diff options
| -rw-r--r-- | drivers/acpi/acpica/uttrack.c | 100 |
1 files changed, 71 insertions, 29 deletions
diff --git a/drivers/acpi/acpica/uttrack.c b/drivers/acpi/acpica/uttrack.c index 79f311c3d1c4..a424a9e3fea4 100644 --- a/drivers/acpi/acpica/uttrack.c +++ b/drivers/acpi/acpica/uttrack.c @@ -61,7 +61,9 @@ ACPI_MODULE_NAME("uttrack") /* Local prototypes */ -static struct acpi_debug_mem_block *acpi_ut_find_allocation(void *allocation); +static struct acpi_debug_mem_block *acpi_ut_find_allocation(struct + acpi_debug_mem_block + *allocation); static acpi_status acpi_ut_track_allocation(struct acpi_debug_mem_block *address, @@ -263,31 +265,61 @@ acpi_ut_free_and_track(void *allocation, * * PARAMETERS: allocation - Address of allocated memory * - * RETURN: A list element if found; NULL otherwise. + * RETURN: Three cases: + * 1) List is empty, NULL is returned. + * 2) Element was found. Returns Allocation parameter. + * 3) Element was not found. Returns position where it should be + * inserted into the list. * * DESCRIPTION: Searches for an element in the global allocation tracking list. + * If the element is not found, returns the location within the + * list where the element should be inserted. + * + * Note: The list is ordered by larger-to-smaller addresses. + * + * This global list is used to detect memory leaks in ACPICA as + * well as other issues such as an attempt to release the same + * internal object more than once. Although expensive as far + * as cpu time, this list is much more helpful for finding these + * types of issues than using memory leak detectors outside of + * the ACPICA code. * ******************************************************************************/ -static struct acpi_debug_mem_block *acpi_ut_find_allocation(void *allocation) +static struct acpi_debug_mem_block *acpi_ut_find_allocation(struct + acpi_debug_mem_block + *allocation) { struct acpi_debug_mem_block *element; - ACPI_FUNCTION_ENTRY(); - element = acpi_gbl_global_list->list_head; + if (!element) { + return (NULL); + } + + /* + * Search for the address. + * + * Note: List is ordered by larger-to-smaller addresses, on the + * assumption that a new allocation usually has a larger address + * than previous allocations. + */ + while (element > allocation) { - /* Search for the address. */ + /* Check for end-of-list */ - while (element) { - if (element == allocation) { + if (!element->next) { return (element); } element = element->next; } - return (NULL); + if (element == allocation) { + return (element); + } + + return (element->previous); } /******************************************************************************* @@ -301,7 +333,7 @@ static struct acpi_debug_mem_block *acpi_ut_find_allocation(void *allocation) * module - Source file name of caller * line - Line number of caller * - * RETURN: None. + * RETURN: Status * * DESCRIPTION: Inserts an element into the global allocation tracking list. * @@ -330,22 +362,18 @@ acpi_ut_track_allocation(struct acpi_debug_mem_block *allocation, } /* - * Search list for this address to make sure it is not already on the list. - * This will catch several kinds of problems. + * Search the global list for this address to make sure it is not + * already present. This will catch several kinds of problems. */ element = acpi_ut_find_allocation(allocation); - if (element) { + if (element == allocation) { ACPI_ERROR((AE_INFO, - "UtTrackAllocation: Allocation already present in list! (%p)", + "UtTrackAllocation: Allocation (%p) already present in global list!", allocation)); - - ACPI_ERROR((AE_INFO, "Element %p Address %p", - element, allocation)); - goto unlock_and_exit; } - /* Fill in the instance data. */ + /* Fill in the instance data */ allocation->size = (u32)size; allocation->alloc_type = alloc_type; @@ -355,17 +383,31 @@ acpi_ut_track_allocation(struct acpi_debug_mem_block *allocation, ACPI_STRNCPY(allocation->module, module, ACPI_MAX_MODULE_NAME); allocation->module[ACPI_MAX_MODULE_NAME - 1] = 0; - /* Insert at list head */ + if (!element) { - if (mem_list->list_head) { - ((struct acpi_debug_mem_block *)(mem_list->list_head))-> - previous = allocation; - } + /* Insert at list head */ + + if (mem_list->list_head) { + ((struct acpi_debug_mem_block *)(mem_list->list_head))-> + previous = allocation; + } + + allocation->next = mem_list->list_head; + allocation->previous = NULL; - allocation->next = mem_list->list_head; - allocation->previous = NULL; + mem_list->list_head = allocation; + } else { + /* Insert after element */ + + allocation->next = element->next; + allocation->previous = element; + + if (element->next) { + (element->next)->previous = allocation; + } - mem_list->list_head = allocation; + element->next = allocation; + } unlock_and_exit: status = acpi_ut_release_mutex(ACPI_MTX_MEMORY); @@ -381,7 +423,7 @@ acpi_ut_track_allocation(struct acpi_debug_mem_block *allocation, * module - Source file name of caller * line - Line number of caller * - * RETURN: + * RETURN: Status * * DESCRIPTION: Deletes an element from the global allocation tracking list. * @@ -443,7 +485,7 @@ acpi_ut_remove_allocation(struct acpi_debug_mem_block *allocation, * * FUNCTION: acpi_ut_dump_allocation_info * - * PARAMETERS: + * PARAMETERS: None * * RETURN: None * |