Re: [PATCH net 1/2] tg3: Fix for diasllow rx coalescing time to be 0
From: Rick Jones <hidden>
Date: 2016-08-03 16:06:08
On 08/02/2016 09:13 PM, skallam wrote:
quoted hunk ↗ jump to hunk
From: Satish Baddipadige <redacted> When the rx coalescing time is 0, interrupts are not generated from the controller and rx path hangs. To avoid this rx hang, updating the driver to not allow rx coalescing time to be 0. Signed-off-by: Satish Baddipadige <redacted> Signed-off-by: Siva Reddy Kallam <siva.kallam@broadcom.com> Signed-off-by: Michael Chan <michael.chan@broadcom.com> --- drivers/net/ethernet/broadcom/tg3.c | 1 + 1 files changed, 1 insertions(+), 0 deletions(-)diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c index ff300f7..f3c6c91 100644 --- a/drivers/net/ethernet/broadcom/tg3.c +++ b/drivers/net/ethernet/broadcom/tg3.c@@ -14014,6 +14014,7 @@ static int tg3_set_coalesce(struct net_device *dev, struct ethtool_coalesce *ec) } if ((ec->rx_coalesce_usecs > MAX_RXCOL_TICKS) || + (!ec->rx_coalesce_usecs) || (ec->tx_coalesce_usecs > MAX_TXCOL_TICKS) || (ec->rx_max_coalesced_frames > MAX_RXMAX_FRAMES) || (ec->tx_max_coalesced_frames > MAX_TXMAX_FRAMES) ||
Should anything then happen with:
/* No rx interrupts will be generated if both are zero */
if ((ec->rx_coalesce_usecs == 0) &&
(ec->rx_max_coalesced_frames == 0))
return -EINVAL;
which is the next block of code? The logic there seems to suggest that
it was intended to be able to have an rx_coalesce_usecs of 0 and rely on
packet arrival to trigger an interrupt. Presumably setting
rx_max_coalesced_frames to 1 to disable interrupt coalescing.
happy benchmarking,
rick jones