* recursive call.
                 */
                if (!walk_state ||
-                   !obj_desc->method.mutex->mutex.owner_thread ||
-                   (walk_state->thread !=
-                    obj_desc->method.mutex->mutex.owner_thread)) {
+                   !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)
                                    original_sync_level =
                                    walk_state->thread->current_sync_level;
 
-                               obj_desc->method.mutex->mutex.owner_thread =
-                                   walk_state->thread;
+                               obj_desc->method.mutex->mutex.thread_id =
+                                   walk_state->thread->thread_id;
                                walk_state->thread->current_sync_level =
                                    obj_desc->method.sync_level;
                        } else {
 
                        acpi_os_release_mutex(method_desc->method.mutex->mutex.
                                              os_mutex);
-                       method_desc->method.mutex->mutex.owner_thread = NULL;
+                       method_desc->method.mutex->mutex.thread_id = 0;
                }
        }
 
 
         * Only one thread can acquire the GL at a time, the global_lock_mutex
         * enforces this. This interface releases the interpreter if we must wait.
         */
-       status = acpi_ex_system_wait_mutex(acpi_gbl_global_lock_mutex, 0);
+       status = acpi_ex_system_wait_mutex(
+                       acpi_gbl_global_lock_mutex->mutex.os_mutex, 0);
        if (status == AE_TIME) {
                if (acpi_ev_global_lock_thread_id == acpi_os_get_thread_id()) {
                        acpi_ev_global_lock_acquired++;
        }
 
        if (ACPI_FAILURE(status)) {
-               status =
-                   acpi_ex_system_wait_mutex(acpi_gbl_global_lock_mutex,
-                                             timeout);
+               status = acpi_ex_system_wait_mutex(
+                               acpi_gbl_global_lock_mutex->mutex.os_mutex,
+                               timeout);
        }
        if (ACPI_FAILURE(status)) {
                return_ACPI_STATUS(status);
        /* Release the local GL mutex */
        acpi_ev_global_lock_thread_id = NULL;
        acpi_ev_global_lock_acquired = 0;
-       acpi_os_release_mutex(acpi_gbl_global_lock_mutex);
+       acpi_os_release_mutex(acpi_gbl_global_lock_mutex->mutex.os_mutex);
        return_ACPI_STATUS(status);
 }
 
 
  *
  * DESCRIPTION: Acquire the ACPI Global Lock
  *
+ * Note: Allows callers with the same thread ID to acquire the global lock
+ * multiple times. In other words, externally, the behavior of the global lock
+ * is identical to an AML mutex. On the first acquire, a new handle is
+ * returned. On any subsequent calls to acquire by the same thread, the same
+ * handle is returned.
+ *
  ******************************************************************************/
 acpi_status acpi_acquire_global_lock(u16 timeout, u32 * handle)
 {
        /* Must lock interpreter to prevent race conditions */
 
        acpi_ex_enter_interpreter();
-       status = acpi_ev_acquire_global_lock(timeout);
-       acpi_ex_exit_interpreter();
+
+       status = acpi_ex_acquire_mutex_object(timeout,
+                                             acpi_gbl_global_lock_mutex,
+                                             acpi_os_get_thread_id());
 
        if (ACPI_SUCCESS(status)) {
-               acpi_gbl_global_lock_handle++;
+               /*
+                * If this was the first acquisition of the Global Lock by this thread,
+                * create a new handle. Otherwise, return the existing handle.
+                */
+               if (acpi_gbl_global_lock_mutex->mutex.acquisition_depth == 1) {
+                       acpi_gbl_global_lock_handle++;
+               }
+
+               /* Return the global lock handle */
+
                *handle = acpi_gbl_global_lock_handle;
        }
 
+       acpi_ex_exit_interpreter();
        return (status);
 }
 
                return (AE_NOT_ACQUIRED);
        }
 
-       status = acpi_ev_release_global_lock();
+       status = acpi_ex_release_mutex_object(acpi_gbl_global_lock_mutex);
        return (status);
 }
 
 
        union acpi_operand_object *buffer_desc;
        acpi_size length;
        void *buffer;
-       u8 locked;
 
        ACPI_FUNCTION_TRACE_PTR(ex_read_data_from_field, obj_desc);
 
 
                /* Lock entire transaction if requested */
 
-               locked =
-                   acpi_ex_acquire_global_lock(obj_desc->common_field.
-                                               field_flags);
+               acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
 
                /*
                 * Perform the read.
                                                             buffer.pointer),
                                               ACPI_READ | (obj_desc->field.
                                                            attribute << 16));
-               acpi_ex_release_global_lock(locked);
+               acpi_ex_release_global_lock();
                goto exit;
        }
 
 
        /* Lock entire transaction if requested */
 
-       locked =
-           acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
+       acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
 
        /* Read from the field */
 
        status = acpi_ex_extract_from_field(obj_desc, buffer, (u32) length);
-       acpi_ex_release_global_lock(locked);
+       acpi_ex_release_global_lock();
 
       exit:
        if (ACPI_FAILURE(status)) {
        u32 required_length;
        void *buffer;
        void *new_buffer;
-       u8 locked;
        union acpi_operand_object *buffer_desc;
 
        ACPI_FUNCTION_TRACE_PTR(ex_write_data_to_field, obj_desc);
 
                /* Lock entire transaction if requested */
 
-               locked =
-                   acpi_ex_acquire_global_lock(obj_desc->common_field.
-                                               field_flags);
+               acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
 
                /*
                 * Perform the write (returns status and perhaps data in the
                                               (acpi_integer *) buffer,
                                               ACPI_WRITE | (obj_desc->field.
                                                             attribute << 16));
-               acpi_ex_release_global_lock(locked);
+               acpi_ex_release_global_lock();
 
                *result_desc = buffer_desc;
                return_ACPI_STATUS(status);
 
        /* Lock entire transaction if requested */
 
-       locked =
-           acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
+       acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
 
        /* Write to the field */
 
        status = acpi_ex_insert_into_field(obj_desc, buffer, length);
-       acpi_ex_release_global_lock(locked);
+       acpi_ex_release_global_lock();
 
        /* Free temporary buffer if we used one */
 
 
        thread->acquired_mutex_list = obj_desc;
 }
 
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ex_acquire_mutex_object
+ *
+ * PARAMETERS:  time_desc           - Timeout in milliseconds
+ *              obj_desc            - Mutex object
+ *              Thread              - Current thread state
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Acquire an AML mutex, low-level interface
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ex_acquire_mutex_object(u16 timeout,
+                            union acpi_operand_object *obj_desc,
+                            acpi_thread_id thread_id)
+{
+       acpi_status status;
+
+       ACPI_FUNCTION_TRACE_PTR(ex_acquire_mutex_object, obj_desc);
+
+       /* Support for multiple acquires by the owning thread */
+
+       if (obj_desc->mutex.thread_id == thread_id) {
+               /*
+                * The mutex is already owned by this thread, just increment the
+                * acquisition depth
+                */
+               obj_desc->mutex.acquisition_depth++;
+               return_ACPI_STATUS(AE_OK);
+       }
+
+       /* Acquire the mutex, wait if necessary. Special case for Global Lock */
+
+       if (obj_desc == acpi_gbl_global_lock_mutex) {
+               status = acpi_ev_acquire_global_lock(timeout);
+       } else {
+               status = acpi_ex_system_wait_mutex(obj_desc->mutex.os_mutex,
+                                                  timeout);
+       }
+
+       if (ACPI_FAILURE(status)) {
+
+               /* Includes failure from a timeout on time_desc */
+
+               return_ACPI_STATUS(status);
+       }
+
+       /* Have the mutex: update mutex and save the sync_level */
+
+       obj_desc->mutex.thread_id = thread_id;
+       obj_desc->mutex.acquisition_depth = 1;
+       obj_desc->mutex.original_sync_level = 0;
+       obj_desc->mutex.owner_thread = NULL;    /* Used only for AML Acquire() */
+
+       return_ACPI_STATUS(AE_OK);
+}
+
 /*******************************************************************************
  *
  * FUNCTION:    acpi_ex_acquire_mutex
        }
 
        /*
-        * Current Sync must be less than or equal to the sync level of the
+        * Current Sync level must be less than or equal to the sync level of the
         * mutex. This mechanism provides some deadlock prevention
         */
        if (walk_state->thread->current_sync_level > obj_desc->mutex.sync_level) {
                return_ACPI_STATUS(AE_AML_MUTEX_ORDER);
        }
 
-       /* Support for multiple acquires by the owning thread */
+       status = acpi_ex_acquire_mutex_object((u16) time_desc->integer.value,
+                                             obj_desc,
+                                             walk_state->thread->thread_id);
+       if (ACPI_SUCCESS(status) && obj_desc->mutex.acquisition_depth == 1) {
+               obj_desc->mutex.owner_thread = walk_state->thread;
+               obj_desc->mutex.original_sync_level =
+                   walk_state->thread->current_sync_level;
+               walk_state->thread->current_sync_level =
+                   obj_desc->mutex.sync_level;
 
-       if (obj_desc->mutex.owner_thread) {
-               if (obj_desc->mutex.owner_thread->thread_id ==
-                   walk_state->thread->thread_id) {
-                       /*
-                        * The mutex is already owned by this thread, just increment the
-                        * acquisition depth
-                        */
-                       obj_desc->mutex.acquisition_depth++;
-                       return_ACPI_STATUS(AE_OK);
-               }
+               /* Link the mutex to the current thread for force-unlock at method exit */
+
+               acpi_ex_link_mutex(obj_desc, walk_state->thread);
        }
 
-       /* Acquire the mutex, wait if necessary. Special case for Global Lock */
+       return_ACPI_STATUS(status);
+}
 
-       if (obj_desc->mutex.os_mutex == acpi_gbl_global_lock_mutex) {
-               status =
-                   acpi_ev_acquire_global_lock((u16) time_desc->integer.value);
-       } else {
-               status = acpi_ex_system_wait_mutex(obj_desc->mutex.os_mutex,
-                                                  (u16) time_desc->integer.
-                                                  value);
-       }
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ex_release_mutex_object
+ *
+ * PARAMETERS:  obj_desc            - The object descriptor for this op
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Release a previously acquired Mutex, low level interface.
+ *
+ ******************************************************************************/
 
-       if (ACPI_FAILURE(status)) {
+acpi_status acpi_ex_release_mutex_object(union acpi_operand_object *obj_desc)
+{
+       acpi_status status = AE_OK;
 
-               /* Includes failure from a timeout on time_desc */
+       ACPI_FUNCTION_TRACE(ex_release_mutex_object);
 
-               return_ACPI_STATUS(status);
+       /* Match multiple Acquires with multiple Releases */
+
+       obj_desc->mutex.acquisition_depth--;
+       if (obj_desc->mutex.acquisition_depth != 0) {
+
+               /* Just decrement the depth and return */
+
+               return_ACPI_STATUS(AE_OK);
        }
 
-       /* Have the mutex: update mutex and walk info and save the sync_level */
+       if (obj_desc->mutex.owner_thread) {
 
-       obj_desc->mutex.owner_thread = walk_state->thread;
-       obj_desc->mutex.acquisition_depth = 1;
-       obj_desc->mutex.original_sync_level =
-           walk_state->thread->current_sync_level;
+               /* Unlink the mutex from the owner's list */
+
+               acpi_ex_unlink_mutex(obj_desc);
+               obj_desc->mutex.owner_thread = NULL;
+       }
 
-       walk_state->thread->current_sync_level = obj_desc->mutex.sync_level;
+       /* Release the mutex, special case for Global Lock */
 
-       /* Link the mutex to the current thread for force-unlock at method exit */
+       if (obj_desc == acpi_gbl_global_lock_mutex) {
+               status = acpi_ev_release_global_lock();
+       } else {
+               acpi_os_release_mutex(obj_desc->mutex.os_mutex);
+       }
 
-       acpi_ex_link_mutex(obj_desc, walk_state->thread);
-       return_ACPI_STATUS(AE_OK);
+       obj_desc->mutex.thread_id = 0;
+       return_ACPI_STATUS(status);
 }
 
 /*******************************************************************************
                return_ACPI_STATUS(AE_AML_MUTEX_NOT_ACQUIRED);
        }
 
-       /* Sanity check: we must have a valid thread ID */
-
-       if (!walk_state->thread) {
-               ACPI_ERROR((AE_INFO,
-                           "Cannot release Mutex [%4.4s], null thread info",
-                           acpi_ut_get_node_name(obj_desc->mutex.node)));
-               return_ACPI_STATUS(AE_AML_INTERNAL);
-       }
-
        /*
         * The Mutex is owned, but this thread must be the owner.
         * Special case for Global Lock, any thread can release
         */
        if ((obj_desc->mutex.owner_thread->thread_id !=
             walk_state->thread->thread_id)
-           && (obj_desc->mutex.os_mutex != acpi_gbl_global_lock_mutex)) {
+           && (obj_desc != acpi_gbl_global_lock_mutex)) {
                ACPI_ERROR((AE_INFO,
                            "Thread %lX cannot release Mutex [%4.4s] acquired by thread %lX",
                            (unsigned long)walk_state->thread->thread_id,
                return_ACPI_STATUS(AE_AML_NOT_OWNER);
        }
 
+       /* Sanity check: we must have a valid thread ID */
+
+       if (!walk_state->thread) {
+               ACPI_ERROR((AE_INFO,
+                           "Cannot release Mutex [%4.4s], null thread info",
+                           acpi_ut_get_node_name(obj_desc->mutex.node)));
+               return_ACPI_STATUS(AE_AML_INTERNAL);
+       }
+
        /*
         * The sync level of the mutex must be less than or equal to the current
         * sync level
                return_ACPI_STATUS(AE_AML_MUTEX_ORDER);
        }
 
-       /* Match multiple Acquires with multiple Releases */
-
-       obj_desc->mutex.acquisition_depth--;
-       if (obj_desc->mutex.acquisition_depth != 0) {
-
-               /* Just decrement the depth and return */
-
-               return_ACPI_STATUS(AE_OK);
-       }
-
-       /* Unlink the mutex from the owner's list */
+       status = acpi_ex_release_mutex_object(obj_desc);
 
-       acpi_ex_unlink_mutex(obj_desc);
-
-       /* Release the mutex, special case for Global Lock */
+       /* Restore sync_level */
 
-       if (obj_desc->mutex.os_mutex == acpi_gbl_global_lock_mutex) {
-               status = acpi_ev_release_global_lock();
-       } else {
-               acpi_os_release_mutex(obj_desc->mutex.os_mutex);
-       }
-
-       /* Update the mutex and restore sync_level */
-
-       obj_desc->mutex.owner_thread = NULL;
        walk_state->thread->current_sync_level =
            obj_desc->mutex.original_sync_level;
-
        return_ACPI_STATUS(status);
 }
 
 
                /* Release the mutex, special case for Global Lock */
 
-               if (obj_desc->mutex.os_mutex == acpi_gbl_global_lock_mutex) {
+               if (obj_desc == acpi_gbl_global_lock_mutex) {
 
                        /* Ignore errors */
 
                /* Mark mutex unowned */
 
                obj_desc->mutex.owner_thread = NULL;
+               obj_desc->mutex.thread_id = 0;
 
                /* Update Thread sync_level (Last mutex is the important one) */
 
 
  * PARAMETERS:  field_flags           - Flags with Lock rule:
  *                                      always_lock or never_lock
  *
- * RETURN:      TRUE/FALSE indicating whether the lock was actually acquired
+ * RETURN:      None
  *
- * DESCRIPTION: Obtain the global lock and keep track of this fact via two
- *              methods.  A global variable keeps the state of the lock, and
- *              the state is returned to the caller.
+ * DESCRIPTION: Obtain the ACPI hardware Global Lock, only if the field
+ *              flags specifiy that it is to be obtained before field access.
  *
  ******************************************************************************/
 
-u8 acpi_ex_acquire_global_lock(u32 field_flags)
+void acpi_ex_acquire_global_lock(u32 field_flags)
 {
-       u8 locked = FALSE;
        acpi_status status;
 
        ACPI_FUNCTION_TRACE(ex_acquire_global_lock);
 
-       /* Only attempt lock if the always_lock bit is set */
+       /* Only use the lock if the always_lock bit is set */
+
+       if (!(field_flags & AML_FIELD_LOCK_RULE_MASK)) {
+               return_VOID;
+       }
 
-       if (field_flags & AML_FIELD_LOCK_RULE_MASK) {
+       /* Attempt to get the global lock, wait forever */
 
-               /* We should attempt to get the lock, wait forever */
+       status = acpi_ex_acquire_mutex_object(ACPI_WAIT_FOREVER,
+                                             acpi_gbl_global_lock_mutex,
+                                             acpi_os_get_thread_id());
 
-               status = acpi_ev_acquire_global_lock(ACPI_WAIT_FOREVER);
-               if (ACPI_SUCCESS(status)) {
-                       locked = TRUE;
-               } else {
-                       ACPI_EXCEPTION((AE_INFO, status,
-                                       "Could not acquire Global Lock"));
-               }
+       if (ACPI_FAILURE(status)) {
+               ACPI_EXCEPTION((AE_INFO, status,
+                               "Could not acquire Global Lock"));
        }
 
-       return_UINT8(locked);
+       return_VOID;
 }
 
 /*******************************************************************************
  *
  * FUNCTION:    acpi_ex_release_global_lock
  *
- * PARAMETERS:  locked_by_me    - Return value from corresponding call to
- *                                acquire_global_lock.
+ * PARAMETERS:  None
  *
  * RETURN:      None
  *
- * DESCRIPTION: Release the global lock if it is locked.
+ * DESCRIPTION: Release the ACPI hardware Global Lock
  *
  ******************************************************************************/
 
-void acpi_ex_release_global_lock(u8 locked_by_me)
+void acpi_ex_release_global_lock(void)
 {
        acpi_status status;
 
        ACPI_FUNCTION_TRACE(ex_release_global_lock);
 
-       /* Only attempt unlock if the caller locked it */
-
-       if (locked_by_me) {
+       /* Release the global lock */
 
-               /* OK, now release the lock */
-
-               status = acpi_ev_release_global_lock();
-               if (ACPI_FAILURE(status)) {
+       status = acpi_ex_release_mutex_object(acpi_gbl_global_lock_mutex);
+       if (ACPI_FAILURE(status)) {
 
-                       /* Report the error, but there isn't much else we can do */
+               /* Report the error, but there isn't much else we can do */
 
-                       ACPI_EXCEPTION((AE_INFO, status,
-                                       "Could not release ACPI Global Lock"));
-               }
+               ACPI_EXCEPTION((AE_INFO, status,
+                               "Could not release Global Lock"));
        }
 
        return_VOID;
 
                                /* Special case for ACPI Global Lock */
 
                                if (ACPI_STRCMP(init_val->name, "_GL_") == 0) {
-                                       acpi_gbl_global_lock_mutex =
-                                           obj_desc->mutex.os_mutex;
+                                       acpi_gbl_global_lock_mutex = obj_desc;
 
                                        /* Create additional counting semaphore for global lock */
 
 
                                  "***** Mutex %p, OS Mutex %p\n",
                                  object, object->mutex.os_mutex));
 
-               if (object->mutex.os_mutex == acpi_gbl_global_lock_mutex) {
+               if (object == acpi_gbl_global_lock_mutex) {
 
                        /* Global Lock has extra semaphore */
 
 
 ACPI_EXTERN struct acpi_mutex_info acpi_gbl_mutex_info[ACPI_NUM_MUTEX];
 
 /*
- * Global lock semaphore works in conjunction with the actual HW global lock
+ * Global lock mutex is an actual AML mutex object
+ * Global lock semaphore works in conjunction with the HW global lock
  */
-ACPI_EXTERN acpi_mutex acpi_gbl_global_lock_mutex;
+ACPI_EXTERN union acpi_operand_object *acpi_gbl_global_lock_mutex;
 ACPI_EXTERN acpi_semaphore acpi_gbl_global_lock_semaphore;
+ACPI_EXTERN u16 acpi_gbl_global_lock_handle;
+ACPI_EXTERN u8 acpi_gbl_global_lock_acquired;
+ACPI_EXTERN u8 acpi_gbl_global_lock_present;
 
 /*
  * Spinlocks are used for interfaces that can be possibly called at
 ACPI_EXTERN acpi_init_handler acpi_gbl_init_handler;
 ACPI_EXTERN struct acpi_walk_state *acpi_gbl_breakpoint_walk;
 
+/* Owner ID support */
+
+ACPI_EXTERN u32 acpi_gbl_owner_id_mask[ACPI_NUM_OWNERID_MASKS];
+ACPI_EXTERN u8 acpi_gbl_last_owner_id_index;
+ACPI_EXTERN u8 acpi_gbl_next_owner_id_offset;
+
 /* Misc */
 
 ACPI_EXTERN u32 acpi_gbl_original_mode;
 ACPI_EXTERN u32 acpi_gbl_rsdp_original_location;
 ACPI_EXTERN u32 acpi_gbl_ns_lookup_count;
 ACPI_EXTERN u32 acpi_gbl_ps_find_count;
-ACPI_EXTERN u32 acpi_gbl_owner_id_mask[ACPI_NUM_OWNERID_MASKS];
 ACPI_EXTERN u16 acpi_gbl_pm1_enable_register_save;
-ACPI_EXTERN u16 acpi_gbl_global_lock_handle;
-ACPI_EXTERN u8 acpi_gbl_last_owner_id_index;
-ACPI_EXTERN u8 acpi_gbl_next_owner_id_offset;
 ACPI_EXTERN u8 acpi_gbl_debugger_configuration;
-ACPI_EXTERN u8 acpi_gbl_global_lock_acquired;
 ACPI_EXTERN u8 acpi_gbl_step_to_next_call;
 ACPI_EXTERN u8 acpi_gbl_acpi_hardware_present;
-ACPI_EXTERN u8 acpi_gbl_global_lock_present;
 ACPI_EXTERN u8 acpi_gbl_events_initialized;
 ACPI_EXTERN u8 acpi_gbl_system_awake_and_running;
 
 
                      union acpi_operand_object *obj_desc,
                      struct acpi_walk_state *walk_state);
 
+acpi_status
+acpi_ex_acquire_mutex_object(u16 timeout,
+                            union acpi_operand_object *obj_desc,
+                            acpi_thread_id thread_id);
+
 acpi_status
 acpi_ex_release_mutex(union acpi_operand_object *obj_desc,
                      struct acpi_walk_state *walk_state);
 
+acpi_status acpi_ex_release_mutex_object(union acpi_operand_object *obj_desc);
+
 void acpi_ex_release_all_mutexes(struct acpi_thread_state *thread);
 
 void acpi_ex_unlink_mutex(union acpi_operand_object *obj_desc);
 
 void acpi_ex_truncate_for32bit_table(union acpi_operand_object *obj_desc);
 
-u8 acpi_ex_acquire_global_lock(u32 rule);
+void acpi_ex_acquire_global_lock(u32 rule);
 
-void acpi_ex_release_global_lock(u8 locked);
+void acpi_ex_release_global_lock(void);
 
 void acpi_ex_eisa_id_to_string(u32 numeric_id, char *out_string);
 
 
 struct acpi_object_mutex {
        ACPI_OBJECT_COMMON_HEADER u8 sync_level;        /* 0-15, specified in Mutex() call */
        u16 acquisition_depth;  /* Allow multiple Acquires, same thread */
-       struct acpi_thread_state *owner_thread; /* Current owner of the mutex */
        acpi_mutex os_mutex;    /* Actual OS synchronization object */
+       acpi_thread_id thread_id;       /* Current owner of the mutex */
+       struct acpi_thread_state *owner_thread; /* Current owner of the mutex */
        union acpi_operand_object *prev;        /* Link for list of acquired mutexes */
        union acpi_operand_object *next;        /* Link for list of acquired mutexes */
        struct acpi_namespace_node *node;       /* Containing namespace node */