#define deactivate_mm(tsk,mm) do { } while (0)
+extern void force_flush_all(void);
+
static inline void activate_mm(struct mm_struct *old, struct mm_struct *new)
{
+ /*
+ * This is called by fs/exec.c and fs/aio.c. In the first case, for an
+ * exec, we don't need to do anything as we're called from userspace
+ * and thus going to use a new host PID. In the second, we're called
+ * from a kernel thread, and thus need to go doing the mmap's on the
+ * host. Since they're very expensive, we want to avoid that as far as
+ * possible.
+ */
+ if (old != new && (current->flags & PF_BORROWED_MM))
+ force_flush_all();
}
static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,