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 B0193C433EF for ; Mon, 9 May 2022 21:17:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229476AbiEIVVj (ORCPT ); Mon, 9 May 2022 17:21:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41612 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230117AbiEIVV1 (ORCPT ); Mon, 9 May 2022 17:21:27 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C855021607A for ; Mon, 9 May 2022 14:17:32 -0700 (PDT) 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 661C7616FE for ; Mon, 9 May 2022 21:17:32 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BEAC8C385BB; Mon, 9 May 2022 21:17:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1652131051; bh=p9UgZjKgmwOi5tgeW59tgN/BDusV8J2DiV2nM9olkdg=; h=Date:To:From:Subject:From; b=DHqT1G1I4Gpcf8uqYMpUL8LEQ1YCK8E9ejU4Dd0mc2YTWkn9V7Ic4T0zYoubMb6+V nYVcva8Nwd35LsIKEoucVICV+zsgvy9Dv/lyhbFhZvqhRkV+JK7kraTPUjZBQ6BLuS 12lcSuj/DEO5o4ZNSKne7dvUQPV5O73oWYvy8cC8= Date: Mon, 09 May 2022 14:17:31 -0700 To: mm-commits@vger.kernel.org, willy@infradead.org, vbabka@suse.cz, surenb@google.com, peterx@redhat.com, neilb@suse.de, naoya.horiguchi@nec.com, dhowells@redhat.com, david@redhat.com, apopple@nvidia.com, linmiaohe@huawei.com, akpm@linux-foundation.org From: Andrew Morton Subject: + mm-swap-fix-comment-about-swap-extent.patch added to mm-unstable branch Message-Id: <20220509211731.BEAC8C385BB@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/swap: fix comment about swap extent has been added to the -mm mm-unstable branch. Its filename is mm-swap-fix-comment-about-swap-extent.patch This patch should soon 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: Miaohe Lin Subject: mm/swap: fix comment about swap extent Since commit 4efaceb1c5f8 ("mm, swap: use rbtree for swap_extent"), rbtree is used for swap extent. Also curr_swap_extent is removed at that time. Update the corresponding comment. Link: https://lkml.kernel.org/r/20220509131416.17553-16-linmiaohe@huawei.com Signed-off-by: Miaohe Lin Cc: Alistair Popple Cc: David Hildenbrand Cc: David Howells Cc: Matthew Wilcox Cc: Naoya Horiguchi Cc: NeilBrown Cc: Peter Xu Cc: Suren Baghdasaryan Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- include/linux/swap.h | 4 ++-- mm/swapfile.c | 15 ++++++--------- 2 files changed, 8 insertions(+), 11 deletions(-) --- a/include/linux/swap.h~mm-swap-fix-comment-about-swap-extent +++ a/include/linux/swap.h @@ -173,8 +173,8 @@ struct zone; /* * A swap extent maps a range of a swapfile's PAGE_SIZE pages onto a range of - * disk blocks. A list of swap extents maps the entire swapfile. (Where the - * term `swapfile' refers to either a blockdevice or an IS_REG file. Apart + * disk blocks. A rbtree of swap extents maps the entire swapfile (Where the + * term `swapfile' refers to either a blockdevice or an IS_REG file). Apart * from setup, they're handled identically. * * We always assume that blocks are of size PAGE_SIZE. --- a/mm/swapfile.c~mm-swap-fix-comment-about-swap-extent +++ a/mm/swapfile.c @@ -2224,8 +2224,8 @@ EXPORT_SYMBOL_GPL(add_swap_extent); /* * A `swap extent' is a simple thing which maps a contiguous range of pages - * onto a contiguous range of disk blocks. An ordered list of swap extents - * is built at swapon time and is then used at swap_writepage/swap_readpage + * onto a contiguous range of disk blocks. A rbtree of swap extents is + * built at swapon time and is then used at swap_writepage/swap_readpage * time for locating where on disk a page belongs. * * If the swapfile is an S_ISBLK block device, a single extent is installed. @@ -2233,12 +2233,12 @@ EXPORT_SYMBOL_GPL(add_swap_extent); * swap files identically. * * Whether the swapdev is an S_ISREG file or an S_ISBLK blockdev, the swap - * extent list operates in PAGE_SIZE disk blocks. Both S_ISREG and S_ISBLK + * extent rbtree operates in PAGE_SIZE disk blocks. Both S_ISREG and S_ISBLK * swapfiles are handled *identically* after swapon time. * * For S_ISREG swapfiles, setup_swap_extents() will walk all the file's blocks - * and will parse them into an ordered extent list, in PAGE_SIZE chunks. If - * some stray blocks are found which do not fall within the PAGE_SIZE alignment + * and will parse them into a rbtree, in PAGE_SIZE chunks. If some stray + * blocks are found which do not fall within the PAGE_SIZE alignment * requirements, they are simply tossed out - we will never use those blocks * for swapping. * @@ -2247,10 +2247,7 @@ EXPORT_SYMBOL_GPL(add_swap_extent); * * The amount of disk space which a single swap extent represents varies. * Typically it is in the 1-4 megabyte range. So we can have hundreds of - * extents in the list. To avoid much list walking, we cache the previous - * search location in `curr_swap_extent', and start new searches from there. - * This is extremely effective. The average number of iterations in - * map_swap_page() has been measured at about 0.3 per page. - akpm. + * extents in the rbtree. - akpm. */ static int setup_swap_extents(struct swap_info_struct *sis, sector_t *span) { _ Patches currently in -mm which might be from linmiaohe@huawei.com are mm-swapfile-unuse_pte-can-map-random-data-if-swap-read-fails.patch mm-swapfile-fix-lost-swap-bits-in-unuse_pte.patch mm-madvise-free-hwpoison-and-swapin-error-entry-in-madvise_free_pte_range.patch mm-migration-reduce-the-rcu-lock-duration.patch mm-migration-remove-unneeded-lock-page-and-pagemovable-check.patch mm-migration-return-errno-when-isolate_huge_page-failed.patch mm-migration-fix-potential-pte_unmap-on-an-not-mapped-pte.patch mm-vmscan-take-min_slab_pages-into-account-when-try-to-call-shrink_node.patch mm-vmscan-add-a-comment-about-madv_free-pages-check-in-folio_check_dirty_writeback.patch mm-vmscan-introduce-helper-function-reclaim_page_list.patch mm-vmscan-take-all-base-pages-of-thp-into-account-when-race-with-speculative-reference.patch mm-vmscan-remove-obsolete-comment-in-kswapd_run.patch mm-vmscan-use-helper-folio_is_file_lru.patch mm-vmscan-use-helper-folio_is_file_lru-fix.patch mm-z3fold-fix-sheduling-while-atomic.patch mm-z3fold-fix-possible-null-pointer-dereferencing.patch mm-z3fold-remove-buggy-use-of-stale-list-for-allocation.patch mm-z3fold-throw-warning-on-failure-of-trylock_page-in-z3fold_alloc.patch revert-mm-z3foldc-allow-__gfp_highmem-in-z3fold_alloc.patch mm-z3fold-put-z3fold-page-back-into-unbuddied-list-when-reclaim-or-migration-fails.patch mm-z3fold-always-clear-page_claimed-under-z3fold-page-lock.patch mm-z3fold-fix-z3fold_reclaim_page-races-with-z3fold_free.patch mm-z3fold-fix-z3fold_page_migrate-races-with-z3fold_map.patch mm-swap-use-helper-is_swap_pte-in-swap_vma_readahead.patch mm-swap-use-helper-macro-__attr_rw.patch mm-swap-fold-__swap_info_get-into-its-sole-caller.patch mm-swap-remove-unneeded-return-value-of-free_swap_slot.patch mm-swap-print-bad-swap-offset-entry-in-get_swap_device.patch mm-swap-remove-buggy-cache-nr-check-in-refill_swap_slots_cache.patch mm-swap-remove-unneeded-p-=-null-check-in-__swap_duplicate.patch mm-swap-make-page_swapcount-and-__lru_add_drain_all.patch mm-swap-avoid-calling-swp_swap_info-when-try-to-check-swp_stable_writes.patch mm-swap-add-helper-swap_offset_available.patch mm-swap-fix-the-obsolete-comment-for-swp_type_shift.patch mm-swap-clean-up-the-comment-of-find_next_to_unuse.patch mm-swap-fix-the-comment-of-get_kernel_pages.patch mm-swap-fix-comment-about-swap-extent.patch