On Tue 12-03-19 19:04:43, Yafang Shao wrote: > On Mon, Mar 11, 2019 at 4:47 PM Michal Hocko <mhocko@xxxxxxxxxx> wrote: > > > > On Fri 01-03-19 15:38:54, Yafang Shao wrote: > > > If we want to know the zone type, we have to check whether > > > CONFIG_ZONE_DMA, CONFIG_ZONE_DMA32 and CONFIG_HIGHMEM are set or not, > > > that's not so convenient. > > > > > > We'd better show the zone type directly. > > > > I do agree that zone number is quite PITA to process in general but do > > we really need this information in the first place? Why do we even care? > > > > Sometimes we want to know this event occurs in which zone, then we can > get the information of this zone, > for example via /proc/zoneinfo. > It could give us more information for debugging. Could you be more specific please? > > Zones are an MM internal implementation details and the more we export > > to the userspace the more we are going to argue about breaking userspace > > when touching them. So I would rather not export that information unless > > it is terribly useful. > > > > I 'm not sure whether zone type is terribly useful or not, but the > 'zid' is useless at all. > > I don't agree that Zones are MM internal. > We can get the zone type in many ways, for example /proc/zoneinfo. > > If we show this event occurs in which zone, we'd better show the zone type, > or we should drop this 'zid'. Yes, I am suggesting the later. If somebody really needs it then I would like to see a _specific_ usecase. Then we can add the proper name. -- Michal Hocko SUSE Labs
