[PATCH] x86: PARAVIRT: add hooks to intercept mm creation and destruction

Add hooks to allow a paravirt implementation to track the lifetime of
an mm.  Paravirtualization requires three hooks, but only two are
needed in common code.  They are:

arch_dup_mmap, which is called when a new mmap is created at fork

arch_exit_mmap, which is called when the last process reference to an
  mm is dropped, which typically happens on exit and exec.

The third hook is activate_mm, which is called from the arch-specific
activate_mm() macro/function, and so doesn't need stub versions for
other architectures.  It's called when an mm is first used.

Signed-off-by: Jeremy Fitzhardinge <[email protected]>
Signed-off-by: Andi Kleen <[email protected]>
Cc: [email protected]
Cc: James Bottomley <[email protected]>
Acked-by: Ingo Molnar <[email protected]>

include/asm-parisc/mmu_context.h

@@ -5,6 +5,7 @@
 #include <asm/atomic.h>
 #include <asm/pgalloc.h>
 #include <asm/pgtable.h>
+#include <asm-generic/mm_hooks.h>
 
 static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
 {