Re: [PATCH v2] dmaengine: ioat setting ioat timeout as module parameter

[Dave Jiang]

On 7/1/2020 11:48 AM, leonid.rav...@dell.com wrote:

From: Leonid Ravich <leonid.rav...@emc.com>

DMA transaction time to completion  is a function of
PCI bandwidth,transaction size and a queue depth.
So hard coded value for timeouts might be wrong
for some scenarios.

Signed-off-by: Leonid Ravich <leonid.rav...@emc.com>

Reviewed-by: Dave Jiang <dave.ji...@intel.com>

---
Changing in v2
   - misspelling of completion
  drivers/dma/ioat/dma.c | 12 ++++++++++++
  drivers/dma/ioat/dma.h |  2 --
  2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/ioat/dma.c b/drivers/dma/ioat/dma.c
index 8ad0ad861c86..fd782aee02d9 100644
--- a/drivers/dma/ioat/dma.c
+++ b/drivers/dma/ioat/dma.c
@@ -26,6 +26,18 @@

#include "../dmaengine.h" +int completion_timeout = 200;

+module_param(completion_timeout, int, 0644);
+MODULE_PARM_DESC(completion_timeout,
+               "set ioat completion timeout [msec] (default 200 [msec])");
+int idle_timeout = 2000;
+module_param(idle_timeout, int, 0644);
+MODULE_PARM_DESC(idle_timeout,
+               "set ioat idel timeout [msec] (default 2000 [msec])");
+
+#define IDLE_TIMEOUT msecs_to_jiffies(idle_timeout)
+#define COMPLETION_TIMEOUT msecs_to_jiffies(completion_timeout)
+
  static char *chanerr_str[] = {
        "DMA Transfer Source Address Error",
        "DMA Transfer Destination Address Error",
diff --git a/drivers/dma/ioat/dma.h b/drivers/dma/ioat/dma.h
index e6b622e1ba92..f7f31fdf14cf 100644
--- a/drivers/dma/ioat/dma.h
+++ b/drivers/dma/ioat/dma.h
@@ -104,8 +104,6 @@ struct ioatdma_chan {
        #define IOAT_RUN 5
        #define IOAT_CHAN_ACTIVE 6
        struct timer_list timer;
-       #define COMPLETION_TIMEOUT msecs_to_jiffies(100)
-       #define IDLE_TIMEOUT msecs_to_jiffies(2000)
        #define RESET_DELAY msecs_to_jiffies(100)
        struct ioatdma_device *ioat_dma;
        dma_addr_t completion_dma;