locking/rtmutex: replace top-waiter and pi_waiters leftmost caching
... with the generic rbtree flavor instead. No changes
in semantics whatsoever.
Link: http://lkml.kernel.org/r/20170719014603.19029-10-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/rtmutex.h b/include/linux/rtmutex.h
index 44fd002..53fcbe9 100644
--- a/include/linux/rtmutex.h
+++ b/include/linux/rtmutex.h
@@ -22,18 +22,17 @@
* The rt_mutex structure
*
* @wait_lock: spinlock to protect the structure
- * @waiters: rbtree root to enqueue waiters in priority order
- * @waiters_leftmost: top waiter
+ * @waiters: rbtree root to enqueue waiters in priority order;
+ * caches top-waiter (leftmost node).
* @owner: the mutex owner
*/
struct rt_mutex {
raw_spinlock_t wait_lock;
- struct rb_root waiters;
- struct rb_node *waiters_leftmost;
+ struct rb_root_cached waiters;
struct task_struct *owner;
#ifdef CONFIG_DEBUG_RT_MUTEXES
int save_state;
- const char *name, *file;
+ const char *name, *file;
int line;
void *magic;
#endif
@@ -84,7 +83,7 @@
#define __RT_MUTEX_INITIALIZER(mutexname) \
{ .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(mutexname.wait_lock) \
- , .waiters = RB_ROOT \
+ , .waiters = RB_ROOT_CACHED \
, .owner = NULL \
__DEBUG_RT_MUTEX_INITIALIZER(mutexname) \
__DEP_MAP_RT_MUTEX_INITIALIZER(mutexname)}