Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / acpi / acpica / dsmethod.c
diff --git a/kernel/drivers/acpi/acpica/dsmethod.c b/kernel/drivers/acpi/acpica/dsmethod.c
new file mode 100644 (file)
index 0000000..d72565a
--- /dev/null
@@ -0,0 +1,831 @@
+/******************************************************************************
+ *
+ * Module Name: dsmethod - Parser/Interpreter interface - control method parsing
+ *
+ *****************************************************************************/
+
+/*
+ * Copyright (C) 2000 - 2015, Intel Corp.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions, and the following disclaimer,
+ *    without modification.
+ * 2. Redistributions in binary form must reproduce at minimum a disclaimer
+ *    substantially similar to the "NO WARRANTY" disclaimer below
+ *    ("Disclaimer") and any redistribution must be conditioned upon
+ *    including a substantially similar Disclaimer requirement for further
+ *    binary redistribution.
+ * 3. Neither the names of the above-listed copyright holders nor the names
+ *    of any contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * NO WARRANTY
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGES.
+ */
+
+#include <acpi/acpi.h>
+#include "accommon.h"
+#include "acdispat.h"
+#include "acinterp.h"
+#include "acnamesp.h"
+#ifdef ACPI_DISASSEMBLER
+#include "acdisasm.h"
+#endif
+#include "acparser.h"
+#include "amlcode.h"
+
+#define _COMPONENT          ACPI_DISPATCHER
+ACPI_MODULE_NAME("dsmethod")
+
+/* Local prototypes */
+static acpi_status
+acpi_ds_detect_named_opcodes(struct acpi_walk_state *walk_state,
+                            union acpi_parse_object **out_op);
+
+static acpi_status
+acpi_ds_create_method_mutex(union acpi_operand_object *method_desc);
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ds_auto_serialize_method
+ *
+ * PARAMETERS:  node                        - Namespace Node of the method
+ *              obj_desc                    - Method object attached to node
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Parse a control method AML to scan for control methods that
+ *              need serialization due to the creation of named objects.
+ *
+ * NOTE: It is a bit of overkill to mark all such methods serialized, since
+ * there is only a problem if the method actually blocks during execution.
+ * A blocking operation is, for example, a Sleep() operation, or any access
+ * to an operation region. However, it is probably not possible to easily
+ * detect whether a method will block or not, so we simply mark all suspicious
+ * methods as serialized.
+ *
+ * NOTE2: This code is essentially a generic routine for parsing a single
+ * control method.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ds_auto_serialize_method(struct acpi_namespace_node *node,
+                             union acpi_operand_object *obj_desc)
+{
+       acpi_status status;
+       union acpi_parse_object *op = NULL;
+       struct acpi_walk_state *walk_state;
+
+       ACPI_FUNCTION_TRACE_PTR(ds_auto_serialize_method, node);
+
+       ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
+                         "Method auto-serialization parse [%4.4s] %p\n",
+                         acpi_ut_get_node_name(node), node));
+
+       /* Create/Init a root op for the method parse tree */
+
+       op = acpi_ps_alloc_op(AML_METHOD_OP);
+       if (!op) {
+               return_ACPI_STATUS(AE_NO_MEMORY);
+       }
+
+       acpi_ps_set_name(op, node->name.integer);
+       op->common.node = node;
+
+       /* Create and initialize a new walk state */
+
+       walk_state =
+           acpi_ds_create_walk_state(node->owner_id, NULL, NULL, NULL);
+       if (!walk_state) {
+               return_ACPI_STATUS(AE_NO_MEMORY);
+       }
+
+       status =
+           acpi_ds_init_aml_walk(walk_state, op, node,
+                                 obj_desc->method.aml_start,
+                                 obj_desc->method.aml_length, NULL, 0);
+       if (ACPI_FAILURE(status)) {
+               acpi_ds_delete_walk_state(walk_state);
+               return_ACPI_STATUS(status);
+       }
+
+       walk_state->descending_callback = acpi_ds_detect_named_opcodes;
+
+       /* Parse the method, scan for creation of named objects */
+
+       status = acpi_ps_parse_aml(walk_state);
+       if (ACPI_FAILURE(status)) {
+               return_ACPI_STATUS(status);
+       }
+
+       acpi_ps_delete_parse_tree(op);
+       return_ACPI_STATUS(status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ds_detect_named_opcodes
+ *
+ * PARAMETERS:  walk_state      - Current state of the parse tree walk
+ *              out_op          - Unused, required for parser interface
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Descending callback used during the loading of ACPI tables.
+ *              Currently used to detect methods that must be marked serialized
+ *              in order to avoid problems with the creation of named objects.
+ *
+ ******************************************************************************/
+
+static acpi_status
+acpi_ds_detect_named_opcodes(struct acpi_walk_state *walk_state,
+                            union acpi_parse_object **out_op)
+{
+
+       ACPI_FUNCTION_NAME(acpi_ds_detect_named_opcodes);
+
+       /* We are only interested in opcodes that create a new name */
+
+       if (!
+           (walk_state->op_info->
+            flags & (AML_NAMED | AML_CREATE | AML_FIELD))) {
+               return (AE_OK);
+       }
+
+       /*
+        * At this point, we know we have a Named object opcode.
+        * Mark the method as serialized. Later code will create a mutex for
+        * this method to enforce serialization.
+        *
+        * Note, ACPI_METHOD_IGNORE_SYNC_LEVEL flag means that we will ignore the
+        * Sync Level mechanism for this method, even though it is now serialized.
+        * Otherwise, there can be conflicts with existing ASL code that actually
+        * uses sync levels.
+        */
+       walk_state->method_desc->method.sync_level = 0;
+       walk_state->method_desc->method.info_flags |=
+           (ACPI_METHOD_SERIALIZED | ACPI_METHOD_IGNORE_SYNC_LEVEL);
+
+       ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+                         "Method serialized [%4.4s] %p - [%s] (%4.4X)\n",
+                         walk_state->method_node->name.ascii,
+                         walk_state->method_node, walk_state->op_info->name,
+                         walk_state->opcode));
+
+       /* Abort the parse, no need to examine this method any further */
+
+       return (AE_CTRL_TERMINATE);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ds_method_error
+ *
+ * PARAMETERS:  status          - Execution status
+ *              walk_state      - Current state
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Called on method error. Invoke the global exception handler if
+ *              present, dump the method data if the disassembler is configured
+ *
+ *              Note: Allows the exception handler to change the status code
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ds_method_error(acpi_status status, struct acpi_walk_state * walk_state)
+{
+       ACPI_FUNCTION_ENTRY();
+
+       /* Ignore AE_OK and control exception codes */
+
+       if (ACPI_SUCCESS(status) || (status & AE_CODE_CONTROL)) {
+               return (status);
+       }
+
+       /* Invoke the global exception handler */
+
+       if (acpi_gbl_exception_handler) {
+
+               /* Exit the interpreter, allow handler to execute methods */
+
+               acpi_ex_exit_interpreter();
+
+               /*
+                * Handler can map the exception code to anything it wants, including
+                * AE_OK, in which case the executing method will not be aborted.
+                */
+               status = acpi_gbl_exception_handler(status,
+                                                   walk_state->method_node ?
+                                                   walk_state->method_node->
+                                                   name.integer : 0,
+                                                   walk_state->opcode,
+                                                   walk_state->aml_offset,
+                                                   NULL);
+               acpi_ex_enter_interpreter();
+       }
+
+       acpi_ds_clear_implicit_return(walk_state);
+
+#ifdef ACPI_DISASSEMBLER
+       if (ACPI_FAILURE(status)) {
+
+               /* Display method locals/args if disassembler is present */
+
+               acpi_dm_dump_method_info(status, walk_state, walk_state->op);
+       }
+#endif
+
+       return (status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ds_create_method_mutex
+ *
+ * PARAMETERS:  obj_desc            - The method object
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Create a mutex object for a serialized control method
+ *
+ ******************************************************************************/
+
+static acpi_status
+acpi_ds_create_method_mutex(union acpi_operand_object *method_desc)
+{
+       union acpi_operand_object *mutex_desc;
+       acpi_status status;
+
+       ACPI_FUNCTION_TRACE(ds_create_method_mutex);
+
+       /* Create the new mutex object */
+
+       mutex_desc = acpi_ut_create_internal_object(ACPI_TYPE_MUTEX);
+       if (!mutex_desc) {
+               return_ACPI_STATUS(AE_NO_MEMORY);
+       }
+
+       /* Create the actual OS Mutex */
+
+       status = acpi_os_create_mutex(&mutex_desc->mutex.os_mutex);
+       if (ACPI_FAILURE(status)) {
+               acpi_ut_delete_object_desc(mutex_desc);
+               return_ACPI_STATUS(status);
+       }
+
+       mutex_desc->mutex.sync_level = method_desc->method.sync_level;
+       method_desc->method.mutex = mutex_desc;
+       return_ACPI_STATUS(AE_OK);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ds_begin_method_execution
+ *
+ * PARAMETERS:  method_node         - Node of the method
+ *              obj_desc            - The method object
+ *              walk_state          - current state, NULL if not yet executing
+ *                                    a method.
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Prepare a method for execution. Parses the method if necessary,
+ *              increments the thread count, and waits at the method semaphore
+ *              for clearance to execute.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ds_begin_method_execution(struct acpi_namespace_node *method_node,
+                              union acpi_operand_object *obj_desc,
+                              struct acpi_walk_state *walk_state)
+{
+       acpi_status status = AE_OK;
+
+       ACPI_FUNCTION_TRACE_PTR(ds_begin_method_execution, method_node);
+
+       if (!method_node) {
+               return_ACPI_STATUS(AE_NULL_ENTRY);
+       }
+
+       /* Prevent wraparound of thread count */
+
+       if (obj_desc->method.thread_count == ACPI_UINT8_MAX) {
+               ACPI_ERROR((AE_INFO,
+                           "Method reached maximum reentrancy limit (255)"));
+               return_ACPI_STATUS(AE_AML_METHOD_LIMIT);
+       }
+
+       /*
+        * If this method is serialized, we need to acquire the method mutex.
+        */
+       if (obj_desc->method.info_flags & ACPI_METHOD_SERIALIZED) {
+               /*
+                * Create a mutex for the method if it is defined to be Serialized
+                * and a mutex has not already been created. We defer the mutex creation
+                * until a method is actually executed, to minimize the object count
+                */
+               if (!obj_desc->method.mutex) {
+                       status = acpi_ds_create_method_mutex(obj_desc);
+                       if (ACPI_FAILURE(status)) {
+                               return_ACPI_STATUS(status);
+                       }
+               }
+
+               /*
+                * The current_sync_level (per-thread) must be less than or equal to
+                * the sync level of the method. This mechanism provides some
+                * deadlock prevention.
+                *
+                * If the method was auto-serialized, we just ignore the sync level
+                * mechanism, because auto-serialization of methods can interfere
+                * with ASL code that actually uses sync levels.
+                *
+                * Top-level method invocation has no walk state at this point
+                */
+               if (walk_state &&
+                   (!(obj_desc->method.
+                      info_flags & ACPI_METHOD_IGNORE_SYNC_LEVEL))
+                   && (walk_state->thread->current_sync_level >
+                       obj_desc->method.mutex->mutex.sync_level)) {
+                       ACPI_ERROR((AE_INFO,
+                                   "Cannot acquire Mutex for method [%4.4s], current SyncLevel is too large (%u)",
+                                   acpi_ut_get_node_name(method_node),
+                                   walk_state->thread->current_sync_level));
+
+                       return_ACPI_STATUS(AE_AML_MUTEX_ORDER);
+               }
+
+               /*
+                * Obtain the method mutex if necessary. Do not acquire mutex for a
+                * recursive call.
+                */
+               if (!walk_state ||
+                   !obj_desc->method.mutex->mutex.thread_id ||
+                   (walk_state->thread->thread_id !=
+                    obj_desc->method.mutex->mutex.thread_id)) {
+                       /*
+                        * Acquire the method mutex. This releases the interpreter if we
+                        * block (and reacquires it before it returns)
+                        */
+                       status =
+                           acpi_ex_system_wait_mutex(obj_desc->method.mutex->
+                                                     mutex.os_mutex,
+                                                     ACPI_WAIT_FOREVER);
+                       if (ACPI_FAILURE(status)) {
+                               return_ACPI_STATUS(status);
+                       }
+
+                       /* Update the mutex and walk info and save the original sync_level */
+
+                       if (walk_state) {
+                               obj_desc->method.mutex->mutex.
+                                   original_sync_level =
+                                   walk_state->thread->current_sync_level;
+
+                               obj_desc->method.mutex->mutex.thread_id =
+                                   walk_state->thread->thread_id;
+                               walk_state->thread->current_sync_level =
+                                   obj_desc->method.sync_level;
+                       } else {
+                               obj_desc->method.mutex->mutex.
+                                   original_sync_level =
+                                   obj_desc->method.mutex->mutex.sync_level;
+                       }
+               }
+
+               /* Always increase acquisition depth */
+
+               obj_desc->method.mutex->mutex.acquisition_depth++;
+       }
+
+       /*
+        * Allocate an Owner ID for this method, only if this is the first thread
+        * to begin concurrent execution. We only need one owner_id, even if the
+        * method is invoked recursively.
+        */
+       if (!obj_desc->method.owner_id) {
+               status = acpi_ut_allocate_owner_id(&obj_desc->method.owner_id);
+               if (ACPI_FAILURE(status)) {
+                       goto cleanup;
+               }
+       }
+
+       /*
+        * Increment the method parse tree thread count since it has been
+        * reentered one more time (even if it is the same thread)
+        */
+       obj_desc->method.thread_count++;
+       acpi_method_count++;
+       return_ACPI_STATUS(status);
+
+cleanup:
+       /* On error, must release the method mutex (if present) */
+
+       if (obj_desc->method.mutex) {
+               acpi_os_release_mutex(obj_desc->method.mutex->mutex.os_mutex);
+       }
+       return_ACPI_STATUS(status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ds_call_control_method
+ *
+ * PARAMETERS:  thread              - Info for this thread
+ *              this_walk_state     - Current walk state
+ *              op                  - Current Op to be walked
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Transfer execution to a called control method
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ds_call_control_method(struct acpi_thread_state *thread,
+                           struct acpi_walk_state *this_walk_state,
+                           union acpi_parse_object *op)
+{
+       acpi_status status;
+       struct acpi_namespace_node *method_node;
+       struct acpi_walk_state *next_walk_state = NULL;
+       union acpi_operand_object *obj_desc;
+       struct acpi_evaluate_info *info;
+       u32 i;
+
+       ACPI_FUNCTION_TRACE_PTR(ds_call_control_method, this_walk_state);
+
+       ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+                         "Calling method %p, currentstate=%p\n",
+                         this_walk_state->prev_op, this_walk_state));
+
+       /*
+        * Get the namespace entry for the control method we are about to call
+        */
+       method_node = this_walk_state->method_call_node;
+       if (!method_node) {
+               return_ACPI_STATUS(AE_NULL_ENTRY);
+       }
+
+       obj_desc = acpi_ns_get_attached_object(method_node);
+       if (!obj_desc) {
+               return_ACPI_STATUS(AE_NULL_OBJECT);
+       }
+
+       /* Init for new method, possibly wait on method mutex */
+
+       status = acpi_ds_begin_method_execution(method_node, obj_desc,
+                                               this_walk_state);
+       if (ACPI_FAILURE(status)) {
+               return_ACPI_STATUS(status);
+       }
+
+       /* Begin method parse/execution. Create a new walk state */
+
+       next_walk_state = acpi_ds_create_walk_state(obj_desc->method.owner_id,
+                                                   NULL, obj_desc, thread);
+       if (!next_walk_state) {
+               status = AE_NO_MEMORY;
+               goto cleanup;
+       }
+
+       /*
+        * The resolved arguments were put on the previous walk state's operand
+        * stack. Operands on the previous walk state stack always
+        * start at index 0. Also, null terminate the list of arguments
+        */
+       this_walk_state->operands[this_walk_state->num_operands] = NULL;
+
+       /*
+        * Allocate and initialize the evaluation information block
+        * TBD: this is somewhat inefficient, should change interface to
+        * ds_init_aml_walk. For now, keeps this struct off the CPU stack
+        */
+       info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
+       if (!info) {
+               status = AE_NO_MEMORY;
+               goto cleanup;
+       }
+
+       info->parameters = &this_walk_state->operands[0];
+
+       status = acpi_ds_init_aml_walk(next_walk_state, NULL, method_node,
+                                      obj_desc->method.aml_start,
+                                      obj_desc->method.aml_length, info,
+                                      ACPI_IMODE_EXECUTE);
+
+       ACPI_FREE(info);
+       if (ACPI_FAILURE(status)) {
+               goto cleanup;
+       }
+
+       /*
+        * Delete the operands on the previous walkstate operand stack
+        * (they were copied to new objects)
+        */
+       for (i = 0; i < obj_desc->method.param_count; i++) {
+               acpi_ut_remove_reference(this_walk_state->operands[i]);
+               this_walk_state->operands[i] = NULL;
+       }
+
+       /* Clear the operand stack */
+
+       this_walk_state->num_operands = 0;
+
+       ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+                         "**** Begin nested execution of [%4.4s] **** WalkState=%p\n",
+                         method_node->name.ascii, next_walk_state));
+
+       /* Invoke an internal method if necessary */
+
+       if (obj_desc->method.info_flags & ACPI_METHOD_INTERNAL_ONLY) {
+               status =
+                   obj_desc->method.dispatch.implementation(next_walk_state);
+               if (status == AE_OK) {
+                       status = AE_CTRL_TERMINATE;
+               }
+       }
+
+       return_ACPI_STATUS(status);
+
+cleanup:
+
+       /* On error, we must terminate the method properly */
+
+       acpi_ds_terminate_control_method(obj_desc, next_walk_state);
+       if (next_walk_state) {
+               acpi_ds_delete_walk_state(next_walk_state);
+       }
+
+       return_ACPI_STATUS(status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ds_restart_control_method
+ *
+ * PARAMETERS:  walk_state          - State for preempted method (caller)
+ *              return_desc         - Return value from the called method
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Restart a method that was preempted by another (nested) method
+ *              invocation. Handle the return value (if any) from the callee.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ds_restart_control_method(struct acpi_walk_state *walk_state,
+                              union acpi_operand_object *return_desc)
+{
+       acpi_status status;
+       int same_as_implicit_return;
+
+       ACPI_FUNCTION_TRACE_PTR(ds_restart_control_method, walk_state);
+
+       ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+                         "****Restart [%4.4s] Op %p ReturnValueFromCallee %p\n",
+                         acpi_ut_get_node_name(walk_state->method_node),
+                         walk_state->method_call_op, return_desc));
+
+       ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+                         "    ReturnFromThisMethodUsed?=%X ResStack %p Walk %p\n",
+                         walk_state->return_used,
+                         walk_state->results, walk_state));
+
+       /* Did the called method return a value? */
+
+       if (return_desc) {
+
+               /* Is the implicit return object the same as the return desc? */
+
+               same_as_implicit_return =
+                   (walk_state->implicit_return_obj == return_desc);
+
+               /* Are we actually going to use the return value? */
+
+               if (walk_state->return_used) {
+
+                       /* Save the return value from the previous method */
+
+                       status = acpi_ds_result_push(return_desc, walk_state);
+                       if (ACPI_FAILURE(status)) {
+                               acpi_ut_remove_reference(return_desc);
+                               return_ACPI_STATUS(status);
+                       }
+
+                       /*
+                        * Save as THIS method's return value in case it is returned
+                        * immediately to yet another method
+                        */
+                       walk_state->return_desc = return_desc;
+               }
+
+               /*
+                * The following code is the optional support for the so-called
+                * "implicit return". Some AML code assumes that the last value of the
+                * method is "implicitly" returned to the caller, in the absence of an
+                * explicit return value.
+                *
+                * Just save the last result of the method as the return value.
+                *
+                * NOTE: this is optional because the ASL language does not actually
+                * support this behavior.
+                */
+               else if (!acpi_ds_do_implicit_return
+                        (return_desc, walk_state, FALSE)
+                        || same_as_implicit_return) {
+                       /*
+                        * Delete the return value if it will not be used by the
+                        * calling method or remove one reference if the explicit return
+                        * is the same as the implicit return value.
+                        */
+                       acpi_ut_remove_reference(return_desc);
+               }
+       }
+
+       return_ACPI_STATUS(AE_OK);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ds_terminate_control_method
+ *
+ * PARAMETERS:  method_desc         - Method object
+ *              walk_state          - State associated with the method
+ *
+ * RETURN:      None
+ *
+ * DESCRIPTION: Terminate a control method. Delete everything that the method
+ *              created, delete all locals and arguments, and delete the parse
+ *              tree if requested.
+ *
+ * MUTEX:       Interpreter is locked
+ *
+ ******************************************************************************/
+
+void
+acpi_ds_terminate_control_method(union acpi_operand_object *method_desc,
+                                struct acpi_walk_state *walk_state)
+{
+
+       ACPI_FUNCTION_TRACE_PTR(ds_terminate_control_method, walk_state);
+
+       /* method_desc is required, walk_state is optional */
+
+       if (!method_desc) {
+               return_VOID;
+       }
+
+       if (walk_state) {
+
+               /* Delete all arguments and locals */
+
+               acpi_ds_method_data_delete_all(walk_state);
+
+               /*
+                * If method is serialized, release the mutex and restore the
+                * current sync level for this thread
+                */
+               if (method_desc->method.mutex) {
+
+                       /* Acquisition Depth handles recursive calls */
+
+                       method_desc->method.mutex->mutex.acquisition_depth--;
+                       if (!method_desc->method.mutex->mutex.acquisition_depth) {
+                               walk_state->thread->current_sync_level =
+                                   method_desc->method.mutex->mutex.
+                                   original_sync_level;
+
+                               acpi_os_release_mutex(method_desc->method.
+                                                     mutex->mutex.os_mutex);
+                               method_desc->method.mutex->mutex.thread_id = 0;
+                       }
+               }
+
+               /*
+                * Delete any namespace objects created anywhere within the
+                * namespace by the execution of this method. Unless:
+                * 1) This method is a module-level executable code method, in which
+                *    case we want make the objects permanent.
+                * 2) There are other threads executing the method, in which case we
+                *    will wait until the last thread has completed.
+                */
+               if (!(method_desc->method.info_flags & ACPI_METHOD_MODULE_LEVEL)
+                   && (method_desc->method.thread_count == 1)) {
+
+                       /* Delete any direct children of (created by) this method */
+
+                       acpi_ns_delete_namespace_subtree(walk_state->
+                                                        method_node);
+
+                       /*
+                        * Delete any objects that were created by this method
+                        * elsewhere in the namespace (if any were created).
+                        * Use of the ACPI_METHOD_MODIFIED_NAMESPACE optimizes the
+                        * deletion such that we don't have to perform an entire
+                        * namespace walk for every control method execution.
+                        */
+                       if (method_desc->method.
+                           info_flags & ACPI_METHOD_MODIFIED_NAMESPACE) {
+                               acpi_ns_delete_namespace_by_owner(method_desc->
+                                                                 method.
+                                                                 owner_id);
+                               method_desc->method.info_flags &=
+                                   ~ACPI_METHOD_MODIFIED_NAMESPACE;
+                       }
+               }
+       }
+
+       /* Decrement the thread count on the method */
+
+       if (method_desc->method.thread_count) {
+               method_desc->method.thread_count--;
+       } else {
+               ACPI_ERROR((AE_INFO, "Invalid zero thread count in method"));
+       }
+
+       /* Are there any other threads currently executing this method? */
+
+       if (method_desc->method.thread_count) {
+               /*
+                * Additional threads. Do not release the owner_id in this case,
+                * we immediately reuse it for the next thread executing this method
+                */
+               ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+                                 "*** Completed execution of one thread, %u threads remaining\n",
+                                 method_desc->method.thread_count));
+       } else {
+               /* This is the only executing thread for this method */
+
+               /*
+                * Support to dynamically change a method from not_serialized to
+                * Serialized if it appears that the method is incorrectly written and
+                * does not support multiple thread execution. The best example of this
+                * is if such a method creates namespace objects and blocks. A second
+                * thread will fail with an AE_ALREADY_EXISTS exception.
+                *
+                * This code is here because we must wait until the last thread exits
+                * before marking the method as serialized.
+                */
+               if (method_desc->method.
+                   info_flags & ACPI_METHOD_SERIALIZED_PENDING) {
+                       if (walk_state) {
+                               ACPI_INFO((AE_INFO,
+                                          "Marking method %4.4s as Serialized because of AE_ALREADY_EXISTS error",
+                                          walk_state->method_node->name.
+                                          ascii));
+                       }
+
+                       /*
+                        * Method tried to create an object twice and was marked as
+                        * "pending serialized". The probable cause is that the method
+                        * cannot handle reentrancy.
+                        *
+                        * The method was created as not_serialized, but it tried to create
+                        * a named object and then blocked, causing the second thread
+                        * entrance to begin and then fail. Workaround this problem by
+                        * marking the method permanently as Serialized when the last
+                        * thread exits here.
+                        */
+                       method_desc->method.info_flags &=
+                           ~ACPI_METHOD_SERIALIZED_PENDING;
+                       method_desc->method.info_flags |=
+                           (ACPI_METHOD_SERIALIZED |
+                            ACPI_METHOD_IGNORE_SYNC_LEVEL);
+                       method_desc->method.sync_level = 0;
+               }
+
+               /* No more threads, we can free the owner_id */
+
+               if (!
+                   (method_desc->method.
+                    info_flags & ACPI_METHOD_MODULE_LEVEL)) {
+                       acpi_ut_release_owner_id(&method_desc->method.owner_id);
+               }
+       }
+
+       return_VOID;
+}