1 files changed, 41 insertions, 0 deletions
diff --git a/arch/loongarch/include/asm/qspinlock.h b/arch/loongarch/include/asm/qspinlock.h
new file mode 100644
index 000000000000..e76d3aa1e1eb
--- /dev/null
+++ b/arch/loongarch/include/asm/qspinlock.h
@@ -0,0 +1,41 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_LOONGARCH_QSPINLOCK_H
+#define _ASM_LOONGARCH_QSPINLOCK_H
+
+#include <linux/jump_label.h>
+
+#ifdef CONFIG_PARAVIRT
+
+DECLARE_STATIC_KEY_FALSE(virt_spin_lock_key);
+
+#define virt_spin_lock virt_spin_lock
+
+static inline bool virt_spin_lock(struct qspinlock *lock)
+{
+	int val;
+
+	if (!static_branch_unlikely(&virt_spin_lock_key))
+		return false;
+
+	/*
+	 * On hypervisors without PARAVIRT_SPINLOCKS support we fall
+	 * back to a Test-and-Set spinlock, because fair locks have
+	 * horrible lock 'holder' preemption issues.
+	 */
+
+__retry:
+	val = atomic_read(&lock->val);
+
+	if (val || !atomic_try_cmpxchg(&lock->val, &val, _Q_LOCKED_VAL)) {
+		cpu_relax();
+		goto __retry;
+	}
+
+	return true;
+}
+
+#endif /* CONFIG_PARAVIRT */
+
+#include <asm-generic/qspinlock.h>
+
+#endif // _ASM_LOONGARCH_QSPINLOCK_H