coredump: change zap_threads() and zap_process() to use for_each_thread()

Change zap_threads() paths to use for_each_thread() rather than
while_each_thread().

While at it, change zap_threads() to avoid the nested if's to make the
code more readable and lessen the indentation.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Kyle Walker <kwalker@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Stanislav Kozina <skozina@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 13 insertions, 14 deletions

diff --git a/fs/coredump.c b/fs/coredump.c
index c66bb0572265..1777331eee76 100644
--- a/fs/coredump.c
+++ b/fs/coredump.c
@@ -290,15 +290,14 @@ static int zap_process(struct task_struct *start, int exit_code, int flags)
         start->signal->group_exit_code = exit_code;
         start->signal->group_stop_count = 0;
 
-        t = start;
-        do {
+        for_each_thread(start, t) {
                 task_clear_jobctl_pending(t, JOBCTL_PENDING_MASK);
                 if (t != current && t->mm) {
                         sigaddset(&t->pending.signal, SIGKILL);
                         signal_wake_up(t, 1);
                         nr++;
                 }
-        } while_each_thread(start, t);
+        }
 
         return nr;
 }
@@ -360,18 +359,18 @@ static int zap_threads(struct task_struct *tsk, struct mm_struct *mm,
                         continue;
                 if (g->flags & PF_KTHREAD)
                         continue;
-                p = g;
-                do {
-                        if (p->mm) {
-                                if (unlikely(p->mm == mm)) {
-                                        lock_task_sighand(p, &flags);
-                                        nr += zap_process(p, exit_code,
-                                                          SIGNAL_GROUP_EXIT);
-                                        unlock_task_sighand(p, &flags);
-                                }
-                                break;
+
+                for_each_thread(g, p) {
+                        if (unlikely(!p->mm))
+                                continue;
+                        if (unlikely(p->mm == mm)) {
+                                lock_task_sighand(p, &flags);
+                                nr += zap_process(p, exit_code,
+                                                        SIGNAL_GROUP_EXIT);
+                                unlock_task_sighand(p, &flags);
                         }
-                } while_each_thread(g, p);
+                        break;
+                }
         }
         rcu_read_unlock();
 done: