[PATCH net-next v7 1/4] ethtool: Track user-provided RSS indirection table size
From: Björn Töpel <bjorn@kernel.org>
Date: 2026-03-20 08:58:37
Also in:
linux-rdma, lkml, netdev
Subsystem:
broadcom bnxt_en 50 gigabit ethernet driver, mellanox ethernet driver (mlx5e), mellanox mlx5 core vpi driver, networking drivers, networking [ethtool], networking [general], the rest · Maintainers:
Michael Chan, Pavan Chebbi, Saeed Mahameed, Tariq Toukan, Mark Bloch, Leon Romanovsky, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Track the number of indirection table entries the user originally provided (context 0/default as well!). Replace IFF_RXFH_CONFIGURED with rss_indir_user_size: the flag is redundant now that user_size captures the same information. Add ethtool_rxfh_indir_lost() for drivers that must reset the indirection table. Convert bnxt and mlx5 to use it. Signed-off-by: Björn Töpel <bjorn@kernel.org> --- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 3 +- .../net/ethernet/mellanox/mlx5/core/en_main.c | 21 ++++++++------ include/linux/ethtool.h | 7 +++++ include/linux/netdevice.h | 7 +---- net/ethtool/common.c | 28 +++++++++++++++++++ net/ethtool/ioctl.c | 9 +++--- net/ethtool/rss.c | 24 ++++++++++------ 7 files changed, 70 insertions(+), 29 deletions(-)
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 604966a398f5..84eb53b4172b 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c@@ -8118,8 +8118,7 @@ static int __bnxt_reserve_rings(struct bnxt *bp) (bnxt_get_nr_rss_ctxs(bp, bp->rx_nr_rings) != bnxt_get_nr_rss_ctxs(bp, rx_rings) || bnxt_get_max_rss_ring(bp) >= rx_rings)) { - netdev_warn(bp->dev, "RSS table entries reverting to default\n"); - bp->dev->priv_flags &= ~IFF_RXFH_CONFIGURED; + ethtool_rxfh_indir_lost(bp->dev); } } bp->rx_nr_rings = rx_rings;
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index f7009da94f0b..4429b4058daa 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c@@ -6483,12 +6483,23 @@ int mlx5e_attach_netdev(struct mlx5e_priv *priv) /* max number of channels may have changed */ max_nch = mlx5e_calc_max_nch(priv->mdev, priv->netdev, profile); + + /* Locking is required by ethtool_rxfh_indir_lost() (sends + * ETHTOOL_MSG_RSS_NTF) and by netif_set_real_num_*_queues in case + * the netdev has been registered by this point (if this function + * was called in the reload or resume flow). + */ + if (need_lock) { + rtnl_lock(); + netdev_lock(priv->netdev); + } + if (priv->channels.params.num_channels > max_nch) { mlx5_core_warn(priv->mdev, "MLX5E: Reducing number of channels to %d\n", max_nch); /* Reducing the number of channels - RXFH has to be reset, and * mlx5e_num_channels_changed below will build the RQT. */ - priv->netdev->priv_flags &= ~IFF_RXFH_CONFIGURED; + ethtool_rxfh_indir_lost(priv->netdev); priv->channels.params.num_channels = max_nch; if (priv->channels.params.mqprio.mode == TC_MQPRIO_MODE_CHANNEL) { mlx5_core_warn(priv->mdev, "MLX5E: Disabling MQPRIO channel mode\n");
@@ -6505,15 +6516,7 @@ int mlx5e_attach_netdev(struct mlx5e_priv *priv) /* 1. Set the real number of queues in the kernel the first time. * 2. Set our default XPS cpumask. * 3. Build the RQT. - * - * Locking is required by netif_set_real_num_*_queues in case the - * netdev has been registered by this point (if this function was called - * in the reload or resume flow). */ - if (need_lock) { - rtnl_lock(); - netdev_lock(priv->netdev); - } err = mlx5e_num_channels_changed(priv); if (need_lock) { netdev_unlock(priv->netdev);
diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index 656d465bcd06..34ca9261de82 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h@@ -176,6 +176,8 @@ static inline u32 ethtool_rxfh_indir_default(u32 index, u32 n_rx_rings) * struct ethtool_rxfh_context - a custom RSS context configuration * @indir_size: Number of u32 entries in indirection table * @key_size: Size of hash key, in bytes + * @indir_user_size: number of user provided entries for the + * indirection table * @priv_size: Size of driver private data, in bytes * @hfunc: RSS hash function identifier. One of the %ETH_RSS_HASH_* * @input_xfrm: Defines how the input data is transformed. Valid values are one
@@ -186,6 +188,7 @@ static inline u32 ethtool_rxfh_indir_default(u32 index, u32 n_rx_rings) struct ethtool_rxfh_context { u32 indir_size; u32 key_size; + u32 indir_user_size; u16 priv_size; u8 hfunc; u8 input_xfrm;
@@ -214,6 +217,7 @@ static inline u8 *ethtool_rxfh_context_key(struct ethtool_rxfh_context *ctx) } void ethtool_rxfh_context_lost(struct net_device *dev, u32 context_id); +void ethtool_rxfh_indir_lost(struct net_device *dev); struct link_mode_info { int speed;
@@ -1337,12 +1341,15 @@ int ethtool_virtdev_set_link_ksettings(struct net_device *dev, * @rss_ctx: XArray of custom RSS contexts * @rss_lock: Protects entries in @rss_ctx. May be taken from * within RTNL. + * @rss_indir_user_size: Number of user provided entries for the default + * (context 0) indirection table. * @wol_enabled: Wake-on-LAN is enabled * @module_fw_flash_in_progress: Module firmware flashing is in progress. */ struct ethtool_netdev_state { struct xarray rss_ctx; struct mutex rss_lock; + u32 rss_indir_user_size; unsigned wol_enabled:1; unsigned module_fw_flash_in_progress:1; };
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 7ca01eb3f7d2..e82de6831e05 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h@@ -1716,7 +1716,6 @@ struct net_device_ops { * @IFF_OPENVSWITCH: device is a Open vSwitch master * @IFF_L3MDEV_SLAVE: device is enslaved to an L3 master device * @IFF_TEAM: device is a team device - * @IFF_RXFH_CONFIGURED: device has had Rx Flow indirection table configured * @IFF_PHONY_HEADROOM: the headroom value is controlled by an external * entity (i.e. the master device for bridged veth) * @IFF_MACSEC: device is a MACsec device
@@ -1752,7 +1751,6 @@ enum netdev_priv_flags { IFF_OPENVSWITCH = 1<<20, IFF_L3MDEV_SLAVE = 1<<21, IFF_TEAM = 1<<22, - IFF_RXFH_CONFIGURED = 1<<23, IFF_PHONY_HEADROOM = 1<<24, IFF_MACSEC = 1<<25, IFF_NO_RX_HANDLER = 1<<26,
@@ -5569,10 +5567,7 @@ static inline bool netif_is_lag_port(const struct net_device *dev) return netif_is_bond_slave(dev) || netif_is_team_port(dev); } -static inline bool netif_is_rxfh_configured(const struct net_device *dev) -{ - return dev->priv_flags & IFF_RXFH_CONFIGURED; -} +bool netif_is_rxfh_configured(const struct net_device *dev); static inline bool netif_is_failover(const struct net_device *dev) {
diff --git a/net/ethtool/common.c b/net/ethtool/common.c
index e252cf20c22f..d7d832fa9e00 100644
--- a/net/ethtool/common.c
+++ b/net/ethtool/common.c@@ -1204,6 +1204,34 @@ void ethtool_rxfh_context_lost(struct net_device *dev, u32 context_id) } EXPORT_SYMBOL(ethtool_rxfh_context_lost); +bool netif_is_rxfh_configured(const struct net_device *dev) +{ + return dev->ethtool->rss_indir_user_size; +} +EXPORT_SYMBOL(netif_is_rxfh_configured); + +/** + * ethtool_rxfh_indir_lost - Notify core that the RSS indirection table was lost + * @dev: network device + * + * Drivers should call this when the device can no longer maintain the + * user-configured indirection table, typically after a HW fault recovery + * that reduced the maximum queue count. Marks the default RSS context + * indirection table as unconfigured and sends an %ETHTOOL_MSG_RSS_NTF + * notification. + */ +void ethtool_rxfh_indir_lost(struct net_device *dev) +{ + WARN_ONCE(!rtnl_is_locked() && + !lockdep_is_held_type(&dev->ethtool->rss_lock, -1), + "RSS context lock assertion failed\n"); + + netdev_err(dev, "device error, RSS indirection table lost\n"); + dev->ethtool->rss_indir_user_size = 0; + ethtool_rss_notify(dev, ETHTOOL_MSG_RSS_NTF, 0); +} +EXPORT_SYMBOL(ethtool_rxfh_indir_lost); + enum ethtool_link_medium ethtool_str_to_medium(const char *str) { int i;
diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c
index ff4b4780d6af..3d31a5a041e3 100644
--- a/net/ethtool/ioctl.c
+++ b/net/ethtool/ioctl.c@@ -1404,9 +1404,9 @@ static noinline_for_stack int ethtool_set_rxfh_indir(struct net_device *dev, /* indicate whether rxfh was set to default */ if (user_size == 0) - dev->priv_flags &= ~IFF_RXFH_CONFIGURED; + dev->ethtool->rss_indir_user_size = 0; else - dev->priv_flags |= IFF_RXFH_CONFIGURED; + dev->ethtool->rss_indir_user_size = rxfh_dev.indir_size; out_unlock: mutex_unlock(&dev->ethtool->rss_lock);
@@ -1721,9 +1721,9 @@ static noinline_for_stack int ethtool_set_rxfh(struct net_device *dev, if (!rxfh_dev.rss_context) { /* indicate whether rxfh was set to default */ if (rxfh.indir_size == 0) - dev->priv_flags &= ~IFF_RXFH_CONFIGURED; + dev->ethtool->rss_indir_user_size = 0; else if (rxfh.indir_size != ETH_RXFH_INDIR_NO_CHANGE) - dev->priv_flags |= IFF_RXFH_CONFIGURED; + dev->ethtool->rss_indir_user_size = dev_indir_size; } /* Update rss_ctx tracking */ if (rxfh_dev.rss_delete) {
@@ -1736,6 +1736,7 @@ static noinline_for_stack int ethtool_set_rxfh(struct net_device *dev, ctx->indir_configured = rxfh.indir_size && rxfh.indir_size != ETH_RXFH_INDIR_NO_CHANGE; + ctx->indir_user_size = dev_indir_size; } if (rxfh_dev.key) { memcpy(ethtool_rxfh_context_key(ctx), rxfh_dev.key,
diff --git a/net/ethtool/rss.c b/net/ethtool/rss.c
index da5934cceb07..e6fc6e64fb27 100644
--- a/net/ethtool/rss.c
+++ b/net/ethtool/rss.c@@ -686,7 +686,7 @@ rss_set_prep_indir(struct net_device *dev, struct genl_info *info, *mod |= memcmp(rxfh->indir, data->indir_table, data->indir_size); - return 0; + return user_size; err_free: kfree(rxfh->indir);
@@ -833,6 +833,7 @@ ethnl_rss_set(struct ethnl_req_info *req_info, struct genl_info *info) struct nlattr **tb = info->attrs; struct rss_reply_data data = {}; const struct ethtool_ops *ops; + u32 indir_user_size; int ret; ops = dev->ethtool_ops;
@@ -845,8 +846,9 @@ ethnl_rss_set(struct ethnl_req_info *req_info, struct genl_info *info) rxfh.rss_context = request->rss_context; ret = rss_set_prep_indir(dev, info, &data, &rxfh, &indir_reset, &mod); - if (ret) + if (ret < 0) goto exit_clean_data; + indir_user_size = ret; indir_mod = !!tb[ETHTOOL_A_RSS_INDIR]; rxfh.hfunc = data.hfunc;
@@ -889,12 +891,15 @@ ethnl_rss_set(struct ethnl_req_info *req_info, struct genl_info *info) if (ret) goto exit_unlock; - if (ctx) + if (ctx) { rss_set_ctx_update(ctx, tb, &data, &rxfh); - else if (indir_reset) - dev->priv_flags &= ~IFF_RXFH_CONFIGURED; - else if (indir_mod) - dev->priv_flags |= IFF_RXFH_CONFIGURED; + if (indir_user_size) + ctx->indir_user_size = indir_user_size; + } else if (indir_reset) { + dev->ethtool->rss_indir_user_size = 0; + } else if (indir_mod) { + dev->ethtool->rss_indir_user_size = indir_user_size; + } exit_unlock: mutex_unlock(&dev->ethtool->rss_lock);
@@ -999,6 +1004,7 @@ int ethnl_rss_create_doit(struct sk_buff *skb, struct genl_info *info) const struct ethtool_ops *ops; struct rss_req_info req = {}; struct net_device *dev; + u32 indir_user_size; struct sk_buff *rsp; void *hdr; u32 limit;
@@ -1035,8 +1041,9 @@ int ethnl_rss_create_doit(struct sk_buff *skb, struct genl_info *info) goto exit_ops; ret = rss_set_prep_indir(dev, info, &data, &rxfh, &indir_dflt, &mod); - if (ret) + if (ret < 0) goto exit_clean_data; + indir_user_size = ret; ethnl_update_u8(&rxfh.hfunc, tb[ETHTOOL_A_RSS_HFUNC], &mod);
@@ -1080,6 +1087,7 @@ int ethnl_rss_create_doit(struct sk_buff *skb, struct genl_info *info) /* Store the config from rxfh to Xarray.. */ rss_set_ctx_update(ctx, tb, &data, &rxfh); + ctx->indir_user_size = indir_user_size; /* .. copy from Xarray to data. */ __rss_prepare_ctx(dev, &data, ctx);
--
2.53.0