| From fa204fc76c3936c55315ba9423fa7c920af2f9a9 Mon Sep 17 00:00:00 2001 |
| From: Ioana Radulescu <ruxandra.radulescu@nxp.com> |
| Date: Wed, 4 Sep 2019 20:32:56 +0300 |
| Subject: [PATCH] dpaa2-eth: Add congestion group taildrop |
| |
| The increase in number of ingress frame queues means we now risk |
| depleting the buffer pool before the FQ taildrop kicks in. |
| |
| Congestion group taildrop allows us to control the number of frames |
| that can accumulate on a group of Rx frame queues belonging to the |
| same traffic class. |
| |
| This setting coexists with the frame queue based taildrop: whichever |
| limit gets hit first triggers the frame drop. |
| |
| Signed-off-by: Ioana Radulescu <ruxandra.radulescu@nxp.com> |
| --- |
| drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c | 16 ++++++++++++++++ |
| drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h | 9 +++++++++ |
| 2 files changed, 25 insertions(+) |
| |
| --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c |
| +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c |
| @@ -1257,6 +1257,22 @@ static void dpaa2_eth_set_rx_taildrop(st |
| } |
| } |
| |
| + /* Congestion group taildrop: threshold is in frames, per group |
| + * of FQs belonging to the same traffic class |
| + */ |
| + td.threshold = DPAA2_ETH_CG_TAILDROP_THRESH(priv); |
| + td.units = DPNI_CONGESTION_UNIT_FRAMES; |
| + for (i = 0; i < dpaa2_eth_tc_count(priv); i++) { |
| + err = dpni_set_taildrop(priv->mc_io, 0, priv->mc_token, |
| + DPNI_CP_GROUP, DPNI_QUEUE_RX, |
| + i, 0, &td); |
| + if (err) { |
| + netdev_err(priv->net_dev, |
| + "dpni_set_taildrop(CG) failed\n"); |
| + return; |
| + } |
| + } |
| + |
| priv->rx_td_enabled = td.enable; |
| } |
| |
| --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h |
| +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h |
| @@ -56,6 +56,15 @@ |
| #define DPAA2_ETH_REFILL_THRESH \ |
| (DPAA2_ETH_NUM_BUFS - DPAA2_ETH_BUFS_PER_CMD) |
| |
| +/* Congestion group taildrop threshold: number of frames allowed to accumulate |
| + * at any moment in a group of Rx queues belonging to the same traffic class. |
| + * Choose value such that we don't risk depleting the buffer pool before the |
| + * taildrop kicks in |
| + */ |
| +#define DPAA2_ETH_CG_TAILDROP_THRESH(priv) \ |
| + (DPAA2_ETH_MAX_FRAMES_PER_QUEUE * dpaa2_eth_queue_count(priv) / \ |
| + dpaa2_eth_tc_count(priv)) |
| + |
| /* Maximum number of buffers that can be acquired/released through a single |
| * QBMan command |
| */ |