Preparation. Change the main loop in check_hung_uninterruptible_tasks() to use the nested for_each_process() + __for_each_thread() loops explicitly. Note that we use __for_each_thread(), not for_each_thread(). This way it is clear that the inner loop doesn't depend on 'g' after we read ->signal.
Signed-off-by: Oleg Nesterov <o...@redhat.com> --- kernel/hung_task.c | 23 ++++++++++++++--------- 1 files changed, 14 insertions(+), 9 deletions(-) diff --git a/kernel/hung_task.c b/kernel/hung_task.c index e0f90c2..4735b99 100644 --- a/kernel/hung_task.c +++ b/kernel/hung_task.c @@ -169,17 +169,22 @@ static void check_hung_uninterruptible_tasks(unsigned long timeout) return; rcu_read_lock(); - for_each_process_thread(g, t) { - if (!max_count--) - goto unlock; - if (!--batch_count) { - batch_count = HUNG_TASK_BATCHING; - if (!rcu_lock_break(g, t)) + for_each_process(g) { + struct signal_struct *sig = g->signal; + + __for_each_thread(sig, t) { + if (!max_count--) goto unlock; + + if (!--batch_count) { + batch_count = HUNG_TASK_BATCHING; + if (!rcu_lock_break(g, t)) + goto unlock; + } + /* use "==" to skip the TASK_KILLABLE tasks */ + if (t->state == TASK_UNINTERRUPTIBLE) + check_hung_task(t, timeout); } - /* use "==" to skip the TASK_KILLABLE tasks waiting on NFS */ - if (t->state == TASK_UNINTERRUPTIBLE) - check_hung_task(t, timeout); } unlock: rcu_read_unlock(); -- 1.5.5.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/