@@ -414,6 +414,26 @@ attribute-sets:
name: combined-count
type: u32
+ -
+ name: irq-moderation
+ attributes:
+ -
+ name: usec
+ type: u32
+ -
+ name: pkts
+ type: u32
+ -
+ name: comps
+ type: u32
+ -
+ name: profile
+ attributes:
+ -
+ name: irq-moderation
+ type: nest
+ multi-attr: true
+ nested-attributes: irq-moderation
-
name: coalesce
attributes:
@@ -502,6 +522,15 @@ attribute-sets:
-
name: tx-aggr-time-usecs
type: u32
+ -
+ name: rx-profile
+ type: nest
+ nested-attributes: profile
+ -
+ name: tx-profile
+ type: nest
+ nested-attributes: profile
+
-
name: pause-stat
attributes:
@@ -1325,6 +1354,8 @@ operations:
- tx-aggr-max-bytes
- tx-aggr-max-frames
- tx-aggr-time-usecs
+ - rx-profile
+ - tx-profile
dump: *coalesce-get-op
-
name: coalesce-set
@@ -1040,6 +1040,8 @@ Kernel response contents:
``ETHTOOL_A_COALESCE_TX_AGGR_MAX_BYTES`` u32 max aggr size, Tx
``ETHTOOL_A_COALESCE_TX_AGGR_MAX_FRAMES`` u32 max aggr packets, Tx
``ETHTOOL_A_COALESCE_TX_AGGR_TIME_USECS`` u32 time (us), aggr, Tx
+ ``ETHTOOL_A_COALESCE_RX_PROFILE`` nested profile of DIM, Rx
+ ``ETHTOOL_A_COALESCE_TX_PROFILE`` nested profile of DIM, Tx
=========================================== ====== =======================
Attributes are only included in reply if their value is not zero or the
@@ -1105,6 +1107,8 @@ Request contents:
``ETHTOOL_A_COALESCE_TX_AGGR_MAX_BYTES`` u32 max aggr size, Tx
``ETHTOOL_A_COALESCE_TX_AGGR_MAX_FRAMES`` u32 max aggr packets, Tx
``ETHTOOL_A_COALESCE_TX_AGGR_TIME_USECS`` u32 time (us), aggr, Tx
+ ``ETHTOOL_A_COALESCE_RX_PROFILE`` nested profile of DIM, Rx
+ ``ETHTOOL_A_COALESCE_TX_PROFILE`` nested profile of DIM, Tx
=========================================== ====== =======================
Request is rejected if it attributes declared as unsupported by driver (i.e.
@@ -169,6 +169,48 @@ usage is not complete but it should make the outline of the usage clear.
...
}
+
+Tuning DIM
+==========
+
+Net DIM serves a range of network devices and delivers excellent acceleration
+benefits. Yet, it has been observed that some preset configurations of DIM may
+not align seamlessly with the varying specifications of network devices, and
+this discrepancy has been identified as a factor to the suboptimal performance
+outcomes of DIM-enabled network devices, related to a mismatch in profiles.
+
+To address this issue, Net DIM introduces a per-device control to modify and
+access a device's ``rx-profile`` and ``tx-profile`` parameters:
+Assume that the target network device is named ethx, and ethx only declares
+support for RX profile setting and supports modification of ``usec`` field
+and ``pkts`` field (See the data structure:
+:c:type:`struct dim_cq_moder <dim_cq_moder>`).
+
+You can use ethtool to modify the current RX DIM profile where all
+values are 64::
+
+ $ ethtool -C ethx rx-profile 1,1,n_2,2,n_3,n,n_n,4,n_n,n,n
+
+``n`` means do not modify this field, and ``_`` separates structure
+elements of the profile array.
+
+Querying the current profiles using::
+
+ $ ethtool -c ethx
+ ...
+ rx-profile:
+ {.usec = 1, .pkts = 1, .comps = n/a,},
+ {.usec = 2, .pkts = 2, .comps = n/a,},
+ {.usec = 3, .pkts = 64, .comps = n/a,},
+ {.usec = 64, .pkts = 4, .comps = n/a,},
+ {.usec = 64, .pkts = 64, .comps = n/a,}
+ tx-profile: n/a
+
+If the network device does not support specific fields of DIM profiles,
+the corresponding ``n/a`` will display. If the ``n/a`` field is being
+modified, error messages will be reported.
+
+
Dynamic Interrupt Moderation (DIM) library API
==============================================
@@ -10,6 +10,8 @@
#include <linux/types.h>
#include <linux/workqueue.h>
+struct net_device;
+
/* Number of DIM profiles and period mode. */
#define NET_DIM_PARAMS_NUM_PROFILES 5
#define NET_DIM_DEFAULT_RX_CQ_PKTS_FROM_EQE 256
@@ -45,12 +47,45 @@
* @pkts: CQ packet counter suggestion (by DIM)
* @comps: Completion counter
* @cq_period_mode: CQ period count mode (from CQE/EQE)
+ * @rcu: for asynchronous kfree_rcu
*/
struct dim_cq_moder {
u16 usec;
u16 pkts;
u16 comps;
u8 cq_period_mode;
+ struct rcu_head rcu;
+};
+
+#define DIM_PROFILE_RX BIT(0) /* support rx profile modification */
+#define DIM_PROFILE_TX BIT(1) /* support tx profile modification */
+
+#define DIM_COALESCE_USEC BIT(0) /* support usec field modification */
+#define DIM_COALESCE_PKTS BIT(1) /* support pkts field modification */
+#define DIM_COALESCE_COMPS BIT(2) /* support comps field modification */
+
+/**
+ * struct dim_irq_moder - Structure for irq moderation information.
+ * Used to collect irq moderation related information.
+ *
+ * @profile_flags: DIM_PROFILE_*
+ * @coal_flags: DIM_COALESCE_* for Rx and Tx
+ * @dim_rx_mode: Rx DIM period count mode: CQE or EQE
+ * @dim_tx_mode: Tx DIM period count mode: CQE or EQE
+ * @rx_profile: DIM profile list for Rx
+ * @tx_profile: DIM profile list for Tx
+ * @rx_dim_work: Rx DIM worker scheduled by net_dim()
+ * @tx_dim_work: Tx DIM worker scheduled by net_dim()
+ */
+struct dim_irq_moder {
+ u8 profile_flags;
+ u8 coal_flags;
+ u8 dim_rx_mode;
+ u8 dim_tx_mode;
+ struct dim_cq_moder __rcu *rx_profile;
+ struct dim_cq_moder __rcu *tx_profile;
+ void (*rx_dim_work)(struct work_struct *work);
+ void (*tx_dim_work)(struct work_struct *work);
};
/**
@@ -198,6 +233,29 @@ enum dim_step_result {
DIM_ON_EDGE,
};
+/**
+ * net_dim_init_irq_moder - collect information to initialize irq moderation
+ * @dev: target network device
+ * @profile_flags: Rx or Tx profile modification capability
+ * @coal_flags: irq moderation params flags
+ * @rx_mode: CQ period mode for Rx
+ * @tx_mode: CQ period mode for Tx
+ * @rx_dim_work: Rx worker called after dim decision
+ * @tx_dim_work: Tx worker called after dim decision
+ *
+ * Return: 0 on success or a negative error code.
+ */
+int net_dim_init_irq_moder(struct net_device *dev, u8 profile_flags,
+ u8 coal_flags, u8 rx_mode, u8 tx_mode,
+ void (*rx_dim_work)(struct work_struct *work),
+ void (*tx_dim_work)(struct work_struct *work));
+
+/**
+ * net_dim_free_irq_moder - free fields for irq moderation
+ * @dev: target network device
+ */
+void net_dim_free_irq_moder(struct net_device *dev);
+
/**
* dim_on_top - check if current state is a good place to stop (top location)
* @dim: DIM context
@@ -284,7 +284,9 @@ bool ethtool_convert_link_mode_to_legacy_u32(u32 *legacy_u32,
#define ETHTOOL_COALESCE_TX_AGGR_MAX_BYTES BIT(24)
#define ETHTOOL_COALESCE_TX_AGGR_MAX_FRAMES BIT(25)
#define ETHTOOL_COALESCE_TX_AGGR_TIME_USECS BIT(26)
-#define ETHTOOL_COALESCE_ALL_PARAMS GENMASK(26, 0)
+#define ETHTOOL_COALESCE_RX_PROFILE BIT(27)
+#define ETHTOOL_COALESCE_TX_PROFILE BIT(28)
+#define ETHTOOL_COALESCE_ALL_PARAMS GENMASK(28, 0)
#define ETHTOOL_COALESCE_USECS \
(ETHTOOL_COALESCE_RX_USECS | ETHTOOL_COALESCE_TX_USECS)
@@ -2403,6 +2403,9 @@ struct net_device {
/** @page_pools: page pools created for this netdevice */
struct hlist_head page_pools;
#endif
+
+ /** @irq_moder: dim parameters used if IS_ENABLED(CONFIG_DIMLIB). */
+ struct dim_irq_moder *irq_moder;
};
#define to_net_dev(d) container_of(d, struct net_device, dev)
@@ -416,12 +416,34 @@ enum {
ETHTOOL_A_COALESCE_TX_AGGR_MAX_BYTES, /* u32 */
ETHTOOL_A_COALESCE_TX_AGGR_MAX_FRAMES, /* u32 */
ETHTOOL_A_COALESCE_TX_AGGR_TIME_USECS, /* u32 */
+ /* nest - _A_PROFILE_IRQ_MODERATION */
+ ETHTOOL_A_COALESCE_RX_PROFILE,
+ /* nest - _A_PROFILE_IRQ_MODERATION */
+ ETHTOOL_A_COALESCE_TX_PROFILE,
/* add new constants above here */
__ETHTOOL_A_COALESCE_CNT,
ETHTOOL_A_COALESCE_MAX = (__ETHTOOL_A_COALESCE_CNT - 1)
};
+enum {
+ ETHTOOL_A_PROFILE_UNSPEC,
+ /* nest, _A_IRQ_MODERATION_* */
+ ETHTOOL_A_PROFILE_IRQ_MODERATION,
+ __ETHTOOL_A_PROFILE_CNT,
+ ETHTOOL_A_PROFILE_MAX = (__ETHTOOL_A_PROFILE_CNT - 1)
+};
+
+enum {
+ ETHTOOL_A_IRQ_MODERATION_UNSPEC,
+ ETHTOOL_A_IRQ_MODERATION_USEC, /* u32 */
+ ETHTOOL_A_IRQ_MODERATION_PKTS, /* u32 */
+ ETHTOOL_A_IRQ_MODERATION_COMPS, /* u32 */
+
+ __ETHTOOL_A_IRQ_MODERATION_CNT,
+ ETHTOOL_A_IRQ_MODERATION_MAX = (__ETHTOOL_A_IRQ_MODERATION_CNT - 1)
+};
+
/* PAUSE */
enum {
@@ -4,6 +4,7 @@
*/
#include <linux/dim.h>
+#include <linux/rtnetlink.h>
/*
* Net DIM profiles:
@@ -95,6 +96,75 @@ net_dim_get_def_tx_moderation(u8 cq_period_mode)
}
EXPORT_SYMBOL(net_dim_get_def_tx_moderation);
+int net_dim_init_irq_moder(struct net_device *dev, u8 profile_flags,
+ u8 coal_flags, u8 rx_mode, u8 tx_mode,
+ void (*rx_dim_work)(struct work_struct *work),
+ void (*tx_dim_work)(struct work_struct *work))
+{
+ struct dim_cq_moder *rxp = NULL, *txp;
+ struct dim_irq_moder *moder;
+ int len;
+
+ dev->irq_moder = kzalloc(sizeof(*dev->irq_moder), GFP_KERNEL);
+ if (!dev->irq_moder)
+ return -ENOMEM;
+
+ moder = dev->irq_moder;
+ len = NET_DIM_PARAMS_NUM_PROFILES * sizeof(*moder->rx_profile);
+
+ moder->coal_flags = coal_flags;
+ moder->profile_flags = profile_flags;
+
+ if (profile_flags & DIM_PROFILE_RX) {
+ moder->rx_dim_work = rx_dim_work;
+ moder->dim_rx_mode = rx_mode;
+ rxp = kmemdup(rx_profile[rx_mode], len, GFP_KERNEL);
+ if (!rxp)
+ goto free_moder;
+
+ rcu_assign_pointer(moder->rx_profile, rxp);
+ }
+
+ if (profile_flags & DIM_PROFILE_TX) {
+ moder->tx_dim_work = tx_dim_work;
+ moder->dim_tx_mode = tx_mode;
+ txp = kmemdup(tx_profile[tx_mode], len, GFP_KERNEL);
+ if (!txp)
+ goto free_rxp;
+
+ rcu_assign_pointer(moder->tx_profile, txp);
+ }
+
+ return 0;
+
+free_rxp:
+ kfree(rxp);
+free_moder:
+ kfree(moder);
+ return -ENOMEM;
+}
+EXPORT_SYMBOL(net_dim_init_irq_moder);
+
+/* RTNL lock is held. */
+void net_dim_free_irq_moder(struct net_device *dev)
+{
+ struct dim_cq_moder *rxp, *txp;
+
+ if (!dev->irq_moder)
+ return;
+
+ rxp = rtnl_dereference(dev->irq_moder->rx_profile);
+ txp = rtnl_dereference(dev->irq_moder->tx_profile);
+
+ rcu_assign_pointer(dev->irq_moder->rx_profile, NULL);
+ rcu_assign_pointer(dev->irq_moder->tx_profile, NULL);
+
+ kfree_rcu(rxp, rcu);
+ kfree_rcu(txp, rcu);
+ kfree(dev->irq_moder);
+}
+EXPORT_SYMBOL(net_dim_free_irq_moder);
+
static int net_dim_step(struct dim *dim)
{
if (dim->tired == (NET_DIM_PARAMS_NUM_PROFILES * 2))
@@ -502,6 +502,7 @@ config FAILOVER
config ETHTOOL_NETLINK
bool "Netlink interface for ethtool"
+ select DIMLIB
default y
help
An alternative userspace interface for ethtool based on generic
@@ -1,5 +1,6 @@
// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/dim.h>
#include "netlink.h"
#include "common.h"
@@ -82,6 +83,14 @@ static int coalesce_prepare_data(const struct ethnl_req_info *req_base,
static int coalesce_reply_size(const struct ethnl_req_info *req_base,
const struct ethnl_reply_data *reply_base)
{
+ int modersz = nla_total_size(0) + /* _PROFILE_IRQ_MODERATION, nest */
+ nla_total_size(sizeof(u32)) + /* _IRQ_MODERATION_USEC */
+ nla_total_size(sizeof(u32)) + /* _IRQ_MODERATION_PKTS */
+ nla_total_size(sizeof(u32)); /* _IRQ_MODERATION_COMPS */
+
+ int total_modersz = nla_total_size(0) + /* _{R,T}X_PROFILE, nest */
+ modersz * NET_DIM_PARAMS_NUM_PROFILES;
+
return nla_total_size(sizeof(u32)) + /* _RX_USECS */
nla_total_size(sizeof(u32)) + /* _RX_MAX_FRAMES */
nla_total_size(sizeof(u32)) + /* _RX_USECS_IRQ */
@@ -108,7 +117,8 @@ static int coalesce_reply_size(const struct ethnl_req_info *req_base,
nla_total_size(sizeof(u8)) + /* _USE_CQE_MODE_RX */
nla_total_size(sizeof(u32)) + /* _TX_AGGR_MAX_BYTES */
nla_total_size(sizeof(u32)) + /* _TX_AGGR_MAX_FRAMES */
- nla_total_size(sizeof(u32)); /* _TX_AGGR_TIME_USECS */
+ nla_total_size(sizeof(u32)) + /* _TX_AGGR_TIME_USECS */
+ total_modersz * 2; /* _{R,T}X_PROFILE */
}
static bool coalesce_put_u32(struct sk_buff *skb, u16 attr_type, u32 val,
@@ -127,14 +137,84 @@ static bool coalesce_put_bool(struct sk_buff *skb, u16 attr_type, u32 val,
return nla_put_u8(skb, attr_type, !!val);
}
+/**
+ * coalesce_put_profile - fill reply with a nla nest with four child nla nests.
+ * @skb: socket buffer the message is stored in
+ * @attr_type: nest attr type ETHTOOL_A_COALESCE_*X_PROFILE
+ * @profile: data passed to userspace
+ * @coal_flags: modifiable parameters supported by the driver
+ *
+ * Put a dim profile nest attribute. Refer to ETHTOOL_A_PROFILE_IRQ_MODERATION.
+ *
+ * Return: 0 on success or a negative error code.
+ */
+static int coalesce_put_profile(struct sk_buff *skb, u16 attr_type,
+ const struct dim_cq_moder *profile,
+ u8 coal_flags)
+{
+ struct nlattr *profile_attr, *moder_attr;
+ int i, ret;
+
+ if (!profile || !coal_flags)
+ return 0;
+
+ profile_attr = nla_nest_start(skb, attr_type);
+ if (!profile_attr)
+ return -EMSGSIZE;
+
+ for (i = 0; i < NET_DIM_PARAMS_NUM_PROFILES; i++) {
+ moder_attr = nla_nest_start(skb,
+ ETHTOOL_A_PROFILE_IRQ_MODERATION);
+ if (!moder_attr) {
+ ret = -EMSGSIZE;
+ goto cancel_profile;
+ }
+
+ if (coal_flags & DIM_COALESCE_USEC) {
+ ret = nla_put_u32(skb, ETHTOOL_A_IRQ_MODERATION_USEC,
+ profile[i].usec);
+ if (ret)
+ goto cancel_moder;
+ }
+
+ if (coal_flags & DIM_COALESCE_PKTS) {
+ ret = nla_put_u32(skb, ETHTOOL_A_IRQ_MODERATION_PKTS,
+ profile[i].pkts);
+ if (ret)
+ goto cancel_moder;
+ }
+
+ if (coal_flags & DIM_COALESCE_COMPS) {
+ ret = nla_put_u32(skb, ETHTOOL_A_IRQ_MODERATION_COMPS,
+ profile[i].comps);
+ if (ret)
+ goto cancel_moder;
+ }
+
+ nla_nest_end(skb, moder_attr);
+ }
+
+ nla_nest_end(skb, profile_attr);
+
+ return 0;
+
+cancel_moder:
+ nla_nest_cancel(skb, moder_attr);
+cancel_profile:
+ nla_nest_cancel(skb, profile_attr);
+ return ret;
+}
+
static int coalesce_fill_reply(struct sk_buff *skb,
const struct ethnl_req_info *req_base,
const struct ethnl_reply_data *reply_base)
{
const struct coalesce_reply_data *data = COALESCE_REPDATA(reply_base);
const struct kernel_ethtool_coalesce *kcoal = &data->kernel_coalesce;
+ struct dim_irq_moder *moder = req_base->dev->irq_moder;
const struct ethtool_coalesce *coal = &data->coalesce;
u32 supported = data->supported_params;
+ int ret = 0;
if (coalesce_put_u32(skb, ETHTOOL_A_COALESCE_RX_USECS,
coal->rx_coalesce_usecs, supported) ||
@@ -192,11 +272,41 @@ static int coalesce_fill_reply(struct sk_buff *skb,
kcoal->tx_aggr_time_usecs, supported))
return -EMSGSIZE;
- return 0;
+ if (!moder)
+ return 0;
+
+ rcu_read_lock();
+ if (moder->profile_flags & DIM_PROFILE_RX) {
+ ret = coalesce_put_profile(skb, ETHTOOL_A_COALESCE_RX_PROFILE,
+ rcu_dereference(moder->rx_profile),
+ moder->coal_flags);
+ if (ret)
+ goto out;
+ }
+
+ if (moder->profile_flags & DIM_PROFILE_TX)
+ ret = coalesce_put_profile(skb, ETHTOOL_A_COALESCE_TX_PROFILE,
+ rcu_dereference(moder->tx_profile),
+ moder->coal_flags);
+
+out:
+ rcu_read_unlock();
+ return ret;
}
/* COALESCE_SET */
+static const struct nla_policy coalesce_irq_moderation_policy[] = {
+ [ETHTOOL_A_IRQ_MODERATION_USEC] = { .type = NLA_U32 },
+ [ETHTOOL_A_IRQ_MODERATION_PKTS] = { .type = NLA_U32 },
+ [ETHTOOL_A_IRQ_MODERATION_COMPS] = { .type = NLA_U32 },
+};
+
+static const struct nla_policy coalesce_profile_policy[] = {
+ [ETHTOOL_A_PROFILE_IRQ_MODERATION] =
+ NLA_POLICY_NESTED(coalesce_irq_moderation_policy),
+};
+
const struct nla_policy ethnl_coalesce_set_policy[] = {
[ETHTOOL_A_COALESCE_HEADER] =
NLA_POLICY_NESTED(ethnl_header_policy),
@@ -227,6 +337,10 @@ const struct nla_policy ethnl_coalesce_set_policy[] = {
[ETHTOOL_A_COALESCE_TX_AGGR_MAX_BYTES] = { .type = NLA_U32 },
[ETHTOOL_A_COALESCE_TX_AGGR_MAX_FRAMES] = { .type = NLA_U32 },
[ETHTOOL_A_COALESCE_TX_AGGR_TIME_USECS] = { .type = NLA_U32 },
+ [ETHTOOL_A_COALESCE_RX_PROFILE] =
+ NLA_POLICY_NESTED(coalesce_profile_policy),
+ [ETHTOOL_A_COALESCE_TX_PROFILE] =
+ NLA_POLICY_NESTED(coalesce_profile_policy),
};
static int
@@ -234,6 +348,7 @@ ethnl_set_coalesce_validate(struct ethnl_req_info *req_info,
struct genl_info *info)
{
const struct ethtool_ops *ops = req_info->dev->ethtool_ops;
+ struct dim_irq_moder *irq_moder = req_info->dev->irq_moder;
struct nlattr **tb = info->attrs;
u32 supported_params;
u16 a;
@@ -243,6 +358,12 @@ ethnl_set_coalesce_validate(struct ethnl_req_info *req_info,
/* make sure that only supported parameters are present */
supported_params = ops->supported_coalesce_params;
+ if (irq_moder && irq_moder->profile_flags & DIM_PROFILE_RX)
+ supported_params |= ETHTOOL_COALESCE_RX_PROFILE;
+
+ if (irq_moder && irq_moder->profile_flags & DIM_PROFILE_TX)
+ supported_params |= ETHTOOL_COALESCE_TX_PROFILE;
+
for (a = ETHTOOL_A_COALESCE_RX_USECS; a < __ETHTOOL_A_COALESCE_CNT; a++)
if (tb[a] && !(supported_params & attr_to_mask(a))) {
NL_SET_ERR_MSG_ATTR(info->extack, tb[a],
@@ -253,6 +374,128 @@ ethnl_set_coalesce_validate(struct ethnl_req_info *req_info,
return 1;
}
+/**
+ * ethnl_update_irq_moder - update a specific field in the given profile
+ * @irq_moder: place that collects dim related information
+ * @irq_field: field in profile to modify
+ * @attr_type: attr type ETHTOOL_A_IRQ_MODERATION_*
+ * @tb: netlink attribute with new values or null
+ * @coal_bit: DIM_COALESCE_* bit from coal_flags
+ * @extack: netlink extended ack
+ *
+ * Return: 0 on success or a negative error code.
+ */
+static int ethnl_update_irq_moder(struct dim_irq_moder *irq_moder,
+ u16 *irq_field, u16 attr_type,
+ struct nlattr **tb, u8 coal_bit,
+ struct netlink_ext_ack *extack)
+{
+ int ret = 0;
+
+ if (!tb[attr_type])
+ return 0;
+
+ if (irq_moder->coal_flags & coal_bit) {
+ *irq_field = nla_get_u32(tb[attr_type]);
+ } else {
+ NL_SET_BAD_ATTR(extack, tb[attr_type]);
+ ret = -EOPNOTSUPP;
+ }
+
+ return ret;
+}
+
+/**
+ * ethnl_update_profile - get a profile nest with child nests from userspace.
+ * @dev: netdevice to update the profile
+ * @dst: profile get from the driver and modified by ethnl_update_profile.
+ * @nests: nest attr ETHTOOL_A_COALESCE_*X_PROFILE to set profile.
+ * @extack: Netlink extended ack
+ *
+ * Layout of nests:
+ * Nested ETHTOOL_A_COALESCE_*X_PROFILE attr
+ * Nested ETHTOOL_A_PROFILE_IRQ_MODERATION attr
+ * ETHTOOL_A_IRQ_MODERATION_USEC attr
+ * ETHTOOL_A_IRQ_MODERATION_PKTS attr
+ * ETHTOOL_A_IRQ_MODERATION_COMPS attr
+ * ...
+ * Nested ETHTOOL_A_PROFILE_IRQ_MODERATION attr
+ * ETHTOOL_A_IRQ_MODERATION_USEC attr
+ * ETHTOOL_A_IRQ_MODERATION_PKTS attr
+ * ETHTOOL_A_IRQ_MODERATION_COMPS attr
+ *
+ * Return: 0 on success or a negative error code.
+ */
+static int ethnl_update_profile(struct net_device *dev,
+ struct dim_cq_moder __rcu **dst,
+ const struct nlattr *nests,
+ struct netlink_ext_ack *extack)
+{
+ int len_irq_moder = ARRAY_SIZE(coalesce_irq_moderation_policy);
+ struct nlattr *tb[ARRAY_SIZE(coalesce_irq_moderation_policy)];
+ struct dim_irq_moder *irq_moder = dev->irq_moder;
+ struct dim_cq_moder *new_profile, *old_profile;
+ int ret, rem, i = 0, len;
+ struct nlattr *nest;
+
+ if (!nests)
+ return 0;
+
+ if (!*dst)
+ return -EOPNOTSUPP;
+
+ old_profile = rtnl_dereference(*dst);
+ len = NET_DIM_PARAMS_NUM_PROFILES * sizeof(*old_profile);
+ new_profile = kmemdup(old_profile, len, GFP_KERNEL);
+ if (!new_profile)
+ return -ENOMEM;
+
+ nla_for_each_nested_type(nest, ETHTOOL_A_PROFILE_IRQ_MODERATION,
+ nests, rem) {
+ ret = nla_parse_nested(tb, len_irq_moder - 1, nest,
+ coalesce_irq_moderation_policy,
+ extack);
+ if (ret)
+ goto err_out;
+
+ ret = ethnl_update_irq_moder(irq_moder, &new_profile[i].usec,
+ ETHTOOL_A_IRQ_MODERATION_USEC,
+ tb, DIM_COALESCE_USEC,
+ extack);
+ if (ret)
+ goto err_out;
+
+ ret = ethnl_update_irq_moder(irq_moder, &new_profile[i].pkts,
+ ETHTOOL_A_IRQ_MODERATION_PKTS,
+ tb, DIM_COALESCE_PKTS,
+ extack);
+ if (ret)
+ goto err_out;
+
+ ret = ethnl_update_irq_moder(irq_moder, &new_profile[i].comps,
+ ETHTOOL_A_IRQ_MODERATION_COMPS,
+ tb, DIM_COALESCE_COMPS,
+ extack);
+ if (ret)
+ goto err_out;
+
+ i++;
+ }
+
+ /* After the profile is modified, dim itself is a dynamic
+ * mechanism and will quickly fit to the appropriate
+ * coalescing parameters according to the new profile.
+ */
+ rcu_assign_pointer(*dst, new_profile);
+ kfree_rcu(old_profile, rcu);
+
+ return 0;
+
+err_out:
+ kfree(new_profile);
+ return ret;
+}
+
static int
__ethnl_set_coalesce(struct ethnl_req_info *req_info, struct genl_info *info,
bool *dual_change)
@@ -317,6 +560,22 @@ __ethnl_set_coalesce(struct ethnl_req_info *req_info, struct genl_info *info,
ethnl_update_u32(&kernel_coalesce.tx_aggr_time_usecs,
tb[ETHTOOL_A_COALESCE_TX_AGGR_TIME_USECS], &mod);
+ if (dev->irq_moder && dev->irq_moder->profile_flags & DIM_PROFILE_RX) {
+ ret = ethnl_update_profile(dev, &dev->irq_moder->rx_profile,
+ tb[ETHTOOL_A_COALESCE_RX_PROFILE],
+ info->extack);
+ if (ret < 0)
+ return ret;
+ }
+
+ if (dev->irq_moder && dev->irq_moder->profile_flags & DIM_PROFILE_TX) {
+ ret = ethnl_update_profile(dev, &dev->irq_moder->tx_profile,
+ tb[ETHTOOL_A_COALESCE_TX_PROFILE],
+ info->extack);
+ if (ret < 0)
+ return ret;
+ }
+
/* Update operation modes */
ethnl_update_bool32(&coalesce.use_adaptive_rx_coalesce,
tb[ETHTOOL_A_COALESCE_USE_ADAPTIVE_RX], &mod_mode);
The NetDIM library, currently leveraged by an array of NICs, delivers excellent acceleration benefits. Nevertheless, NICs vary significantly in their dim profile list prerequisites. Specifically, virtio-net backends may present diverse sw or hw device implementation, making a one-size-fits-all parameter list impractical. On Alibaba Cloud, the virtio DPU's performance under the default DIM profile falls short of expectations, partly due to a mismatch in parameter configuration. I also noticed that ice/idpf/ena and other NICs have customized profilelist or placed some restrictions on dim capabilities. Motivated by this, I tried adding new params for "ethtool -C" that provides a per-device control to modify and access a device's interrupt parameters. Usage ======== The target NIC is named ethx. Assume that ethx only declares support for rx profile setting (with DIM_PROFILE_RX flag set in profile_flags) and supports modification of usec and pkt fields. 1. Query the currently customized list of the device $ ethtool -c ethx ... rx-profile: {.usec = 1, .pkts = 256, .comps = n/a,}, {.usec = 8, .pkts = 256, .comps = n/a,}, {.usec = 64, .pkts = 256, .comps = n/a,}, {.usec = 128, .pkts = 256, .comps = n/a,}, {.usec = 256, .pkts = 256, .comps = n/a,} tx-profile: n/a 2. Tune $ ethtool -C ethx rx-profile 1,1,n_2,n,n_3,3,n_4,4,n_n,5,n "n" means do not modify this field. $ ethtool -c ethx ... rx-profile: {.usec = 1, .pkts = 1, .comps = n/a,}, {.usec = 2, .pkts = 256, .comps = n/a,}, {.usec = 3, .pkts = 3, .comps = n/a,}, {.usec = 4, .pkts = 4, .comps = n/a,}, {.usec = 256, .pkts = 5, .comps = n/a,} tx-profile: n/a 3. Hint If the device does not support some type of customized dim profiles, the corresponding "n/a" will display. If the "n/a" field is being modified, -EOPNOTSUPP will be reported. Signed-off-by: Heng Qi <hengqi@linux.alibaba.com> --- Documentation/netlink/specs/ethtool.yaml | 31 +++ Documentation/networking/ethtool-netlink.rst | 4 + Documentation/networking/net_dim.rst | 42 +++ include/linux/dim.h | 58 ++++ include/linux/ethtool.h | 4 +- include/linux/netdevice.h | 3 + include/uapi/linux/ethtool_netlink.h | 22 ++ lib/dim/net_dim.c | 70 +++++ net/Kconfig | 1 + net/ethtool/coalesce.c | 263 ++++++++++++++++++- 10 files changed, 495 insertions(+), 3 deletions(-)