From patchwork Wed Aug 23 13:13:19 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexandru Elisei X-Patchwork-Id: 13362316 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 553AAEE49A0 for ; Wed, 23 Aug 2023 13:15:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235539AbjHWNPQ (ORCPT ); Wed, 23 Aug 2023 09:15:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35870 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235534AbjHWNPP (ORCPT ); Wed, 23 Aug 2023 09:15:15 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 54FCA170E; Wed, 23 Aug 2023 06:14:52 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 919B61576; Wed, 23 Aug 2023 06:15:27 -0700 (PDT) Received: from e121798.cable.virginm.net (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 415F23F740; Wed, 23 Aug 2023 06:14:41 -0700 (PDT) From: Alexandru Elisei To: catalin.marinas@arm.com, will@kernel.org, oliver.upton@linux.dev, maz@kernel.org, james.morse@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, arnd@arndb.de, akpm@linux-foundation.org, mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com, mhiramat@kernel.org, rppt@kernel.org, hughd@google.com Cc: pcc@google.com, steven.price@arm.com, anshuman.khandual@arm.com, vincenzo.frascino@arm.com, david@redhat.com, eugenis@google.com, kcc@google.com, hyesoo.yu@samsung.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kvmarm@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-trace-kernel@vger.kernel.org Subject: [PATCH RFC 06/37] mm: page_alloc: Allocate from movable pcp lists only if ALLOC_FROM_METADATA Date: Wed, 23 Aug 2023 14:13:19 +0100 Message-Id: <20230823131350.114942-7-alexandru.elisei@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230823131350.114942-1-alexandru.elisei@arm.com> References: <20230823131350.114942-1-alexandru.elisei@arm.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-trace-kernel@vger.kernel.org pcp lists keep MIGRATE_METADATA pages on the MIGRATE_MOVABLE list. Make sure pages from the movable list are allocated only when the ALLOC_FROM_METADATA alloc flag is set, as otherwise the page allocator could end up allocating a metadata page when that page cannot be used. __alloc_pages_bulk() sidesteps rmqueue() and calls __rmqueue_pcplist() directly. Add a check for the flag before calling __rmqueue_pcplist(), and fallback to __alloc_pages() if the check is false. Note that CMA isn't a problem for __alloc_pages_bulk(): an allocation can always use CMA pages if the requested migratetype is MIGRATE_MOVABLE, which is not the case with MIGRATE_METADATA pages. Signed-off-by: Alexandru Elisei --- mm/page_alloc.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 829134a4dfa8..a693e23c4733 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2845,11 +2845,16 @@ struct page *rmqueue(struct zone *preferred_zone, if (likely(pcp_allowed_order(order))) { /* - * MIGRATE_MOVABLE pcplist could have the pages on CMA area and - * we need to skip it when CMA area isn't allowed. + * PCP lists keep MIGRATE_CMA/MIGRATE_METADATA pages on the same + * movable list. Make sure it's allowed to allocate both type of + * pages before allocating from the movable list. */ - if (!IS_ENABLED(CONFIG_CMA) || alloc_flags & ALLOC_CMA || - migratetype != MIGRATE_MOVABLE) { + bool movable_allowed = (!IS_ENABLED(CONFIG_CMA) || + (alloc_flags & ALLOC_CMA)) && + (!IS_ENABLED(CONFIG_MEMORY_METADATA) || + (alloc_flags & ALLOC_FROM_METADATA)); + + if (migratetype != MIGRATE_MOVABLE || movable_allowed) { page = rmqueue_pcplist(preferred_zone, zone, order, migratetype, alloc_flags); if (likely(page)) @@ -4388,6 +4393,14 @@ unsigned long __alloc_pages_bulk(gfp_t gfp, int preferred_nid, goto out; gfp = alloc_gfp; + /* + * pcp lists puts MIGRATE_METADATA on the MIGRATE_MOVABLE list, don't + * use pcp if allocating metadata pages is not allowed. + */ + if (metadata_storage_enabled() && ac.migratetype == MIGRATE_MOVABLE && + !(alloc_flags & ALLOC_FROM_METADATA)) + goto failed; + /* Find an allowed local zone that meets the low watermark. */ for_each_zone_zonelist_nodemask(zone, z, ac.zonelist, ac.highest_zoneidx, ac.nodemask) { unsigned long mark;