+ mm-vmscan-add-page-demotion-counter.patch added to -mm tree

+ mm-vmscan-add-page-demotion-counter.patch added to -mm tree

[akpm]

The patch titled
     Subject: mm/vmscan: add page demotion counter
has been added to the -mm tree.  Its filename is
     mm-vmscan-add-page-demotion-counter.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-vmscan-add-page-demotion-counter.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-vmscan-add-page-demotion-counter.patch

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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

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there every 3-4 working days

------------------------------------------------------
From: Yang Shi <yang.shi@linux.alibaba.com>
Subject: mm/vmscan: add page demotion counter

Account the number of demoted pages.

Add pgdemote_kswapd and pgdemote_direct VM counters showed in
/proc/vmstat.

[ daveh:
   - __count_vm_events() a bit, and made them look at the THP
     size directly rather than getting data from migrate_pages()
]

Link: https://lkml.kernel.org/r/20210715055145.195411-6-ying.huang@intel.com
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Wei Xu <weixugc@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Greg Thelen <gthelen@google.com>
Cc: Keith Busch <kbusch@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/vm_event_item.h |    2 ++
 mm/vmscan.c                   |    5 +++++
 mm/vmstat.c                   |    2 ++
 3 files changed, 9 insertions(+)

--- a/include/linux/vm_event_item.h~mm-vmscan-add-page-demotion-counter
+++ a/include/linux/vm_event_item.h
@@ -33,6 +33,8 @@ enum vm_event_item { PGPGIN, PGPGOUT, PS
 		PGREUSE,
 		PGSTEAL_KSWAPD,
 		PGSTEAL_DIRECT,
+		PGDEMOTE_KSWAPD,
+		PGDEMOTE_DIRECT,
 		PGSCAN_KSWAPD,
 		PGSCAN_DIRECT,
 		PGSCAN_DIRECT_THROTTLE,
--- a/mm/vmscan.c~mm-vmscan-add-page-demotion-counter
+++ a/mm/vmscan.c
@@ -1322,6 +1322,11 @@ static unsigned int demote_page_list(str
 			    target_nid, MIGRATE_ASYNC, MR_DEMOTION,
 			    &nr_succeeded);
 
+	if (current_is_kswapd())
+		__count_vm_events(PGDEMOTE_KSWAPD, nr_succeeded);
+	else
+		__count_vm_events(PGDEMOTE_DIRECT, nr_succeeded);
+
 	return nr_succeeded;
 }
 
--- a/mm/vmstat.c~mm-vmscan-add-page-demotion-counter
+++ a/mm/vmstat.c
@@ -1217,6 +1217,8 @@ const char * const vmstat_text[] = {
 	"pgreuse",
 	"pgsteal_kswapd",
 	"pgsteal_direct",
+	"pgdemote_kswapd",
+	"pgdemote_direct",
 	"pgscan_kswapd",
 	"pgscan_direct",
 	"pgscan_direct_throttle",
_

Patches currently in -mm which might be from yang.shi@linux.alibaba.com are

mm-migrate-enable-returning-precise-migrate_pages-success-count.patch
mm-vmscan-add-page-demotion-counter.patch