block: cleanup the block plug helper functions

It's a bit of a mess currently. task->plug is being cleared
and reset in __blk_finish_plug(), and blk_finish_plug() is
testing for a NULL plug which cannot happen even from schedule()
anymore since it uses blk_needs_flush_plug() to determine
whether to call into this function at all.

So get rid of some of the cruft.

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

1 files changed, 6 insertions, 18 deletions

diff --git a/block/blk-core.c b/block/blk-core.c
index 36b1a7559f94..b598fa7720d4 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -2671,7 +2671,7 @@ static void queue_unplugged(struct request_queue *q, unsigned int depth)
                 q->unplugged_fn(q);
 }
 
-static void flush_plug_list(struct blk_plug *plug)
+void blk_flush_plug_list(struct blk_plug *plug)
 {
         struct request_queue *q;
         unsigned long flags;
@@ -2733,28 +2733,16 @@ static void flush_plug_list(struct blk_plug *plug)
 
         local_irq_restore(flags);
 }
-
-static void __blk_finish_plug(struct task_struct *tsk, struct blk_plug *plug)
-{
-        flush_plug_list(plug);
-
-        if (plug == tsk->plug)
-                tsk->plug = NULL;
-}
+EXPORT_SYMBOL(blk_flush_plug_list);
 
 void blk_finish_plug(struct blk_plug *plug)
 {
-        if (plug)
-                __blk_finish_plug(current, plug);
-}
-EXPORT_SYMBOL(blk_finish_plug);
+        blk_flush_plug_list(plug);
 
-void __blk_flush_plug(struct task_struct *tsk, struct blk_plug *plug)
-{
-        __blk_finish_plug(tsk, plug);
-        tsk->plug = plug;
+        if (plug == current->plug)
+                current->plug = NULL;
 }
-EXPORT_SYMBOL(__blk_flush_plug);
+EXPORT_SYMBOL(blk_finish_plug);
 
 int __init blk_dev_init(void)
 {