Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

torvalds · torvalds · commit 1acf93ca6c53 · 2018-11-11T16:18:10.000-06:00
Pull locking build fix from Thomas Gleixner:
 "A single fix for a build fail with CONFIG_PROFILE_ALL_BRANCHES=y in
  the qspinlock code"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/qspinlock: Fix compile error
diff --git a/arch/x86/include/asm/qspinlock.h b/arch/x86/include/asm/qspinlock.h
@@ -13,12 +13,15 @@
 #define queued_fetch_set_pending_acquire queued_fetch_set_pending_acquire
 static __always_inline u32 queued_fetch_set_pending_acquire(struct qspinlock *lock)
 {
-	u32 val = 0;
-
-	if (GEN_BINARY_RMWcc(LOCK_PREFIX "btsl", lock->val.counter, c,
-			     "I", _Q_PENDING_OFFSET))
-		val |= _Q_PENDING_VAL;
+	u32 val;
 
+	/*
+	 * We can't use GEN_BINARY_RMWcc() inside an if() stmt because asm goto
+	 * and CONFIG_PROFILE_ALL_BRANCHES=y results in a label inside a
+	 * statement expression, which GCC doesn't like.
+	 */
+	val = GEN_BINARY_RMWcc(LOCK_PREFIX "btsl", lock->val.counter, c,
+			       "I", _Q_PENDING_OFFSET) * _Q_PENDING_VAL;
 	val |= atomic_read(&lock->val) & ~_Q_PENDING_MASK;
 
 	return val;
