From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 43FCEB660 for ; Sun, 4 Feb 2024 07:20:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707031245; cv=none; b=aUd0+/zUU6wlVd/HZ+l78r3SZYRtVaEJySS4Ry3rI3moB/nBDxoJu9h4EhP3IZ4seMzSyHhz9nKC1+H/9nGZXgWKFYM6xfpQOMnVHFqHfrKOY28EAuhYVU1PnkCiGBVHOBny7rhthxXX2zhwdWmFfZwYafwGO9SpDk7j/aaqUYw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707031245; c=relaxed/simple; bh=yq/Tm7/p4tq2fScvScNcGcVZB46/d+z7zmrUdTyGFkI=; h=Date:To:From:Subject:Message-Id; b=olYHBHiNlJelj0eGFNu4D5Rp3zJL91ack/gpbBnLyOucB1uefkboXbTo/L2Y4PSrhF80fyJItIOfOQuOokeO2yEuuIvqf6+DWi1OpyWo++J3Eyn3d97Ph8sXhilyCxBR3obuyDrf6/F9bwU5NgjMtoxqJaI4K4ol3z4D7GDYcSE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=IeCac5Y4; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="IeCac5Y4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0DEDEC433C7; Sun, 4 Feb 2024 07:20:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1707031245; bh=yq/Tm7/p4tq2fScvScNcGcVZB46/d+z7zmrUdTyGFkI=; h=Date:To:From:Subject:From; b=IeCac5Y4CxpJoS81Rpyvlg+hZoGoyGUp8PTiEQp1M9tQdPQ74HVO4KaBt93Bu1AVG 0dLnAO4BML6NOD6UDSiOycrOwnNjDlgzoH+IhnGmKlkVIY/CxOeweFJEMm2RCBOwMU hqe63mn76ZRWtMGRebftn9biP3AW/6G1zDZ3S7Sk= Date: Sat, 03 Feb 2024 23:20:44 -0800 To: mm-commits@vger.kernel.org,yuzhao@google.com,ying.huang@intel.com,willy@infradead.org,vishal.moola@gmail.com,vbabka@suse.cz,shikemeng@huaweicloud.com,ryan.roberts@arm.com,mgorman@techsingularity.net,mcgrof@kernel.org,kirill.shutemov@linux.intel.com,hannes@cmpxchg.org,fengwei.yin@intel.com,david@redhat.com,baolin.wang@linux.alibaba.com,a.manzanares@samsung.com,ziy@nvidia.com,akpm@linux-foundation.org From: Andrew Morton Subject: + mm-compaction-enable-compacting-0-order-folios.patch added to mm-unstable branch Message-Id: <20240204072045.0DEDEC433C7@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: mm/compaction: enable compacting >0 order folios. has been added to the -mm mm-unstable branch. Its filename is mm-compaction-enable-compacting-0-order-folios.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-compaction-enable-compacting-0-order-folios.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: Zi Yan Subject: mm/compaction: enable compacting >0 order folios. Date: Fri, 2 Feb 2024 11:15:52 -0500 Patch series "Enable >0 order folio memory compaction", v3. This patchset enables >0 order folio memory compaction, which is one of the prerequisitions for large folio support[1]. It includes the fix[4] for V2 and is on top of mm-everything-2024-01-29-07-19. I am aware of that split free pages is necessary for folio migration in compaction, since if >0 order free pages are never split and no order-0 free page is scanned, compaction will end prematurely due to migration returns -ENOMEM. Free page split becomes a must instead of an optimization. lkp ncompare results for default LRU (-no-mglru) and CONFIG_LRU_GEN are shown at the bottom (on a 8-CPU (Intel Xeon E5-2650 v4 @ 2.20GHz) 16G VM). In sum, most of vm-scalability applications do not see performance change, and the others see ~4% to ~26% performance boost under default LRU and ~2% to ~6% performance boost under CONFIG_LRU_GEN. This patch (of 3): migrate_pages() supports >0 order folio migration and during compaction, even if compaction_alloc() cannot provide >0 order free pages, migrate_pages() can split the source page and try to migrate the base pages from the split. It can be a baseline and start point for adding support for compacting >0 order folios. Link: https://lkml.kernel.org/r/20240202161554.565023-1-zi.yan@sent.com Link: https://lkml.kernel.org/r/20240202161554.565023-2-zi.yan@sent.com Signed-off-by: Zi Yan Suggested-by: Huang Ying Cc: Adam Manzanares Cc: Baolin Wang Cc: David Hildenbrand Cc: Johannes Weiner Cc: Kemeng Shi Cc: Kirill A. Shutemov Cc: Luis Chamberlain Cc: Matthew Wilcox (Oracle) Cc: Mel Gorman Cc: Ryan Roberts Cc: Vishal Moola (Oracle) Cc: Vlastimil Babka Cc: Yin Fengwei Cc: Yu Zhao Signed-off-by: Andrew Morton --- mm/compaction.c | 43 +++++++++++++++++++++++++++++++++++-------- 1 file changed, 35 insertions(+), 8 deletions(-) --- a/mm/compaction.c~mm-compaction-enable-compacting-0-order-folios +++ a/mm/compaction.c @@ -816,6 +816,21 @@ static bool too_many_isolated(struct com return too_many; } +/* + * 1. if the page order is larger than or equal to target_order (i.e., + * cc->order and when it is not -1 for global compaction), skip it since + * target_order already indicates no free page with larger than target_order + * exists and later migrating it will most likely fail; + * + * 2. compacting > pageblock_order pages does not improve memory fragmentation, + * skip them; + */ +static bool skip_isolation_on_order(int order, int target_order) +{ + return (target_order != -1 && order >= target_order) || + order >= pageblock_order; +} + /** * isolate_migratepages_block() - isolate all migrate-able pages within * a single pageblock @@ -1010,7 +1025,7 @@ isolate_migratepages_block(struct compac /* * Regardless of being on LRU, compound pages such as THP and * hugetlbfs are not to be compacted unless we are attempting - * an allocation much larger than the huge page size (eg CMA). + * an allocation larger than the compound page size. * We can potentially save a lot of iterations if we skip them * at once. The check is racy, but we can consider only valid * values and the only danger is skipping too much. @@ -1018,11 +1033,18 @@ isolate_migratepages_block(struct compac if (PageCompound(page) && !cc->alloc_contig) { const unsigned int order = compound_order(page); - if (likely(order <= MAX_PAGE_ORDER)) { - low_pfn += (1UL << order) - 1; - nr_scanned += (1UL << order) - 1; + /* + * Skip based on page order and compaction target order + * and skip hugetlbfs pages. + */ + if (skip_isolation_on_order(order, cc->order) || + PageHuge(page)) { + if (order <= MAX_PAGE_ORDER) { + low_pfn += (1UL << order) - 1; + nr_scanned += (1UL << order) - 1; + } + goto isolate_fail; } - goto isolate_fail; } /* @@ -1165,10 +1187,11 @@ isolate_migratepages_block(struct compac } /* - * folio become large since the non-locked check, - * and it's on LRU. + * Check LRU folio order under the lock */ - if (unlikely(folio_test_large(folio) && !cc->alloc_contig)) { + if (unlikely(skip_isolation_on_order(folio_order(folio), + cc->order) && + !cc->alloc_contig)) { low_pfn += folio_nr_pages(folio) - 1; nr_scanned += folio_nr_pages(folio) - 1; folio_set_lru(folio); @@ -1786,6 +1809,10 @@ static struct folio *compaction_alloc(st struct compact_control *cc = (struct compact_control *)data; struct folio *dst; + /* this makes migrate_pages() split the source page and retry */ + if (folio_test_large(src) > 0) + return NULL; + if (list_empty(&cc->freepages)) { isolate_freepages(cc); _ Patches currently in -mm which might be from ziy@nvidia.com are mm-compaction-enable-compacting-0-order-folios.patch mm-compaction-add-support-for-0-order-folio-memory-compaction.patch mm-compaction-optimize-0-order-folio-compaction-with-free-page-split.patch