Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android

[firefly-linux-kernel-4.4.55.git] / arch / arm64 / include / asm / spinlock.h

diff --git a/arch/arm64/include/asm/spinlock.h b/arch/arm64/include/asm/spinlock.h
index 53ee219e76a735a8824df8b8b472ffb9febef29e..43a66881fd57c1b753639aee87958a6b347d4675 100644 (file)
--- a/arch/arm64/include/asm/spinlock.h
+++ b/arch/arm64/include/asm/spinlock.h
@@ -37,13 +37,17 @@ static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
 "2:    ldaxr   %w0, %2\n"
 "      eor     %w1, %w0, %w0, ror #16\n"
 "      cbnz    %w1, 1b\n"
+       /* Serialise against any concurrent lockers */
        ARM64_LSE_ATOMIC_INSN(
        /* LL/SC */
 "      stxr    %w1, %w0, %2\n"
-"      cbnz    %w1, 2b\n", /* Serialise against any concurrent lockers */
-       /* LSE atomics */
 "      nop\n"
-"      nop\n")
+"      nop\n",
+       /* LSE atomics */
+"      mov     %w1, %w0\n"
+"      cas     %w0, %w0, %2\n"
+"      eor     %w1, %w1, %w0\n")
+"      cbnz    %w1, 2b\n"
        : "=&r" (lockval), "=&r" (tmp), "+Q" (*lock)
        :
        : "memory");