[PATCH net-next 5/5] netdev-genl: Support setting per-NAPI config values

Joe Damato
2024-08-29T13:13:21Z

Add support to set per-NAPI defer_hard_irqs and gro_flush_timeout.

Signed-off-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: Martin Karsten <mkarsten@uwaterloo.ca>
Tested-by: Martin Karsten <mkarsten@uwaterloo.ca>
---
Documentation/netlink/specs/netdev.yaml | 11 ++++++
include/uapi/linux/netdev.h | 1 +
net/core/netdev-genl-gen.c | 14 ++++++++
net/core/netdev-genl-gen.h | 1 +
net/core/netdev-genl.c | 45 +++++++++++++++++++++++++
tools/include/uapi/linux/netdev.h | 1 +
6 files changed, 73 insertions(+)

diff --git a/Documentation/netlink/specs/netdev.yaml b/Documentation/netlink/specs/netdev.yaml
index 290894962ac4..cb7049a1d6d8 100644
--- a/Documentation/netlink/specs/netdev.yaml
+++ b/Documentation/netlink/specs/netdev.yaml
@@ -631,6 +631,17 @@ operations:
- rx-bytes
- tx-packets
- tx-bytes
+ -
+ name: napi-set
+ doc: Set configurable NAPI instance settings.
+ attribute-set: napi
+ flags: [ admin-perm ]
+ do:
+ request:
+ attributes:
+ - id
+ - defer-hard-irqs
+ - gro-flush-timeout

mcast-groups:
list:
diff --git a/include/uapi/linux/netdev.h b/include/uapi/linux/netdev.h
index b088a34e9254..4c5bfbc85504 100644
--- a/include/uapi/linux/netdev.h
+++ b/include/uapi/linux/netdev.h
@@ -188,6 +188,7 @@ enum {
NETDEV_CMD_QUEUE_GET,
NETDEV_CMD_NAPI_GET,
NETDEV_CMD_QSTATS_GET,
+ NETDEV_CMD_NAPI_SET,

__NETDEV_CMD_MAX,
NETDEV_CMD_MAX = (__NETDEV_CMD_MAX - 1)
diff --git a/net/core/netdev-genl-gen.c b/net/core/netdev-genl-gen.c
index 8350a0afa9ec..5ddb5d926850 100644
--- a/net/core/netdev-genl-gen.c
+++ b/net/core/netdev-genl-gen.c
@@ -74,6 +74,13 @@ static const struct nla_policy netdev_qstats_get_nl_policy[NETDEV_A_QSTATS_SCOPE
[NETDEV_A_QSTATS_SCOPE] = NLA_POLICY_MASK(NLA_UINT, 0x1),
};

+/* NETDEV_CMD_NAPI_SET - set */
+static const struct nla_policy netdev_napi_set_nl_policy[NETDEV_A_NAPI_GRO_FLUSH_TIMEOUT + 1] = {
+ [NETDEV_A_NAPI_ID] = { .type = NLA_U32, },
+ [NETDEV_A_NAPI_DEFER_HARD_IRQS] = { .type = NLA_S32 },
+ [NETDEV_A_NAPI_GRO_FLUSH_TIMEOUT] = { .type = NLA_U64 },
+};
+
/* Ops table for netdev */
static const struct genl_split_ops netdev_nl_ops[] = {
{
@@ -151,6 +158,13 @@ static const struct genl_split_ops netdev_nl_ops[] = {
.maxattr = NETDEV_A_QSTATS_SCOPE,
.flags = GENL_CMD_CAP_DUMP,
},
+ {
+ .cmd = NETDEV_CMD_NAPI_SET,
+ .doit = netdev_nl_napi_set_doit,
+ .policy = netdev_napi_set_nl_policy,
+ .maxattr = NETDEV_A_NAPI_GRO_FLUSH_TIMEOUT,
+ .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
+ },
};

static const struct genl_multicast_group netdev_nl_mcgrps[] = {
diff --git a/net/core/netdev-genl-gen.h b/net/core/netdev-genl-gen.h
index 4db40fd5b4a9..b70cb0f20acb 100644
--- a/net/core/netdev-genl-gen.h
+++ b/net/core/netdev-genl-gen.h
@@ -28,6 +28,7 @@ int netdev_nl_queue_get_dumpit(struct sk_buff *skb,
struct netlink_callback *cb);
int netdev_nl_napi_get_doit(struct sk_buff *skb, struct genl_info *info);
int netdev_nl_napi_get_dumpit(struct sk_buff *skb, struct netlink_callback *cb);
+int netdev_nl_napi_set_doit(struct sk_buff *skb, struct genl_info *info);
int netdev_nl_qstats_get_dumpit(struct sk_buff *skb,
struct netlink_callback *cb);

diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c
index 2eee95d05fe0..43dd30eadbc6 100644
--- a/net/core/netdev-genl.c
+++ b/net/core/netdev-genl.c
@@ -299,6 +299,51 @@ int netdev_nl_napi_get_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
return err;
}

+static int
+netdev_nl_napi_set_config(struct napi_struct *napi, struct genl_info *info)
+{
+ u64 gro_flush_timeout = 0;
+ int defer = 0;
+
+ if (info->attrs[NETDEV_A_NAPI_DEFER_HARD_IRQS]) {
+ defer = nla_get_s32(info->attrs[NETDEV_A_NAPI_DEFER_HARD_IRQS]);
+ if (defer < 0)
+ return -EINVAL;
+ napi_set_defer_hard_irqs(napi, defer);
+ }
+
+ if (info->attrs[NETDEV_A_NAPI_GRO_FLUSH_TIMEOUT]) {
+ gro_flush_timeout = nla_get_u64(info->attrs[NETDEV_A_NAPI_GRO_FLUSH_TIMEOUT]);
+ napi_set_gro_flush_timeout(napi, gro_flush_timeout);
+ }
+
+ return 0;
+}
+
+int netdev_nl_napi_set_doit(struct sk_buff *skb, struct genl_info *info)
+{
+ struct napi_struct *napi;
+ u32 napi_id;
+ int err;
+
+ if (GENL_REQ_ATTR_CHECK(info, NETDEV_A_NAPI_ID))
+ return -EINVAL;
+
+ napi_id = nla_get_u32(info->attrs[NETDEV_A_NAPI_ID]);
+
+ rtnl_lock();
+
+ napi = napi_by_id(napi_id);
+ if (napi)
+ err = netdev_nl_napi_set_config(napi, info);
+ else
+ err = -EINVAL;
+
+ rtnl_unlock();
+
+ return err;
+}
+
static int
netdev_nl_queue_fill_one(struct sk_buff *rsp, struct net_device *netdev,
u32 q_idx, u32 q_type, const struct genl_info *info)
diff --git a/tools/include/uapi/linux/netdev.h b/tools/include/uapi/linux/netdev.h
index b088a34e9254..4c5bfbc85504 100644
--- a/tools/include/uapi/linux/netdev.h
+++ b/tools/include/uapi/linux/netdev.h
@@ -188,6 +188,7 @@ enum {
NETDEV_CMD_QUEUE_GET,
NETDEV_CMD_NAPI_GET,
NETDEV_CMD_QSTATS_GET,
+ NETDEV_CMD_NAPI_SET,

__NETDEV_CMD_MAX,
NETDEV_CMD_MAX = (__NETDEV_CMD_MAX - 1)
--
2.25.1