move exit_task_work() past exit_files() et.al.

... and get rid of PF_EXITING check in task_work_add().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 11 insertions, 19 deletions

diff --git a/kernel/task_work.c b/kernel/task_work.c
index 76266fb665d..fb396089f66 100644
--- a/kernel/task_work.c
+++ b/kernel/task_work.c
@@ -5,34 +5,26 @@
 int
 task_work_add(struct task_struct *task, struct callback_head *twork, bool notify)
 {
+        struct callback_head *last, *first;
         unsigned long flags;
-        int err = -ESRCH;
 
-#ifndef TIF_NOTIFY_RESUME
-        if (notify)
-                return -ENOTSUPP;
-#endif
         /*
-         * We must not insert the new work if the task has already passed
-         * exit_task_work(). We rely on do_exit()->raw_spin_unlock_wait()
-         * and check PF_EXITING under pi_lock.
+         * Not inserting the new work if the task has already passed
+         * exit_task_work() is the responisbility of callers.
          */
         raw_spin_lock_irqsave(&task->pi_lock, flags);
-        if (likely(!(task->flags & PF_EXITING))) {
-                struct callback_head *last = task->task_works;
-                struct callback_head *first = last ? last->next : twork;
-                twork->next = first;
-                if (last)
-                        last->next = twork;
-                task->task_works = twork;
-                err = 0;
-        }
+        last = task->task_works;
+        first = last ? last->next : twork;
+        twork->next = first;
+        if (last)
+                last->next = twork;
+        task->task_works = twork;
         raw_spin_unlock_irqrestore(&task->pi_lock, flags);
 
         /* test_and_set_bit() implies mb(), see tracehook_notify_resume(). */
-        if (likely(!err) && notify)
+        if (notify)
                 set_notify_resume(task);
-        return err;
+        return 0;
 }
 
 struct callback_head *