[PATCH v2 3/3] dmaengine: ioat: adding missed issue_pending to timeout handler

[leonid . ravich]

From: Leonid Ravich <Leonid.Ravich@xxxxxxx>

completion timeout might trigger unnesesery DMA engine hw reboot
in case of missed issue_pending() .

Acked-by: Dave Jiang <dave.jiang@xxxxxxxxx>
Signed-off-by: Leonid Ravich <Leonid.Ravich@xxxxxxx>
---
Changing in v2
  - add log in case of such scenario 
 drivers/dma/ioat/dma.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/dma/ioat/dma.c b/drivers/dma/ioat/dma.c
index 55a8cf1..a958aaf 100644
--- a/drivers/dma/ioat/dma.c
+++ b/drivers/dma/ioat/dma.c
@@ -955,6 +955,14 @@ void ioat_timer_event(struct timer_list *t)
 		goto unlock_out;
 	}
 
+	/* handle missed issue pending case */
+	if (ioat_ring_pending(ioat_chan)) {
+		dev_dbg(to_dev(ioat_chan), "Complition timeout while pending\n")
+		spin_lock_bh(&ioat_chan->prep_lock);
+		__ioat_issue_pending(ioat_chan);
+		spin_unlock_bh(&ioat_chan->prep_lock);
+	}
+
 	set_bit(IOAT_COMPLETION_ACK, &ioat_chan->state);
 	mod_timer(&ioat_chan->timer, jiffies + COMPLETION_TIMEOUT);
 unlock_out:
-- 
1.9.3