rwlock_reader_lock: fix lock list jammed up

2016-03-03 22:47:48 +09:00
parent 8ebb3a4231
commit 26c0180374
2 changed files with 44 additions and 31 deletions
--- a/arch/x86/kernel/include/ihk/atomic.h
+++ b/arch/x86/kernel/include/ihk/atomic.h
@ -202,4 +202,17 @@ static inline unsigned long atomic_cmpxchg8(unsigned long *addr,
 	return oldval;
 }

+static inline unsigned long atomic_cmpxchg4(unsigned int *addr,
+		unsigned int oldval,
+		unsigned int newval)
+{
+	asm volatile("lock; cmpxchgl %2, %1\n"
+		     : "=a" (oldval), "+m" (*addr)
+		     : "r" (newval), "0" (oldval)
+		     : "memory"
+	);
+
+	return oldval;
+}
+
 #endif