The patch titled mm: compaction: various fixes to the patch 'Memory compaction core' has been removed from the -mm tree. Its filename was mm-compaction-memory-compaction-core-fix.patch This patch was dropped because an updated version will be merged The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: mm: compaction: various fixes to the patch 'Memory compaction core' From: Mel Gorman <mel@xxxxxxxxx> o Use unsigned long instead of int for page counters o Simplify logic in isolate_freepages_block() and isolate_migratepages() o Optimise isolate_freepages_block to use a cursor o Use bool instead of int for true/false o Clarify some comments o Improve control flow in isolate_migratepages() o Add newlines for clarity o Simply loop in compact_zones Signed-off-by: Mel Gorman <mel@xxxxxxxxx> Cc: Rik van Riel <riel@xxxxxxxxxx> Cc: Minchan Kim <minchan.kim@xxxxxxxxx> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> Cc: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> Cc: Christoph Lameter <cl@xxxxxxxxxxxxxxxxxxxx> Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/compaction.c | 81 ++++++++++++++++++++++++++-------------------- mm/page_alloc.c | 2 - 2 files changed, 47 insertions(+), 36 deletions(-) diff -puN mm/Kconfig~mm-compaction-memory-compaction-core-fix mm/Kconfig diff -puN mm/compaction.c~mm-compaction-memory-compaction-core-fix mm/compaction.c --- a/mm/compaction.c~mm-compaction-memory-compaction-core-fix +++ a/mm/compaction.c @@ -36,10 +36,10 @@ struct compact_control { struct zone *zone; }; -static int release_freepages(struct list_head *freelist) +static unsigned long release_freepages(struct list_head *freelist) { struct page *page, *next; - int count = 0; + unsigned long count = 0; list_for_each_entry_safe(page, next, freelist, lru) { list_del(&page->lru); @@ -51,28 +51,33 @@ static int release_freepages(struct list } /* Isolate free pages onto a private freelist. Must hold zone->lock */ -static int isolate_freepages_block(struct zone *zone, +static unsigned long isolate_freepages_block(struct zone *zone, unsigned long blockpfn, struct list_head *freelist) { unsigned long zone_end_pfn, end_pfn; int total_isolated = 0; + struct page *cursor; /* Get the last PFN we should scan for free pages at */ zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages; - end_pfn = blockpfn + pageblock_nr_pages; - if (end_pfn > zone_end_pfn) - end_pfn = zone_end_pfn; + end_pfn = min(blockpfn + pageblock_nr_pages, zone_end_pfn); - /* Isolate free pages. This assumes the block is valid */ + /* Find the first usable PFN in the block to initialse page cursor */ for (; blockpfn < end_pfn; blockpfn++) { - struct page *page; + if (pfn_valid_within(blockpfn)) + break; + } + cursor = pfn_to_page(blockpfn); + + /* Isolate free pages. This assumes the block is valid */ + for (; blockpfn < end_pfn; blockpfn++, cursor++) { int isolated, i; + struct page *page = cursor; if (!pfn_valid_within(blockpfn)) continue; - page = pfn_to_page(blockpfn); if (!PageBuddy(page)) continue; @@ -85,38 +90,40 @@ static int isolate_freepages_block(struc } /* If a page was split, advance to the end of it */ - if (isolated) + if (isolated) { blockpfn += isolated - 1; + cursor += isolated - 1; + } } return total_isolated; } -/* Returns 1 if the page is within a block suitable for migration to */ -static int suitable_migration_target(struct page *page) +/* Returns true if the page is within a block suitable for migration to */ +static bool suitable_migration_target(struct page *page) { int migratetype = get_pageblock_migratetype(page); /* Don't interfere with memory hot-remove or the min_free_kbytes blocks */ if (migratetype == MIGRATE_ISOLATE || migratetype == MIGRATE_RESERVE) - return 0; + return false; /* If the page is a large free page, then allow migration */ if (PageBuddy(page) && page_order(page) >= pageblock_order) - return 1; + return true; /* If the block is MIGRATE_MOVABLE, allow migration */ if (migratetype == MIGRATE_MOVABLE) - return 1; + return true; /* Otherwise skip the block */ - return 0; + return false; } /* * Based on information in the current compact_control, find blocks - * suitable for isolating free pages from + * suitable for isolating free pages from and then isolate them. */ static void isolate_freepages(struct zone *zone, struct compact_control *cc) @@ -139,7 +146,7 @@ static void isolate_freepages(struct zon spin_lock_irqsave(&zone->lock, flags); for (; pfn > low_pfn && cc->nr_migratepages > nr_freepages; pfn -= pageblock_nr_pages) { - int isolated; + unsigned long isolated; if (!pfn_valid(pfn)) continue; @@ -195,7 +202,7 @@ static void acct_isolated(struct zone *z } /* Similar to reclaim, but different enough that they don't share logic */ -static int too_many_isolated(struct zone *zone) +static bool too_many_isolated(struct zone *zone) { unsigned long inactive, isolated; @@ -216,16 +223,12 @@ static unsigned long isolate_migratepage struct compact_control *cc) { unsigned long low_pfn, end_pfn; - struct list_head *migratelist; - - low_pfn = cc->migrate_pfn; - migratelist = &cc->migratepages; + struct list_head *migratelist = &cc->migratepages; /* Do not scan outside zone boundaries */ - if (low_pfn < zone->zone_start_pfn) - low_pfn = zone->zone_start_pfn; + low_pfn = max(cc->migrate_pfn, zone->zone_start_pfn); - /* Setup to scan one block but not past where we are migrating to */ + /* Only scan within a pageblock boundary */ end_pfn = ALIGN(low_pfn + pageblock_nr_pages, pageblock_nr_pages); /* Do not cross the free scanner or scan within a memory hole */ @@ -234,7 +237,11 @@ static unsigned long isolate_migratepage return 0; } - /* Do not isolate the world */ + /* + * Ensure that there are not too many pages isolated from the LRU + * list by either parallel reclaimers or compaction. If there are, + * delay for some time until fewer pages are isolated + */ while (unlikely(too_many_isolated(zone))) { congestion_wait(BLK_RW_ASYNC, HZ/10); @@ -257,12 +264,14 @@ static unsigned long isolate_migratepage } /* Try isolate the page */ - if (__isolate_lru_page(page, ISOLATE_BOTH, 0) == 0) { - del_page_from_lru_list(zone, page, page_lru(page)); - list_add(&page->lru, migratelist); - mem_cgroup_del_lru(page); - cc->nr_migratepages++; - } + if (__isolate_lru_page(page, ISOLATE_BOTH, 0) != 0) + continue; + + /* Successfully isolated */ + del_page_from_lru_list(zone, page, page_lru(page)); + list_add(&page->lru, migratelist); + mem_cgroup_del_lru(page); + cc->nr_migratepages++; /* Avoid isolating too much */ if (cc->nr_migratepages == COMPACT_CLUSTER_MAX) @@ -313,6 +322,7 @@ static void update_nr_listpages(struct c int nr_migratepages = 0; int nr_freepages = 0; struct page *page; + list_for_each_entry(page, &cc->migratepages, lru) nr_migratepages++; list_for_each_entry(page, &cc->freepages, lru) @@ -337,7 +347,7 @@ static inline int compact_finished(struc static int compact_zone(struct zone *zone, struct compact_control *cc) { - int ret = COMPACT_INCOMPLETE; + int ret; /* Setup to move all movable pages to the end of the zone */ cc->migrate_pfn = zone->zone_start_pfn; @@ -346,8 +356,9 @@ static int compact_zone(struct zone *zon migrate_prep(); - for (; ret == COMPACT_INCOMPLETE; ret = compact_finished(zone, cc)) { + while ((ret = compact_finished(zone, cc)) == COMPACT_INCOMPLETE) { unsigned long nr_migrate, nr_remaining; + if (!isolate_migratepages(zone, cc)) continue; diff -puN mm/page_alloc.c~mm-compaction-memory-compaction-core-fix mm/page_alloc.c --- a/mm/page_alloc.c~mm-compaction-memory-compaction-core-fix +++ a/mm/page_alloc.c @@ -1222,7 +1222,7 @@ int split_free_page(struct page *page) zone = page_zone(page); order = page_order(page); - /* Obey watermarks or the system could deadlock */ + /* Obey watermarks as if the page was being allocated */ watermark = low_wmark_pages(zone) + (1 << order); if (!zone_watermark_ok(zone, 0, watermark, 0, 0)) return 0; _ Patches currently in -mm which might be from mel@xxxxxxxxx are linux-next.patch hugetlb-fix-infinite-loop-in-get_futex_key-when-backed-by-huge-pages.patch hugetlb-fix-infinite-loop-in-get_futex_key-when-backed-by-huge-pages-fix.patch hugetlbfs-kill-applications-that-use-map_noreserve-with-sigbus-instead-of-oom-killer.patch page-allocator-reduce-fragmentation-in-buddy-allocator-by-adding-buddies-that-are-merging-to-the-tail-of-the-free-lists.patch mempolicy-remove-redundant-code.patch mm-default-to-node-zonelist-ordering-when-nodes-have-only-lowmem.patch mm-compaction-memory-compaction-core-fix.patch mm-compaction-memory-compaction-core-fix-page-buddy-can-go-away-before-reading-page_order-while-isolating-pages-for-migration.patch mm-compaction-memory-compaction-core-map-free-pages-in-the-address-space-after-they-get-split-for-compaction.patch mm-compaction-add-proc-trigger-for-memory-compaction.patch mm-compaction-add-proc-trigger-for-memory-compaction-fix.patch mm-compaction-add-proc-trigger-for-memory-compaction-fix-fix.patch mm-compaction-add-sys-trigger-for-per-node-memory-compaction.patch mm-compaction-direct-compact-when-a-high-order-allocation-fails.patch mm-compaction-direct-compact-when-a-high-order-allocation-fails-reject-fix.patch mm-compaction-add-a-tunable-that-decides-when-memory-should-be-compacted-and-when-it-should-be-reclaimed.patch vmstat-fix-build-errors-when-proc_fs-is-disabled.patch vmstat-fix-build-errors-when-proc_fs-is-disabled-checkpatch-fixes.patch mm-migration-allow-the-migration-of-pageswapcache-pages.patch mm-migration-allow-the-migration-of-pageswapcache-pages-fix.patch mm-compaction-do-not-display-compaction-related-stats-when-config_compaction.patch mm-compaction-do-not-display-compaction-related-stats-when-config_compaction-fix.patch mm-compaction-do-not-display-compaction-related-stats-when-config_compaction-fix-fix-2.patch mm-compaction-do-not-display-compaction-related-stats-when-config_compaction-fix-fix-2-do-not-compact-twice.patch mm-compaction-do-not-display-compaction-related-stats-when-config_co-mpaction-reject-fixpatch-added-to-mm-tree.patch mm-introduce-free_pages_prepare.patch mm-introduce-free_pages_prepare-fix.patch delay-accounting-re-implement-c-for-getdelaysc-to-report-information-on-a-target-command.patch delay-accounting-re-implement-c-for-getdelaysc-to-report-information-on-a-target-command-checkpatch-fixes.patch numa-add-generic-percpu-var-numa_node_id-implementation.patch numa-x86_64-use-generic-percpu-var-numa_node_id-implementation.patch numa-ia64-use-generic-percpu-var-numa_node_id-implementation.patch numa-introduce-numa_mem_id-effective-local-memory-node-id.patch numa-ia64-support-numa_mem_id-for-memoryless-nodes.patch numa-slab-use-numa_mem_id-for-slab-local-memory-node.patch numa-in-kernel-profiling-use-cpu_to_mem-for-per-cpu-allocations.patch numa-update-documentation-vm-numa-add-memoryless-node-info.patch add-debugging-aid-for-memory-initialisation-problems.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html