unsigned long start, - unsigned long nr_pages, +/* + * Check whether all pages are pinnable, if so return number of pages. If some + * pages are not pinnable, migrate them, and unpin all pages. Return zero if + * pages were migrated, or if some pages were not successfully isolated. + * Return negative error if migration fails. + */ +static long check_and_migrate_movable_pages(unsigned long nr_pages, struct page **pages, - struct vm_area_struct **vmas, unsigned int gup_flags) { - unsigned long i, isolation_error_count; - bool drain_allow; + unsigned long i; + unsigned long isolation_error_count = 0; + bool drain_allow = true; LIST_HEAD(movable_page_list); - long ret = nr_pages; - struct page *prev_head, *head; + long ret = 0; + struct page *prev_head = NULL; + struct page *head; struct migration_target_control mtc = { .nid = NUMA_NO_NODE, .gfp_mask = GFP_USER | __GFP_NOWARN, }; -check_again: - prev_head = NULL; - isolation_error_count = 0; - drain_allow = true; for (i = 0; i < nr_pages; i++) { head = compound_head(pages[i]); if (head == prev_head) @@ -1599,47 +1600,27 @@ static long check_and_migrate_movable_pages(struct mm_struct *mm, * in the correct zone. */ if (list_empty(&movable_page_list) && !isolation_error_count) - return ret; + return nr_pages; + if (gup_flags & FOLL_PIN) { + unpin_user_pages(pages, nr_pages); + } else { + for (i = 0; i < nr_pages; i++) + put_page(pages[i]); + } if (!list_empty(&movable_page_list)) { - /* - * drop the above get_user_pages reference. - */ - if (gup_flags & FOLL_PIN) - unpin_user_pages(pages, nr_pages); - else - for (i = 0; i < nr_pages; i++) - put_page(pages[i]); - ret = migrate_pages(&movable_page_list, alloc_migration_target, NULL, (unsigned long)&mtc, MIGRATE_SYNC, MR_LONGTERM_PIN); - if (ret) { - if (!list_empty(&movable_page_list)) - putback_movable_pages(&movable_page_list); - return ret > 0 ? -ENOMEM : ret; - } - - /* We unpinned pages before migration, pin them again */ - ret = __get_user_pages_locked(mm, start, nr_pages, pages, vmas, - NULL, gup_flags); - if (ret <= 0) - return ret; - nr_pages = ret; + if (ret && !list_empty(&movable_page_list)) + putback_movable_pages(&movable_page_list); } - /* - * check again because pages were unpinned, and we also might have - * had isolation errors and need more pages to migrate. - */ - goto check_again; + return ret > 0 ? -ENOMEM : ret; } #else -static long check_and_migrate_movable_pages(struct mm_struct *mm, - unsigned long start, - unsigned long nr_pages, +static long check_and_migrate_movable_pages(unsigned long nr_pages, struct page **pages, - struct vm_area_struct **vmas, unsigned int gup_flags) { return nr_pages; @@ -1657,22 +1638,22 @@ static long __gup_longterm_locked(struct mm_struct *mm, struct vm_area_struct **vmas, unsigned int gup_flags) { - unsigned long flags = 0; + unsigned int flags; long rc; - if (gup_flags & FOLL_LONGTERM) - flags = memalloc_pin_save(); - - rc = __get_user_pages_locked(mm, start, nr_pages, pages, vmas, NULL, - gup_flags); + if (!(gup_flags & FOLL_LONGTERM)) + return __get_user_pages_locked(mm, start, nr_pages, pages, vmas, + NULL, gup_flags); + flags = memalloc_pin_save(); + do { + rc = __get_user_pages_locked(mm, start, nr_pages, pages, vmas, + NULL, gup_flags); + if (rc <= 0) + break; + rc = check_and_migrate_movable_pages(rc, pages, gup_flags); + } while (!rc); + memalloc_pin_restore(flags); - if (gup_flags & FOLL_LONGTERM) { - if (rc > 0) - rc = check_and_migrate_movable_pages(mm, start, rc, - pages, vmas, - gup_flags); - memalloc_pin_restore(flags); - } return rc; } From patchwork Thu Feb 11 16:24:26 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pasha Tatashin X-Patchwork-Id: 12083723 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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 09843C433E0 for ; Thu, 11 Feb 2021 16:33:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C856864EC1 for ; Thu, 11 Feb 2021 16:33:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229879AbhBKQcZ (ORCPT ); Thu, 11 Feb 2021 11:32:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37668 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231640AbhBKQaO (ORCPT ); Thu, 11 Feb 2021 11:30:14 -0500 Received: from mail-qk1-x731.google.com (mail-qk1-x731.google.com [IPv6:2607:f8b0:4864:20::731]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 913A9C061A31 for ; Thu, 11 Feb 2021 08:24:50 -0800 (PST) Received: by mail-qk1-x731.google.com with SMTP id f17so2424190qkl.5 for ; Thu, 11 Feb 2021 08:24:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=soleen.com; s=google; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=Ca95TMJT4ShVUsz7drjIPNjU47Yiarr1AByU+uGNnGI=; b=UAEKzaBmpdpGJPDTslvYbeTKzc+Cl8dL29/mrc5M0LH+FkS1LQVSlP395GOW8df8ix 2gIduDePZ+27EXjens+EPL19sNzgU0NEWkJ/yCGxwqbDfmy+MNlP+GlPPBOpYWWfqz7R wErE9uN+IJZseCuQHcPMn0XO7fHkiFBOX2b63/yKYcZTy+dtK1HvQNXMYPuXjwqdXaGj KOWDk/JyDst2nrRfkQl+aWd53zVTfts1PszjNSzUOR0MrFDxAry/IgjYczLYRsSJaHyB dhiqh1/yntx7YtScWKu/MfEtoXp55u5RySm0PWUzwJiLMMPbXx17IkvQ8BjK5yiCNC0b h4Qw== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=Ca95TMJT4ShVUsz7drjIPNjU47Yiarr1AByU+uGNnGI=; b=NDOkpBYnL+JxhBilnIZI5svVccxerjgDPq3ZOwF190BlNwDu8WoNWHmdhJw4d/vFLe shbBVCwm5zH1NZvaxLXlfOgW+LM5NgIgvq1W06Ww/k3C+iYHmgrYze2MS5Q5eV0KbZHF odavWT4SeeebD/z60hz57/oA/tvK7twlHQ+fkYiVF2nWVVqR5CRZ3LqwQSfO+BfXflQQ lEPf4LPP2rh3gwk48BsNPn4eDegxgyjUQ9c9ovRHPG8221YGmvfANfzuK4Rhrw0teux6 a+ZOJWvaK72lPZzhtFEXBqcohnHxRwQfNLYXvASp6Zr80TOnwLklX8cjeAcz07yY7oME nBoA== X-Gm-Message-State: AOAM531sdvt763CmRBpmZlc4YVCtj9teOCeTqBdyXT3W4Ry7smXq1fkB cc6F0p//Grirk0Wmc1pGmMhHgQ== X-Google-Smtp-Source: ABdhPJwZIK99uXBH+5f+4PTL9HxSVwQu7nbwQqYusHIJqDDQiVz1HIHw9tUUE4Phj0PG69wIFw8dRw== X-Received: by 2002:a37:49c4:: with SMTP id w187mr8918667qka.444.1613060689820; Thu, 11 Feb 2021 08:24:49 -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 i23sm3831778qtq.42.2021.02.11.08.24.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 11 Feb 2021 08:24:49 -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 v10 13/14] selftests/vm: gup_test: fix test flag Date: Thu, 11 Feb 2021 11:24:26 -0500 Message-Id: <20210211162427.618913-14-pasha.tatashin@soleen.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210211162427.618913-1-pasha.tatashin@soleen.com> References: <20210211162427.618913-1-pasha.tatashin@soleen.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org In gup_test both gup_flags and test_flags use the same flags field. This is broken. Farther, in the actual gup_test.c all the passed gup_flags are erased and unconditionally replaced with FOLL_WRITE. Which means that test_flags are ignored, and code like this always performs pin dump test: 155 if (gup->flags & GUP_TEST_FLAG_DUMP_PAGES_USE_PIN) 156 nr = pin_user_pages(addr, nr, gup->flags, 157 pages + i, NULL); 158 else 159 nr = get_user_pages(addr, nr, gup->flags, 160 pages + i, NULL); 161 break; Add a new test_flags field, to allow raw gup_flags to work. Add a new subcommand for DUMP_USER_PAGES_TEST to specify that pin test should be performed. Remove unconditional overwriting of gup_flags via FOLL_WRITE. But, preserve the previous behaviour where FOLL_WRITE was the default flag, and add a new option "-W" to unset FOLL_WRITE. Rename flags with gup_flags. With the fix, dump works like this: root@virtme:/# gup_test -c ---- page #0, starting from user virt addr: 0x7f8acb9e4000 page:00000000d3d2ee27 refcount:2 mapcount:1 mapping:0000000000000000 index:0x0 pfn:0x100bcf anon flags: 0x300000000080016(referenced|uptodate|lru|swapbacked) raw: 0300000000080016 ffffd0e204021608 ffffd0e208df2e88 ffff8ea04243ec61 raw: 0000000000000000 0000000000000000 0000000200000000 0000000000000000 page dumped because: gup_test: dump_pages() test DUMP_USER_PAGES_TEST: done root@virtme:/# gup_test -c -p ---- page #0, starting from user virt addr: 0x7fd19701b000 page:00000000baed3c7d refcount:1025 mapcount:1 mapping:0000000000000000 index:0x0 pfn:0x108008 anon flags: 0x300000000080014(uptodate|lru|swapbacked) raw: 0300000000080014 ffffd0e204200188 ffffd0e205e09088 ffff8ea04243ee71 raw: 0000000000000000 0000000000000000 0000040100000000 0000000000000000 page dumped because: gup_test: dump_pages() test DUMP_USER_PAGES_TEST: done Refcount shows the difference between pin vs no-pin case. Also change type of nr from int to long, as it counts number of pages. Signed-off-by: Pavel Tatashin Reviewed-by: John Hubbard --- mm/gup_test.c | 23 ++++++++++------------- mm/gup_test.h | 3 ++- tools/testing/selftests/vm/gup_test.c | 15 +++++++++++---- 3 files changed, 23 insertions(+), 18 deletions(-) diff --git a/mm/gup_test.c b/mm/gup_test.c index e3cf78e5873e..a6ed1c877679 100644 --- a/mm/gup_test.c +++ b/mm/gup_test.c @@ -94,7 +94,7 @@ static int __gup_test_ioctl(unsigned int cmd, { ktime_t start_time, end_time; unsigned long i, nr_pages, addr, next; - int nr; + long nr; struct page **pages; int ret = 0; bool needs_mmap_lock = @@ -126,37 +126,34 @@ static int __gup_test_ioctl(unsigned int cmd, nr = (next - addr) / PAGE_SIZE; } - /* Filter out most gup flags: only allow a tiny subset here: */ - gup->flags &= FOLL_WRITE; - switch (cmd) { case GUP_FAST_BENCHMARK: - nr = get_user_pages_fast(addr, nr, gup->flags, + nr = get_user_pages_fast(addr, nr, gup->gup_flags, pages + i); break; case GUP_BASIC_TEST: - nr = get_user_pages(addr, nr, gup->flags, pages + i, + nr = get_user_pages(addr, nr, gup->gup_flags, pages + i, NULL); break; case PIN_FAST_BENCHMARK: - nr = pin_user_pages_fast(addr, nr, gup->flags, + nr = pin_user_pages_fast(addr, nr, gup->gup_flags, pages + i); break; case PIN_BASIC_TEST: - nr = pin_user_pages(addr, nr, gup->flags, pages + i, + nr = pin_user_pages(addr, nr, gup->gup_flags, pages + i, NULL); break; case PIN_LONGTERM_BENCHMARK: nr = pin_user_pages(addr, nr, - gup->flags | FOLL_LONGTERM, + gup->gup_flags | FOLL_LONGTERM, pages + i, NULL); break; case DUMP_USER_PAGES_TEST: - if (gup->flags & GUP_TEST_FLAG_DUMP_PAGES_USE_PIN) - nr = pin_user_pages(addr, nr, gup->flags, + if (gup->test_flags & GUP_TEST_FLAG_DUMP_PAGES_USE_PIN) + nr = pin_user_pages(addr, nr, gup->gup_flags, pages + i, NULL); else - nr = get_user_pages(addr, nr, gup->flags, + nr = get_user_pages(addr, nr, gup->gup_flags, pages + i, NULL); break; default: @@ -187,7 +184,7 @@ static int __gup_test_ioctl(unsigned int cmd, start_time = ktime_get(); - put_back_pages(cmd, pages, nr_pages, gup->flags); + put_back_pages(cmd, pages, nr_pages, gup->test_flags); end_time = ktime_get(); gup->put_delta_usec = ktime_us_delta(end_time, start_time); diff --git a/mm/gup_test.h b/mm/gup_test.h index 90a6713d50eb..887ac1d5f5bc 100644 --- a/mm/gup_test.h +++ b/mm/gup_test.h @@ -21,7 +21,8 @@ struct gup_test { __u64 addr; __u64 size; __u32 nr_pages_per_call; - __u32 flags; + __u32 gup_flags; + __u32 test_flags; /* * Each non-zero entry is the number of the page (1-based: first page is * page 1, so that zero entries mean "do nothing") from the .addr base. diff --git a/tools/testing/selftests/vm/gup_test.c b/tools/testing/selftests/vm/gup_test.c index 6c6336dd3b7f..943cc2608dc2 100644 --- a/tools/testing/selftests/vm/gup_test.c +++ b/tools/testing/selftests/vm/gup_test.c @@ -37,13 +37,13 @@ int main(int argc, char **argv) { struct gup_test gup = { 0 }; unsigned long size = 128 * MB; - int i, fd, filed, opt, nr_pages = 1, thp = -1, repeats = 1, write = 0; + int i, fd, filed, opt, nr_pages = 1, thp = -1, repeats = 1, write = 1; unsigned long cmd = GUP_FAST_BENCHMARK; int flags = MAP_PRIVATE; char *file = "/dev/zero"; char *p; - while ((opt = getopt(argc, argv, "m:r:n:F:f:abctTLUuwSH")) != -1) { + while ((opt = getopt(argc, argv, "m:r:n:F:f:abctTLUuwWSHp")) != -1) { switch (opt) { case 'a': cmd = PIN_FAST_BENCHMARK; @@ -65,9 +65,13 @@ int main(int argc, char **argv) */ gup.which_pages[0] = 1; break; + case 'p': + /* works only with DUMP_USER_PAGES_TEST */ + gup.test_flags |= GUP_TEST_FLAG_DUMP_PAGES_USE_PIN; + break; case 'F': /* strtol, so you can pass flags in hex form */ - gup.flags = strtol(optarg, 0, 0); + gup.gup_flags = strtol(optarg, 0, 0); break; case 'm': size = atoi(optarg) * MB; @@ -93,6 +97,9 @@ int main(int argc, char **argv) case 'w': write = 1; break; + case 'W': + write = 0; + break; case 'f': file = optarg; break; @@ -140,7 +147,7 @@ int main(int argc, char **argv) gup.nr_pages_per_call = nr_pages; if (write) - gup.flags |= FOLL_WRITE; + gup.gup_flags |= FOLL_WRITE; fd = open("/sys/kernel/debug/gup_test", O_RDWR); if (fd == -1) { From patchwork Thu Feb 11 16:24:27 2021 Content-Type: text/plain; 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[73.69.118.222]) by smtp.gmail.com with ESMTPSA id i23sm3831778qtq.42.2021.02.11.08.24.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 11 Feb 2021 08:24:50 -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 v10 14/14] selftests/vm: gup_test: test faulting in kernel, and verify pinnable pages Date: Thu, 11 Feb 2021 11:24:27 -0500 Message-Id: <20210211162427.618913-15-pasha.tatashin@soleen.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210211162427.618913-1-pasha.tatashin@soleen.com> References: <20210211162427.618913-1-pasha.tatashin@soleen.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org When pages are pinned they can be faulted in userland and migrated, and they can be faulted right in kernel without migration. In either case, the pinned pages must end-up being pinnable (not movable). Add a new test to gup_test, to help verify that the gup/pup (get_user_pages() / pin_user_pages()) behavior with respect to pinnable and movable pages is reasonable and correct. Specifically, provide a way to: 1) Verify that only "pinnable" pages are pinned. This is checked automatically for you. 2) Verify that gup/pup performance is reasonable. This requires comparing benchmarks between doing gup/pup on pages that have been pre-faulted in from user space, vs. doing gup/pup on pages that are not faulted in until gup/pup time (via FOLL_TOUCH). This decision is controlled with the new -z command line option. Signed-off-by: Pavel Tatashin Reviewed-by: John Hubbard --- mm/gup_test.c | 6 ++++++ tools/testing/selftests/vm/gup_test.c | 23 +++++++++++++++++++---- 2 files changed, 25 insertions(+), 4 deletions(-) diff --git a/mm/gup_test.c b/mm/gup_test.c index a6ed1c877679..d974dec19e1c 100644 --- a/mm/gup_test.c +++ b/mm/gup_test.c @@ -52,6 +52,12 @@ static void verify_dma_pinned(unsigned int cmd, struct page **pages, dump_page(page, "gup_test failure"); break; + } else if (cmd == PIN_LONGTERM_BENCHMARK && + WARN(!is_pinnable_page(page), + "pages[%lu] is NOT pinnable but pinned\n", + i)) { + dump_page(page, "gup_test failure"); + break; } } break; diff --git a/tools/testing/selftests/vm/gup_test.c b/tools/testing/selftests/vm/gup_test.c index 943cc2608dc2..1e662d59c502 100644 --- a/tools/testing/selftests/vm/gup_test.c +++ b/tools/testing/selftests/vm/gup_test.c @@ -13,6 +13,7 @@ /* Just the flags we need, copied from mm.h: */ #define FOLL_WRITE 0x01 /* check pte is writable */ +#define FOLL_TOUCH 0x02 /* mark page accessed */ static char *cmd_to_str(unsigned long cmd) { @@ -39,11 +40,11 @@ int main(int argc, char **argv) unsigned long size = 128 * MB; int i, fd, filed, opt, nr_pages = 1, thp = -1, repeats = 1, write = 1; unsigned long cmd = GUP_FAST_BENCHMARK; - int flags = MAP_PRIVATE; + int flags = MAP_PRIVATE, touch = 0; char *file = "/dev/zero"; char *p; - while ((opt = getopt(argc, argv, "m:r:n:F:f:abctTLUuwWSHp")) != -1) { + while ((opt = getopt(argc, argv, "m:r:n:F:f:abctTLUuwWSHpz")) != -1) { switch (opt) { case 'a': cmd = PIN_FAST_BENCHMARK; @@ -110,6 +111,10 @@ int main(int argc, char **argv) case 'H': flags |= (MAP_HUGETLB | MAP_ANONYMOUS); break; + case 'z': + /* fault pages in gup, do not fault in userland */ + touch = 1; + break; default: return -1; } @@ -167,8 +172,18 @@ int main(int argc, char **argv) else if (thp == 0) madvise(p, size, MADV_NOHUGEPAGE); - for (; (unsigned long)p < gup.addr + size; p += PAGE_SIZE) - p[0] = 0; + /* + * FOLL_TOUCH, in gup_test, is used as an either/or case: either + * fault pages in from the kernel via FOLL_TOUCH, or fault them + * in here, from user space. This allows comparison of performance + * between those two cases. + */ + if (touch) { + gup.gup_flags |= FOLL_TOUCH; + } else { + for (; (unsigned long)p < gup.addr + size; p += PAGE_SIZE) + p[0] = 0; + } /* Only report timing information on the *_BENCHMARK commands: */ if ((cmd == PIN_FAST_BENCHMARK) || (cmd == GUP_FAST_BENCHMARK) ||