x86: msr-on-cpu: remove unnecessary level of abstraction

Remove an unnecessary level of abstraction in the msr-on-cpu library.
Although this duplicates some code, the duplicated code is less than
the additional code, and this way should be faster.

Additionally, change the order of the functions to make the regular
structure of this file more obvious.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

arch/x86/lib/msr-on-cpu.c

@@ -16,37 +16,46 @@ static void __rdmsr_on_cpu(void *info)
 	rdmsr(rv->msr_no, rv->l, rv->h);
 }
 
-static void __rdmsr_safe_on_cpu(void *info)
+static void __wrmsr_on_cpu(void *info)
 {
 	struct msr_info *rv = info;
 
-	rv->err = rdmsr_safe(rv->msr_no, &rv->l, &rv->h);
+	wrmsr(rv->msr_no, rv->l, rv->h);
 }
 
-static int _rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h, int safe)
+int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
 {
-	int err = 0;
+	int err;
 	struct msr_info rv;
 
 	rv.msr_no = msr_no;
-	if (safe) {
-		err = smp_call_function_single(cpu, __rdmsr_safe_on_cpu,
-					       &rv, 1);
-		err = err ? err : rv.err;
-	} else {
-		err = smp_call_function_single(cpu, __rdmsr_on_cpu, &rv, 1);
-	}
+	err = smp_call_function_single(cpu, __rdmsr_on_cpu, &rv, 1);
 	*l = rv.l;
 	*h = rv.h;
 
 	return err;
 }
 
-static void __wrmsr_on_cpu(void *info)
+int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
+{
+	int err;
+	struct msr_info rv;
+
+	rv.msr_no = msr_no;
+	rv.l = l;
+	rv.h = h;
+	err = smp_call_function_single(cpu, __wrmsr_on_cpu, &rv, 1);
+
+	return err;
+}
+
+/* These "safe" variants are slower and should be used when the target MSR
+   may not actually exist. */
+static void __rdmsr_safe_on_cpu(void *info)
 {
 	struct msr_info *rv = info;
 
-	wrmsr(rv->msr_no, rv->l, rv->h);
+	rv->err = rdmsr_safe(rv->msr_no, &rv->l, &rv->h);
 }
 
 static void __wrmsr_safe_on_cpu(void *info)
@@ -56,45 +65,30 @@ static void __wrmsr_safe_on_cpu(void *info)
 	rv->err = wrmsr_safe(rv->msr_no, rv->l, rv->h);
 }
 
-static int _wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h, int safe)
+int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
 {
-	int err = 0;
+	int err;
 	struct msr_info rv;
 
 	rv.msr_no = msr_no;
-	rv.l = l;
-	rv.h = h;
-	if (safe) {
-		err = smp_call_function_single(cpu, __wrmsr_safe_on_cpu,
-					       &rv, 1);
-		err = err ? err : rv.err;
-	} else {
-		err = smp_call_function_single(cpu, __wrmsr_on_cpu, &rv, 1);
-	}
-
-	return err;
-}
+	err = smp_call_function_single(cpu, __rdmsr_safe_on_cpu, &rv, 1);
+	*l = rv.l;
+	*h = rv.h;
 
-int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
-{
-	return _wrmsr_on_cpu(cpu, msr_no, l, h, 0);
+	return err ? err : rv.err;
 }
 
-int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
-{
-	return _rdmsr_on_cpu(cpu, msr_no, l, h, 0);
-}
-
-/* These "safe" variants are slower and should be used when the target MSR
-   may not actually exist. */
 int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
 {
-	return _wrmsr_on_cpu(cpu, msr_no, l, h, 1);
-}
+	int err;
+	struct msr_info rv;
 
-int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
-{
-	return _rdmsr_on_cpu(cpu, msr_no, l, h, 1);
+	rv.msr_no = msr_no;
+	rv.l = l;
+	rv.h = h;
+	err = smp_call_function_single(cpu, __wrmsr_safe_on_cpu, &rv, 1);
+
+	return err ? err : rv.err;
 }
 
 EXPORT_SYMBOL(rdmsr_on_cpu);