[Qemu-devel] [PATCH v2 07/13] qemu-thread: call cpu_relax() while spinning

[Emilio G. Cota]

Signed-off-by: Emilio G. Cota <c...@braap.org>
---
 include/qemu/thread.h | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/include/qemu/thread.h b/include/qemu/thread.h
index 1aa843b..599965e 100644
--- a/include/qemu/thread.h
+++ b/include/qemu/thread.h
@@ -2,6 +2,7 @@
 #define __QEMU_THREAD_H 1
 
 #include <errno.h>
+#include "qemu/processor.h"
 #include "qemu/atomic.h"
 
 typedef struct QemuMutex QemuMutex;
@@ -74,7 +75,9 @@ static inline void qemu_spin_init(QemuSpin *spin)
 static inline void qemu_spin_lock(QemuSpin *spin)
 {
     do {
-        while (atomic_read(&spin->value));
+        while (atomic_read(&spin->value)) {
+            cpu_relax();
+        }
     } while (atomic_xchg(&spin->value, true));
 }
 
-- 
2.5.0