diff --git a/libc/arch-arm/bionic/atomics_arm.S b/libc/arch-arm/bionic/atomics_arm.S
index b2da09f..57c4239 100644
--- a/libc/arch-arm/bionic/atomics_arm.S
+++ b/libc/arch-arm/bionic/atomics_arm.S
@@ -129,8 +129,18 @@
 #endif
 
 /* r0(new) r1(addr) -> r0(old) */
+/* replaced swp instruction with ldrex/strex for ARMv6 & ARMv7 */
 __atomic_swap:
+#if defined (_ARM_HAVE_LDREX_STREX)
+1:  ldrex   r2, [r1]
+    strex   r3, r0, [r1]
+    teq     r3, #0
+    bne     1b
+    mov     r0, r2
+    mcr     p15, 0, r0, c7, c10, 5 /* or, use dmb */
+#else
     swp     r0, r0, [r1]
+#endif
     bx      lr
 
 /* __futex_wait(*ftx, val, *timespec) */