From: Eric Dumazet <eduma...@google.com>
1) In the case where rate == priv->pkt_rate_low == priv->pkt_rate_high,
mlx4_en_auto_moderation() does a divide by zero.
2) We want to properly change the moderation parameters if rx_frames
was changed (like in ethtool -C eth0 rx-frames 16)
Signed-off-by: Eric Dumazet <eduma...@google.com>
---
drivers/net/ethernet/mellanox/mlx4/en_netdev.c | 24 ++++++++-------
1 file changed, 14 insertions(+), 10 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
index
3b4961a8e8e44d6987ebd23f9239e747c7fc6cd5..ab3801d724ede4ab19958b2a1a214cfbe901c370
100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
@@ -1384,6 +1384,7 @@ static void mlx4_en_set_default_moderation(struct
mlx4_en_priv *priv)
static void mlx4_en_auto_moderation(struct mlx4_en_priv *priv)
{
unsigned long period = (unsigned long) (jiffies -
priv->last_moder_jiffies);
+ u32 pkt_rate_high, pkt_rate_low;
struct mlx4_en_cq *cq;
unsigned long packets;
unsigned long rate;
@@ -1397,37 +1398,40 @@ static void mlx4_en_auto_moderation(struct mlx4_en_priv
*priv)
if (!priv->adaptive_rx_coal || period < priv->sample_interval * HZ)
return;
+ pkt_rate_low = READ_ONCE(priv->pkt_rate_low);
+ pkt_rate_high = READ_ONCE(priv->pkt_rate_high);
+
for (ring = 0; ring < priv->rx_ring_num; ring++) {
rx_packets = READ_ONCE(priv->rx_ring[ring]->packets);
rx_bytes = READ_ONCE(priv->rx_ring[ring]->bytes);
- rx_pkt_diff = ((unsigned long) (rx_packets -
- priv->last_moder_packets[ring]));
+ rx_pkt_diff = rx_packets - priv->last_moder_packets[ring];
packets = rx_pkt_diff;
rate = packets * HZ / period;
- avg_pkt_size = packets ? ((unsigned long) (rx_bytes -
- priv->last_moder_bytes[ring])) / packets : 0;
+ avg_pkt_size = packets ? (rx_bytes -
+ priv->last_moder_bytes[ring]) / packets : 0;
/* Apply auto-moderation only when packet rate
* exceeds a rate that it matters */
if (rate > (MLX4_EN_RX_RATE_THRESH / priv->rx_ring_num) &&
avg_pkt_size > MLX4_EN_AVG_PKT_SMALL) {
- if (rate < priv->pkt_rate_low)
+ if (rate <= pkt_rate_low)
moder_time = priv->rx_usecs_low;
- else if (rate > priv->pkt_rate_high)
+ else if (rate >= pkt_rate_high)
moder_time = priv->rx_usecs_high;
else
- moder_time = (rate - priv->pkt_rate_low) *
+ moder_time = (rate - pkt_rate_low) *
(priv->rx_usecs_high -
priv->rx_usecs_low) /
- (priv->pkt_rate_high -
priv->pkt_rate_low) +
+ (pkt_rate_high - pkt_rate_low) +
priv->rx_usecs_low;
} else {
moder_time = priv->rx_usecs_low;
}
- if (moder_time != priv->last_moder_time[ring]) {
+ cq = priv->rx_cq[ring];
+ if (moder_time != priv->last_moder_time[ring] ||
+ cq->moder_cnt != priv->rx_frames) {
priv->last_moder_time[ring] = moder_time;
- cq = priv->rx_cq[ring];
cq->moder_time = moder_time;
cq->moder_cnt = priv->rx_frames;
err = mlx4_en_set_cq_moder(priv, cq);
