xen/tmem: Don't use self[ballooning|shrinking] if frontswap is off.

There is no point. We would just squeeze the guest to put more and
more pages in the swap disk without any purpose.

The only time it makes sense to use the selfballooning and shrinking
is when frontswap is being utilized.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/xen/tmem.c b/drivers/xen/tmem.c
index c1df0ff8987..18e8bd8fa94 100644
--- a/drivers/xen/tmem.c
+++ b/drivers/xen/tmem.c
@@ -403,6 +403,14 @@ static int xen_tmem_init(void)
 	}
 #endif
 #ifdef CONFIG_XEN_SELFBALLOONING
+	/*
+	 * There is no point of driving pages to the swap system if they
+	 * aren't going anywhere in tmem universe.
+	 */
+	if (!frontswap) {
+		selfshrinking = false;
+		selfballooning = false;
+	}
 	xen_selfballoon_init(selfballooning, selfshrinking);
 #endif
 	return 0;