1 files changed, 21 insertions, 11 deletions
diff --git a/lib/libc/internal/include/atomic.h b/lib/libc/internal/include/atomic.h
index e0593021..d40c1eae 100644
--- a/lib/libc/internal/include/atomic.h
+++ b/lib/libc/internal/include/atomic.h
@@ -1,22 +1,32 @@
 #ifndef __LIBC_ATOMIC_H
 #define __LIBC_ATOMIC_H
 
+#include <libc/futex.h>
+#include <sched.h>
 #include <stdatomic.h>
+#include <unistd.h>
 
 #define LIBC_LOCK(__lock)   __libc_lock(&((__lock)))
-#define LIBC_UNLOCK(__lock) atomic_flag_clear(&((__lock)))
+#define LIBC_UNLOCK(__lock) __libc_unlock(&((__lock)))
 
-static __inline void __libc_lock(volatile atomic_flag *lock)
+__attribute__((__always_inline__)) __inline void __libc_unlock(volatile atomic_flag *lock)
 {
-	while (atomic_flag_test_and_set_explicit(lock, memory_order_acquire)) {
-		unsigned int spins = 1;
-		do {
-			for (unsigned int i = 0; i < spins; i++)
-				__asm__ volatile("pause");
-			if (spins < 64)
-				spins *= 2;
-		} while (atomic_flag_test_and_set_explicit(
-			lock, memory_order_relaxed));
+	atomic_flag_clear_explicit(lock, memory_order_release);
+	__futex_wake((volatile int *)lock, 1);
+}
+
+__attribute__((__always_inline__)) __inline void __libc_lock(volatile atomic_flag *lock)
+{
+	if (atomic_flag_test_and_set_explicit(lock, memory_order_acquire) == 0)
+		return;
+
+	while (1) {
+		__futex_wait((volatile int *)lock, 1);
+
+		if (atomic_flag_test_and_set_explicit(lock, memory_order_acquire) == 0)
+			return;
+
+		sched_yield();
 	}
 }