utalloc.c

内核linux2.4.20,可跟rtlinux3.2打补丁 组成实时linux系统,编译内核

/******************************************************************************
 *
 * Module Name: utalloc - local cache and memory allocation routines
 *              $Revision: 106 $
 *
 *****************************************************************************/

/*
 *  Copyright (C) 2000, 2001 R. Byron Moore
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */


#include "acpi.h"
#include "acparser.h"
#include "acinterp.h"
#include "acnamesp.h"
#include "acglobal.h"

#define _COMPONENT          ACPI_UTILITIES
	 MODULE_NAME         ("utalloc")


/******************************************************************************
 *
 * FUNCTION:    Acpi_ut_release_to_cache
 *
 * PARAMETERS:  List_id             - Memory list/cache ID
 *              Object              - The object to be released
 *
 * RETURN:      None
 *
 * DESCRIPTION: Release an object to the specified cache.  If cache is full,
 *              the object is deleted.
 *
 ******************************************************************************/

void
acpi_ut_release_to_cache (
	u32                     list_id,
	void                    *object)
{
	ACPI_MEMORY_LIST        *cache_info;


	FUNCTION_ENTRY ();


	/* If walk cache is full, just free this wallkstate object */

	cache_info = &acpi_gbl_memory_lists[list_id];
	if (cache_info->cache_depth >= cache_info->max_cache_depth) {
		ACPI_MEM_FREE (object);
		ACPI_MEM_TRACKING (cache_info->total_freed++);
	}

	/* Otherwise put this object back into the cache */

	else {
		acpi_ut_acquire_mutex (ACPI_MTX_CACHES);

		/* Mark the object as cached */

		MEMSET (object, 0xCA, cache_info->object_size);
		((acpi_operand_object *) object)->common.data_type = ACPI_CACHED_OBJECT;

		/* Put the object at the head of the cache list */

		* (char **) (((char *) object) + cache_info->link_offset) = cache_info->list_head;
		cache_info->list_head = object;
		cache_info->cache_depth++;

		acpi_ut_release_mutex (ACPI_MTX_CACHES);
	}
}


/******************************************************************************
 *
 * FUNCTION:    Acpi_ut_acquire_from_cache
 *
 * PARAMETERS:  List_id             - Memory list ID
 *
 * RETURN:      A requested object.  NULL if the object could not be
 *              allocated.
 *
 * DESCRIPTION: Get an object from the specified cache.  If cache is empty,
 *              the object is allocated.
 *
 ******************************************************************************/

void *
acpi_ut_acquire_from_cache (
	u32                     list_id)
{
	ACPI_MEMORY_LIST        *cache_info;
	void                    *object;


	PROC_NAME ("Ut_acquire_from_cache");


	cache_info = &acpi_gbl_memory_lists[list_id];
	acpi_ut_acquire_mutex (ACPI_MTX_CACHES);
	ACPI_MEM_TRACKING (cache_info->cache_requests++);

	/* Check the cache first */

	if (cache_info->list_head) {
		/* There is an object available, use it */

		object = cache_info->list_head;
		cache_info->list_head = * (char **) (((char *) object) + cache_info->link_offset);

		ACPI_MEM_TRACKING (cache_info->cache_hits++);
		cache_info->cache_depth--;

#ifdef ACPI_DBG_TRACK_ALLOCATIONS
		ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Object %p from %s\n",
			object, acpi_gbl_memory_lists[list_id].list_name));
#endif

		acpi_ut_release_mutex (ACPI_MTX_CACHES);

		/* Clear (zero) the previously used Object */

		MEMSET (object, 0, cache_info->object_size);
	}

	else {
		/* The cache is empty, create a new object */

		/* Avoid deadlock with ACPI_MEM_CALLOCATE */

		acpi_ut_release_mutex (ACPI_MTX_CACHES);

		object = ACPI_MEM_CALLOCATE (cache_info->object_size);
		ACPI_MEM_TRACKING (cache_info->total_allocated++);
	}

	return (object);
}


/******************************************************************************
 *
 * FUNCTION:    Acpi_ut_delete_generic_cache
 *
 * PARAMETERS:  List_id         - Memory list ID
 *
 * RETURN:      None
 *
 * DESCRIPTION: Free all objects within the requested cache.
 *
 ******************************************************************************/

void
acpi_ut_delete_generic_cache (
	u32                     list_id)
{
	ACPI_MEMORY_LIST        *cache_info;
	char                    *next;


	FUNCTION_ENTRY ();


	cache_info = &acpi_gbl_memory_lists[list_id];
	while (cache_info->list_head) {
		/* Delete one cached state object */

		next = * (char **) (((char *) cache_info->list_head) + cache_info->link_offset);
		ACPI_MEM_FREE (cache_info->list_head);

		cache_info->list_head = next;
		cache_info->cache_depth--;
	}
}


#ifdef ACPI_DBG_TRACK_ALLOCATIONS


/*
 * These procedures are used for tracking memory leaks in the subsystem, and
 * they get compiled out when the ACPI_DBG_TRACK_ALLOCATIONS is not set.
 *
 * Each memory allocation is tracked via a doubly linked list.  Each
 * element contains the caller's component, module name, function name, and
 * line number.  Acpi_ut_allocate and Acpi_ut_callocate call
 * Acpi_ut_track_allocation to add an element to the list; deletion
 * occurs in the body of Acpi_ut_free.
 */


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ut_find_allocation
 *
 * PARAMETERS:  Address             - Address of allocated memory
 *
 * RETURN:      A list element if found; NULL otherwise.
 *
 * DESCRIPTION: Searches for an element in the global allocation tracking list.
 *
 ******************************************************************************/

acpi_debug_mem_block *
acpi_ut_find_allocation (
	u32                     list_id,
	void                    *address)
{
	acpi_debug_mem_block    *element;


	FUNCTION_ENTRY ();


	if (list_id > ACPI_MEM_LIST_MAX) {
		return (NULL);
	}

	element = acpi_gbl_memory_lists[list_id].list_head;

	/* Search for the address. */

	while (element) {
		if (element == address) {
			return (element);
		}

		element = element->next;
	}

	return (NULL);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ut_track_allocation
 *
 * PARAMETERS:  Address             - Address of allocated memory
 *              Size                - Size of the allocation
 *              Alloc_type          - MEM_MALLOC or MEM_CALLOC
 *              Component           - Component type of caller
 *              Module              - Source file name of caller
 *              Line                - Line number of caller
 *
 * RETURN:      None.
 *
 * DESCRIPTION: Inserts an element into the global allocation tracking list.
 *
 ******************************************************************************/

acpi_status
acpi_ut_track_allocation (
	u32                     list_id,
	acpi_debug_mem_block    *address,
	u32                     size,
	u8                      alloc_type,
	u32                     component,
	NATIVE_CHAR             *module,
	u32                     line)
{
	ACPI_MEMORY_LIST        *mem_list;
	acpi_debug_mem_block    *element;
	acpi_status             status = AE_OK;


	FUNCTION_TRACE_PTR ("Ut_track_allocation", address);


	if (list_id > ACPI_MEM_LIST_MAX) {
		return_ACPI_STATUS (AE_BAD_PARAMETER);
	}

	mem_list = &acpi_gbl_memory_lists[list_id];
	acpi_ut_acquire_mutex (ACPI_MTX_MEMORY);

	/*
	 * Search list for this address to make sure it is not already on the list.
	 * This will catch several kinds of problems.
	 */

	element = acpi_ut_find_allocation (list_id, address);
	if (element) {
		REPORT_ERROR (("Ut_track_allocation: Address already present in list! (%p)\n",
			address));

		ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Element %p Address %p\n", element, address));

		goto unlock_and_exit;
	}

	/* Fill in the instance data. */

	address->size      = size;
	address->alloc_type = alloc_type;
	address->component = component;
	address->line      = line;

	STRNCPY (address->module, module, MAX_MODULE_NAME);

	/* Insert at list head */

	if (mem_list->list_head) {
		((acpi_debug_mem_block *)(mem_list->list_head))->previous = address;
	}

	address->next = mem_list->list_head;
	address->previous = NULL;

	mem_list->list_head = address;


unlock_and_exit:
	acpi_ut_release_mutex (ACPI_MTX_MEMORY);
	return_ACPI_STATUS (status);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ut_remove_allocation
 *
 * PARAMETERS:  Address             - Address of allocated memory
 *              Component           - Component type of caller
 *              Module              - Source file name of caller
 *              Line                - Line number of caller
 *
 * RETURN:
 *
 * DESCRIPTION: Deletes an element from the global allocation tracking list.
 *
 ******************************************************************************/

acpi_status
acpi_ut_remove_allocation (
	u32                     list_id,
	acpi_debug_mem_block    *address,
	u32                     component,
	NATIVE_CHAR             *module,
	u32                     line)
{
	ACPI_MEMORY_LIST        *mem_list;


	FUNCTION_TRACE ("Ut_remove_allocation");


	if (list_id > ACPI_MEM_LIST_MAX) {
		return_ACPI_STATUS (AE_BAD_PARAMETER);
	}

	mem_list = &acpi_gbl_memory_lists[list_id];
	if (NULL == mem_list->list_head) {
		/* No allocations! */

		_REPORT_ERROR (module, line, component,
				("Ut_remove_allocation: Empty allocation list, nothing to free!\n"));

		return_ACPI_STATUS (AE_OK);
	}


	acpi_ut_acquire_mutex (ACPI_MTX_MEMORY);

	/* Unlink */

	if (address->previous) {
		(address->previous)->next = address->next;
	}
	else {
		mem_list->list_head = address->next;
	}

	if (address->next) {
		(address->next)->previous = address->previous;