[PATCH 1/4] mm/mempolicy: kernel_migrate_pages: simplify the usage of put_task_struct()

[Oleg Nesterov <oleg@redhat.com>]

kernel_migrate_pages() calls put_task_struct() twice; this complicates the
code. Move put_task_struct() to the unified exit path. This also allows us
to move the "out_put" label up and avoid another goto.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
---
 mm/mempolicy.c | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 4e4421b22b59..4326dff16aa6 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1922,25 +1922,20 @@ static int kernel_migrate_pages(pid_t pid, unsigned long maxnode,
 		goto out_put;
 
 	mm = get_task_mm(task);
-	put_task_struct(task);
-
 	if (!mm) {
 		err = -EINVAL;
-		goto out;
+		goto out_put;
 	}
 
 	err = do_migrate_pages(mm, old, new,
 		capable(CAP_SYS_NICE) ? MPOL_MF_MOVE_ALL : MPOL_MF_MOVE);
 
 	mmput(mm);
+out_put:
+	put_task_struct(task);
 out:
 	NODEMASK_SCRATCH_FREE(scratch);
-
 	return err;
-
-out_put:
-	put_task_struct(task);
-	goto out;
 }
 
 SYSCALL_DEFINE4(migrate_pages, pid_t, pid, unsigned long, maxnode,
-- 
2.52.0