On Tue, Mar 28, 2017 at 01:32:01PM +0800, Huang, Ying wrote: > @@ -499,6 +499,19 @@ config FRONTSWAP > > If unsure, say Y to enable frontswap. > > +config ARCH_USES_THP_SWAP_CLUSTER > + bool > + default n
This is fine. > +config THP_SWAP_CLUSTER > + bool > + depends on SWAP && TRANSPARENT_HUGEPAGE && ARCH_USES_THP_SWAP_CLUSTER > + default y > + help > + Use one swap cluster to hold the contents of the THP > + (Transparent Huge Page) swapped out. The size of the swap > + cluster will be same as that of THP. But this is a super weird thing to ask the user. How would they know what to say, if we don't know? I don't think this should be a config knob at all. Merge the two config items into a simple config THP_SWAP_CLUSTER bool default n and let the archs with reasonable THP sizes select it.