From 7f354a548d1cb6bb01b6ee74aee9264aa152f1ec Mon Sep 17 00:00:00 2001 From: David Rientjes Date: Wed, 22 Feb 2017 15:44:50 -0800 Subject: [PATCH] mm, compaction: add vmstats for kcompactd work A "compact_daemon_wake" vmstat exists that represents the number of times kcompactd has woken up. This doesn't represent how much work it actually did, though. It's useful to understand how much compaction work is being done by kcompactd versus other methods such as direct compaction and explicitly triggered per-node (or system) compaction. This adds two new vmstats: "compact_daemon_migrate_scanned" and "compact_daemon_free_scanned" to represent the number of pages kcompactd has scanned as part of its migration scanner and freeing scanner, respectively. These values are still accounted for in the general "compact_migrate_scanned" and "compact_free_scanned" for compatibility. It could be argued that explicitly triggered compaction could also be tracked separately, and that could be added if others find it useful. Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1612071749390.69852@chino.kir.corp.google.com Signed-off-by: David Rientjes Acked-by: Vlastimil Babka Cc: Michal Hocko Cc: Joonsoo Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/vm_event_item.h | 1 + mm/compaction.c | 22 +++++++++++++++++++--- mm/internal.h | 2 ++ mm/vmstat.c | 2 ++ 4 files changed, 24 insertions(+), 3 deletions(-) diff --git a/include/linux/vm_event_item.h b/include/linux/vm_event_item.h index 4d6ec58a8d45..6aa1b6cb5828 100644 --- a/include/linux/vm_event_item.h +++ b/include/linux/vm_event_item.h @@ -56,6 +56,7 @@ enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT, COMPACTISOLATED, COMPACTSTALL, COMPACTFAIL, COMPACTSUCCESS, KCOMPACTD_WAKE, + KCOMPACTD_MIGRATE_SCANNED, KCOMPACTD_FREE_SCANNED, #endif #ifdef CONFIG_HUGETLB_PAGE HTLB_BUDDY_PGALLOC, HTLB_BUDDY_PGALLOC_FAIL, diff --git a/mm/compaction.c b/mm/compaction.c index 949198d01260..c6178bbd3e04 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -548,7 +548,7 @@ isolate_fail: if (blockpfn == end_pfn) update_pageblock_skip(cc, valid_page, total_isolated, false); - count_compact_events(COMPACTFREE_SCANNED, nr_scanned); + cc->total_free_scanned += nr_scanned; if (total_isolated) count_compact_events(COMPACTISOLATED, total_isolated); return total_isolated; @@ -931,7 +931,7 @@ isolate_fail: trace_mm_compaction_isolate_migratepages(start_pfn, low_pfn, nr_scanned, nr_isolated); - count_compact_events(COMPACTMIGRATE_SCANNED, nr_scanned); + cc->total_migrate_scanned += nr_scanned; if (nr_isolated) count_compact_events(COMPACTISOLATED, nr_isolated); @@ -1631,6 +1631,9 @@ out: zone->compact_cached_free_pfn = free_pfn; } + count_compact_events(COMPACTMIGRATE_SCANNED, cc->total_migrate_scanned); + count_compact_events(COMPACTFREE_SCANNED, cc->total_free_scanned); + trace_mm_compaction_end(start_pfn, cc->migrate_pfn, cc->free_pfn, end_pfn, sync, ret); @@ -1645,6 +1648,8 @@ static enum compact_result compact_zone_order(struct zone *zone, int order, struct compact_control cc = { .nr_freepages = 0, .nr_migratepages = 0, + .total_migrate_scanned = 0, + .total_free_scanned = 0, .order = order, .gfp_mask = gfp_mask, .zone = zone, @@ -1757,6 +1762,8 @@ static void compact_node(int nid) struct zone *zone; struct compact_control cc = { .order = -1, + .total_migrate_scanned = 0, + .total_free_scanned = 0, .mode = MIGRATE_SYNC, .ignore_skip_hint = true, .whole_zone = true, @@ -1883,6 +1890,8 @@ static void kcompactd_do_work(pg_data_t *pgdat) struct zone *zone; struct compact_control cc = { .order = pgdat->kcompactd_max_order, + .total_migrate_scanned = 0, + .total_free_scanned = 0, .classzone_idx = pgdat->kcompactd_classzone_idx, .mode = MIGRATE_SYNC_LIGHT, .ignore_skip_hint = true, @@ -1891,7 +1900,7 @@ static void kcompactd_do_work(pg_data_t *pgdat) }; trace_mm_compaction_kcompactd_wake(pgdat->node_id, cc.order, cc.classzone_idx); - count_vm_event(KCOMPACTD_WAKE); + count_compact_event(KCOMPACTD_WAKE); for (zoneid = 0; zoneid <= cc.classzone_idx; zoneid++) { int status; @@ -1909,6 +1918,8 @@ static void kcompactd_do_work(pg_data_t *pgdat) cc.nr_freepages = 0; cc.nr_migratepages = 0; + cc.total_migrate_scanned = 0; + cc.total_free_scanned = 0; cc.zone = zone; INIT_LIST_HEAD(&cc.freepages); INIT_LIST_HEAD(&cc.migratepages); @@ -1927,6 +1938,11 @@ static void kcompactd_do_work(pg_data_t *pgdat) defer_compaction(zone, cc.order); } + count_compact_events(KCOMPACTD_MIGRATE_SCANNED, + cc.total_migrate_scanned); + count_compact_events(KCOMPACTD_FREE_SCANNED, + cc.total_free_scanned); + VM_BUG_ON(!list_empty(&cc.freepages)); VM_BUG_ON(!list_empty(&cc.migratepages)); } diff --git a/mm/internal.h b/mm/internal.h index bfad3b5d2665..9ad04fc6eefe 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -175,6 +175,8 @@ struct compact_control { struct list_head migratepages; /* List of pages being migrated */ unsigned long nr_freepages; /* Number of isolated free pages */ unsigned long nr_migratepages; /* Number of pages to migrate */ + unsigned long total_migrate_scanned; + unsigned long total_free_scanned; unsigned long free_pfn; /* isolate_freepages search base */ unsigned long migrate_pfn; /* isolate_migratepages search base */ unsigned long last_migrated_pfn;/* Not yet flushed page being freed */ diff --git a/mm/vmstat.c b/mm/vmstat.c index 7c28df36f50f..69f9aff39a2e 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -1038,6 +1038,8 @@ const char * const vmstat_text[] = { "compact_fail", "compact_success", "compact_daemon_wake", + "compact_daemon_migrate_scanned", + "compact_daemon_free_scanned", #endif #ifdef CONFIG_HUGETLB_PAGE -- 2.20.1