ioat: wait for self-test completion

As part of the ioat_dma self-test it performs a printk from a completion
callback.  Depending on the system console configuration this output can
take longer than a millisecond causing the self-test to fail.  Introduce a
completion with a generous timeout to mitigate this failure.

Cc: <stable@kernel.org>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/drivers/dma/ioat_dma.c b/drivers/dma/ioat_dma.c
index ecd743f..6607fdd 100644 (file)
--- a/drivers/dma/ioat_dma.c
+++ b/drivers/dma/ioat_dma.c
@@ -1341,10 +1341,12 @@ static void ioat_dma_start_null_desc(struct ioat_dma_chan *ioat_chan)
  */
 #define IOAT_TEST_SIZE 2000
 
+DECLARE_COMPLETION(test_completion);
 static void ioat_dma_test_callback(void *dma_async_param)
 {
        printk(KERN_ERR "ioatdma: ioat_dma_test_callback(%p)\n",
                dma_async_param);
+       complete(&test_completion);
 }
 
 /**
@@ -1410,7 +1412,8 @@ static int ioat_dma_self_test(struct ioatdma_device *device)
                goto free_resources;
        }
        device->common.device_issue_pending(dma_chan);
-       msleep(1);
+
+       wait_for_completion_timeout(&test_completion, msecs_to_jiffies(3000));
 
        if (device->common.device_is_tx_complete(dma_chan, cookie, NULL, NULL)
                                        != DMA_SUCCESS) {