The current implementation only deflates 256 pages even when a user specifies more than that via the oom_pages module param. This patch enables the deflating of up to oom_pages pages if there are enough inflated pages.
Signed-off-by: Wei Wang <[email protected]> Cc: Michael S. Tsirkin <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Tetsuo Handa <[email protected]> --- drivers/virtio/virtio_balloon.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 1ecd15a..ab55cf8 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -43,8 +43,8 @@ #define OOM_VBALLOON_DEFAULT_PAGES 256 #define VIRTBALLOON_OOM_NOTIFY_PRIORITY 80 -static int oom_pages = OOM_VBALLOON_DEFAULT_PAGES; -module_param(oom_pages, int, S_IRUSR | S_IWUSR); +static unsigned int oom_pages = OOM_VBALLOON_DEFAULT_PAGES; +module_param(oom_pages, uint, 0600); MODULE_PARM_DESC(oom_pages, "pages to free on OOM"); #ifdef CONFIG_BALLOON_COMPACTION @@ -359,16 +359,20 @@ static int virtballoon_oom_notify(struct notifier_block *self, { struct virtio_balloon *vb; unsigned long *freed; - unsigned num_freed_pages; + unsigned int npages = oom_pages; vb = container_of(self, struct virtio_balloon, nb); if (!virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_DEFLATE_ON_OOM)) return NOTIFY_OK; freed = parm; - num_freed_pages = leak_balloon(vb, oom_pages); + + /* Don't deflate more than the number of inflated pages */ + while (npages && atomic64_read(&vb->num_pages)) + npages -= leak_balloon(vb, npages); + update_balloon_size(vb); - *freed += num_freed_pages; + *freed += oom_pages - npages; return NOTIFY_OK; } -- 2.7.4 _______________________________________________ Virtualization mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/virtualization
