Minor cleanup. de_thread()->setmax_mm_hiwater_rss() looks a bit
strange, move it into exec_mmap() which plays with old_mm.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
---
 fs/exec.c |    4 +---
 1 files changed, 1 insertions(+), 3 deletions(-)

diff --git a/fs/exec.c b/fs/exec.c
index 218d074..7f84e86 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -848,6 +848,7 @@ static int exec_mmap(struct mm_struct *mm)
 	if (old_mm) {
 		up_read(&old_mm->mmap_sem);
 		BUG_ON(active_mm != old_mm);
+		setmax_mm_hiwater_rss(&tsk->signal->maxrss, old_mm);
 		mm_update_next_owner(old_mm);
 		mmput(old_mm);
 		return 0;
@@ -978,9 +979,6 @@ no_thread_group:
 	/* we have changed execution domain */
 	tsk->exit_signal = SIGCHLD;
 
-	if (current->mm)
-		setmax_mm_hiwater_rss(&sig->maxrss, current->mm);
-
 	exit_itimers(sig);
 	flush_itimer_signals();
 
-- 
1.5.5.1