add r1, r1, r0, lsl #2 @ Get word offset
mov r3, r2, lsl r3 @ create mask
smp_dmb
+#if __LINUX_ARM_ARCH__ >= 7 && defined(CONFIG_SMP)
+ .arch_extension mp
+ ALT_SMP(W(pldw) [r1])
+ ALT_UP(W(nop))
+#endif
1: ldrex r2, [r1]
ands r0, r2, r3 @ save old value of bit
\instr r2, r2, r3 @ toggle bit