On 18.04.24 08:26, zhenwei pi wrote:
Memory allocation stall counter represents the performance/latency of
memory allocation, expose this counter to the host side by virtio
balloon device via out-of-bound way.
Signed-off-by: zhenwei pi <pizhenwei@xxxxxxxxxxxxx>
---
drivers/virtio/virtio_balloon.c | 20 +++++++++++++++++++-
include/uapi/linux/virtio_balloon.h | 6 ++++--
2 files changed, 23 insertions(+), 3 deletions(-)
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index fd19934a847f..e88e6573afa5 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -321,7 +321,7 @@ static unsigned int update_balloon_stats(struct virtio_balloon *vb)
unsigned long events[NR_VM_EVENT_ITEMS];
struct sysinfo i;
unsigned int idx = 0;
- long available;
+ long available, stall = 0;
unsigned long caches;
all_vm_events(events);
@@ -338,6 +338,24 @@ static unsigned int update_balloon_stats(struct virtio_balloon *vb)
update_stat(vb, idx++, VIRTIO_BALLOON_S_MAJFLT, events[PGMAJFAULT]);
update_stat(vb, idx++, VIRTIO_BALLOON_S_MINFLT, events[PGFAULT]);
update_stat(vb, idx++, VIRTIO_BALLOON_S_OOM_KILL, events[OOM_KILL]);
+
+ /* sum all the stall events */
+#ifdef CONFIG_ZONE_DMA
+ stall += events[ALLOCSTALL_DMA];
+#endif
+#ifdef CONFIG_ZONE_DMA32
+ stall += events[ALLOCSTALL_DMA32];
+#endif
+#ifdef CONFIG_HIGHMEM
+ stall += events[ALLOCSTALL_HIGH];
+#endif
+#ifdef CONFIG_ZONE_DEVICE
+ stall += events[ALLOCSTALL_DEVICE];
+#endif
Naive me would think that ALLOCSTALL_DEVICE is always 0. :)
Likely we should just do:
for (zid = 0; zid < MAX_NR_ZONES; zid++)
stall += events[ALLOCSTALL_NORMAL - ZONE_NORMAL + zid];
(see isolate_lru_folios() -> __count_zid_vm_events(), where we realy on
the same ordering)
Apart form that, LGTM.
--
Cheers,
David / dhildenb
