These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / kernel / locking / mcs_spinlock.h

diff --git a/kernel/kernel/locking/mcs_spinlock.h b/kernel/kernel/locking/mcs_spinlock.h
index 75e114b..5b9102a 100644 (file)
--- a/kernel/kernel/locking/mcs_spinlock.h
+++ b/kernel/kernel/locking/mcs_spinlock.h
@@ -17,6 +17,7 @@
 struct mcs_spinlock {
        struct mcs_spinlock *next;
        int locked; /* 1 if lock acquired */
+       int count;  /* nesting count, see qspinlock.c */
 };
 
 #ifndef arch_mcs_spin_lock_contended
@@ -66,7 +67,7 @@ void mcs_spin_lock(struct mcs_spinlock **lock, struct mcs_spinlock *node)
        node->locked = 0;
        node->next   = NULL;
 
-       prev = xchg(lock, node);
+       prev = xchg_acquire(lock, node);
        if (likely(prev == NULL)) {
                /*
                 * Lock acquired, don't need to set node->locked to 1. Threads
@@ -97,7 +98,7 @@ void mcs_spin_unlock(struct mcs_spinlock **lock, struct mcs_spinlock *node)
                /*
                 * Release the lock by setting it to NULL
                 */
-               if (likely(cmpxchg(lock, node, NULL) == node))
+               if (likely(cmpxchg_release(lock, node, NULL) == node))
                        return;
                /* Wait until the next pointer is set */
                while (!(next = READ_ONCE(node->next)))