From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8D90DC41513 for ; Mon, 7 Aug 2023 16:44:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231574AbjHGQoI (ORCPT ); Mon, 7 Aug 2023 12:44:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51538 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231584AbjHGQoH (ORCPT ); Mon, 7 Aug 2023 12:44:07 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BB2FF172B for ; Mon, 7 Aug 2023 09:44:05 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 4711361F6D for ; Mon, 7 Aug 2023 16:44:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9D754C433C7; Mon, 7 Aug 2023 16:44:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1691426644; bh=+7f/aOx+aLmPATpJtC+ui9Kx6tJWzYPgI3faHUqK7yA=; h=Date:To:From:Subject:From; b=IgiYxiHsZaZ7nyK7/WCd06cbsHLa0BqncyXovJS9uAfvHQywy8n8Sn2Zu2/fCqf+Q lTycark6vlvUpDGU8SRyiuaPTgcJQRBjujMS7v+fZzswgOeB7ypcm5RUQQ3U0C/dVT lCqPtjqMDbpDMXKrpBLqbp2wxAGD1VWCVel6dDWg= Date: Mon, 07 Aug 2023 09:44:03 -0700 To: mm-commits@vger.kernel.org, yuzhao@google.com, willy@infradead.org, wangkefeng.wang@huawei.com, vishal.moola@gmail.com, shy828301@gmail.com, ryan.roberts@arm.com, minchan@kernel.org, david@redhat.com, fengwei.yin@intel.com, akpm@linux-foundation.org From: Andrew Morton Subject: [to-be-updated] madvise-madvise_cold_or_pageout_pte_range-dont-use-mapcount-against-large-folio-for-sharing-check.patch removed from -mm tree Message-Id: <20230807164404.9D754C433C7@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The quilt patch titled Subject: madvise:madvise_cold_or_pageout_pte_range(): don't use mapcount() against large folio for sharing check has been removed from the -mm tree. Its filename was madvise-madvise_cold_or_pageout_pte_range-dont-use-mapcount-against-large-folio-for-sharing-check.patch This patch was dropped because an updated version will be merged ------------------------------------------------------ From: Yin Fengwei Subject: madvise:madvise_cold_or_pageout_pte_range(): don't use mapcount() against large folio for sharing check Date: Sat, 29 Jul 2023 00:13:55 +0800 Patch series "don't use mapcount() to check large folio sharing". In madvise_cold_or_pageout_pte_range() and madvise_free_pte_range(), folio_mapcount() is used to check whether the folio is shared. But it's not correct as folio_mapcount() returns total mapcount of large folio. Use folio_estimated_sharers() here as the estimated number is enough. This patch (of 3): Commit 07e8c82b5eff ("madvise: convert madvise_cold_or_pageout_pte_range() to use folios") replaced the page_mapcount() with folio_mapcount() to check whether the folio is shared by other mapping. But it's not correct for large folio. folio_mapcount() returns the total mapcount of large folio which is not suitable to detect whether the folio is shared. Use folio_estimated_sharers() which returns a estimated number of shares. That means it's not 100% correct. But it should be OK for madvise case here. Link: https://lkml.kernel.org/r/20230728161356.1784568-1-fengwei.yin@intel.com Link: https://lkml.kernel.org/r/20230728161356.1784568-2-fengwei.yin@intel.com Fixes: 07e8c82b5eff ("madvise: convert madvise_cold_or_pageout_pte_range() to use folios") Signed-off-by: Yin Fengwei Reviewed-by: Yu Zhao Reviewed-by: Ryan Roberts Cc: David Hildenbrand Cc: Kefeng Wang Cc: Matthew Wilcox (Oracle) Cc: Minchan Kim Cc: Vishal Moola (Oracle) Cc: Yang Shi Signed-off-by: Andrew Morton --- mm/madvise.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/mm/madvise.c~madvise-madvise_cold_or_pageout_pte_range-dont-use-mapcount-against-large-folio-for-sharing-check +++ a/mm/madvise.c @@ -384,7 +384,7 @@ static int madvise_cold_or_pageout_pte_r folio = pfn_folio(pmd_pfn(orig_pmd)); /* Do not interfere with other mappings of this folio */ - if (folio_mapcount(folio) != 1) + if (folio_estimated_sharers(folio) != 1) goto huge_unlock; if (pageout_anon_only_filter && !folio_test_anon(folio)) @@ -460,7 +460,7 @@ regular_folio: if (folio_test_large(folio)) { int err; - if (folio_mapcount(folio) != 1) + if (folio_estimated_sharers(folio) != 1) break; if (pageout_anon_only_filter && !folio_test_anon(folio)) break; _ Patches currently in -mm which might be from fengwei.yin@intel.com are madvise-madvise_free_huge_pmd-dont-use-mapcount-against-large-folio-for-sharing-check.patch madvise-madvise_free_pte_range-dont-use-mapcount-against-large-folio-for-sharing-check.patch filemap-add-filemap_map_folio_range.patch rmap-add-folio_add_file_rmap_range.patch mm-convert-do_set_pte-to-set_pte_range.patch filemap-batch-pte-mappings.patch