ACPICA: Re-implement interpreters' "serialized mode"

Enhanced the implementation of the interpreters'
serialized mode (boot with "acpi_serialize" to set
acpi_glb_all_methods_serialized flag.)
When this mode is specified, instead of creating a serialization
semaphore per control method, the interpreter lock is
simply no longer released before a blocking operation
during control method execution. This effectively makes
the AML Interpreter single-threaded. The overhead of a
semaphore per-method is eliminated.

Signed-off-by: Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 2 insertions, 9 deletions

diff --git a/drivers/acpi/namespace/nseval.c b/drivers/acpi/namespace/nseval.c
index 4b0a4a8c9843..71566161ac83 100644
--- a/drivers/acpi/namespace/nseval.c
+++ b/drivers/acpi/namespace/nseval.c
@@ -154,11 +154,7 @@ acpi_status acpi_ns_evaluate(struct acpi_evaluate_info *info)
                  * Execute the method via the interpreter. The interpreter is locked
                  * here before calling into the AML parser
                  */
-                status = acpi_ex_enter_interpreter();
-                if (ACPI_FAILURE(status)) {
-                        return_ACPI_STATUS(status);
-                }
-
+                acpi_ex_enter_interpreter();
                 status = acpi_ps_execute_method(info);
                 acpi_ex_exit_interpreter();
         } else {
@@ -182,10 +178,7 @@ acpi_status acpi_ns_evaluate(struct acpi_evaluate_info *info)
                  * resolution, we must lock it because we could access an opregion.
                  * The opregion access code assumes that the interpreter is locked.
                  */
-                status = acpi_ex_enter_interpreter();
-                if (ACPI_FAILURE(status)) {
-                        return_ACPI_STATUS(status);
-                }
+                acpi_ex_enter_interpreter();
 
                 /* Function has a strange interface */