On 07/01/2016 03:46 PM, Rafael J. Wysocki wrote: > On Fri, Jul 1, 2016 at 11:41 PM, Al Stone <ahs3@xxxxxxxxxx> wrote: >> On 07/01/2016 03:32 PM, Rafael J. Wysocki wrote: >>> On Fri, Jul 1, 2016 at 11:21 PM, Al Stone <ahs3@xxxxxxxxxx> wrote: >>>> Without this patch, the acpi_parse_entries_array() function will return >>>> the very first time there is any error found in either the array of >>>> callback functions or if one of the callbacks returns an non-zero value. >>>> However, the array of callbacks could still have valid entries further >>>> on in the array, or the callbacks may be able to process subsequent >>>> subtables without error. The change here makes the function consistent >>>> with its description so that it will properly return the sum of all >>>> matching entries for all proc handlers, instead of stopping abruptly >>>> as it does today. >>> >>> I'm not sure I follow. >>> >>> You seem to be saying that the function should process all of the >>> subtables etc even though errors have been found for some of them, but >>> it still will return an error in the end if there are any errors. How >>> exactly does it help to continue processing in case of an error, then? >> >> The use case I have in mind is to simply count all of the subtables of >> a certain type. If for some reason, the callback -- or any other callback >> -- fails, the traversal of all the subtables stops immediately. So, I >> could have two callbacks, and if the first one fails on the first subtable >> of its type, traversal stops. The count for the second callback will be >> zero which may or may not be correct. > > It will be zero, because the callback has not been invoked at all. > Why is this incorrect? > Because there could be additional subtables after the one causing a failure that the second callback could have counted; e.g., if the failure is on the first subtable of 20 in the MADT, the following 19 would be ignored, even if they were all the right subtype for the second callback. -- ciao, al ----------------------------------- Al Stone Software Engineer Red Hat, Inc. ahs3@xxxxxxxxxx ----------------------------------- -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
