ACPI: processor: perflib: Rearrange acpi_processor_notify_smm()

Rearrange the code in acpi_processor_notify_smm() to consolidate error
handling in it and improve the comments in there while at it.

No expected functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/processor_perflib.c b/drivers/acpi/processor_perflib.c
index 10d2999a57737946296873a2272ee47baf665eff..7b6fa1b27afb7c7b27b61b40ef1093ab32e07432 100644 (file)
--- a/drivers/acpi/processor_perflib.c
+++ b/drivers/acpi/processor_perflib.c
@@ -453,7 +453,7 @@ int acpi_processor_pstate_control(void)
 int acpi_processor_notify_smm(struct module *calling_module)
 {
        static int is_done;
-       int result;
+       int result = 0;
 
        if (!acpi_processor_cpufreq_init)
                return -EBUSY;
@@ -461,40 +461,38 @@ int acpi_processor_notify_smm(struct module *calling_module)
        if (!try_module_get(calling_module))
                return -EINVAL;
 
-       /* is_done is set to negative if an error occurred,
-        * and to postitive if _no_ error occurred, but SMM
-        * was already notified. This avoids double notification
-        * which might lead to unexpected results...
+       /*
+        * is_done is set to negative if an error occurs and to 1 if no error
+        * occurrs, but SMM has been notified already. This avoids repeated
+        * notification which might lead to unexpected results.
         */
-       if (is_done > 0) {
-               module_put(calling_module);
-               return 0;
-       } else if (is_done < 0) {
-               module_put(calling_module);
-               return is_done;
-       }
+       if (is_done != 0) {
+               if (is_done < 0)
+                       result = is_done;
 
-       is_done = -EIO;
+               goto out_put;
+       }
 
        result = acpi_processor_pstate_control();
-       if (!result) {
-               pr_debug("No SMI port or pstate_control\n");
-               module_put(calling_module);
-               return 0;
-       }
-       if (result < 0) {
-               module_put(calling_module);
-               return result;
+       if (result <= 0) {
+               if (!result)
+                       pr_debug("No SMI port or pstate_control\n");
+
+               is_done = -EIO;
+               goto out_put;
        }
 
-       /* Success. If there's no _PPC, we need to fear nothing, so
-        * we can allow the cpufreq driver to be rmmod'ed. */
        is_done = 1;
+       /*
+        * Success. If there _PPC, unloading the cpufreq driver would be risky,
+        * so disallow it in that case.
+        */
+       if (acpi_processor_ppc_in_use)
+               return 0;
 
-       if (!acpi_processor_ppc_in_use)
-               module_put(calling_module);
-
-       return 0;
+out_put:
+       module_put(calling_module);
+       return result;
 }
 EXPORT_SYMBOL(acpi_processor_notify_smm);