kernel: locks: add spin lock/unlock function that don't change interrupt state

arch/x86_64/hwlock.S

@@ -11,6 +11,41 @@ ml_hwlock_lock:
 
 	mov $1, %ecx
 
+	mfence
+
+1:	mov $0, %eax
+	lock cmpxchg %ecx, (%rdi)
+	jne 1b
+
+	pop %rbp
+	ret
+
+
+	.global ml_hwlock_unlock
+	.type ml_hwlock_unlock, @function
+
+	/* %rdi = pointer to ml_hwlock_t (int) */
+ml_hwlock_unlock:
+	push %rbp
+	mov %rsp, %rbp
+
+	movl $0, (%rdi)
+	mfence
+
+	pop %rbp
+	ret
+
+
+	.global ml_hwlock_lock_irq
+	.type ml_hwlock_lock_irq, @function
+
+	/* %rdi = pointer to ml_hwlock_t (int) */
+ml_hwlock_lock_irq:
+	push %rbp
+	mov %rsp, %rbp
+
+	mov $1, %ecx
+
 	cli
 	mfence
 
@@ -21,11 +56,12 @@ ml_hwlock_lock:
 	pop %rbp
 	ret
 
-	.global ml_hwlock_unlock
-	.type ml_hwlock_unlock, @function
+
+	.global ml_hwlock_unlock_irq
+	.type ml_hwlock_unlock_irq, @function
 
 	/* %rdi = pointer to ml_hwlock_t (int) */
-ml_hwlock_unlock:
+ml_hwlock_unlock_irq:
 	push %rbp
 	mov %rsp, %rbp
 
@@ -42,7 +78,7 @@ ml_hwlock_unlock:
 
 	/* %rdi = pointer to ml_hwlock_t (int)
 	   %rsi = pointer to quadword to store rflags in */
-ml_hwlock_lock_irqsave:	
+ml_hwlock_lock_irqsave:
 	push %rbp
 	mov %rsp, %rbp
 
@@ -62,6 +98,7 @@ ml_hwlock_lock_irqsave:
 	pop %rbp
 	ret
 
+
 	.global ml_hwlock_unlock_irqrestore
 	.type ml_hwlock_unlock_irqrestore, @function