Benjamin Herrenschmidt wrote:

quoted

Which architecture are you interested in?  If it isn't x86, you can 
probably get anything past Linus ;)

I'll do some measurements to see what effect the batchable 
ptep_set_wrprotect() has on native.  If it's significant, I'll propose 
making it conditional on CONFIG_PARAVIRT.
    

Oh, I mostly think about powerpc, I just wondered if I could re-use
your new stuff in that context. Mostly idle thoughts at this stage, I
haven't looked seriously.
  

There are general-purpose hooks in the common code which architectures 
can implement however they like.  In x86-land we hook them up to pvops, 
but you can handle them however you want.

I have an old patch set to batch forks (and mprotect etc...) TLB
invalidations (which is what I really want to batch on powerpc, more
than the actual PTE changes) that involves subtle changes to the
batching mechanisms etc...
  

Do you mean setting up batches of per-page tlb shootdowns rather than 
going a global tlb flush at the end?

    J