ACPICA: Remove global option to serialize all control methods.

According to the reports, the "acpi_serialize" mechanism is broken as:

 A. The parallel method calls can still happen when the interpreter lock is
    released under the following conditions:
    1. External callbacks are invoked, for example, by the region handlers,
       the exception handlers, etc.;
    2. Module level execution is performed when Load/LoadTable opcodes are
       executed, and
    3. The _REG control methods are invoked to complete the region
       registrations.
 B. For the following situations, the interpreter lock need to be released
    even for a serialized method while currently, the lock-releasing
    operation is marked as a no-op by
    acpi_ex_relinquish/reacquire_interpreter() when this mechanism is
    enabled:
    1. Wait opcode is executed,
    2. Acquire opcode is executed, and
    3. Sleep opcode is executed.

This patch removes this mechanism and the internal
acpi_ex_relinquish/reacquire_interpreter() APIs.  Lv Zheng.

References: https://bugzilla.kernel.org/show_bug.cgi?id=52191
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 10 insertions, 70 deletions

diff --git a/drivers/acpi/acpica/exutils.c b/drivers/acpi/acpica/exutils.c
index 5b16c5484bee..d9d72dff2a76 100644
--- a/drivers/acpi/acpica/exutils.c
+++ b/drivers/acpi/acpica/exutils.c
@@ -100,37 +100,6 @@ void acpi_ex_enter_interpreter(void)
 
 /*******************************************************************************
  *
- * FUNCTION:    acpi_ex_reacquire_interpreter
- *
- * PARAMETERS:  None
- *
- * RETURN:      None
- *
- * DESCRIPTION: Reacquire the interpreter execution region from within the
- *              interpreter code. Failure to enter the interpreter region is a
- *              fatal system error. Used in conjunction with
- *              relinquish_interpreter
- *
- ******************************************************************************/
-
-void acpi_ex_reacquire_interpreter(void)
-{
-	ACPI_FUNCTION_TRACE(ex_reacquire_interpreter);
-
-	/*
-	 * If the global serialized flag is set, do not release the interpreter,
-	 * since it was not actually released by acpi_ex_relinquish_interpreter.
-	 * This forces the interpreter to be single threaded.
-	 */
-	if (!acpi_gbl_all_methods_serialized) {
-		acpi_ex_enter_interpreter();
-	}
-
-	return_VOID;
-}
-
-/*******************************************************************************
- *
  * FUNCTION:    acpi_ex_exit_interpreter
  *
  * PARAMETERS:  None
@@ -139,7 +108,16 @@ void acpi_ex_reacquire_interpreter(void)
  *
  * DESCRIPTION: Exit the interpreter execution region. This is the top level
  *              routine used to exit the interpreter when all processing has
- *              been completed.
+ *              been completed, or when the method blocks.
+ *
+ * Cases where the interpreter is unlocked internally:
+ *      1) Method will be blocked on a Sleep() AML opcode
+ *      2) Method will be blocked on an Acquire() AML opcode
+ *      3) Method will be blocked on a Wait() AML opcode
+ *      4) Method will be blocked to acquire the global lock
+ *      5) Method will be blocked waiting to execute a serialized control
+ *          method that is currently executing
+ *      6) About to invoke a user-installed opregion handler
  *
  ******************************************************************************/
 
@@ -160,44 +138,6 @@ void acpi_ex_exit_interpreter(void)
 
 /*******************************************************************************
  *
- * FUNCTION:    acpi_ex_relinquish_interpreter
- *
- * PARAMETERS:  None
- *
- * RETURN:      None
- *
- * DESCRIPTION: Exit the interpreter execution region, from within the
- *              interpreter - before attempting an operation that will possibly
- *              block the running thread.
- *
- * Cases where the interpreter is unlocked internally
- *      1) Method to be blocked on a Sleep() AML opcode
- *      2) Method to be blocked on an Acquire() AML opcode
- *      3) Method to be blocked on a Wait() AML opcode
- *      4) Method to be blocked to acquire the global lock
- *      5) Method to be blocked waiting to execute a serialized control method
- *          that is currently executing
- *      6) About to invoke a user-installed opregion handler
- *
- ******************************************************************************/
-
-void acpi_ex_relinquish_interpreter(void)
-{
-	ACPI_FUNCTION_TRACE(ex_relinquish_interpreter);
-
-	/*
-	 * If the global serialized flag is set, do not release the interpreter.
-	 * This forces the interpreter to be single threaded.
-	 */
-	if (!acpi_gbl_all_methods_serialized) {
-		acpi_ex_exit_interpreter();
-	}
-
-	return_VOID;
-}
-
-/*******************************************************************************
- *
  * FUNCTION:    acpi_ex_truncate_for32bit_table
  *
  * PARAMETERS:  obj_desc        - Object to be truncated