include/linux/pid.h: use for_each_thread() in do_each_pid_thread()

while_each_pid_thread() is using while_each_thread(), which is unsafe
under RCU lock according to commit 0c740d0afc3b ("introduce
for_each_thread() to replace the buggy while_each_thread()").  Use
for_each_thread() in do_each_pid_thread() which is safe under RCU lock.

Link: http://lkml.kernel.org/r/201702011947.DBD56740.OMVHOLOtSJFFFQ@I-love.SAKURA.ne.jp
Link: http://lkml.kernel.org/r/1486041779-4401-2-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/include/linux/pid.h b/include/linux/pid.h
index 23705a53abbaad29347a2724f24e80c7f44e9341..298ead5512e55d2dd47aed1a035560cbbae80ab7 100644 (file)
--- a/include/linux/pid.h
+++ b/include/linux/pid.h
@@ -191,10 +191,10 @@ pid_t pid_vnr(struct pid *pid);
 #define do_each_pid_thread(pid, type, task)                            \
        do_each_pid_task(pid, type, task) {                             \
                struct task_struct *tg___ = task;                       \
-               do {
+               for_each_thread(tg___, task) {
 
 #define while_each_pid_thread(pid, type, task)                         \
-               } while_each_thread(tg___, task);                       \
+               }                                                       \
                task = tg___;                                           \
        } while_each_pid_task(pid, type, task)
 #endif /* _LINUX_PID_H */