virtio_balloon: include disk/file caches memory statistics
Add a new field VIRTIO_BALLOON_S_CACHES to virtio_balloon memory
statistics protocol. The value represents all disk/file caches.
In this case it corresponds to the sum of values
Buffers+Cached+SwapCached from /proc/meminfo.
Signed-off-by: Tomáš Golembiovský <tgolembi@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index a1fb52c..dfe5684 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -257,11 +257,13 @@ static unsigned int update_balloon_stats(struct virtio_balloon *vb)
struct sysinfo i;
unsigned int idx = 0;
long available;
+ unsigned long caches;
all_vm_events(events);
si_meminfo(&i);
available = si_mem_available();
+ caches = global_node_page_state(NR_FILE_PAGES);
#ifdef CONFIG_VM_EVENT_COUNTERS
update_stat(vb, idx++, VIRTIO_BALLOON_S_SWAP_IN,
@@ -277,6 +279,8 @@ static unsigned int update_balloon_stats(struct virtio_balloon *vb)
pages_to_bytes(i.totalram));
update_stat(vb, idx++, VIRTIO_BALLOON_S_AVAIL,
pages_to_bytes(available));
+ update_stat(vb, idx++, VIRTIO_BALLOON_S_CACHES,
+ pages_to_bytes(caches));
return idx;
}
diff --git a/include/uapi/linux/virtio_balloon.h b/include/uapi/linux/virtio_balloon.h
index 343d7dd..4e8b830 100644
--- a/include/uapi/linux/virtio_balloon.h
+++ b/include/uapi/linux/virtio_balloon.h
@@ -52,7 +52,8 @@ struct virtio_balloon_config {
#define VIRTIO_BALLOON_S_MEMFREE 4 /* Total amount of free memory */
#define VIRTIO_BALLOON_S_MEMTOT 5 /* Total amount of memory */
#define VIRTIO_BALLOON_S_AVAIL 6 /* Available memory as in /proc */
-#define VIRTIO_BALLOON_S_NR 7
+#define VIRTIO_BALLOON_S_CACHES 7 /* Disk caches */
+#define VIRTIO_BALLOON_S_NR 8
/*
* Memory statistics structure.