On 4/22/2020 4:22 AM, leonid.ravich@xxxxxxxx wrote:
From: Leonid Ravich <Leonid.Ravich@xxxxxxx>
completion timeout might trigger unnesesery DMA engine hw reboot
in case of missed issue_pending() .
Just curious, are you hitting a use case where this is happening? And
what's causing the completion timeout?
Signed-off-by: Leonid Ravich <Leonid.Ravich@xxxxxxx>
---
drivers/dma/ioat/dma.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/drivers/dma/ioat/dma.c b/drivers/dma/ioat/dma.c
index 55a8cf1..2ab07a3 100644
--- a/drivers/dma/ioat/dma.c
+++ b/drivers/dma/ioat/dma.c
@@ -955,6 +955,13 @@ void ioat_timer_event(struct timer_list *t)
goto unlock_out;
}
+ /* handle missed issue pending case */
+ if (ioat_ring_pending(ioat_chan)) {
+ 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:
