linux/drivers/acpi/acpica/dsmethod.c
Lv Zheng f5c1e1c5a6 ACPICA: Divergence: remove unwanted spaces for typedef
ACPICA commit b2294cae776f5a66a7697414b21949d307e6856f

This patch removes unwanted spaces for typedef. This solution doesn't cover
function types.

Note that the linuxize result of this commit is very giant and should have
many conflicts against the current Linux upstream. Thus it is required to
modify the linuxize result of this commit and the commits around it
manually in order to have them merged to the Linux upstream. Since this is
very costy, we should do this only once, and if we can't ensure to do this
only once, we need to revert the Linux code to the wrong indentation result
before merging the linuxize result of this commit. Lv Zheng.

Link: https://github.com/acpica/acpica/commit/b2294cae
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>
2016-05-05 15:14:35 +02:00

852 lines
26 KiB
C

/******************************************************************************
*
* Module Name: dsmethod - Parser/Interpreter interface - control method parsing
*
*****************************************************************************/
/*
* Copyright (C) 2000 - 2016, 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"
#include "acparser.h"
#include "amlcode.h"
#include "acdebug.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, obj_desc->method.aml_start);
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) {
acpi_ps_free_op(op);
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);
acpi_ps_free_op(op);
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);
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 debugger 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)
{
u32 aml_offset;
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.
*/
aml_offset = (u32)ACPI_PTR_DIFF(walk_state->aml,
walk_state->parser_state.
aml_start);
status = acpi_gbl_exception_handler(status,
walk_state->method_node ?
walk_state->method_node->
name.integer : 0,
walk_state->opcode,
aml_offset, NULL);
acpi_ex_enter_interpreter();
}
acpi_ds_clear_implicit_return(walk_state);
if (ACPI_FAILURE(status)) {
acpi_ds_dump_method_stack(status, walk_state, walk_state->op);
/* Display method locals/args if debugger is present */
#ifdef ACPI_DEBUGGER
acpi_db_dump_method_info(status, walk_state);
#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);
}
acpi_ex_start_trace_method(method_node, obj_desc, walk_state);
/* 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;
/*
* Update the current sync_level only if this is not an auto-
* serialized method. In the auto case, we have to ignore
* the sync level for the method mutex (created for the
* auto-serialization) because we have no idea of what the
* sync level should be. Therefore, just ignore it.
*/
if (!(obj_desc->method.info_flags &
ACPI_METHOD_IGNORE_SYNC_LEVEL)) {
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);
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(("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);
}
}
acpi_ex_stop_trace_method((struct acpi_namespace_node *)method_desc->
method.node, method_desc, walk_state);
return_VOID;
}