[PATCH 1/2] ACPI / ACPICA: refactor acpi_evaluate_object() to reduce nesting if

From: Hanjun Guo
Date: Fri Jan 24 2014 - 11:20:51 EST


acpi_evaluate_object() has nesting if judgement to make code a little
bit complicated, refactor it to make things simple.

Signed-off-by: Hanjun Guo <hanjun.guo@xxxxxxxxxx>
---
drivers/acpi/acpica/nsxfeval.c | 104 +++++++++++++++++++---------------------
1 file changed, 50 insertions(+), 54 deletions(-)

diff --git a/drivers/acpi/acpica/nsxfeval.c b/drivers/acpi/acpica/nsxfeval.c
index 1f0c28b..a1b0b88 100644
--- a/drivers/acpi/acpica/nsxfeval.c
+++ b/drivers/acpi/acpica/nsxfeval.c
@@ -370,68 +370,64 @@ acpi_evaluate_object(acpi_handle handle,
* If we are expecting a return value, and all went well above,
* copy the return value to an external object.
*/
- if (return_buffer) {
- if (!info->return_object) {
- return_buffer->length = 0;
- } else {
- if (ACPI_GET_DESCRIPTOR_TYPE(info->return_object) ==
- ACPI_DESC_TYPE_NAMED) {
- /*
- * If we received a NS Node as a return object, this means that
- * the object we are evaluating has nothing interesting to
- * return (such as a mutex, etc.) We return an error because
- * these types are essentially unsupported by this interface.
- * We don't check up front because this makes it easier to add
- * support for various types at a later date if necessary.
- */
- status = AE_TYPE;
- info->return_object = NULL; /* No need to delete a NS Node */
- return_buffer->length = 0;
- }
+ if (!return_buffer)
+ goto out;

- if (ACPI_SUCCESS(status)) {
+ if (!info->return_object) {
+ return_buffer->length = 0;
+ goto out;
+ }

- /* Dereference Index and ref_of references */
+ if (ACPI_GET_DESCRIPTOR_TYPE(info->return_object) ==
+ ACPI_DESC_TYPE_NAMED) {
+ /*
+ * If we received a NS Node as a return object, this means that
+ * the object we are evaluating has nothing interesting to
+ * return (such as a mutex, etc.) We return an error because
+ * these types are essentially unsupported by this interface.
+ * We don't check up front because this makes it easier to add
+ * support for various types at a later date if necessary.
+ */
+ status = AE_TYPE;
+ info->return_object = NULL; /* No need to delete a NS Node */
+ return_buffer->length = 0;
+ }

- acpi_ns_resolve_references(info);
+ if (ACPI_FAILURE(status))
+ goto out;

- /* Get the size of the returned object */
+ /* Dereference Index and ref_of references */

- status =
- acpi_ut_get_object_size(info->return_object,
- &buffer_space_needed);
- if (ACPI_SUCCESS(status)) {
-
- /* Validate/Allocate/Clear caller buffer */
-
- status =
- acpi_ut_initialize_buffer
- (return_buffer,
- buffer_space_needed);
- if (ACPI_FAILURE(status)) {
- /*
- * Caller's buffer is too small or a new one can't
- * be allocated
- */
- ACPI_DEBUG_PRINT((ACPI_DB_INFO,
- "Needed buffer size %X, %s\n",
- (u32)
- buffer_space_needed,
- acpi_format_exception
- (status)));
- } else {
- /* We have enough space for the object, build it */
-
- status =
- acpi_ut_copy_iobject_to_eobject
- (info->return_object,
- return_buffer);
- }
- }
- }
+ acpi_ns_resolve_references(info);
+
+ /* Get the size of the returned object */
+
+ status = acpi_ut_get_object_size(info->return_object,
+ &buffer_space_needed);
+ if (ACPI_SUCCESS(status)) {
+
+ /* Validate/Allocate/Clear caller buffer */
+
+ status = acpi_ut_initialize_buffer(return_buffer,
+ buffer_space_needed);
+ if (ACPI_FAILURE(status)) {
+ /*
+ * Caller's buffer is too small or a new one can't
+ * be allocated
+ */
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "Needed buffer size %X, %s\n",
+ (u32)buffer_space_needed,
+ acpi_format_exception(status)));
+ } else {
+ /* We have enough space for the object, build it */
+
+ status = acpi_ut_copy_iobject_to_eobject(
+ info->return_object, return_buffer);
}
}

+out:
if (info->return_object) {
/*
* Delete the internal return object. NOTE: Interpreter must be
--
1.7.9.5

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