I wonder whether it makes sense to expose to userspace somehow whether mremap is "fast" for a particular architecture. If a feature relies on fast mremap, it might be better for some userland component to disable that feature entirely rather than blindly use mremap and end up performing very poorly. If we're disabling fast mremap when THP is enabled, the userland component can't just rely on an architecture switch and some kind of runtime feature detection becomes even more important. On Fri, Oct 12, 2018 at 6:44 PM, Joel Fernandes <joel@xxxxxxxxxxxxxxxxx> wrote: > On Fri, Oct 12, 2018 at 06:39:45PM -0700, Daniel Colascione wrote: >> Not 32-bit ARM? > > Well, I didn't want to enable every possible architecture we could in a > single go. Certainly arm32 can be a follow on enablement as can be other > architectures. The point of this series is to upstream this feature and > enable a hand-picked few architectures as a first step. > > thanks, > > - Joel >
