The patch titled Subject: mm/compaction: skip page block marked skip in isolate_migratepages_block has been added to the -mm mm-unstable branch. Its filename is mm-compaction-skip-page-block-marked-skip-in-isolate_migratepages_block.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-compaction-skip-page-block-marked-skip-in-isolate_migratepages_block.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: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx> Subject: mm/compaction: skip page block marked skip in isolate_migratepages_block Date: Fri, 4 Aug 2023 19:04:49 +0800 Move migrate_pfn to page block end when block is marked skip to avoid unnecessary scan retry of that block from upper caller. For example, compact_zone may wrongly rescan skip page block with finish_pageblock set as following: 1. cc->migrate point to the start of page block 2. compact_zone record last_migrated_pfn to cc->migrate 3. compact_zone->isolate_migratepages->isolate_migratepages_block tries to scan the block. The low_pfn maybe moved forward to middle of block because of free pages at beginning of block. 4. we find first lru page could be isolated but block was exclusive marked skip. 5. abort isolate_migratepages_block and make cc->migrate_pfn point to found lru page at middle of block. 6. compact_zone find cc->migrate_pfn and last_migrated_pfn are in the same block and wrongly rescan the block with finish_pageblock set. Link: https://lkml.kernel.org/r/20230804110454.2935878-4-shikemeng@xxxxxxxxxxxxxxx Signed-off-by: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx> Reviewed-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/compaction.c | 1 + 1 file changed, 1 insertion(+) --- a/mm/compaction.c~mm-compaction-skip-page-block-marked-skip-in-isolate_migratepages_block +++ a/mm/compaction.c @@ -1141,6 +1141,7 @@ isolate_migratepages_block(struct compac skip_updated = true; if (test_and_set_skip(cc, valid_page) && !cc->finish_pageblock) { + low_pfn = end_pfn; goto isolate_abort; } } _ Patches currently in -mm which might be from shikemeng@xxxxxxxxxxxxxxx are mm-correct-stale-comment-of-function-check_pte.patch mm-page_table_check-remove-unused-parameters-in-page_table_check_clear.patch mm-page_table_check-remove-unused-parameters-in-page_table_check_set.patch mm-page_table_check-remove-unused-parameter-in-page_table_check_pte_clear.patch mm-page_table_check-remove-unused-parameter-in-page_table_check_pmd_clear.patch mm-page_table_check-remove-unused-parameter-in-page_table_check_pud_clear.patch mm-page_table_check-remove-unused-parameter-in-page_table_check_pte_set.patch mm-page_table_check-remove-unused-parameter-in-page_table_check_pmd_set.patch mm-page_table_check-remove-unused-parameter-in-page_table_check_pud_set.patch mm-page_ext-remove-unused-return-value-of-offline_page_ext.patch mm-page_ext-remove-rollback-for-untouched-mem_section-in-online_page_ext.patch mm-page_ext-move-functions-around-for-minor-cleanups-to-page_ext.patch mm-page_ext-add-common-function-to-get-client-data-from-page_ext.patch mm-page_ext-use-page_ext_data-helper-in-page_table_check.patch mm-page_ext-use-page_ext_data-helper-in-page_owner.patch mm-rmap-correct-stale-comment-of-rmap_walk_anon-and-rmap_walk_file.patch mm-page_poison-remove-unused-page_exth-from-page_poison.patch mm-vmstat-remove-unused-page_exth-from-vmstat.patch mm-page_ext-move-page_ext_operations-definition-under-config_page_extension.patch mm-compaction-set-compact_cached_free_pfn-correctly-in-update_pageblock_skip.patch mm-compaction-remove-unnecessary-cursor-page-in-isolate_freepages_block.patch mm-compaction-remove-unnecessary-else-continue-at-end-of-loop-in-isolate_freepages_block.patch mm-compaction-avoid-missing-last-page-block-in-section-after-skip-offline-sections.patch mm-compaction-correct-last_migrated_pfn-update-in-compact_zone.patch mm-compaction-skip-page-block-marked-skip-in-isolate_migratepages_block.patch mm-compaction-correct-comment-of-fast_find_migrateblock-in-isolate_migratepages.patch mm-compaction-correct-comment-of-cached-migrate-pfn-update.patch mm-compaction-correct-comment-to-complete-migration-failure.patch mm-compaction-remove-unnecessary-return-for-void-function.patch mm-compaction-only-set-skip-flag-if-cc-no_set_skip_hint-is-false.patch