sched/core: Separate out io_schedule_prepare() and io_schedule_finish()

[mirror_ubuntu-artful-kernel.git] / kernel / sched / core.c

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 9fd37169b302c1ae2e87e0754cec8685a4a939fe..49ce1cb3d32074591670616e030abb334aa80558 100644 (file)
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -5128,25 +5128,48 @@ out_irq:
 }
 EXPORT_SYMBOL_GPL(yield_to);
 
+int io_schedule_prepare(void)
+{
+       int old_iowait = current->in_iowait;
+
+       current->in_iowait = 1;
+       blk_schedule_flush_plug(current);
+
+       return old_iowait;
+}
+
+void io_schedule_finish(int token)
+{
+       current->in_iowait = token;
+}
+
 /*
  * This task is about to go to sleep on IO. Increment rq->nr_iowait so
  * that process accounting knows that this is a task in IO wait state.
  */
 long __sched io_schedule_timeout(long timeout)
 {
-       int old_iowait = current->in_iowait;
+       int token;
        long ret;
 
-       current->in_iowait = 1;
-       blk_schedule_flush_plug(current);
-
+       token = io_schedule_prepare();
        ret = schedule_timeout(timeout);
-       current->in_iowait = old_iowait;
+       io_schedule_finish(token);
 
        return ret;
 }
 EXPORT_SYMBOL(io_schedule_timeout);
 
+void io_schedule(void)
+{
+       int token;
+
+       token = io_schedule_prepare();
+       schedule();
+       io_schedule_finish(token);
+}
+EXPORT_SYMBOL(io_schedule);
+
 /**
  * sys_sched_get_priority_max - return maximum RT priority.
  * @policy: scheduling class.