[net-next RFC 1/1] mlx5: Add {get,set}_per_queue_coalesce()

From: Nabil S. Alramli
Date: Wed Aug 23 2023 - 18:47:22 EST

The mlx-5 driver currently only implements querying or modifying coalesce
configurations globally. It does not allow per-queue operations. This
patch is to implement per-queue coalesce operations in the driver.

Signed-off-by: Nabil S. Alramli <dev@xxxxxxxxxxxx>
---
drivers/net/ethernet/mellanox/mlx5/core/en.h | 3 +-
.../ethernet/mellanox/mlx5/core/en_ethtool.c | 212 ++++++++++++++----
.../net/ethernet/mellanox/mlx5/core/en_main.c | 4 +
3 files changed, 173 insertions(+), 46 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h
index c1deb04ba7e8..e61c2fb9bc55 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h
@@ -783,6 +783,7 @@ struct mlx5e_channel {
DECLARE_BITMAP(state, MLX5E_CHANNEL_NUM_STATES);
int ix;
int cpu;
+ struct mlx5e_params params; /* channel specific params */
/* Sync between icosq recovery and XSK enable/disable. */
struct mutex icosq_recovery_lock;
};
@@ -793,7 +794,7 @@ struct mlx5e_channels {
struct mlx5e_channel **c;
struct mlx5e_ptp *ptp;
unsigned int num;
- struct mlx5e_params params;
+ struct mlx5e_params params; /* global params */
};

struct mlx5e_channel_stats {
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
index dff02434ff45..7296ccfc0825 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
@@ -513,33 +513,55 @@ static int mlx5e_set_channels(struct net_device *dev,
return mlx5e_ethtool_set_channels(priv, ch);
}

-int mlx5e_ethtool_get_coalesce(struct mlx5e_priv *priv,
- struct ethtool_coalesce *coal,
- struct kernel_ethtool_coalesce *kernel_coal)
+static int mlx5e_ethtool_get_per_queue_coalesce(struct mlx5e_priv *priv,
+ int queue,
+ struct ethtool_coalesce *coal,
+ struct kernel_ethtool_coalesce *kernel_coal)
{
struct dim_cq_moder *rx_moder, *tx_moder;
+ struct mlx5e_params *params;

if (!MLX5_CAP_GEN(priv->mdev, cq_moderation))
return -EOPNOTSUPP;

- rx_moder = &priv->channels.params.rx_cq_moderation;
+ if (queue != -1 && queue >= priv->channels.num) {
+ netdev_err(priv->netdev, "%s: Invalid queue ID [%d]",
+ __func__, queue);
+ return -EINVAL;
+ }
+
+ if (queue == -1)
+ params = &priv->channels.params;
+ else
+ params = &priv->channels.c[queue]->params;
+
+ rx_moder = &params->rx_cq_moderation;
coal->rx_coalesce_usecs = rx_moder->usec;
coal->rx_max_coalesced_frames = rx_moder->pkts;
- coal->use_adaptive_rx_coalesce = priv->channels.params.rx_dim_enabled;
+ coal->use_adaptive_rx_coalesce = params->rx_dim_enabled;

- tx_moder = &priv->channels.params.tx_cq_moderation;
+ tx_moder = &params->tx_cq_moderation;
coal->tx_coalesce_usecs = tx_moder->usec;
coal->tx_max_coalesced_frames = tx_moder->pkts;
- coal->use_adaptive_tx_coalesce = priv->channels.params.tx_dim_enabled;
+ coal->use_adaptive_tx_coalesce = params->tx_dim_enabled;

- kernel_coal->use_cqe_mode_rx =
- MLX5E_GET_PFLAG(&priv->channels.params, MLX5E_PFLAG_RX_CQE_BASED_MODER);
- kernel_coal->use_cqe_mode_tx =
- MLX5E_GET_PFLAG(&priv->channels.params, MLX5E_PFLAG_TX_CQE_BASED_MODER);
+ if (kernel_coal) {
+ kernel_coal->use_cqe_mode_rx =
+ MLX5E_GET_PFLAG(&priv->channels.params, MLX5E_PFLAG_RX_CQE_BASED_MODER);
+ kernel_coal->use_cqe_mode_tx =
+ MLX5E_GET_PFLAG(&priv->channels.params, MLX5E_PFLAG_TX_CQE_BASED_MODER);
+ }

return 0;
}

+int mlx5e_ethtool_get_coalesce(struct mlx5e_priv *priv,
+ struct ethtool_coalesce *coal,
+ struct kernel_ethtool_coalesce *kernel_coal)
+{
+ return mlx5e_ethtool_get_per_queue_coalesce(priv, -1, coal, kernel_coal);
+}
+
static int mlx5e_get_coalesce(struct net_device *netdev,
struct ethtool_coalesce *coal,
struct kernel_ethtool_coalesce *kernel_coal,
@@ -550,36 +572,76 @@ static int mlx5e_get_coalesce(struct net_device *netdev,
return mlx5e_ethtool_get_coalesce(priv, coal, kernel_coal);
}

+/**
+ * mlx5e_get_per_queue_coalesce - gets coalesce settings for particular queue
+ * @netdev: netdev structure
+ * @coal: ethtool's coalesce settings
+ * @queue: the particular queue to read
+ *
+ * Reads a specific queue's coalesce settings
+ **/
+static int mlx5e_get_per_queue_coalesce(struct net_device *netdev,
+ u32 queue,
+ struct ethtool_coalesce *coal)
+{
+ struct mlx5e_priv *priv = netdev_priv(netdev);
+
+ return mlx5e_ethtool_get_per_queue_coalesce(priv, queue, coal, NULL);
+}
+
#define MLX5E_MAX_COAL_TIME MLX5_MAX_CQ_PERIOD
#define MLX5E_MAX_COAL_FRAMES MLX5_MAX_CQ_COUNT

static void
-mlx5e_set_priv_channels_tx_coalesce(struct mlx5e_priv *priv, struct ethtool_coalesce *coal)
+mlx5e_set_priv_channels_tx_coalesce(struct mlx5e_priv *priv,
+ int queue,
+ struct ethtool_coalesce *coal)
{
struct mlx5_core_dev *mdev = priv->mdev;
int tc;
int i;

- for (i = 0; i < priv->channels.num; ++i) {
- struct mlx5e_channel *c = priv->channels.c[i];
+ if (queue == -1) {
+ for (i = 0; i < priv->channels.num; ++i) {
+ struct mlx5e_channel *c = priv->channels.c[i];
+
+ for (tc = 0; tc < c->num_tc; tc++) {
+ mlx5_core_modify_cq_moderation(mdev,
+ &c->sq[tc].cq.mcq,
+ coal->tx_coalesce_usecs,
+ coal->tx_max_coalesced_frames);
+ }
+ }
+ } else {
+ struct mlx5e_channel *c = priv->channels.c[queue];

for (tc = 0; tc < c->num_tc; tc++) {
mlx5_core_modify_cq_moderation(mdev,
- &c->sq[tc].cq.mcq,
- coal->tx_coalesce_usecs,
- coal->tx_max_coalesced_frames);
+ &c->sq[tc].cq.mcq,
+ coal->tx_coalesce_usecs,
+ coal->tx_max_coalesced_frames);
}
}
}

static void
-mlx5e_set_priv_channels_rx_coalesce(struct mlx5e_priv *priv, struct ethtool_coalesce *coal)
+mlx5e_set_priv_channels_rx_coalesce(struct mlx5e_priv *priv,
+ int queue,
+ struct ethtool_coalesce *coal)
{
struct mlx5_core_dev *mdev = priv->mdev;
int i;

- for (i = 0; i < priv->channels.num; ++i) {
- struct mlx5e_channel *c = priv->channels.c[i];
+ if (queue == -1) {
+ for (i = 0; i < priv->channels.num; ++i) {
+ struct mlx5e_channel *c = priv->channels.c[i];
+
+ mlx5_core_modify_cq_moderation(mdev, &c->rq.cq.mcq,
+ coal->rx_coalesce_usecs,
+ coal->rx_max_coalesced_frames);
+ }
+ } else {
+ struct mlx5e_channel *c = priv->channels.c[queue];

mlx5_core_modify_cq_moderation(mdev, &c->rq.cq.mcq,
coal->rx_coalesce_usecs,
@@ -596,15 +658,17 @@ static int cqe_mode_to_period_mode(bool val)
return val ? MLX5_CQ_PERIOD_MODE_START_FROM_CQE : MLX5_CQ_PERIOD_MODE_START_FROM_EQE;
}

-int mlx5e_ethtool_set_coalesce(struct mlx5e_priv *priv,
- struct ethtool_coalesce *coal,
- struct kernel_ethtool_coalesce *kernel_coal,
- struct netlink_ext_ack *extack)
+static int mlx5e_ethtool_set_per_queue_coalesce(struct mlx5e_priv *priv,
+ int queue,
+ struct ethtool_coalesce *coal,
+ struct kernel_ethtool_coalesce *kernel_coal,
+ struct netlink_ext_ack *extack)
{
struct dim_cq_moder *rx_moder, *tx_moder;
struct mlx5_core_dev *mdev = priv->mdev;
- struct mlx5e_params new_params;
- bool reset_rx, reset_tx;
+ bool reset_rx = false, reset_tx = false;
+ struct mlx5e_params new_params = {0};
+ struct mlx5e_params *old_params;
bool reset = true;
u8 cq_period_mode;
int err = 0;
@@ -626,14 +690,29 @@ int mlx5e_ethtool_set_coalesce(struct mlx5e_priv *priv,
return -ERANGE;
}

- if ((kernel_coal->use_cqe_mode_rx || kernel_coal->use_cqe_mode_tx) &&
- !MLX5_CAP_GEN(priv->mdev, cq_period_start_from_cqe)) {
- NL_SET_ERR_MSG_MOD(extack, "cqe_mode_rx/tx is not supported on this device");
- return -EOPNOTSUPP;
+ if (kernel_coal) {
+ if ((kernel_coal->use_cqe_mode_rx || kernel_coal->use_cqe_mode_tx) &&
+ !MLX5_CAP_GEN(priv->mdev, cq_period_start_from_cqe)) {
+ NL_SET_ERR_MSG_MOD(extack,
+ "cqe_mode_rx/tx is not supported on this device");
+ return -EOPNOTSUPP;
+ }
+ }
+
+ if (queue != -1 && queue >= priv->channels.num) {
+ netdev_err(priv->netdev, "%s: Invalid queue ID [%d]",
+ __func__, queue);
+ return -EINVAL;
}

mutex_lock(&priv->state_lock);
- new_params = priv->channels.params;
+
+ if (queue == -1)
+ old_params = &priv->channels.params;
+ else
+ old_params = &priv->channels.c[queue]->params;
+
+ new_params = *old_params;

rx_moder = &new_params.rx_cq_moderation;
rx_moder->usec = coal->rx_coalesce_usecs;
@@ -645,19 +724,21 @@ int mlx5e_ethtool_set_coalesce(struct mlx5e_priv *priv,
tx_moder->pkts = coal->tx_max_coalesced_frames;
new_params.tx_dim_enabled = !!coal->use_adaptive_tx_coalesce;

- reset_rx = !!coal->use_adaptive_rx_coalesce != priv->channels.params.rx_dim_enabled;
- reset_tx = !!coal->use_adaptive_tx_coalesce != priv->channels.params.tx_dim_enabled;
+ reset_rx = !!coal->use_adaptive_rx_coalesce != old_params->rx_dim_enabled;
+ reset_tx = !!coal->use_adaptive_tx_coalesce != old_params->tx_dim_enabled;

- cq_period_mode = cqe_mode_to_period_mode(kernel_coal->use_cqe_mode_rx);
- if (cq_period_mode != rx_moder->cq_period_mode) {
- mlx5e_set_rx_cq_mode_params(&new_params, cq_period_mode);
- reset_rx = true;
- }
+ if (kernel_coal) {
+ cq_period_mode = cqe_mode_to_period_mode(kernel_coal->use_cqe_mode_rx);
+ if (cq_period_mode != rx_moder->cq_period_mode) {
+ mlx5e_set_rx_cq_mode_params(&new_params, cq_period_mode);
+ reset_rx = true;
+ }

- cq_period_mode = cqe_mode_to_period_mode(kernel_coal->use_cqe_mode_tx);
- if (cq_period_mode != tx_moder->cq_period_mode) {
- mlx5e_set_tx_cq_mode_params(&new_params, cq_period_mode);
- reset_tx = true;
+ cq_period_mode = cqe_mode_to_period_mode(kernel_coal->use_cqe_mode_tx);
+ if (cq_period_mode != tx_moder->cq_period_mode) {
+ mlx5e_set_tx_cq_mode_params(&new_params, cq_period_mode);
+ reset_tx = true;
+ }
}

if (reset_rx) {
@@ -678,18 +759,40 @@ int mlx5e_ethtool_set_coalesce(struct mlx5e_priv *priv,
*/
if (!reset_rx && !reset_tx && test_bit(MLX5E_STATE_OPENED, &priv->state)) {
if (!coal->use_adaptive_rx_coalesce)
- mlx5e_set_priv_channels_rx_coalesce(priv, coal);
+ mlx5e_set_priv_channels_rx_coalesce(priv, queue, coal);
if (!coal->use_adaptive_tx_coalesce)
- mlx5e_set_priv_channels_tx_coalesce(priv, coal);
+ mlx5e_set_priv_channels_tx_coalesce(priv, queue, coal);
reset = false;
}

- err = mlx5e_safe_switch_params(priv, &new_params, NULL, NULL, reset);
+ if (queue == -1) {
+ err = mlx5e_safe_switch_params(priv, &new_params, NULL, NULL, reset);
+ } else {
+ if (reset) {
+ netdev_err(priv->netdev, "%s: Per-queue adaptive-rx / adaptive-tx operations are not supported",
+ __func__);
+ err = -EOPNOTSUPP;
+ } else {
+ /* Since preactivate is NULL and we are not doing reset we just copy the
+ * params here instead of calling mlx5e_safe_switch_params() to avoid
+ * having to pass the queue to it.
+ */
+ priv->channels.c[queue]->params = new_params;
+ }
+ }

mutex_unlock(&priv->state_lock);
return err;
}

+int mlx5e_ethtool_set_coalesce(struct mlx5e_priv *priv,
+ struct ethtool_coalesce *coal,
+ struct kernel_ethtool_coalesce *kernel_coal,
+ struct netlink_ext_ack *extack)
+{
+ return mlx5e_ethtool_set_per_queue_coalesce(priv, -1, coal, kernel_coal, extack);
+}
+
static int mlx5e_set_coalesce(struct net_device *netdev,
struct ethtool_coalesce *coal,
struct kernel_ethtool_coalesce *kernel_coal,
@@ -700,6 +803,23 @@ static int mlx5e_set_coalesce(struct net_device *netdev,
return mlx5e_ethtool_set_coalesce(priv, coal, kernel_coal, extack);
}

+/**
+ * mlx5e_set_per_queue_coalesce - set specific queue's coalesce settings
+ * @netdev: the netdev to change
+ * @coal: ethtool's coalesce settings
+ * @queue: the queue to change
+ *
+ * Sets the specified queue's coalesce settings.
+ **/
+static int mlx5e_set_per_queue_coalesce(struct net_device *netdev,
+ u32 queue,
+ struct ethtool_coalesce *coal)
+{
+ struct mlx5e_priv *priv = netdev_priv(netdev);
+
+ return mlx5e_ethtool_set_per_queue_coalesce(priv, queue, coal, NULL, NULL);
+}
+
static void ptys2ethtool_supported_link(struct mlx5_core_dev *mdev,
unsigned long *supported_modes,
u32 eth_proto_cap)
@@ -2434,6 +2554,8 @@ const struct ethtool_ops mlx5e_ethtool_ops = {
.flash_device = mlx5e_flash_device,
.get_priv_flags = mlx5e_get_priv_flags,
.set_priv_flags = mlx5e_set_priv_flags,
+ .get_per_queue_coalesce = mlx5e_get_per_queue_coalesce,
+ .set_per_queue_coalesce = mlx5e_set_per_queue_coalesce,
.self_test = mlx5e_self_test,
.get_fec_stats = mlx5e_get_fec_stats,
.get_fecparam = mlx5e_get_fecparam,
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index a2ae791538ed..4fce06ca57bc 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -3043,6 +3043,7 @@ int mlx5e_safe_switch_params(struct mlx5e_priv *priv,
{
struct mlx5e_channels *new_chs;
int err;
+ int i;

reset &= test_bit(MLX5E_STATE_OPENED, &priv->state);
if (!reset)
@@ -3059,6 +3060,9 @@ int mlx5e_safe_switch_params(struct mlx5e_priv *priv,
if (err)
goto err_cancel_selq;

+ for (i = 0; i < new_chs->num; ++i)
+ new_chs->c[i]->params = *params;
+
err = mlx5e_switch_priv_channels(priv, new_chs, preactivate, context);
if (err)
goto err_close;
--
2.35.1