1 /*******************************************************************************
3 * Module Name: utmutex - local mutex support
5 ******************************************************************************/
8 * Copyright (C) 2000 - 2006, R. Byron Moore
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
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15 * notice, this list of conditions, and the following disclaimer,
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18 * substantially similar to the "NO WARRANTY" disclaimer below
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20 * including a substantially similar Disclaimer requirement for further
21 * binary redistribution.
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23 * of any contributors may be used to endorse or promote products derived
24 * from this software without specific prior written permission.
26 * Alternatively, this software may be distributed under the terms of the
27 * GNU General Public License ("GPL") version 2 as published by the Free
28 * Software Foundation.
31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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44 #include <acpi/acpi.h>
46 #define _COMPONENT ACPI_UTILITIES
47 ACPI_MODULE_NAME("utmutex")
49 /* Local prototypes */
50 static acpi_status acpi_ut_create_mutex(acpi_mutex_handle mutex_id);
52 static acpi_status acpi_ut_delete_mutex(acpi_mutex_handle mutex_id);
54 /*******************************************************************************
56 * FUNCTION: acpi_ut_mutex_initialize
62 * DESCRIPTION: Create the system mutex objects.
64 ******************************************************************************/
66 acpi_status acpi_ut_mutex_initialize(void)
71 ACPI_FUNCTION_TRACE("ut_mutex_initialize");
74 * Create each of the predefined mutex objects
76 for (i = 0; i < NUM_MUTEX; i++) {
77 status = acpi_ut_create_mutex(i);
78 if (ACPI_FAILURE(status)) {
79 return_ACPI_STATUS(status);
83 status = acpi_os_create_lock(&acpi_gbl_gpe_lock);
84 return_ACPI_STATUS(status);
87 /*******************************************************************************
89 * FUNCTION: acpi_ut_mutex_terminate
95 * DESCRIPTION: Delete all of the system mutex objects.
97 ******************************************************************************/
99 void acpi_ut_mutex_terminate(void)
103 ACPI_FUNCTION_TRACE("ut_mutex_terminate");
106 * Delete each predefined mutex object
108 for (i = 0; i < NUM_MUTEX; i++) {
109 (void)acpi_ut_delete_mutex(i);
112 acpi_os_delete_lock(acpi_gbl_gpe_lock);
116 /*******************************************************************************
118 * FUNCTION: acpi_ut_create_mutex
120 * PARAMETERS: mutex_iD - ID of the mutex to be created
124 * DESCRIPTION: Create a mutex object.
126 ******************************************************************************/
128 static acpi_status acpi_ut_create_mutex(acpi_mutex_handle mutex_id)
130 acpi_status status = AE_OK;
132 ACPI_FUNCTION_TRACE_U32("ut_create_mutex", mutex_id);
134 if (mutex_id > MAX_MUTEX) {
135 return_ACPI_STATUS(AE_BAD_PARAMETER);
138 if (!acpi_gbl_mutex_info[mutex_id].mutex) {
139 status = acpi_os_create_semaphore(1, 1,
142 acpi_gbl_mutex_info[mutex_id].thread_id =
143 ACPI_MUTEX_NOT_ACQUIRED;
144 acpi_gbl_mutex_info[mutex_id].use_count = 0;
147 return_ACPI_STATUS(status);
150 /*******************************************************************************
152 * FUNCTION: acpi_ut_delete_mutex
154 * PARAMETERS: mutex_iD - ID of the mutex to be deleted
158 * DESCRIPTION: Delete a mutex object.
160 ******************************************************************************/
162 static acpi_status acpi_ut_delete_mutex(acpi_mutex_handle mutex_id)
166 ACPI_FUNCTION_TRACE_U32("ut_delete_mutex", mutex_id);
168 if (mutex_id > MAX_MUTEX) {
169 return_ACPI_STATUS(AE_BAD_PARAMETER);
172 status = acpi_os_delete_semaphore(acpi_gbl_mutex_info[mutex_id].mutex);
174 acpi_gbl_mutex_info[mutex_id].mutex = NULL;
175 acpi_gbl_mutex_info[mutex_id].thread_id = ACPI_MUTEX_NOT_ACQUIRED;
177 return_ACPI_STATUS(status);
180 /*******************************************************************************
182 * FUNCTION: acpi_ut_acquire_mutex
184 * PARAMETERS: mutex_iD - ID of the mutex to be acquired
188 * DESCRIPTION: Acquire a mutex object.
190 ******************************************************************************/
192 acpi_status acpi_ut_acquire_mutex(acpi_mutex_handle mutex_id)
197 ACPI_FUNCTION_NAME("ut_acquire_mutex");
199 if (mutex_id > MAX_MUTEX) {
200 return (AE_BAD_PARAMETER);
203 this_thread_id = acpi_os_get_thread_id();
205 #ifdef ACPI_MUTEX_DEBUG
209 * Mutex debug code, for internal debugging only.
211 * Deadlock prevention. Check if this thread owns any mutexes of value
212 * greater than or equal to this one. If so, the thread has violated
213 * the mutex ordering rule. This indicates a coding error somewhere in
214 * the ACPI subsystem code.
216 for (i = mutex_id; i < MAX_MUTEX; i++) {
217 if (acpi_gbl_mutex_info[i].thread_id == this_thread_id) {
219 ACPI_REPORT_ERROR(("Mutex [%s] already acquired by this thread [%X]\n", acpi_ut_get_mutex_name(mutex_id), this_thread_id));
221 return (AE_ALREADY_ACQUIRED);
224 ACPI_REPORT_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)));
226 return (AE_ACQUIRE_DEADLOCK);
232 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
233 "Thread %X attempting to acquire Mutex [%s]\n",
234 this_thread_id, acpi_ut_get_mutex_name(mutex_id)));
236 status = acpi_os_wait_semaphore(acpi_gbl_mutex_info[mutex_id].mutex,
237 1, ACPI_WAIT_FOREVER);
238 if (ACPI_SUCCESS(status)) {
239 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
240 "Thread %X acquired Mutex [%s]\n",
242 acpi_ut_get_mutex_name(mutex_id)));
244 acpi_gbl_mutex_info[mutex_id].use_count++;
245 acpi_gbl_mutex_info[mutex_id].thread_id = this_thread_id;
247 ACPI_REPORT_ERROR(("Thread %X could not acquire Mutex [%X] %s\n", this_thread_id, mutex_id, acpi_format_exception(status)));
253 /*******************************************************************************
255 * FUNCTION: acpi_ut_release_mutex
257 * PARAMETERS: mutex_iD - ID of the mutex to be released
261 * DESCRIPTION: Release a mutex object.
263 ******************************************************************************/
265 acpi_status acpi_ut_release_mutex(acpi_mutex_handle mutex_id)
270 ACPI_FUNCTION_NAME("ut_release_mutex");
272 this_thread_id = acpi_os_get_thread_id();
273 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
274 "Thread %X releasing Mutex [%s]\n", this_thread_id,
275 acpi_ut_get_mutex_name(mutex_id)));
277 if (mutex_id > MAX_MUTEX) {
278 return (AE_BAD_PARAMETER);
282 * Mutex must be acquired in order to release it!
284 if (acpi_gbl_mutex_info[mutex_id].thread_id == ACPI_MUTEX_NOT_ACQUIRED) {
285 ACPI_REPORT_ERROR(("Mutex [%X] is not acquired, cannot release\n", mutex_id));
287 return (AE_NOT_ACQUIRED);
289 #ifdef ACPI_MUTEX_DEBUG
293 * Mutex debug code, for internal debugging only.
295 * Deadlock prevention. Check if this thread owns any mutexes of value
296 * greater than this one. If so, the thread has violated the mutex
297 * ordering rule. This indicates a coding error somewhere in
298 * the ACPI subsystem code.
300 for (i = mutex_id; i < MAX_MUTEX; i++) {
301 if (acpi_gbl_mutex_info[i].thread_id == this_thread_id) {
306 ACPI_REPORT_ERROR(("Invalid release order: owns [%s], releasing [%s]\n", acpi_ut_get_mutex_name(i), acpi_ut_get_mutex_name(mutex_id)));
308 return (AE_RELEASE_DEADLOCK);
314 /* Mark unlocked FIRST */
316 acpi_gbl_mutex_info[mutex_id].thread_id = ACPI_MUTEX_NOT_ACQUIRED;
319 acpi_os_signal_semaphore(acpi_gbl_mutex_info[mutex_id].mutex, 1);
321 if (ACPI_FAILURE(status)) {
322 ACPI_REPORT_ERROR(("Thread %X could not release Mutex [%X] %s\n", this_thread_id, mutex_id, acpi_format_exception(status)));
324 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
325 "Thread %X released Mutex [%s]\n",
327 acpi_ut_get_mutex_name(mutex_id)));