locking: Clean up pvqspinlock warning (0b792bf5) · Commits · 戴 / test

- Rename the on-stack variable to match the datastructure variable, - place the cmpxchg back under the comment that explains it, - clean up the WARN() statement to avoid superfluous conditionals and line-breaks. Signed-off-by:

Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Waiman Long <Waiman.Long@hp.com> Cc: linux-kernel@vger.kernel.org Signed-off-by:

Ingo Molnar <mingo@kernel.org>

kernel/locking/qspinlock_paravirt.h

+7 −6

Original line number	Diff line number	Diff line
		@@ -287,20 +287,21 @@ __visible void __pv_queued_spin_unlock(struct qspinlock *lock)
		{
		struct __qspinlock l = (void )lock;
		struct pv_node *node;
		u8 lockval = cmpxchg(&l->locked, _Q_LOCKED_VAL, 0);
		u8 locked;

		/*
		* We must not unlock if SLOW, because in that case we must first
		* unhash. Otherwise it would be possible to have multiple @lock
		* entries, which would be BAD.
		*/
		if (likely(lockval == _Q_LOCKED_VAL))
		locked = cmpxchg(&l->locked, _Q_LOCKED_VAL, 0);
		if (likely(locked == _Q_LOCKED_VAL))
		return;

		if (unlikely(lockval != _Q_SLOW_VAL)) {
		if (debug_locks_silent)
		return;
		WARN(1, "pvqspinlock: lock %p has corrupted value 0x%x!\n", lock, atomic_read(&lock->val));
		if (unlikely(locked != _Q_SLOW_VAL)) {
		WARN(!debug_locks_silent,
		"pvqspinlock: lock 0x%lx has corrupted value 0x%x!\n",
		(unsigned long)lock, atomic_read(&lock->val));
		return;
		}

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