Fix cstyle issue in mutex.h

This patch only addresses the issues identified by the style checker
in mutex.h.  It contains no functional changes.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tim Chase <tim@chase2k.com>
Issue #435

include/sys/mutex.h

@@ -1,4 +1,4 @@
-/*****************************************************************************\
+/*
  *  Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC.
  *  Copyright (C) 2007 The Regents of the University of California.
  *  Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
@@ -20,7 +20,7 @@
  *
  *  You should have received a copy of the GNU General Public License along
  *  with the SPL.  If not, see <http://www.gnu.org/licenses/>.
-\*****************************************************************************/
+ */
 
 #ifndef _SPL_MUTEX_H
 #define	_SPL_MUTEX_H
@@ -38,10 +38,6 @@ typedef enum {
 #if defined(HAVE_MUTEX_OWNER) && defined(CONFIG_SMP) && \
 	!defined(CONFIG_DEBUG_MUTEXES)
 
-/*
- * We define a 1-field struct rather than a straight typedef to enforce type
- * safety.
- */
 typedef struct {
 	struct mutex		m;
 	spinlock_t		m_lock;	/* used for serializing mutex_exit */
@@ -51,13 +47,13 @@ static inline kthread_t *
 mutex_owner(kmutex_t *mp)
 {
 #if defined(HAVE_MUTEX_OWNER_TASK_STRUCT)
-	return ACCESS_ONCE(mp->m.owner);
+	return (ACCESS_ONCE(mp->m.owner));
 #else
 	struct thread_info *owner = ACCESS_ONCE(mp->m.owner);
 	if (owner)
-		return owner->task;
+		return (owner->task);
 
-	return NULL;
+	return (NULL);
 #endif
 }
 
@@ -66,26 +62,26 @@ mutex_owner(kmutex_t *mp)
 #define	MUTEX_NOT_HELD(mp)	(!MUTEX_HELD(mp))
 #undef mutex_init
 #define	mutex_init(mp, name, type, ibc)				\
-({                                                                      \
+{								\
 	static struct lock_class_key __key;			\
 	ASSERT(type == MUTEX_DEFAULT);				\
 								\
 	__mutex_init(&(mp)->m, #mp, &__key);			\
 	spin_lock_init(&(mp)->m_lock);				\
-})
+}
 
 #undef mutex_destroy
 #define	mutex_destroy(mp)					\
-({                                                                      \
+{								\
 	VERIFY3P(mutex_owner(mp), ==, NULL);			\
-})
+}
 
 #define	mutex_tryenter(mp)	mutex_trylock(&(mp)->m)
 #define	mutex_enter(mp)						\
-({                                                                      \
+{								\
 	ASSERT3P(mutex_owner(mp), !=, current);			\
 	mutex_lock(&(mp)->m);					\
-})
+}
 /*
  * The reason for the spinlock:
  *
@@ -106,17 +102,17 @@ mutex_owner(kmutex_t *mp)
  * See http://lwn.net/Articles/575477/ for the information about the race.
  */
 #define	mutex_exit(mp)						\
-({									\
+{								\
 	spin_lock(&(mp)->m_lock);				\
 	mutex_unlock(&(mp)->m);					\
 	spin_unlock(&(mp)->m_lock);				\
-})
+}
 
 #else /* HAVE_MUTEX_OWNER */
 
 typedef struct {
 	struct mutex		m_mutex;
-	spinlock_t m_lock;
+	spinlock_t		m_lock;	/* used for serializing mutex_exit */
 	kthread_t		*m_owner;
 } kmutex_t;
 
@@ -147,20 +143,20 @@ spl_mutex_clear_owner(kmutex_t *mp)
  */
 #undef mutex_init
 #define	mutex_init(mp, name, type, ibc)				\
-({                                                                      \
+{								\
 	static struct lock_class_key __key;			\
 	ASSERT(type == MUTEX_DEFAULT);				\
 								\
 	__mutex_init(MUTEX(mp), #mp, &__key);			\
 	spin_lock_init(&(mp)->m_lock);				\
 	spl_mutex_clear_owner(mp);				\
-})
+}
 
 #undef mutex_destroy
 #define	mutex_destroy(mp)					\
-({                                                                      \
+{								\
 	VERIFY3P(mutex_owner(mp), ==, NULL);			\
-})
+}
 
 #define	mutex_tryenter(mp)					\
 ({								\
@@ -173,19 +169,19 @@ spl_mutex_clear_owner(kmutex_t *mp)
 })
 
 #define	mutex_enter(mp)						\
-({                                                                      \
+{								\
 	ASSERT3P(mutex_owner(mp), !=, current);			\
 	mutex_lock(MUTEX(mp));					\
 	spl_mutex_set_owner(mp);				\
-})
+}
 
 #define	mutex_exit(mp)						\
-({                                                                      \
+{								\
 	spin_lock(&(mp)->m_lock);				\
 	spl_mutex_clear_owner(mp);				\
 	mutex_unlock(MUTEX(mp));				\
 	spin_unlock(&(mp)->m_lock);				\
-})
+}
 
 #endif /* HAVE_MUTEX_OWNER */