linux/drivers/acpi/utilities/utcache.c
Robert Moore f9f4601f33 ACPICA 20050708 from Bob Moore <robert.moore@intel.com>
The use of the CPU stack in the debug version of the
subsystem has been considerably reduced.  Previously, a
debug structure was declared in every function that used
the debug macros.  This structure has been removed in
favor of declaring the individual elements as parameters
to the debug functions.  This reduces the cumulative stack
use during nested execution of ACPI function calls at the
cost of a small increase in the code size of the debug
version of the subsystem.  With assistance from Alexey
Starikovskiy and Len Brown.

Added the ACPI_GET_FUNCTION_NAME macro to enable the
compiler-dependent headers to define a macro that will
return the current function name at runtime (such as
__FUNCTION__ or _func_, etc.) The function name is used
by the debug trace output.  If ACPI_GET_FUNCTION_NAME
is not defined in the compiler-dependent header, the
function name is saved on the CPU stack (one pointer per
function.) This mechanism is used because apparently there
exists no standard ANSI-C defined macro that that returns
the function name.

Alexey Starikovskiy redesigned and reimplemented the
"Owner ID" mechanism used to track namespace objects
created/deleted by ACPI tables and control method
execution.  A bitmap is now used to allocate and free the
IDs, thus solving the wraparound problem present in the
previous implementation.  The size of the namespace node
descriptor was reduced by 2 bytes as a result.

Removed the UINT32_BIT and UINT16_BIT types that were used
for the bitfield flag definitions within the headers for
the predefined ACPI tables.  These have been replaced by
UINT8_BIT in order to increase the code portability of
the subsystem.  If the use of UINT8 remains a problem,
we may be forced to eliminate bitfields entirely because
of a lack of portability.

Alexey Starikovksiy enhanced the performance of
acpi_ut_update_object_reference.  This is a frequently used
function and this improvement increases the performance
of the entire subsystem.

Alexey Starikovskiy fixed several possible memory leaks
and the inverse - premature object deletion.

Signed-off-by: Len Brown <len.brown@intel.com>
2005-07-14 00:42:23 -04:00

329 lines
8.4 KiB
C

/******************************************************************************
*
* Module Name: utcache - local cache allocation routines
*
*****************************************************************************/
/*
* 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 ("utcache")
#ifdef ACPI_USE_LOCAL_CACHE
/*******************************************************************************
*
* FUNCTION: acpi_os_create_cache
*
* PARAMETERS: cache_name - Ascii name for the cache
* object_size - Size of each cached object
* max_depth - Maximum depth of the cache (in objects)
* return_cache - Where the new cache object is returned
*
* RETURN: Status
*
* DESCRIPTION: Create a cache object
*
******************************************************************************/
acpi_status
acpi_os_create_cache (
char *cache_name,
u16 object_size,
u16 max_depth,
struct acpi_memory_list **return_cache)
{
struct acpi_memory_list *cache;
ACPI_FUNCTION_ENTRY ();
if (!cache_name || !return_cache || (object_size < 16)) {
return (AE_BAD_PARAMETER);
}
/* Create the cache object */
cache = acpi_os_allocate (sizeof (struct acpi_memory_list));
if (!cache) {
return (AE_NO_MEMORY);
}
/* Populate the cache object and return it */
ACPI_MEMSET (cache, 0, sizeof (struct acpi_memory_list));
cache->link_offset = 8;
cache->list_name = cache_name;
cache->object_size = object_size;
cache->max_depth = max_depth;
*return_cache = cache;
return (AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_os_purge_cache
*
* PARAMETERS: Cache - Handle to cache object
*
* RETURN: Status
*
* DESCRIPTION: Free all objects within the requested cache.
*
******************************************************************************/
acpi_status
acpi_os_purge_cache (
struct acpi_memory_list *cache)
{
char *next;
ACPI_FUNCTION_ENTRY ();
if (!cache) {
return (AE_BAD_PARAMETER);
}
/* Walk the list of objects in this cache */
while (cache->list_head) {
/* Delete and unlink one cached state object */
next = *(ACPI_CAST_INDIRECT_PTR (char,
&(((char *) cache->list_head)[cache->link_offset])));
ACPI_MEM_FREE (cache->list_head);
cache->list_head = next;
cache->current_depth--;
}
return (AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_os_delete_cache
*
* PARAMETERS: Cache - Handle to cache object
*
* RETURN: Status
*
* DESCRIPTION: Free all objects within the requested cache and delete the
* cache object.
*
******************************************************************************/
acpi_status
acpi_os_delete_cache (
struct acpi_memory_list *cache)
{
acpi_status status;
ACPI_FUNCTION_ENTRY ();
/* Purge all objects in the cache */
status = acpi_os_purge_cache (cache);
if (ACPI_FAILURE (status)) {
return (status);
}
/* Now we can delete the cache object */
acpi_os_free (cache);
return (AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_os_release_object
*
* PARAMETERS: Cache - Handle to cache object
* Object - The object to be released
*
* RETURN: None
*
* DESCRIPTION: Release an object to the specified cache. If cache is full,
* the object is deleted.
*
******************************************************************************/
acpi_status
acpi_os_release_object (
struct acpi_memory_list *cache,
void *object)
{
acpi_status status;
ACPI_FUNCTION_ENTRY ();
if (!cache || !object) {
return (AE_BAD_PARAMETER);
}
/* If cache is full, just free this object */
if (cache->current_depth >= cache->max_depth) {
ACPI_MEM_FREE (object);
ACPI_MEM_TRACKING (cache->total_freed++);
}
/* Otherwise put this object back into the cache */
else {
status = acpi_ut_acquire_mutex (ACPI_MTX_CACHES);
if (ACPI_FAILURE (status)) {
return (status);
}
/* Mark the object as cached */
ACPI_MEMSET (object, 0xCA, cache->object_size);
ACPI_SET_DESCRIPTOR_TYPE (object, ACPI_DESC_TYPE_CACHED);
/* Put the object at the head of the cache list */
* (ACPI_CAST_INDIRECT_PTR (char,
&(((char *) object)[cache->link_offset]))) = cache->list_head;
cache->list_head = object;
cache->current_depth++;
(void) acpi_ut_release_mutex (ACPI_MTX_CACHES);
}
return (AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_os_acquire_object
*
* PARAMETERS: Cache - Handle to cache object
*
* RETURN: the acquired object. NULL on error
*
* DESCRIPTION: Get an object from the specified cache. If cache is empty,
* the object is allocated.
*
******************************************************************************/
void *
acpi_os_acquire_object (
struct acpi_memory_list *cache)
{
acpi_status status;
void *object;
ACPI_FUNCTION_NAME ("os_acquire_object");
if (!cache) {
return (NULL);
}
status = acpi_ut_acquire_mutex (ACPI_MTX_CACHES);
if (ACPI_FAILURE (status)) {
return (NULL);
}
ACPI_MEM_TRACKING (cache->requests++);
/* Check the cache first */
if (cache->list_head) {
/* There is an object available, use it */
object = cache->list_head;
cache->list_head = *(ACPI_CAST_INDIRECT_PTR (char,
&(((char *) object)[cache->link_offset])));
cache->current_depth--;
ACPI_MEM_TRACKING (cache->hits++);
ACPI_MEM_TRACKING (ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
"Object %p from %s cache\n", object, cache->list_name)));
status = acpi_ut_release_mutex (ACPI_MTX_CACHES);
if (ACPI_FAILURE (status)) {
return (NULL);
}
/* Clear (zero) the previously used Object */
ACPI_MEMSET (object, 0, cache->object_size);
}
else {
/* The cache is empty, create a new object */
ACPI_MEM_TRACKING (cache->total_allocated++);
/* Avoid deadlock with ACPI_MEM_CALLOCATE */
status = acpi_ut_release_mutex (ACPI_MTX_CACHES);
if (ACPI_FAILURE (status)) {
return (NULL);
}
object = ACPI_MEM_CALLOCATE (cache->object_size);
if (!object) {
return (NULL);
}
}
return (object);
}
#endif /* ACPI_USE_LOCAL_CACHE */