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 5D1FCC54EAA for ; Tue, 31 Jan 2023 00:14:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229986AbjAaAO3 (ORCPT ); Mon, 30 Jan 2023 19:14:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50976 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229927AbjAaAO3 (ORCPT ); Mon, 30 Jan 2023 19:14:29 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9D3B440EB for ; Mon, 30 Jan 2023 16:14:27 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 3627361329 for ; Tue, 31 Jan 2023 00:14:27 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 86B43C433EF; Tue, 31 Jan 2023 00:14:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1675124066; bh=3nvxK53/wsaEY56CpZCkNgLlzFW9UbxINdWpwRSIBXI=; h=Date:To:From:Subject:From; b=gzb0JGutZpoIY0LGJdpk1LgG9OTTmWRffoePpOOqEtd0wzxRN5heeM0ERrcQggebu p3JVb9Sf8v5SOd4fqfyMBCc06/aGuLhPo3TqK+hCVf4lxt81BEN0PxKJyLSgLL8BHG WDeo/YpyEEGC20hF/v69tBjkHwhTRMFp1f32P+bg= Date: Mon, 30 Jan 2023 16:14:25 -0800 To: mm-commits@vger.kernel.org, jane.chu@oracle.com, fengwei.yin@intel.com, david@redhat.com, vishal.moola@gmail.com, akpm@linux-foundation.org From: Andrew Morton Subject: + mm-add-folio_estimated_sharers.patch added to mm-unstable branch Message-Id: <20230131001426.86B43C433EF@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: mm: add folio_estimated_sharers() has been added to the -mm mm-unstable branch. Its filename is mm-add-folio_estimated_sharers.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-add-folio_estimated_sharers.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: "Vishal Moola (Oracle)" Subject: mm: add folio_estimated_sharers() Date: Mon, 30 Jan 2023 12:18:28 -0800 Patch series "Convert various mempolicy.c functions to use folios", v4. This patch series converts migrate_page_add() and queue_pages_required() to migrate_folio_add() and queue_page_required(). It also converts the callers of the functions to use folios as well, and introduces a helper function to estimate the number of sharers of a folio. This patch (of 6): folio_estimated_sharers() takes in a folio and returns the precise number of times the first subpage of the folio is mapped. This function aims to provide an estimate for the number of sharers of a folio. This is necessary for folio conversions where we care about the number of processes that share a folio, but don't necessarily want to check every single page within that folio. This is in contrast to folio_mapcount() which calculates the total number of the times a folio and all its subpages are mapped. Link: https://lkml.kernel.org/r/20230130201833.27042-1-vishal.moola@gmail.com Link: https://lkml.kernel.org/r/20230130201833.27042-2-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) Cc: David Hildenbrand Cc: Jane Chu Cc: "Yin, Fengwei" Signed-off-by: Andrew Morton --- --- a/include/linux/mm.h~mm-add-folio_estimated_sharers +++ a/include/linux/mm.h @@ -1911,6 +1911,24 @@ static inline size_t folio_size(struct f return PAGE_SIZE << folio_order(folio); } +/** + * folio_estimated_sharers - Estimate the number of sharers of a folio. + * @folio: The folio. + * + * folio_estimated_sharers() aims to serve as a function to efficiently + * estimate the number of processes sharing a folio. This is done by + * looking at the precise mapcount of the first subpage in the folio, and + * assuming the other subpages are the same. This may not be true for large + * folios. If you want exact mapcounts for exact calculations, look at + * page_mapcount() or folio_total_mapcount(). + * + * Return: The estimated number of processes sharing a folio. + */ +static inline int folio_estimated_sharers(struct folio *folio) +{ + return page_mapcount(folio_page(folio, 0)); +} + #ifndef HAVE_ARCH_MAKE_PAGE_ACCESSIBLE static inline int arch_make_page_accessible(struct page *page) { _ Patches currently in -mm which might be from vishal.moola@gmail.com are mm-khugepaged-introduce-release_pte_folio-to-replace-release_pte_page.patch mm-khugepaged-convert-release_pte_pages-to-use-folios.patch pagemap-add-filemap_grab_folio.patch filemap-added-filemap_get_folios_tag.patch filemap-convert-__filemap_fdatawait_range-to-use-filemap_get_folios_tag.patch page-writeback-convert-write_cache_pages-to-use-filemap_get_folios_tag.patch afs-convert-afs_writepages_region-to-use-filemap_get_folios_tag.patch btrfs-convert-btree_write_cache_pages-to-use-filemap_get_folio_tag.patch btrfs-convert-extent_write_cache_pages-to-use-filemap_get_folios_tag.patch ceph-convert-ceph_writepages_start-to-use-filemap_get_folios_tag.patch cifs-convert-wdata_alloc_and_fillpages-to-use-filemap_get_folios_tag.patch ext4-convert-mpage_prepare_extent_to_map-to-use-filemap_get_folios_tag.patch f2fs-convert-f2fs_fsync_node_pages-to-use-filemap_get_folios_tag.patch f2fs-convert-f2fs_flush_inline_data-to-use-filemap_get_folios_tag.patch f2fs-convert-f2fs_sync_node_pages-to-use-filemap_get_folios_tag.patch f2fs-convert-f2fs_write_cache_pages-to-use-filemap_get_folios_tag.patch f2fs-convert-last_fsync_dnode-to-use-filemap_get_folios_tag.patch f2fs-convert-f2fs_sync_meta_pages-to-use-filemap_get_folios_tag.patch gfs2-convert-gfs2_write_cache_jdata-to-use-filemap_get_folios_tag.patch nilfs2-convert-nilfs_lookup_dirty_data_buffers-to-use-filemap_get_folios_tag.patch nilfs2-convert-nilfs_lookup_dirty_node_buffers-to-use-filemap_get_folios_tag.patch nilfs2-convert-nilfs_btree_lookup_dirty_buffers-to-use-filemap_get_folios_tag.patch nilfs2-convert-nilfs_copy_dirty_pages-to-use-filemap_get_folios_tag.patch nilfs2-convert-nilfs_clear_dirty_pages-to-use-filemap_get_folios_tag.patch filemap-remove-find_get_pages_range_tag.patch mm-add-folio_estimated_sharers.patch mm-mempolicy-convert-queue_pages_pmd-to-queue_folios_pmd.patch mm-mempolicy-convert-queue_pages_pte_range-to-queue_folios_pte_range.patch mm-mempolicy-convert-queue_pages_hugetlb-to-queue_folios_hugetlb.patch mm-mempolicy-convert-queue_pages_required-to-queue_folio_required.patch mm-mempolicy-convert-migrate_page_add-to-migrate_folio_add.patch