From: David Rientjes <rientjes@xxxxxxxxxx> Subject: 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@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: David Rientjes <rientjes@xxxxxxxxxx> Acked-by: Vlastimil Babka <vbabka@xxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- 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 -puN include/linux/vm_event_item.h~mm-compaction-add-vmstats-for-kcompactd-work include/linux/vm_event_item.h --- a/include/linux/vm_event_item.h~mm-compaction-add-vmstats-for-kcompactd-work +++ a/include/linux/vm_event_item.h @@ -56,6 +56,7 @@ enum vm_event_item { PGPGIN, PGPGOUT, PS 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 -puN mm/compaction.c~mm-compaction-add-vmstats-for-kcompactd-work mm/compaction.c --- a/mm/compaction.c~mm-compaction-add-vmstats-for-kcompactd-work +++ a/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_ 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 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 }; 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 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 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 -puN mm/internal.h~mm-compaction-add-vmstats-for-kcompactd-work mm/internal.h --- a/mm/internal.h~mm-compaction-add-vmstats-for-kcompactd-work +++ a/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 -puN mm/vmstat.c~mm-compaction-add-vmstats-for-kcompactd-work mm/vmstat.c --- a/mm/vmstat.c~mm-compaction-add-vmstats-for-kcompactd-work +++ a/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 _ -- 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
