ACPI: utils: Rearrange in acpi_evaluate_reference()

The code in acpi_evaluate_reference() can be improved in some ways
without changing its observable behavior.  Among other things:

 * None of the local variables in that function except for buffer
   needs to be initialized.

 * The element local variable is only used in the for () loop block,
   so it can be defined there.

 * Multiple checks can be combined.

 * Code duplication related to error handling can be eliminated.

 * Redundant inner parens can be dropped.

Modify the function as per the above.

No intentional functional impact.

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

diff --git a/drivers/acpi/utils.c b/drivers/acpi/utils.c
index 3dbc5ee..5a7766c 100644 (file)
--- a/drivers/acpi/utils.c
+++ b/drivers/acpi/utils.c
@@ -335,12 +335,10 @@ acpi_evaluate_reference(acpi_handle handle,
                        struct acpi_object_list *arguments,
                        struct acpi_handle_list *list)
 {
-       acpi_status status = AE_OK;
-       union acpi_object *package = NULL;
-       union acpi_object *element = NULL;
        struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
-       u32 i = 0;
-
+       union acpi_object *package;
+       acpi_status status;
+       u32 i;
 
        if (!list)
                return AE_BAD_PARAMETER;
@@ -353,45 +351,32 @@ acpi_evaluate_reference(acpi_handle handle,
 
        package = buffer.pointer;
 
-       if ((buffer.length == 0) || !package) {
-               status = AE_BAD_DATA;
-               acpi_util_eval_error(handle, pathname, status);
-               goto end;
-       }
-       if (package->type != ACPI_TYPE_PACKAGE) {
+       if (buffer.length == 0 || !package ||
+           package->type != ACPI_TYPE_PACKAGE || !package->package.count) {
                status = AE_BAD_DATA;
-               acpi_util_eval_error(handle, pathname, status);
-               goto end;
-       }
-       if (!package->package.count) {
-               status = AE_BAD_DATA;
-               acpi_util_eval_error(handle, pathname, status);
-               goto end;
+               goto err;
        }
 
-       list->handles = kcalloc(package->package.count, sizeof(*list->handles), GFP_KERNEL);
+       list->count = package->package.count;
+       list->handles = kcalloc(list->count, sizeof(*list->handles), GFP_KERNEL);
        if (!list->handles) {
-               kfree(package);
-               return AE_NO_MEMORY;
+               status = AE_NO_MEMORY;
+               goto err_clear;
        }
-       list->count = package->package.count;
 
        /* Extract package data. */
 
        for (i = 0; i < list->count; i++) {
-
-               element = &(package->package.elements[i]);
+               union acpi_object *element = &(package->package.elements[i]);
 
                if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
                        status = AE_BAD_DATA;
-                       acpi_util_eval_error(handle, pathname, status);
-                       break;
+                       goto err_free;
                }
 
                if (!element->reference.handle) {
                        status = AE_NULL_ENTRY;
-                       acpi_util_eval_error(handle, pathname, status);
-                       break;
+                       goto err_free;
                }
                /* Get the  acpi_handle. */
 
@@ -399,16 +384,21 @@ acpi_evaluate_reference(acpi_handle handle,
                acpi_handle_debug(list->handles[i], "Found in reference list\n");
        }
 
-       if (ACPI_FAILURE(status)) {
-               list->count = 0;
-               kfree(list->handles);
-               list->handles = NULL;
-       }
-
 end:
        kfree(buffer.pointer);
 
        return status;
+
+err_free:
+       kfree(list->handles);
+       list->handles = NULL;
+
+err_clear:
+       list->count = 0;
+
+err:
+       acpi_util_eval_error(handle, pathname, status);
+       goto end;
 }
 
 EXPORT_SYMBOL(acpi_evaluate_reference);