/*******************************************************************************
*
* Module Name: utmutex - local mutex support
*
******************************************************************************/
/*
* Copyright (C) 2000 - 2005, R. Byron Moore
* 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>
#define _COMPONENT ACPI_UTILITIES
ACPI_MODULE_NAME ("utmutex")
/* Local prototypes */
static acpi_status
acpi_ut_create_mutex (
acpi_mutex_handle mutex_id);
static acpi_status
acpi_ut_delete_mutex (
acpi_mutex_handle mutex_id);
/*******************************************************************************
*
* FUNCTION: acpi_ut_mutex_initialize
*
* PARAMETERS: None.
*
* RETURN: Status
*
* DESCRIPTION: Create the system mutex objects.
*
******************************************************************************/
acpi_status
acpi_ut_mutex_initialize (
void)
{
u32 i;
acpi_status status;
ACPI_FUNCTION_TRACE ("ut_mutex_initialize");
/*
* Create each of the predefined mutex objects
*/
for (i = 0; i < NUM_MUTEX; i++) {
status = acpi_ut_create_mutex (i);
if (ACPI_FAILURE (status)) {
return_ACPI_STATUS (status);
}
}
status = acpi_os_create_lock (&acpi_gbl_gpe_lock);
return_ACPI_STATUS (status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_mutex_terminate
*
* PARAMETERS: None.
*
* RETURN: None.
*
* DESCRIPTION: Delete all of the system mutex objects.
*
******************************************************************************/
void
acpi_ut_mutex_terminate (
void)
{
u32 i;
ACPI_FUNCTION_TRACE ("ut_mutex_terminate");
/*
* Delete each predefined mutex object
*/
for (i = 0; i < NUM_MUTEX; i++) {
(void) acpi_ut_delete_mutex (i);
}
acpi_os_delete_lock (acpi_gbl_gpe_lock);
return_VOID;
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_create_mutex
*
* PARAMETERS: mutex_iD - ID of the mutex to be created
*
* RETURN: Status
*
* DESCRIPTION: Create a mutex object.
*
******************************************************************************/
static acpi_status
acpi_ut_create_mutex (
acpi_mutex_handle mutex_id)
{
acpi_status status = AE_OK;
ACPI_FUNCTION_TRACE_U32 ("ut_create_mutex", mutex_id);
if (mutex_id > MAX_MUTEX) {
return_ACPI_STATUS (AE_BAD_PARAMETER);
}
if (!acpi_gbl_mutex_info[mutex_id].mutex) {
status = acpi_os_create_semaphore (1, 1,
&acpi_gbl_mutex_info[mutex_id].mutex);
acpi_gbl_mutex_info[mutex_id].owner_id = ACPI_MUTEX_NOT_ACQUIRED;
acpi_gbl_mutex_info[mutex_id].use_count = 0;
}
return_ACPI_STATUS (status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_delete_mutex
*
* PARAMETERS: mutex_iD - ID of the mutex to be deleted
*
* RETURN: Status
*
* DESCRIPTION: Delete a mutex object.
*
******************************************************************************/
static acpi_status
acpi_ut_delete_mutex (
acpi_mutex_handle mutex_id)
{
acpi_status status;
ACPI_FUNCTION_TRACE_U32 ("ut_delete_mutex", mutex_id);
if (mutex_id > MAX_MUTEX) {
return_ACPI_STATUS (AE_BAD_PARAMETER);
}
status = acpi_os_delete_semaphore (acpi_gbl_mutex_info[mutex_id].mutex);
acpi_gbl_mutex_info[mutex_id].mutex = NULL;
acpi_gbl_mutex_info[mutex_id].owner_id = ACPI_MUTEX_NOT_ACQUIRED;
return_ACPI_STATUS (status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_acquire_mutex
*
* PARAMETERS: mutex_iD - ID of the mutex to be acquired
*
* RETURN: Status
*
* DESCRIPTION: Acquire a mutex object.
*
******************************************************************************/
acpi_status
acpi_ut_acquire_mutex (
acpi_mutex_handle mutex_id)
{
acpi_status status;
u32 this_thread_id;
ACPI_FUNCTION_NAME ("ut_acquire_mutex");
if (mutex_id > MAX_MUTEX) {
return (AE_BAD_PARAMETER);
}
this_thread_id = acpi_os_get_thread_id ();
#ifdef ACPI_MUTEX_DEBUG
{
u32 i;
/*
* Mutex debug code, for internal debugging only.
*
* Deadlock prevention. Check if this thread owns any mutexes of value
* greater than or equal to this one. If so, the thread has violated
* the mutex ordering rule. This indicates a coding error somewhere in
* the ACPI subsystem code.
*/
for (i = mutex_id; i < MAX_MUTEX; i++) {
if (acpi_gbl_mutex_info[i].owner_id == this_thread_id) {
if (i == mutex_id) {
ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
"Mutex [%s] already acquired by this thread [%X]\n",
acpi_ut_get_mutex_name (mutex_id), this_thread_id));
return (AE_ALREADY_ACQUIRED);
}
ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
"Invalid acquire order: Thread %X owns [%s], wants [%s]\n",
this_thread_id, acpi_ut_get_mutex_name (i),
acpi_ut_get_mutex_name (mutex_id)));
return (AE_ACQUIRE_DEADLOCK);
}
}
}
#endif
ACPI_DEBUG_PRINT ((ACPI_DB_MUTEX,
"Thread %X attempting to acquire Mutex [%s]\n",
this_thread_id, acpi_ut_get_mutex_name (mutex_id)));
status = acpi_os_wait_semaphore (acpi_gbl_mutex_info[mutex_id].mutex,
1, ACPI_WAIT_FOREVER);
if (ACPI_SUCCESS (status)) {
ACPI_DEBUG_PRINT ((ACPI_DB_MUTEX, "Thread %X acquired Mutex [%s]\n",
this_thread_id, acpi_ut_get_mutex_name (mutex_id)));
acpi_gbl_mutex_info[mutex_id].use_count++;
acpi_gbl_mutex_info[mutex_id].owner_id = this_thread_id;
}
else {
ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
"Thread %X could not acquire Mutex [%s] %s\n",
this_thread_id, acpi_ut_get_mutex_name (mutex_id),
acpi_format_exception (status)));
}
return (status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_release_mutex
*
* PARAMETERS: mutex_iD - ID of the mutex to be released
*
* RETURN: Status
*
* DESCRIPTION: Release a mutex object.
*
******************************************************************************/
acpi_status
acpi_ut_release_mutex (
acpi_mutex_handle mutex_id)
{
acpi_status status;
u32 this_thread_id;
ACPI_FUNCTION_NAME ("ut_release_mutex");
this_thread_id = acpi_os_get_thread_id ();
ACPI_DEBUG_PRINT ((ACPI_DB_MUTEX,
"Thread %X releasing Mutex [%s]\n", this_thread_id,
acpi_ut_get_mutex_name (mutex_id)));
if (mutex_id > MAX_MUTEX) {
return (AE_BAD_PARAMETER);
}
/*
* Mutex must be acquired in order to release it!
*/
if (acpi_gbl_mutex_info[mutex_id].owner_id == ACPI_MUTEX_NOT_ACQUIRED) {
ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
"Mutex [%s] is not acquired, cannot release\n",
acpi_ut_get_mutex_name (mutex_id)));
return (AE_NOT_ACQUIRED);
}
#ifdef ACPI_MUTEX_DEBUG
{
u32 i;
/*
* Mutex debug code, for internal debugging only.
*
* Deadlock prevention. Check if this thread owns any mutexes of value
* greater than this one. If so, the thread has violated the mutex
* ordering rule. This indicates a coding error somewhere in
* the ACPI subsystem code.
*/
for (i = mutex_id; i < MAX_MUTEX; i++) {
if (acpi_gbl_mutex_info[i].owner_id == this_thread_id) {
if (i == mutex_id) {
continue;
}
ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
"Invalid release order: owns [%s], releasing [%s]\n",
acpi_ut_get_mutex_name (i), acpi_ut_get_mutex_name (mutex_id)));
return (AE_RELEASE_DEADLOCK);
}
}
}
#endif
/* Mark unlocked FIRST */
acpi_gbl_mutex_info[mutex_id].owner_id = ACPI_MUTEX_NOT_ACQUIRED;
status = acpi_os_signal_semaphore (acpi_gbl_mutex_info[mutex_id].mutex, 1);
if (ACPI_FAILURE (status)) {
ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
"Thread %X could not release Mutex [%s] %s\n",
this_thread_id, acpi_ut_get_mutex_name (mutex_id),
acpi_format_exception (status)));
}
else {
ACPI_DEBUG_PRINT ((ACPI_DB_MUTEX, "Thread %X released Mutex [%s]\n",
this_thread_id, acpi_ut_get_mutex_name (mutex_id)));
}
return (status);
}
