Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
IronPort-SDR: pbl/nf12h9n7RMO5kkoXm8bkR7t+nkQJhGxDFmM2XFJBqGKqyvBkb+9rJFb/WLDG3DbcnO/XrZ
 i2doJNSRIxZw==
IronPort-SDR: u6tiM7EChXKnap2WU9nMY6+rO96oNcpw0iz5J5zR071El4CGIbdwlA9B6sNg7rODVYeXV3RJ+l
 pwvJrrL7vYMw==
Subject: [PATCH 06/10] mm/vmscan: add page demotion counter
To:     linux-kernel@vger.kernel.org
Cc:     linux-mm@kvack.org, Dave Hansen <dave.hansen@linux.intel.com>,
        yang.shi@linux.alibaba.com, rientjes@google.com,
        ying.huang@intel.com, dan.j.williams@intel.com, david@redhat.com,
        osalvador@suse.de
From:   Dave Hansen <dave.hansen@linux.intel.com>
Date:   Thu, 04 Mar 2021 16:00:00 -0800
References: <20210304235949.7922C1C3@viggo.jf.intel.com>
In-Reply-To: <20210304235949.7922C1C3@viggo.jf.intel.com>
Message-Id: <20210305000000.48BA4A97@viggo.jf.intel.com>
Precedence: bulk


From: Yang Shi <yang.shi@linux.alibaba.com>

Account the number of demoted pages into reclaim_state->nr_demoted.

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()
]

Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: osalvador <osalvador@suse.de>

--

Changes since 202010:
 * remove unused scan-control 'demoted' field
---

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

diff -puN include/linux/vm_event_item.h~mm-vmscan-add-page-demotion-counter include/linux/vm_event_item.h
--- a/include/linux/vm_event_item.h~mm-vmscan-add-page-demotion-counter	2021-03-04 15:35:57.698806425 -0800
+++ b/include/linux/vm_event_item.h	2021-03-04 15:35:57.719806425 -0800
@@ -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,
diff -puN mm/vmscan.c~mm-vmscan-add-page-demotion-counter mm/vmscan.c
--- a/mm/vmscan.c~mm-vmscan-add-page-demotion-counter	2021-03-04 15:35:57.700806425 -0800
+++ b/mm/vmscan.c	2021-03-04 15:35:57.724806425 -0800
@@ -1118,6 +1118,11 @@ 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;
 }
 
diff -puN mm/vmstat.c~mm-vmscan-add-page-demotion-counter mm/vmstat.c
--- a/mm/vmstat.c~mm-vmscan-add-page-demotion-counter	2021-03-04 15:35:57.708806425 -0800
+++ b/mm/vmstat.c	2021-03-04 15:35:57.726806425 -0800
@@ -1244,6 +1244,8 @@ const char * const vmstat_text[] = {
 	"pgreuse",
 	"pgsteal_kswapd",
 	"pgsteal_direct",
+	"pgdemote_kswapd",
+	"pgdemote_direct",
 	"pgscan_kswapd",
 	"pgscan_direct",
 	"pgscan_direct_throttle",
_