A simple true/false internal state does not allow multiple users. Fix
this within the existing interface by converting to a counter, so long
as the counter is elevated, ballooning is inhibited.
Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
Reviewed-by: Peter Xu <peterx@xxxxxxxxxx>
Reviewed-by: Cornelia Huck <cohuck@xxxxxxxxxx>
Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
---
balloon.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)
diff --git a/balloon.c b/balloon.c
index 6bf0a9681377..931987983858 100644
--- a/balloon.c
+++ b/balloon.c
@@ -26,6 +26,7 @@
#include "qemu/osdep.h"
#include "qemu-common.h"
+#include "qemu/atomic.h"
#include "exec/cpu-common.h"
#include "sysemu/kvm.h"
#include "sysemu/balloon.h"
@@ -37,16 +38,22 @@
static QEMUBalloonEvent *balloon_event_fn;
static QEMUBalloonStatus *balloon_stat_fn;
static void *balloon_opaque;
-static bool balloon_inhibited;
+static int balloon_inhibit_count;
bool qemu_balloon_is_inhibited(void)
{
- return balloon_inhibited;
+ return atomic_read(&balloon_inhibit_count) > 0;
}
void qemu_balloon_inhibit(bool state)
{
- balloon_inhibited = state;
+ if (state) {
+ atomic_inc(&balloon_inhibit_count);
+ } else {
+ atomic_dec(&balloon_inhibit_count);
+ }
+
+ assert(atomic_read(&balloon_inhibit_count) >= 0);
}
static bool have_balloon(Error **errp)
--
2.18.0
