From patchwork Mon Jan 25 19:47:41 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pasha Tatashin X-Patchwork-Id: 12044237 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=-16.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 BE239C433E6 for ; Mon, 25 Jan 2021 19:48:03 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 4786E22525 for ; Mon, 25 Jan 2021 19:48:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4786E22525 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=soleen.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id D7CE38D0030; Mon, 25 Jan 2021 14:48:01 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id C8DBB8D0023; Mon, 25 Jan 2021 14:48:01 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B2D878D0030; Mon, 25 Jan 2021 14:48:01 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0040.hostedemail.com [216.40.44.40]) by kanga.kvack.org (Postfix) with ESMTP id 9D0F08D0023 for ; Mon, 25 Jan 2021 14:48:01 -0500 (EST) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 64EE1180AE7F3 for ; Mon, 25 Jan 2021 19:48:01 +0000 (UTC) X-FDA: 77745333162.25.bikes84_3a13bb027588 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin25.hostedemail.com (Postfix) with ESMTP id 369AE1804E3A0 for ; Mon, 25 Jan 2021 19:48:01 +0000 (UTC) X-HE-Tag: bikes84_3a13bb027588 X-Filterd-Recvd-Size: 7167 Received: from mail-qk1-f173.google.com (mail-qk1-f173.google.com [209.85.222.173]) by imf14.hostedemail.com (Postfix) with ESMTP for ; Mon, 25 Jan 2021 19:48:00 +0000 (UTC) Received: by mail-qk1-f173.google.com with SMTP id r77so13526569qka.12 for ; Mon, 25 Jan 2021 11:48:00 -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=g2firNhV/7kB7YU7cH9BNSgXaQWIxvW5HlS98FNnYEs=; b=AMPWTTnTQtQrH0f812HX8J/XenqFD0LhTJ4uvra0Yc82gbHE9JUqY698LNtS80BE7R HR+xMh6u82Ttl2HRET2KJJgXpfY0HAW1XAkqnXoYkorW9DdsIXlDDaKOJsRmrtQ2/nEG Dmb4GCZxUK9zEwlcH3WDx/URO0SVMy0zcD9v2FKoTwgARO1MZ/OlQM2BSz/juCLIjm3+ Ea0mQylNJ+kUPUNcC5yvUomLFphaeUQkqGKv5Qe3PZZaI9d8ehH1Z1VgrSynAksIDQ8Q 1KdzNIxtcFbSYYmlQkrBgCfYAOIWMyB8X7sV+6aCuasMoW4NW0MbgSIrAIc2CBltCiiY S4Bw== 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=g2firNhV/7kB7YU7cH9BNSgXaQWIxvW5HlS98FNnYEs=; b=QTmKP1VNumhVBu0LR9xtdySWwtatw3pqsFarHbARC8QQWuiDCSPnw7ypmhPs3068ht 7//HUX62As3kR9Y+PMQAN6t6O1vWnGT4VRMOmKAkHE26GSs3MYZQB3hXS6EHuUh9nB3L RVR+6qAbMs4z7/3Mfv1VE5DNjgPtUxhz3Nl8n7dxviwhxPIgACw3PEzyt9+Hd7/eYLjN 9EGVbvGA87VNG+de4Pc4dEZT9wb7hju+JLGwY2go6zFXQM6QXW9ju+foIfMTyJy1K63s /lacSjKFFE2y7YWYvdZSiedseDdl9oIUec/lBbmTdmOJSiVq6m1FzxGKs0VinoT29cQZ GjUA== X-Gm-Message-State: AOAM533A+Y3uY3LughH8F8ceb+ZKyT32/TJGZ6ow0uTjDJGyFVD7iUQ/ wS766u9uTe60D39SbEeGqrXcLA== X-Google-Smtp-Source: ABdhPJwYEL3DoI+pABS4RBJJVNs455EMYUvP8bvQI2v1Jkb8103rBVGefY9aunaJRQVj9v3yEHgwng== X-Received: by 2002:a37:4554:: with SMTP id s81mr2369392qka.323.1611604080206; Mon, 25 Jan 2021 11:48:00 -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 c12sm12121569qtq.76.2021.01.25.11.47.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 25 Jan 2021 11:47:59 -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 v8 04/14] mm/gup: check for isolation errors Date: Mon, 25 Jan 2021 14:47:41 -0500 Message-Id: <20210125194751.1275316-5-pasha.tatashin@soleen.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210125194751.1275316-1-pasha.tatashin@soleen.com> References: <20210125194751.1275316-1-pasha.tatashin@soleen.com> MIME-Version: 1.0 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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 88ce41f41543..7ecca2d66dff 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -1555,8 +1555,8 @@ 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; @@ -1567,6 +1567,8 @@ 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) @@ -1578,25 +1580,35 @@ 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. @@ -1616,23 +1628,19 @@ 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,