/******************************************************************************
*
* Module Name: dsmethod - Parser/Interpreter interface - control method parsing
*
*****************************************************************************/
/*
* Copyright (C) 2000 - 2018, 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.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
AcpiDsDetectNamedOpcodes (
ACPI_WALK_STATE *WalkState,
ACPI_PARSE_OBJECT **OutOp);
static ACPI_STATUS
AcpiDsCreateMethodMutex (
ACPI_OPERAND_OBJECT *MethodDesc);
/*******************************************************************************
*
* FUNCTION: AcpiDsAutoSerializeMethod
*
* PARAMETERS: Node - Namespace Node of the method
* ObjDesc - 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
AcpiDsAutoSerializeMethod (
ACPI_NAMESPACE_NODE *Node,
ACPI_OPERAND_OBJECT *ObjDesc)
{
ACPI_STATUS Status;
ACPI_PARSE_OBJECT *Op = NULL;
ACPI_WALK_STATE *WalkState;
ACPI_FUNCTION_TRACE_PTR (DsAutoSerializeMethod, Node);
ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,
"Method auto-serialization parse [%4.4s] %p\n",
AcpiUtGetNodeName (Node), Node));
/* Create/Init a root op for the method parse tree */
Op = AcpiPsAllocOp (AML_METHOD_OP, ObjDesc->Method.AmlStart);
if (!Op)
{
return_ACPI_STATUS (AE_NO_MEMORY);
}
AcpiPsSetName (Op, Node->Name.Integer);
Op->Common.Node = Node;
/* Create and initialize a new walk state */
WalkState = AcpiDsCreateWalkState (Node->OwnerId, NULL, NULL, NULL);
if (!WalkState)
{
AcpiPsFreeOp (Op);
return_ACPI_STATUS (AE_NO_MEMORY);
}
Status = AcpiDsInitAmlWalk (WalkState, Op, Node,
ObjDesc->Method.AmlStart, ObjDesc->Method.AmlLength, NULL, 0);
if (ACPI_FAILURE (Status))
{
AcpiDsDeleteWalkState (WalkState);
AcpiPsFreeOp (Op);
return_ACPI_STATUS (Status);
}
WalkState->DescendingCallback = AcpiDsDetectNamedOpcodes;
/* Parse the method, scan for creation of named objects */
Status = AcpiPsParseAml (WalkState);
AcpiPsDeleteParseTree (Op);
return_ACPI_STATUS (Status);
}
/*******************************************************************************
*
* FUNCTION: AcpiDsDetectNamedOpcodes
*
* PARAMETERS: WalkState - Current state of the parse tree walk
* OutOp - 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
AcpiDsDetectNamedOpcodes (
ACPI_WALK_STATE *WalkState,
ACPI_PARSE_OBJECT **OutOp)
{
ACPI_FUNCTION_NAME (AcpiDsDetectNamedOpcodes);
/* We are only interested in opcodes that create a new name */
if (!(WalkState->OpInfo->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.
*/
WalkState->MethodDesc->Method.SyncLevel = 0;
WalkState->MethodDesc->Method.InfoFlags |=
(ACPI_METHOD_SERIALIZED | ACPI_METHOD_IGNORE_SYNC_LEVEL);
ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
"Method serialized [%4.4s] %p - [%s] (%4.4X)\n",
WalkState->MethodNode->Name.Ascii, WalkState->MethodNode,
WalkState->OpInfo->Name, WalkState->Opcode));
/* Abort the parse, no need to examine this method any further */
return (AE_CTRL_TERMINATE);
}
/*******************************************************************************
*
* FUNCTION: AcpiDsMethodError
*
* PARAMETERS: Status - Execution status
* WalkState - 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
AcpiDsMethodError (
ACPI_STATUS Status,
ACPI_WALK_STATE *WalkState)
{
UINT32 AmlOffset;
ACPI_NAME Name = 0;
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 (AcpiGbl_ExceptionHandler)
{
/* Exit the interpreter, allow handler to execute methods */
AcpiExExitInterpreter ();
/*
* Handler can map the exception code to anything it wants, including
* AE_OK, in which case the executing method will not be aborted.
*/
AmlOffset = (UINT32) ACPI_PTR_DIFF (WalkState->Aml,
WalkState->ParserState.AmlStart);
if (WalkState->MethodNode)
{
Name = WalkState->MethodNode->Name.Integer;
}
else if (WalkState->DeferredNode)
{
Name = WalkState->DeferredNode->Name.Integer;
}
Status = AcpiGbl_ExceptionHandler (Status, Name,
WalkState->Opcode, AmlOffset, NULL);
AcpiExEnterInterpreter ();
}
AcpiDsClearImplicitReturn (WalkState);
if (ACPI_FAILURE (Status))
{
AcpiDsDumpMethodStack (Status, WalkState, WalkState->Op);
/* Display method locals/args if debugger is present */
#ifdef ACPI_DEBUGGER
AcpiDbDumpMethodInfo (Status, WalkState);
#endif
}
return (Status);
}
/*******************************************************************************
*
* FUNCTION: AcpiDsCreateMethodMutex
*
* PARAMETERS: ObjDesc - The method object
*
* RETURN: Status
*
* DESCRIPTION: Create a mutex object for a serialized control method
*
******************************************************************************/
static ACPI_STATUS
AcpiDsCreateMethodMutex (
ACPI_OPERAND_OBJECT *MethodDesc)
{
ACPI_OPERAND_OBJECT *MutexDesc;
ACPI_STATUS Status;
ACPI_FUNCTION_TRACE (DsCreateMethodMutex);
/* Create the new mutex object */
MutexDesc = AcpiUtCreateInternalObject (ACPI_TYPE_MUTEX);
if (!MutexDesc)
{
return_ACPI_STATUS (AE_NO_MEMORY);
}
/* Create the actual OS Mutex */
Status = AcpiOsCreateMutex (&MutexDesc->Mutex.OsMutex);
if (ACPI_FAILURE (Status))
{
AcpiUtDeleteObjectDesc (MutexDesc);
return_ACPI_STATUS (Status);
}
MutexDesc->Mutex.SyncLevel = MethodDesc->Method.SyncLevel;
MethodDesc->Method.Mutex = MutexDesc;
return_ACPI_STATUS (AE_OK);
}
/*******************************************************************************
*
* FUNCTION: AcpiDsBeginMethodExecution
*
* PARAMETERS: MethodNode - Node of the method
* ObjDesc - The method object
* WalkState - 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
AcpiDsBeginMethodExecution (
ACPI_NAMESPACE_NODE *MethodNode,
ACPI_OPERAND_OBJECT *ObjDesc,
ACPI_WALK_STATE *WalkState)
{
ACPI_STATUS Status = AE_OK;
ACPI_FUNCTION_TRACE_PTR (DsBeginMethodExecution, MethodNode);
if (!MethodNode)
{
return_ACPI_STATUS (AE_NULL_ENTRY);
}
AcpiExStartTraceMethod (MethodNode, ObjDesc, WalkState);
/* Prevent wraparound of thread count */
if (ObjDesc->Method.ThreadCount == 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 (ObjDesc->Method.InfoFlags & 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 (!ObjDesc->Method.Mutex)
{
Status = AcpiDsCreateMethodMutex (ObjDesc);
if (ACPI_FAILURE (Status))
{
return_ACPI_STATUS (Status);
}
}
/*
* The CurrentSyncLevel (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 (WalkState &&
(!(ObjDesc->Method.InfoFlags & ACPI_METHOD_IGNORE_SYNC_LEVEL)) &&
(WalkState->Thread->CurrentSyncLevel >
ObjDesc->Method.Mutex->Mutex.SyncLevel))
{
ACPI_ERROR ((AE_INFO,
"Cannot acquire Mutex for method [%4.4s]"
", current SyncLevel is too large (%u)",
AcpiUtGetNodeName (MethodNode),
WalkState->Thread->CurrentSyncLevel));
return_ACPI_STATUS (AE_AML_MUTEX_ORDER);
}
/*
* Obtain the method mutex if necessary. Do not acquire mutex for a
* recursive call.
*/
if (!WalkState ||
!ObjDesc->Method.Mutex->Mutex.ThreadId ||
(WalkState->Thread->ThreadId !=
ObjDesc->Method.Mutex->Mutex.ThreadId))
{
/*
* Acquire the method mutex. This releases the interpreter if we
* block (and reacquires it before it returns)
*/
Status = AcpiExSystemWaitMutex (
ObjDesc->Method.Mutex->Mutex.OsMutex, ACPI_WAIT_FOREVER);
if (ACPI_FAILURE (Status))
{
return_ACPI_STATUS (Status);
}
/* Update the mutex and walk info and save the original SyncLevel */
if (WalkState)
{
ObjDesc->Method.Mutex->Mutex.OriginalSyncLevel =
WalkState->Thread->CurrentSyncLevel;
ObjDesc->Method.Mutex->Mutex.ThreadId =
WalkState->Thread->ThreadId;
/*
* Update the current SyncLevel 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 (!(ObjDesc->Method.InfoFlags &
ACPI_METHOD_IGNORE_SYNC_LEVEL))
{
WalkState->Thread->CurrentSyncLevel =
ObjDesc->Method.SyncLevel;
}
}
else
{
ObjDesc->Method.Mutex->Mutex.OriginalSyncLevel =
ObjDesc->Method.Mutex->Mutex.SyncLevel;
ObjDesc->Method.Mutex->Mutex.ThreadId =
AcpiOsGetThreadId ();
}
}
/* Always increase acquisition depth */
ObjDesc->Method.Mutex->Mutex.AcquisitionDepth++;
}
/*
* Allocate an Owner ID for this method, only if this is the first thread
* to begin concurrent execution. We only need one OwnerId, even if the
* method is invoked recursively.
*/
if (!ObjDesc->Method.OwnerId)
{
Status = AcpiUtAllocateOwnerId (&ObjDesc->Method.OwnerId);
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)
*/
ObjDesc->Method.ThreadCount++;
AcpiMethodCount++;
return_ACPI_STATUS (Status);
Cleanup:
/* On error, must release the method mutex (if present) */
if (ObjDesc->Method.Mutex)
{
AcpiOsReleaseMutex (ObjDesc->Method.Mutex->Mutex.OsMutex);
}
return_ACPI_STATUS (Status);
}
/*******************************************************************************
*
* FUNCTION: AcpiDsCallControlMethod
*
* PARAMETERS: Thread - Info for this thread
* ThisWalkState - Current walk state
* Op - Current Op to be walked
*
* RETURN: Status
*
* DESCRIPTION: Transfer execution to a called control method
*
******************************************************************************/
ACPI_STATUS
AcpiDsCallControlMethod (
ACPI_THREAD_STATE *Thread,
ACPI_WALK_STATE *ThisWalkState,
ACPI_PARSE_OBJECT *Op)
{
ACPI_STATUS Status;
ACPI_NAMESPACE_NODE *MethodNode;
ACPI_WALK_STATE *NextWalkState = NULL;
ACPI_OPERAND_OBJECT *ObjDesc;
ACPI_EVALUATE_INFO *Info;
UINT32 i;
ACPI_FUNCTION_TRACE_PTR (DsCallControlMethod, ThisWalkState);
ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
"Calling method %p, currentstate=%p\n",
ThisWalkState->PrevOp, ThisWalkState));
/*
* Get the namespace entry for the control method we are about to call
*/
MethodNode = ThisWalkState->MethodCallNode;
if (!MethodNode)
{
return_ACPI_STATUS (AE_NULL_ENTRY);
}
ObjDesc = AcpiNsGetAttachedObject (MethodNode);
if (!ObjDesc)
{
return_ACPI_STATUS (AE_NULL_OBJECT);
}
/* Init for new method, possibly wait on method mutex */
Status = AcpiDsBeginMethodExecution (
MethodNode, ObjDesc, ThisWalkState);
if (ACPI_FAILURE (Status))
{
return_ACPI_STATUS (Status);
}
/* Begin method parse/execution. Create a new walk state */
NextWalkState = AcpiDsCreateWalkState (
ObjDesc->Method.OwnerId, NULL, ObjDesc, Thread);
if (!NextWalkState)
{
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
*/
ThisWalkState->Operands [ThisWalkState->NumOperands] = NULL;
/*
* Allocate and initialize the evaluation information block
* TBD: this is somewhat inefficient, should change interface to
* DsInitAmlWalk. For now, keeps this struct off the CPU stack
*/
Info = ACPI_ALLOCATE_ZEROED (sizeof (ACPI_EVALUATE_INFO));
if (!Info)
{
Status = AE_NO_MEMORY;
goto Cleanup;
}
Info->Parameters = &ThisWalkState->Operands[0];
Status = AcpiDsInitAmlWalk (NextWalkState, NULL, MethodNode,
ObjDesc->Method.AmlStart, ObjDesc->Method.AmlLength,
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 < ObjDesc->Method.ParamCount; i++)
{
AcpiUtRemoveReference (ThisWalkState->Operands [i]);
ThisWalkState->Operands [i] = NULL;
}
/* Clear the operand stack */
ThisWalkState->NumOperands = 0;
ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
"**** Begin nested execution of [%4.4s] **** WalkState=%p\n",
MethodNode->Name.Ascii, NextWalkState));
/* Invoke an internal method if necessary */
if (ObjDesc->Method.InfoFlags & ACPI_METHOD_INTERNAL_ONLY)
{
Status = ObjDesc->Method.Dispatch.Implementation (NextWalkState);
if (Status == AE_OK)
{
Status = AE_CTRL_TERMINATE;
}
}
return_ACPI_STATUS (Status);
Cleanup:
/* On error, we must terminate the method properly */
AcpiDsTerminateControlMethod (ObjDesc, NextWalkState);
AcpiDsDeleteWalkState (NextWalkState);
return_ACPI_STATUS (Status);
}
/*******************************************************************************
*
* FUNCTION: AcpiDsRestartControlMethod
*
* PARAMETERS: WalkState - State for preempted method (caller)
* ReturnDesc - 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
AcpiDsRestartControlMethod (
ACPI_WALK_STATE *WalkState,
ACPI_OPERAND_OBJECT *ReturnDesc)
{
ACPI_STATUS Status;
int SameAsImplicitReturn;
ACPI_FUNCTION_TRACE_PTR (DsRestartControlMethod, WalkState);
ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
"****Restart [%4.4s] Op %p ReturnValueFromCallee %p\n",
AcpiUtGetNodeName (WalkState->MethodNode),
WalkState->MethodCallOp, ReturnDesc));
ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
" ReturnFromThisMethodUsed?=%X ResStack %p Walk %p\n",
WalkState->ReturnUsed,
WalkState->Results, WalkState));
/* Did the called method return a value? */
if (ReturnDesc)
{
/* Is the implicit return object the same as the return desc? */
SameAsImplicitReturn = (WalkState->ImplicitReturnObj == ReturnDesc);
/* Are we actually going to use the return value? */
if (WalkState->ReturnUsed)
{
/* Save the return value from the previous method */
Status = AcpiDsResultPush (ReturnDesc, WalkState);
if (ACPI_FAILURE (Status))
{
AcpiUtRemoveReference (ReturnDesc);
return_ACPI_STATUS (Status);
}
/*
* Save as THIS method's return value in case it is returned
* immediately to yet another method
*/
WalkState->ReturnDesc = ReturnDesc;
}
/*
* 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 (!AcpiDsDoImplicitReturn (ReturnDesc, WalkState, FALSE) ||
SameAsImplicitReturn)
{
/*
* 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.
*/
AcpiUtRemoveReference (ReturnDesc);
}
}
return_ACPI_STATUS (AE_OK);
}
/*******************************************************************************
*
* FUNCTION: AcpiDsTerminateControlMethod
*
* PARAMETERS: MethodDesc - Method object
* WalkState - 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
AcpiDsTerminateControlMethod (
ACPI_OPERAND_OBJECT *MethodDesc,
ACPI_WALK_STATE *WalkState)
{
ACPI_FUNCTION_TRACE_PTR (DsTerminateControlMethod, WalkState);
/* MethodDesc is required, WalkState is optional */
if (!MethodDesc)
{
return_VOID;
}
if (WalkState)
{
/* Delete all arguments and locals */
AcpiDsMethodDataDeleteAll (WalkState);
/*
* 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 (!(MethodDesc->Method.InfoFlags & ACPI_METHOD_MODULE_LEVEL) &&
(MethodDesc->Method.ThreadCount == 1))
{
/* Delete any direct children of (created by) this method */
(void) AcpiExExitInterpreter ();
AcpiNsDeleteNamespaceSubtree (WalkState->MethodNode);
(void) AcpiExEnterInterpreter ();
/*
* 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 (MethodDesc->Method.InfoFlags & ACPI_METHOD_MODIFIED_NAMESPACE)
{
(void) AcpiExExitInterpreter ();
AcpiNsDeleteNamespaceByOwner (MethodDesc->Method.OwnerId);
(void) AcpiExEnterInterpreter ();
MethodDesc->Method.InfoFlags &=
~ACPI_METHOD_MODIFIED_NAMESPACE;
}
}
/*
* If method is serialized, release the mutex and restore the
* current sync level for this thread
*/
if (MethodDesc->Method.Mutex)
{
/* Acquisition Depth handles recursive calls */
MethodDesc->Method.Mutex->Mutex.AcquisitionDepth--;
if (!MethodDesc->Method.Mutex->Mutex.AcquisitionDepth)
{
WalkState->Thread->CurrentSyncLevel =
MethodDesc->Method.Mutex->Mutex.OriginalSyncLevel;
AcpiOsReleaseMutex (
MethodDesc->Method.Mutex->Mutex.OsMutex);
MethodDesc->Method.Mutex->Mutex.ThreadId = 0;
}
}
}
/* Decrement the thread count on the method */
if (MethodDesc->Method.ThreadCount)
{
MethodDesc->Method.ThreadCount--;
}
else
{
ACPI_ERROR ((AE_INFO,
"Invalid zero thread count in method"));
}
/* Are there any other threads currently executing this method? */
if (MethodDesc->Method.ThreadCount)
{
/*
* Additional threads. Do not release the OwnerId 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",
MethodDesc->Method.ThreadCount));
}
else
{
/* This is the only executing thread for this method */
/*
* Support to dynamically change a method from NotSerialized 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 (MethodDesc->Method.InfoFlags & ACPI_METHOD_SERIALIZED_PENDING)
{
if (WalkState)
{
ACPI_INFO ((
"Marking method %4.4s as Serialized "
"because of AE_ALREADY_EXISTS error",
WalkState->MethodNode->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 NotSerialized, 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.
*/
MethodDesc->Method.InfoFlags &=
~ACPI_METHOD_SERIALIZED_PENDING;
MethodDesc->Method.InfoFlags |=
(ACPI_METHOD_SERIALIZED | ACPI_METHOD_IGNORE_SYNC_LEVEL);
MethodDesc->Method.SyncLevel = 0;
}
/* No more threads, we can free the OwnerId */
if (!(MethodDesc->Method.InfoFlags & ACPI_METHOD_MODULE_LEVEL))
{
AcpiUtReleaseOwnerId (&MethodDesc->Method.OwnerId);
}
}
AcpiExStopTraceMethod ((ACPI_NAMESPACE_NODE *) MethodDesc->Method.Node,
MethodDesc, WalkState);
return_VOID;
}