Re: [PATCH V2 net 13/20] net/ena: change driver's default timeouts

[Netanel Belgazal]

On 12/05/2016 06:35 AM, Matt Wilson wrote:
> On Sun, Dec 04, 2016 at 03:19:31PM +0200, Netanel Belgazal wrote:
>
> ... because? (they turned out to be too aggressive, I believe.)

Yes, The timeout were too aggressive on some specific machines.

> > Signed-off-by: Netanel Belgazal <netanel@xxxxxxxxxxxxxxxxx>
> > ---
> >   drivers/net/ethernet/amazon/ena/ena_com.c    | 4 ++--
> >   drivers/net/ethernet/amazon/ena/ena_netdev.h | 7 ++++---
> >   2 files changed, 6 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/net/ethernet/amazon/ena/ena_com.c b/drivers/net/ethernet/amazon/ena/ena_com.c
> > index 4147d6e..a550c8a 100644
> > --- a/drivers/net/ethernet/amazon/ena/ena_com.c
> > +++ b/drivers/net/ethernet/amazon/ena/ena_com.c
> > @@ -36,9 +36,9 @@
> >   /*****************************************************************************/
> >   
> >   /* Timeout in micro-sec */
> > -#define ADMIN_CMD_TIMEOUT_US (1000000)
> > +#define ADMIN_CMD_TIMEOUT_US (3000000)
> >   
> > -#define ENA_ASYNC_QUEUE_DEPTH 4
> > +#define ENA_ASYNC_QUEUE_DEPTH 16
> Why is this changed at the same time?

It related to the too aggressive thresholds.
On some heavy loaded system we reached to a state where the AENQ
was full so the driver missed some events.


> >   #define ENA_ADMIN_QUEUE_DEPTH 32
> >   
> >   #define MIN_ENA_VER (((ENA_COMMON_SPEC_VERSION_MAJOR) << \
> > diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.h b/drivers/net/ethernet/amazon/ena/ena_netdev.h
> > index c081fd3..ed42e07 100644
> > --- a/drivers/net/ethernet/amazon/ena/ena_netdev.h
> > +++ b/drivers/net/ethernet/amazon/ena/ena_netdev.h
> > @@ -39,6 +39,7 @@
> >   #include <linux/interrupt.h>
> >   #include <linux/netdevice.h>
> >   #include <linux/skbuff.h>
> > +#include <linux/u64_stats_sync.h>
> This change seems unrelated.

Removed to a different patch (will be submitted in a new patchset)
> >   #include "ena_com.h"
> >   #include "ena_eth_com.h"
> > @@ -100,7 +101,7 @@
> >   /* Number of queues to check for missing queues per timer service */
> >   #define ENA_MONITORED_TX_QUEUES	4
> >   /* Max timeout packets before device reset */
> > -#define MAX_NUM_OF_TIMEOUTED_PACKETS 32
> > +#define MAX_NUM_OF_TIMEOUTED_PACKETS 128
> >   
> >   #define ENA_TX_RING_IDX_NEXT(idx, ring_size) (((idx) + 1) & ((ring_size) - 1))
> >   
> > @@ -116,9 +117,9 @@
> >   #define ENA_IO_IRQ_IDX(q)		(ENA_IO_IRQ_FIRST_IDX + (q))
> >   
> >   /* ENA device should send keep alive msg every 1 sec.
> > - * We wait for 3 sec just to be on the safe side.
> > + * We wait for 6 sec just to be on the safe side.
> >    */
> > -#define ENA_DEVICE_KALIVE_TIMEOUT	(3 * HZ)
> > +#define ENA_DEVICE_KALIVE_TIMEOUT	(6 * HZ)
> >   
> >   #define ENA_MMIO_DISABLE_REG_READ	BIT(0)
> >