[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/mm/mmap.c b/mm/mmap.c
index 84f997d..88da687 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -29,6 +29,7 @@
#include <asm/uaccess.h>
#include <asm/cacheflush.h>
#include <asm/tlb.h>
+#include <asm/mmu_context.h>
#ifndef arch_mmap_check
#define arch_mmap_check(addr, len, flags) (0)
@@ -1979,6 +1980,9 @@
unsigned long nr_accounted = 0;
unsigned long end;
+ /* mm's last user has gone, and its about to be pulled down */
+ arch_exit_mmap(mm);
+
lru_add_drain();
flush_cache_mm(mm);
tlb = tlb_gather_mmu(mm, 1);