ACPICA: DEBUG_PRINT macros: Update to improve performance.

Move check for "debug enable" to before the actual call to the
debug print routine. Improves time of ASLTS by about 15%.  Also,
remove "safe" exit macros since no complex expressions are ever
used in the return statements.

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 29 insertions, 3 deletions

diff --git a/include/acpi/acoutput.h b/include/acpi/acoutput.h
index 38e1be094655..be014bf7efe5 100644
--- a/include/acpi/acoutput.h
+++ b/include/acpi/acoutput.h
@@ -263,16 +263,42 @@
  * Common parameters used for debug output functions:
  * line number, function name, module(file) name, component ID
  */
-#define ACPI_DEBUG_PARAMETERS           __LINE__, ACPI_GET_FUNCTION_NAME, _acpi_module_name, _COMPONENT
+#define ACPI_DEBUG_PARAMETERS \
+        __LINE__, ACPI_GET_FUNCTION_NAME, _acpi_module_name, _COMPONENT
 
 /*
  * Master debug print macros
  * Print message if and only if:
  *    1) Debug print for the current component is enabled
  *    2) Debug error level or trace level for the print statement is enabled
+ *
+ * November 2012: Moved the runtime check for whether to actually emit the
+ * debug message outside of the print function itself. This improves overall
+ * performance at a relatively small code cost. Implementation involves the
+ * use of variadic macros supported by C99.
  */
-#define ACPI_DEBUG_PRINT(plist)         acpi_debug_print plist
-#define ACPI_DEBUG_PRINT_RAW(plist)     acpi_debug_print_raw plist
+
+/* DEBUG_PRINT functions */
+
+#define ACPI_DEBUG_PRINT(plist)         ACPI_ACTUAL_DEBUG plist
+#define ACPI_DEBUG_PRINT_RAW(plist)     ACPI_ACTUAL_DEBUG_RAW plist
+
+/* Helper macros for DEBUG_PRINT */
+
+#define ACPI_IS_DEBUG_ENABLED(level, component) \
+        (level & acpi_dbg_level) && (component & acpi_dbg_layer)
+
+#define ACPI_DEBUG(function, level, line, filename, modulename, component, ...) \
+        if (ACPI_IS_DEBUG_ENABLED (level, component)) \
+        { \
+                function (level, line, filename, modulename, component, __VA_ARGS__); \
+        }
+
+#define ACPI_ACTUAL_DEBUG(level, line, filename, modulename, component, ...) \
+        ACPI_DEBUG (acpi_debug_print, level, line, filename, modulename, component, __VA_ARGS__)
+
+#define ACPI_ACTUAL_DEBUG_RAW(level, line, filename, modulename, component, ...) \
+        ACPI_DEBUG (acpi_debug_print_raw, level, line, filename, modulename, component, __VA_ARGS__)
 
 #else
 /*