[RFC 1/5] meminfo: add a per node counter for balloon drivers

[Nico Pache <npache@redhat.com>]

Add NR_BALLOON_PAGES counter to track memory used by balloon drivers and
expose it through /proc/meminfo and other memory reporting interfaces.

Signed-off-by: Nico Pache <npache@redhat.com>
---
 fs/proc/meminfo.c      | 2 ++
 include/linux/mmzone.h | 1 +
 mm/memcontrol.c        | 1 +
 mm/show_mem.c          | 4 +++-
 mm/vmstat.c            | 1 +
 5 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/fs/proc/meminfo.c b/fs/proc/meminfo.c
index 8ba9b1472390..83be312159c9 100644
--- a/fs/proc/meminfo.c
+++ b/fs/proc/meminfo.c
@@ -162,6 +162,8 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
 	show_val_kb(m, "Unaccepted:     ",
 		    global_zone_page_state(NR_UNACCEPTED));
 #endif
+	show_val_kb(m, "Balloon:        ",
+		    global_node_page_state(NR_BALLOON_PAGES));
 
 	hugetlb_report_meminfo(m);
 
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 9540b41894da..71d3ff19267a 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -223,6 +223,7 @@ enum node_stat_item {
 #ifdef CONFIG_HUGETLB_PAGE
 	NR_HUGETLB,
 #endif
+	NR_BALLOON_PAGES,
 	NR_VM_NODE_STAT_ITEMS
 };
 
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 4de6acb9b8ec..182b44646bfa 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1377,6 +1377,7 @@ static const struct memory_stat memory_stats[] = {
 #ifdef CONFIG_HUGETLB_PAGE
 	{ "hugetlb",			NR_HUGETLB			},
 #endif
+	{ "nr_balloon_pages",		NR_BALLOON_PAGES		},
 
 	/* The memory events */
 	{ "workingset_refault_anon",	WORKINGSET_REFAULT_ANON		},
diff --git a/mm/show_mem.c b/mm/show_mem.c
index 43afb56abbd3..6af13bcd2ab3 100644
--- a/mm/show_mem.c
+++ b/mm/show_mem.c
@@ -260,6 +260,7 @@ static void show_free_areas(unsigned int filter, nodemask_t *nodemask, int max_z
 			" pagetables:%lukB"
 			" sec_pagetables:%lukB"
 			" all_unreclaimable? %s"
+			" Balloon:%lukB"
 			"\n",
 			pgdat->node_id,
 			K(node_page_state(pgdat, NR_ACTIVE_ANON)),
@@ -285,7 +286,8 @@ static void show_free_areas(unsigned int filter, nodemask_t *nodemask, int max_z
 #endif
 			K(node_page_state(pgdat, NR_PAGETABLE)),
 			K(node_page_state(pgdat, NR_SECONDARY_PAGETABLE)),
-			str_yes_no(pgdat->kswapd_failures >= MAX_RECLAIM_RETRIES));
+			str_yes_no(pgdat->kswapd_failures >= MAX_RECLAIM_RETRIES),
+			K(node_page_state(pgdat, NR_BALLOON_PAGES)));
 	}
 
 	for_each_populated_zone(zone) {
diff --git a/mm/vmstat.c b/mm/vmstat.c
index 16bfe1c694dd..d3b11891a942 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -1276,6 +1276,7 @@ const char * const vmstat_text[] = {
 #ifdef CONFIG_HUGETLB_PAGE
 	"nr_hugetlb",
 #endif
+	"nr_balloon_pages",
 	/* system-wide enum vm_stat_item counters */
 	"nr_dirty_threshold",
 	"nr_dirty_background_threshold",
-- 
2.48.1