[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 <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: linux-arch@vger.kernel.org
Cc: James Bottomley <James.Bottomley@SteelEye.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/fork.c b/kernel/fork.c
index 6af959c..ffccefb 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -286,6 +286,8 @@
if (retval)
goto out;
}
+ /* a new mm has just been created */
+ arch_dup_mmap(oldmm, mm);
retval = 0;
out:
up_write(&mm->mmap_sem);