Martin Schwidefsky wrote: > On Fri, 2006-09-01 at 07:57 -0700, Dave Hansen wrote: >>> +#define PG_state_change 21 /* HV page state is changing. */ >>> +#define PG_discarded 22 /* HV page has been discarded. */ >> We're already desperately short on page flags on 32-bit architectures. >> It seems a wee bit silly to add two arch-generic flags for what is a >> very specialized arch-specific feature at this point. > > There are even three additional page flags if you apply the full set of > patches. > >> I know that there are 32-bit s390 kernels, but would this be a >> reasonable feature to restrict to only 64-bit kernels? That might be a >> decent compromise. > > Yes, it is definitly an option to make this a 64-bit only features. In > particular because the ESSA instruction that is used on s390 is only > available in zarch mode (=64 bit). Wow. Well there are only 7 extra bits available in 64 bit mode (the FIELDS area is larger on 64bit machines). Do we really, really need three new bits. What are they being used for here. -apw
