The patch titled
mm: compaction: do not schedule work on other CPUs for compaction
has been added to the -mm tree. Its filename is
mmcompaction-memory-compaction-core-do-not-schedule-work-on-other-cpus-for-compaction.patch
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------------------------------------------------------
Subject: mm: compaction: do not schedule work on other CPUs for compaction
From: Mel Gorman <mel@xxxxxxxxx>
Migration normally requires a call to migrate_prep() as a preparation
step. This schedules work on all CPUs for pagevecs to be drained. This
makes sense for move_pages and memory hot-remove but is unnecessary for
memory compaction.
To avoid queueing work on multiple CPUs, this patch introduces
migrate_prep_local() which drains just local pagevecs.
This patch can be either merged with
mmcompaction-memory-compaction-core.patch or placed immediately after it
to clarify why migrate_prep_local() was introduced.
Signed-off-by: Mel Gorman <mel@xxxxxxxxx>
Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxxxxxxxxxxxxx>
Cc: Adam Litke <agl@xxxxxxxxxx>
Cc: Avi Kivity <avi@xxxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Minchan Kim <minchan.kim@xxxxxxxxx>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx>
Cc: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
Reviewed-by: Rik van Riel <riel@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/migrate.h | 2 ++
mm/compaction.c | 2 +-
mm/migrate.c | 11 ++++++++++-
3 files changed, 13 insertions(+), 2 deletions(-)
diff -puN include/linux/migrate.h~mmcompaction-memory-compaction-core-do-not-schedule-work-on-other-cpus-for-compaction include/linux/migrate.h
--- a/include/linux/migrate.h~mmcompaction-memory-compaction-core-do-not-schedule-work-on-other-cpus-for-compaction
+++ a/include/linux/migrate.h
@@ -19,6 +19,7 @@ extern int fail_migrate_page(struct addr
struct page *, struct page *);
extern int migrate_prep(void);
+extern int migrate_prep_local(void);
extern int migrate_vmas(struct mm_struct *mm,
const nodemask_t *from, const nodemask_t *to,
unsigned long flags);
@@ -30,6 +31,7 @@ static inline int migrate_pages(struct l
unsigned long private, int offlining) { return -ENOSYS; }
static inline int migrate_prep(void) { return -ENOSYS; }
+static inline int migrate_prep_local(void) { return -ENOSYS; }
static inline int migrate_vmas(struct mm_struct *mm,
const nodemask_t *from, const nodemask_t *to,
diff -puN mm/compaction.c~mmcompaction-memory-compaction-core-do-not-schedule-work-on-other-cpus-for-compaction mm/compaction.c
--- a/mm/compaction.c~mmcompaction-memory-compaction-core-do-not-schedule-work-on-other-cpus-for-compaction
+++ a/mm/compaction.c
@@ -358,7 +358,7 @@ static int compact_zone(struct zone *zon
cc->free_pfn = cc->migrate_pfn + zone->spanned_pages;
cc->free_pfn &= ~(pageblock_nr_pages-1);
- migrate_prep();
+ migrate_prep_local();
while ((ret = compact_finished(zone, cc)) == COMPACT_CONTINUE) {
unsigned long nr_migrate, nr_remaining;
diff -puN mm/migrate.c~mmcompaction-memory-compaction-core-do-not-schedule-work-on-other-cpus-for-compaction mm/migrate.c
--- a/mm/migrate.c~mmcompaction-memory-compaction-core-do-not-schedule-work-on-other-cpus-for-compaction
+++ a/mm/migrate.c
@@ -40,7 +40,8 @@
/*
* migrate_prep() needs to be called before we start compiling a list of pages
- * to be migrated using isolate_lru_page().
+ * to be migrated using isolate_lru_page(). If scheduling work on other CPUs is
+ * undesirable, use migrate_prep_local()
*/
int migrate_prep(void)
{
@@ -55,6 +56,14 @@ int migrate_prep(void)
return 0;
}
+/* Do the necessary work of migrate_prep but not if it involves other CPUs */
+int migrate_prep_local(void)
+{
+ lru_add_drain();
+
+ return 0;
+}
+
/*
* Add isolated pages on the list back to the LRU under page lock
* to avoid leaking evictable pages back onto unevictable list.
_
Patches currently in -mm which might be from mel@xxxxxxxxx are
linux-next.patch
hugetlbfs-kill-applications-that-use-map_noreserve-with-sigbus-instead-of-oom-killer.patch
rmap-remove-anon_vma-check-in-page_address_in_vma.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
mmmigration-take-a-reference-to-the-anon_vma-before-migrating.patch
mmmigration-share-the-anon_vma-ref-counts-between-ksm-and-page-migration.patch
mmmigration-do-not-try-to-migrate-unmapped-anonymous-pages.patch
mmmigration-allow-the-migration-of-pageswapcache-pages.patch
mm-allow-config_migration-to-be-set-without-config_numa-or-memory-hot-remove.patch
mm-export-unusable-free-space-index-via-debugfs.patch
mm-export-fragmentation-index-via-debugfs.patch
mm-move-definition-for-lru-isolation-modes-to-a-header.patch
mmcompaction-memory-compaction-core.patch
mmcompaction-memory-compaction-core-do-not-schedule-work-on-other-cpus-for-compaction.patch
mmcompaction-add-proc-trigger-for-memory-compaction.patch
mmcompaction-add-sys-trigger-for-per-node-memory-compaction.patch
mmcompaction-direct-compact-when-a-high-order-allocation-fails.patch
mmcompaction-direct-compact-when-a-high-order-allocation-fails-fix.patch
mmcompaction-add-a-tunable-that-decides-when-memory-should-be-compacted-and-when-it-should-be-reclaimed.patch
mmcompaction-defer-compaction-using-an-exponential-backoff-when-compaction-fails.patch
mm-introduce-free_pages_prepare.patch
mm-introduce-free_pages_prepare-fix.patch
vmscan-fix-unmapping-behaviour-for-reclaim_swap.patch
vmscan-remove-may_unmap-scan-control.patch
vmscan-remove-all_unreclaimable-scan-control.patch
vmscan-remove-isolate_pages-callback-scan-control.patch
vmscan-remove-may_swap-scan-control.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
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