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According to the docs the >>> counters >>> will return "Unavailable" right after reconfigure so it seems that there >>> are scenarios where an "assigned" counter returns "Unavailable". It >>> seems >>> more >>> useful to return "Unassigned" that will have a new specific meaning that >>> overloading existing "Unavailable" that has original meaning of "try >>> again" .... >>> but in this case trying again will be futile. >> >> Hardware returns "Unavailable" in both the cases. So, thought of >> reporting the same without any interpretation. >> > > I do not see these as the same. When a counter is assigned and its > read returns "Unavailable" then the user reasonably expects that > retry will work. > When a counter is not assigned then no amount of retries will result > in data. How is user space expected to distinguish between the two > scenarios that return the same error with such significantly different > meaning? rdtgroup_mondata_shows() can just peek into the monitor > group state and see if a counter is assigned and immediately > return "Unassigned" if no counter is assigned, no? I see no need > for it to IPI another CPU and try to read a counter that it already knows > will be futile. This seems unnecessary and the generic "Unavailable" is > not helpful to user space. > Sure. Will change it to report "Unassigned" in these cases. Thanks -- - Babu Moger