oom: kill the insufficient and no longer needed PT_TRACE_EXIT check

After the previous patch we can remove the PT_TRACE_EXIT check in
oom_scan_process_thread(), it was added to handle the case when the
coredumping was "frozen" by ptrace, but it doesn't really work.  If
nothing else, we would need to check all threads which could share the
same ->mm to make it more or less correct.

Signed-off-by: Oleg Nesterov <[email protected]>
Cc: Cong Wang <[email protected]>
Cc: David Rientjes <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Cc: "Rafael J. Wysocki" <[email protected]>
Cc: Tejun Heo <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

1 files changed, 3 insertions, 8 deletions

diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index f694ef0d9f9a..d503e9ce1c7b 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -281,14 +281,9 @@ enum oom_scan_t oom_scan_process_thread(struct task_struct *task,
 	if (oom_task_origin(task))
 		return OOM_SCAN_SELECT;
 
-	if (task_will_free_mem(task) && !force_kill) {
-		/*
-		 * If this task is not being ptraced on exit, then wait for it
-		 * to finish before killing some other task unnecessarily.
-		 */
-		if (!(task->group_leader->ptrace & PT_TRACE_EXIT))
-			return OOM_SCAN_ABORT;
-	}
+	if (task_will_free_mem(task) && !force_kill)
+		return OOM_SCAN_ABORT;
+
 	return OOM_SCAN_OK;
 }