linux_dsm_epyc7002/drivers/acpi/acpica/utmutex.c
Lv Zheng f8d3148962 ACPICA: Debugger: Convert some mechanisms to OSPM specific
The following mechanisms are OSPM specific:
1. Redirect output destination to console: no file redirection will be
   needed by an in-kernel debugger, there is even no file can be accessed
   when the debugger is running in the kernel mode.
2. Output command prompts: programs other than acpiexec can have different
   prompt characters and the prompt characters may be implemented as a
   special character sequence to form a char device IO protocol.
3. Command ready/complete handshake: OSPM debugger may wait more conditions
   to implement OSPM specific semantics (for example, FIFO full/empty
   conditions for O_NONBLOCK or IO open/close conditions).
Leaving such OSPM specific stuffs in the ACPICA debugger core blocks
Linux debugger IO driver implementation.

Several new OSL APIs are provided by this patch:
1. acpi_os_initialize_command_signals: initialize command handshake mechanism
   or any other OSPM specific stuffs.
2. acpi_os_terminate_command_signals: reversal of
   acpi_os_initialize_command_signals.
3. acpi_os_wait_command_ready: putting debugger task into wait state when a
   command is not ready. OSPMs can terminate command loop by returning
   AE_CTRL_TERMINATE from this API. Normally, wait_event() or
   wait_for_multiple_object() may be used to implement this API.
4. acpi_os_notify_command_complete: putting user task into running state when a
   command has been completed. OSPMs can terminate command loop by
   returning AE_CTRL_TERMINATE from this API. Normally, wake_up() or
   set_event() may be used to implement this API.
This patch also converts current command signaling implementation into a
generic debugger layer (osgendbg.c) to be used by the existing OSPMs or
acpiexec, in return, Linux can have chance to implement its own command
handshake mechanism. This patch also implements acpiexec batch mode in a
multi-threading mode comaptible style as a demo (this can be confirmed by
configuring acpiexec into DEBUGGER_MULTI_THREADED mode where the batch mode
is still working). Lv Zheng.

Note that the OSPM specific command handshake mechanism is required by
Linux kernel because:
1. Linux kernel trends to use wait queue to synchronize two threads, using
   mutexes to achieve that will cause false "dead lock" warnings.
2. The command handshake mechanism implemented by ACPICA is implemented in
   this way because of a design issue in debugger IO streaming. Debugger IO
   outputs are simply cached using a giant buffer, this should be tuned by
   Linux in the future.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-15 00:17:43 +01:00

365 lines
10 KiB
C

/*******************************************************************************
*
* Module Name: utmutex - local mutex support
*
******************************************************************************/
/*
* Copyright (C) 2000 - 2015, 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"
#define _COMPONENT ACPI_UTILITIES
ACPI_MODULE_NAME("utmutex")
/* Local prototypes */
static acpi_status acpi_ut_create_mutex(acpi_mutex_handle mutex_id);
static void acpi_ut_delete_mutex(acpi_mutex_handle mutex_id);
/*******************************************************************************
*
* FUNCTION: acpi_ut_mutex_initialize
*
* PARAMETERS: None.
*
* RETURN: Status
*
* DESCRIPTION: Create the system mutex objects. This includes mutexes,
* spin locks, and reader/writer locks.
*
******************************************************************************/
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 < ACPI_NUM_MUTEX; i++) {
status = acpi_ut_create_mutex(i);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
}
/* Create the spinlocks for use at interrupt level or for speed */
status = acpi_os_create_lock (&acpi_gbl_gpe_lock);
if (ACPI_FAILURE (status)) {
return_ACPI_STATUS (status);
}
status = acpi_os_create_lock (&acpi_gbl_hardware_lock);
if (ACPI_FAILURE (status)) {
return_ACPI_STATUS (status);
}
status = acpi_os_create_lock(&acpi_gbl_reference_count_lock);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/* Mutex for _OSI support */
status = acpi_os_create_mutex(&acpi_gbl_osi_mutex);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/* Create the reader/writer lock for namespace access */
status = acpi_ut_create_rw_lock(&acpi_gbl_namespace_rw_lock);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_mutex_terminate
*
* PARAMETERS: None.
*
* RETURN: None.
*
* DESCRIPTION: Delete all of the system mutex objects. This includes mutexes,
* spin locks, and reader/writer locks.
*
******************************************************************************/
void acpi_ut_mutex_terminate(void)
{
u32 i;
ACPI_FUNCTION_TRACE(ut_mutex_terminate);
/* Delete each predefined mutex object */
for (i = 0; i < ACPI_NUM_MUTEX; i++) {
acpi_ut_delete_mutex(i);
}
acpi_os_delete_mutex(acpi_gbl_osi_mutex);
/* Delete the spinlocks */
acpi_os_delete_lock(acpi_gbl_gpe_lock);
acpi_os_delete_lock(acpi_gbl_hardware_lock);
acpi_os_delete_lock(acpi_gbl_reference_count_lock);
/* Delete the reader/writer lock */
acpi_ut_delete_rw_lock(&acpi_gbl_namespace_rw_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 (!acpi_gbl_mutex_info[mutex_id].mutex) {
status =
acpi_os_create_mutex(&acpi_gbl_mutex_info[mutex_id].mutex);
acpi_gbl_mutex_info[mutex_id].thread_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 void acpi_ut_delete_mutex(acpi_mutex_handle mutex_id)
{
ACPI_FUNCTION_TRACE_U32(ut_delete_mutex, mutex_id);
acpi_os_delete_mutex(acpi_gbl_mutex_info[mutex_id].mutex);
acpi_gbl_mutex_info[mutex_id].mutex = NULL;
acpi_gbl_mutex_info[mutex_id].thread_id = ACPI_MUTEX_NOT_ACQUIRED;
return_VOID;
}
/*******************************************************************************
*
* 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;
acpi_thread_id this_thread_id;
ACPI_FUNCTION_NAME(ut_acquire_mutex);
if (mutex_id > ACPI_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 < ACPI_NUM_MUTEX; i++) {
if (acpi_gbl_mutex_info[i].thread_id == this_thread_id) {
if (i == mutex_id) {
ACPI_ERROR((AE_INFO,
"Mutex [%s] already acquired by this thread [%u]",
acpi_ut_get_mutex_name
(mutex_id),
(u32)this_thread_id));
return (AE_ALREADY_ACQUIRED);
}
ACPI_ERROR((AE_INFO,
"Invalid acquire order: Thread %u owns [%s], wants [%s]",
(u32)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 %u attempting to acquire Mutex [%s]\n",
(u32)this_thread_id,
acpi_ut_get_mutex_name(mutex_id)));
status = acpi_os_acquire_mutex(acpi_gbl_mutex_info[mutex_id].mutex,
ACPI_WAIT_FOREVER);
if (ACPI_SUCCESS(status)) {
ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
"Thread %u acquired Mutex [%s]\n",
(u32)this_thread_id,
acpi_ut_get_mutex_name(mutex_id)));
acpi_gbl_mutex_info[mutex_id].use_count++;
acpi_gbl_mutex_info[mutex_id].thread_id = this_thread_id;
} else {
ACPI_EXCEPTION((AE_INFO, status,
"Thread %u could not acquire Mutex [0x%X]",
(u32)this_thread_id, mutex_id));
}
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_FUNCTION_NAME(ut_release_mutex);
ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Thread %u releasing Mutex [%s]\n",
(u32)acpi_os_get_thread_id(),
acpi_ut_get_mutex_name(mutex_id)));
if (mutex_id > ACPI_MAX_MUTEX) {
return (AE_BAD_PARAMETER);
}
/*
* Mutex must be acquired in order to release it!
*/
if (acpi_gbl_mutex_info[mutex_id].thread_id == ACPI_MUTEX_NOT_ACQUIRED) {
ACPI_ERROR((AE_INFO,
"Mutex [0x%X] is not acquired, cannot release",
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 < ACPI_NUM_MUTEX; i++) {
if (acpi_gbl_mutex_info[i].thread_id ==
acpi_os_get_thread_id()) {
if (i == mutex_id) {
continue;
}
ACPI_ERROR((AE_INFO,
"Invalid release order: owns [%s], releasing [%s]",
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].thread_id = ACPI_MUTEX_NOT_ACQUIRED;
acpi_os_release_mutex(acpi_gbl_mutex_info[mutex_id].mutex);
return (AE_OK);
}