// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
*
* Module Name: utcache - local cache allocation routines
*
* Copyright (C) 2000 - 2023, Intel Corp.
*
*****************************************************************************/
#include <acpi/acpi.h>
#include "accommon.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) {
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 */
memset(cache, 0, sizeof(struct acpi_memory_list));
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)
{
void *next;
acpi_status status;
ACPI_FUNCTION_ENTRY();
if (!cache) {
return (AE_BAD_PARAMETER);
}
status = acpi_ut_acquire_mutex(ACPI_MTX_CACHES);
if (ACPI_FAILURE(status)) {
return (status);
}
/* Walk the list of objects in this cache */
while (cache->list_head) {
/* Delete and unlink one cached state object */
next = ACPI_GET_DESCRIPTOR_PTR(cache->list_head);
ACPI_FREE(cache->list_head);
cache->list_head = next;
cache->current_depth--;
}
(void)acpi_ut_release_mutex(ACPI_MTX_CACHES);
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_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 */
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_SET_DESCRIPTOR_PTR(object, 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_TRACE(os_acquire_object);
if (!cache) {
return_PTR(NULL);
}
status = acpi_ut_acquire_mutex(ACPI_MTX_CACHES);
if (ACPI_FAILURE(status)) {
return_PTR(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_GET_DESCRIPTOR_PTR(object);
cache->current_depth--;
ACPI_MEM_TRACKING(cache->hits++);
ACPI_DEBUG_PRINT_RAW((ACPI_DB_EXEC,
"%s: Object %p from %s cache\n",
ACPI_GET_FUNCTION_NAME, object,
cache->list_name));
status = acpi_ut_release_mutex(ACPI_MTX_CACHES);
if (ACPI_FAILURE(status)) {
return_PTR(NULL);
}
/* Clear (zero) the previously used Object */
memset(object, 0, cache->object_size);
} else {
/* The cache is empty, create a new object */
ACPI_MEM_TRACKING(cache->total_allocated++);
#ifdef ACPI_DBG_TRACK_ALLOCATIONS
if ((cache->total_allocated - cache->total_freed) >
cache->max_occupied) {
cache->max_occupied =
cache->total_allocated - cache->total_freed;
}
#endif
/* Avoid deadlock with ACPI_ALLOCATE_ZEROED */
status = acpi_ut_release_mutex(ACPI_MTX_CACHES);
if (ACPI_FAILURE(status)) {
return_PTR(NULL);
}
object = ACPI_ALLOCATE_ZEROED(cache->object_size);
if (!object) {
return_PTR(NULL);
}
}
return_PTR(object);
}
#endif /* ACPI_USE_LOCAL_CACHE */
Codebase Browser
linux