LoongArch: Remove unnecessary checks for ORC unwinder

According to the following function definitions, __kernel_text_address()
already checks __module_text_address(), so it should remove the check of
__module_text_address() in bt_address() at least.

int __kernel_text_address(unsigned long addr)
{
	if (kernel_text_address(addr))
		return 1;
	...
	return 0;
}

int kernel_text_address(unsigned long addr)
{
	bool no_rcu;
	int ret = 1;
	...
	if (is_module_text_address(addr))
		goto out;
	...
	return ret;
}

bool is_module_text_address(unsigned long addr)
{
	guard(rcu)();
	return __module_text_address(addr) != NULL;
}

Furthermore, there are two checks of __kernel_text_address(), one is in
bt_address() and the other is after calling bt_address(), it looks like
redundant.

Handle the exception address first and then use __kernel_text_address()
to validate the calculated address for exception or the normal address
in bt_address(), then it can remove the check of __kernel_text_address()
after calling bt_address().

Just remove unnecessary checks, no functional changes intended.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

arch/loongarch/kernel/unwind_orc.c

@@ -352,12 +352,6 @@ static inline unsigned long bt_address(unsigned long ra)
 {
 	extern unsigned long eentry;
 
-	if (__kernel_text_address(ra))
-		return ra;
-
-	if (__module_text_address(ra))
-		return ra;
-
 	if (ra >= eentry && ra < eentry +  EXCCODE_INT_END * VECSIZE) {
 		unsigned long func;
 		unsigned long type = (ra - eentry) / VECSIZE;
@@ -375,10 +369,13 @@ static inline unsigned long bt_address(unsigned long ra)
 			break;
 		}
 
-		return func + offset;
+		ra = func + offset;
 	}
 
-	return ra;
+	if (__kernel_text_address(ra))
+		return ra;
+
+	return 0;
 }
 
 bool unwind_next_frame(struct unwind_state *state)
@@ -501,9 +498,6 @@ bool unwind_next_frame(struct unwind_state *state)
 		goto err;
 	}
 
-	if (!__kernel_text_address(state->pc))
-		goto err;
-
 	return true;
 
 err: