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 <oleg@redhat.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index f694ef0d9f9aca458d2c07a6e2cd638c7a2289aa..d503e9ce1c7b7f82b1fa10918c34d933b23e3b01 100644 (file)
--- 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;
 }