On Tue, 2012-07-24 at 04:04 +0000, Tabi Timur-B04825 wrote: > Benjamin Herrenschmidt wrote: > > Sure but I don't want to create the zones in the first place (and thus > > introduce the added pressure on the memory management) on machines that > > don't need it. > > One thing that does confuse me -- by default, we don't create a > ZONE_NORMAL. We only create a ZONE_DMA. Why is that? Shouldn't it be > the other way around?
Because ZONE_NORMAL allocations can be serviced from the ZONE_DMA while the other way isn't possible. Especially in the old days, there were quite a few cases of drivers and/or subsystems who were a bit heavy handed at using ZONE_DMA, so not having one would essentially make them not work at all. Cheers, Ben. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
