The patch titled Subject: mm: compaction: iron out isolate_freepages_block() and isolate_freepages_range() has been removed from the -mm tree. Its filename was mm-compaction-acquire-the-zone-lock-as-late-as-possible-fix-2.patch This patch was dropped because it was folded into mm-compaction-acquire-the-zone-lock-as-late-as-possible.patch ------------------------------------------------------ From: Mel Gorman <mgorman@xxxxxxx> Subject: mm: compaction: iron out isolate_freepages_block() and isolate_freepages_range() Andrew pointed out that isolate_freepages_block() is "straggly" and isolate_freepages_range() is making assumptions on how compact_control is used which is delicate. This patch straightens isolate_freepages_block() and makes it fly straight and initialses compact_control to zeros in isolate_freepages_range(). The code should be easier to follow and is functionally equivalent. The CMA failure path is now a little more expensive but that is a marginal corner-case. Signed-off-by: Mel Gorman <mgorman@xxxxxxx> Cc: Rik van Riel <riel@xxxxxxxxxx> Cc: Richard Davies <richard@xxxxxxxxxxxx> Cc: Shaohua Li <shli@xxxxxxxxxx> Cc: Avi Kivity <avi@xxxxxxxxxx> Cc: Rafael Aquini <aquini@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/compaction.c | 48 +++++++++++++++++++++------------------------- 1 file changed, 22 insertions(+), 26 deletions(-) diff -puN mm/compaction.c~mm-compaction-acquire-the-zone-lock-as-late-as-possible-fix-2 mm/compaction.c --- a/mm/compaction.c~mm-compaction-acquire-the-zone-lock-as-late-as-possible-fix-2 +++ a/mm/compaction.c @@ -96,7 +96,6 @@ static inline bool compact_trylock_irqsa /* 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 */ @@ -188,21 +187,20 @@ static unsigned long isolate_freepages_b cursor = pfn_to_page(blockpfn); - /* Isolate free pages. This assumes the block is valid */ + /* Isolate free pages. */ for (; blockpfn < end_pfn; blockpfn++, cursor++) { int isolated, i; struct page *page = cursor; - if (!pfn_valid_within(blockpfn)) - goto strict_check; nr_scanned++; - + if (!pfn_valid_within(blockpfn)) + continue; if (!PageBuddy(page)) - goto strict_check; + continue; /* - * The zone lock must be held to isolate freepages. This - * unfortunately this is a very coarse lock and can be + * The zone lock must be held to isolate freepages. + * Unfortunately this is a very coarse lock and can be * heavily contended if there are parallel allocations * or parallel compactions. For async compaction do not * spin on the lock and we acquire the lock as late as @@ -219,12 +217,12 @@ static unsigned long isolate_freepages_b /* Recheck this is a buddy page under lock */ if (!PageBuddy(page)) - goto strict_check; + continue; /* Found a free page, break it into order-0 pages */ isolated = split_free_page(page); if (!isolated && strict) - goto strict_check; + break; total_isolated += isolated; for (i = 0; i < isolated; i++) { list_add(&page->lru, freelist); @@ -236,20 +234,18 @@ static unsigned long isolate_freepages_b blockpfn += isolated - 1; cursor += isolated - 1; } - - continue; - -strict_check: - /* Abort isolation if the caller requested strict isolation */ - if (strict) { - total_isolated = 0; - goto out; - } } trace_mm_compaction_isolate_freepages(nr_scanned, total_isolated); -out: + /* + * If strict isolation is requested by CMA then check that all the + * pages scanned were isolated. If there were any failures, 0 is + * returned and CMA will fail. + */ + if (strict && nr_scanned != total_isolated) + total_isolated = 0; + if (locked) spin_unlock_irqrestore(&cc->zone->lock, flags); @@ -275,14 +271,14 @@ isolate_freepages_range(unsigned long st unsigned long isolated, pfn, block_end_pfn; struct zone *zone = NULL; LIST_HEAD(freelist); - struct compact_control cc; - - if (pfn_valid(start_pfn)) - zone = page_zone(pfn_to_page(start_pfn)); /* cc needed for isolate_freepages_block to acquire zone->lock */ - cc.zone = zone; - cc.sync = true; + struct compact_control cc = { + .sync = true, + }; + + if (pfn_valid(start_pfn)) + cc.zone = zone = page_zone(pfn_to_page(start_pfn)); for (pfn = start_pfn; pfn < end_pfn; pfn += isolated) { if (!pfn_valid(pfn) || zone != page_zone(pfn_to_page(pfn))) _ Patches currently in -mm which might be from mgorman@xxxxxxx are mm-remove-__gfp_no_kswapd.patch mm-compaction-update-comment-in-try_to_compact_pages.patch mm-vmscan-scale-number-of-pages-reclaimed-by-reclaim-compaction-based-on-failures.patch mm-compaction-capture-a-suitable-high-order-page-immediately-when-it-is-made-available.patch revert-mm-mempolicy-let-vma_merge-and-vma_split-handle-vma-vm_policy-linkages.patch mempolicy-remove-mempolicy-sharing.patch mempolicy-fix-a-race-in-shared_policy_replace.patch mempolicy-fix-refcount-leak-in-mpol_set_shared_policy.patch mempolicy-fix-a-memory-corruption-by-refcount-imbalance-in-alloc_pages_vma.patch mm-cma-discard-clean-pages-during-contiguous-allocation-instead-of-migration.patch mm-fix-tracing-in-free_pcppages_bulk.patch cma-fix-counting-of-isolated-pages.patch cma-count-free-cma-pages.patch cma-fix-watermark-checking.patch mm-page_alloc-use-get_freepage_migratetype-instead-of-page_private.patch mm-remain-migratetype-in-freed-page.patch memory-hotplug-bug-fix-race-between-isolation-and-allocation.patch memory-hotplug-fix-pages-missed-by-race-rather-than-failing.patch mm-compaction-abort-compaction-loop-if-lock-is-contended-or-run-too-long.patch mm-compaction-move-fatal-signal-check-out-of-compact_checklock_irqsave.patch mm-compaction-update-try_to_compact_pageskerneldoc-comment.patch mm-compaction-acquire-the-zone-lru_lock-as-late-as-possible.patch mm-compaction-acquire-the-zone-lock-as-late-as-possible.patch mm-compaction-acquire-the-zone-lock-as-late-as-possible-fix-3.patch revert-mm-have-order-0-compaction-start-off-where-it-left.patch mm-compaction-cache-if-a-pageblock-was-scanned-and-no-pages-were-isolated.patch mm-compaction-cache-if-a-pageblock-was-scanned-and-no-pages-were-isolated-fix.patch mm-compaction-cache-if-a-pageblock-was-scanned-and-no-pages-were-isolated-fix2.patch mm-compaction-cache-if-a-pageblock-was-scanned-and-no-pages-were-isolated-fix3.patch mm-compaction-restart-compaction-from-near-where-it-left-off.patch mm-compaction-restart-compaction-from-near-where-it-left-off-fix.patch mm-compaction-clear-pg_migrate_skip-based-on-compaction-and-reclaim-activity.patch mm-numa-reclaim-from-all-nodes-within-reclaim-distance.patch mm-numa-reclaim-from-all-nodes-within-reclaim-distance-fix.patch mm-numa-reclaim-from-all-nodes-within-reclaim-distance-fix-fix.patch mm-thp-fix-pmd_present-for-split_huge_page-and-prot_none-with-thp.patch mm-revert-0def08e3-mm-mempolicyc-check-return-code-of-check_range.patch mm-revert-0def08e3-mm-mempolicyc-check-return-code-of-check_range-fix.patch cma-migrate-mlocked-pages.patch cma-migrate-mlocked-pages-fix.patch cma-decrease-ccnr_migratepages-after-reclaiming-pagelist.patch make-gfp_notrack-definition-unconditional.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