[RFC net-next v4 6/9] netdev-genl: Support setting per-NAPI config values

Joe Damato posted 9 patches 1 month, 3 weeks ago
There is a newer version of this series
[RFC net-next v4 6/9] netdev-genl: Support setting per-NAPI config values
Posted by Joe Damato 1 month, 3 weeks ago
Add support to set per-NAPI defer_hard_irqs and gro_flush_timeout.

Signed-off-by: Joe Damato <jdamato@fastly.com>
---
 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 bf13613eaa0d..7f8d2489c68c 100644
--- a/Documentation/netlink/specs/netdev.yaml
+++ b/Documentation/netlink/specs/netdev.yaml
@@ -690,6 +690,17 @@ operations:
         reply:
           attributes:
             - id
+    -
+      name: napi-set
+      doc: Set configurable NAPI instance settings.
+      attribute-set: napi
+      flags: [ admin-perm ]
+      do:
+        request:
+          attributes:
+            - napi-id
+            - defer-hard-irqs
+            - gro-flush-timeout
 
 kernel-family:
   headers: [ "linux/list.h"]
diff --git a/include/uapi/linux/netdev.h b/include/uapi/linux/netdev.h
index cacd33359c76..e3ebb49f60d2 100644
--- a/include/uapi/linux/netdev.h
+++ b/include/uapi/linux/netdev.h
@@ -201,6 +201,7 @@ enum {
 	NETDEV_CMD_NAPI_GET,
 	NETDEV_CMD_QSTATS_GET,
 	NETDEV_CMD_BIND_RX,
+	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 b28424ae06d5..901c6f65b735 100644
--- a/net/core/netdev-genl-gen.c
+++ b/net/core/netdev-genl-gen.c
@@ -87,6 +87,13 @@ static const struct nla_policy netdev_bind_rx_nl_policy[NETDEV_A_DMABUF_FD + 1]
 	[NETDEV_A_DMABUF_QUEUES] = NLA_POLICY_NESTED(netdev_queue_id_nl_policy),
 };
 
+/* 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_UINT },
+};
+
 /* Ops table for netdev */
 static const struct genl_split_ops netdev_nl_ops[] = {
 	{
@@ -171,6 +178,13 @@ static const struct genl_split_ops netdev_nl_ops[] = {
 		.maxattr	= NETDEV_A_DMABUF_FD,
 		.flags		= GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
 	},
+	{
+		.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 8cda334fd042..85e6d7c95ada 100644
--- a/net/core/netdev-genl-gen.h
+++ b/net/core/netdev-genl-gen.h
@@ -30,6 +30,7 @@ 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);
 int netdev_nl_bind_rx_doit(struct sk_buff *skb, struct genl_info *info);
diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c
index 64e5e4cee60d..59523318d620 100644
--- a/net/core/netdev-genl.c
+++ b/net/core/netdev-genl.c
@@ -303,6 +303,51 @@ 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;
+	u32 defer = 0;
+
+	if (info->attrs[NETDEV_A_NAPI_DEFER_HARD_IRQS]) {
+		defer = nla_get_u32(info->attrs[NETDEV_A_NAPI_DEFER_HARD_IRQS]);
+		napi_set_defer_hard_irqs(napi, defer);
+	}
+
+	if (info->attrs[NETDEV_A_NAPI_GRO_FLUSH_TIMEOUT]) {
+		gro_flush_timeout = nla_get_uint(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;
+	unsigned int 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 {
+		NL_SET_BAD_ATTR(info->extack, info->attrs[NETDEV_A_NAPI_ID]);
+		err = -ENOENT;
+	}
+
+	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 cacd33359c76..e3ebb49f60d2 100644
--- a/tools/include/uapi/linux/netdev.h
+++ b/tools/include/uapi/linux/netdev.h
@@ -201,6 +201,7 @@ enum {
 	NETDEV_CMD_NAPI_GET,
 	NETDEV_CMD_QSTATS_GET,
 	NETDEV_CMD_BIND_RX,
+	NETDEV_CMD_NAPI_SET,
 
 	__NETDEV_CMD_MAX,
 	NETDEV_CMD_MAX = (__NETDEV_CMD_MAX - 1)
-- 
2.25.1
Re: [RFC net-next v4 6/9] netdev-genl: Support setting per-NAPI config values
Posted by Joe Damato 1 month, 2 weeks ago
On Tue, Oct 01, 2024 at 11:52:37PM +0000, Joe Damato wrote:
> Add support to set per-NAPI defer_hard_irqs and gro_flush_timeout.
> 
> Signed-off-by: Joe Damato <jdamato@fastly.com>
> ---
>  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/net/core/netdev-genl-gen.c b/net/core/netdev-genl-gen.c
> index b28424ae06d5..901c6f65b735 100644
> --- a/net/core/netdev-genl-gen.c
> +++ b/net/core/netdev-genl-gen.c
> @@ -87,6 +87,13 @@ static const struct nla_policy netdev_bind_rx_nl_policy[NETDEV_A_DMABUF_FD + 1]
>  	[NETDEV_A_DMABUF_QUEUES] = NLA_POLICY_NESTED(netdev_queue_id_nl_policy),
>  };
>  
> +/* 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 },

Noticed this while re-reading the code; planning on changing this
from NLA_S32 to NLA_U32 for v5.
Re: [RFC net-next v4 6/9] netdev-genl: Support setting per-NAPI config values
Posted by Jakub Kicinski 1 month, 2 weeks ago
On Tue, 8 Oct 2024 11:20:47 -0700 Joe Damato wrote:
> Noticed this while re-reading the code; planning on changing this
> from NLA_S32 to NLA_U32 for v5.

Make sure you edit the spec, not the output. Looks like there may be 
a problem here (napi-id vs id in the attributes).

Make sure you run: ./tools/net/ynl/ynl-regen.sh -f
and the tree is clean afterwards
Re: [RFC net-next v4 6/9] netdev-genl: Support setting per-NAPI config values
Posted by Joe Damato 1 month, 2 weeks ago
On Tue, Oct 08, 2024 at 03:19:34PM -0700, Jakub Kicinski wrote:
> On Tue, 8 Oct 2024 11:20:47 -0700 Joe Damato wrote:
> > Noticed this while re-reading the code; planning on changing this
> > from NLA_S32 to NLA_U32 for v5.
> 
> Make sure you edit the spec, not the output. Looks like there may be 
> a problem here (napi-id vs id in the attributes).

I'm not sure I follow this part, sorry if I'm just missing something
here.

I was referring to NETDEV_A_NAPI_DEFER_HARD_IRQS which in RFCv4 is
listed as NLA_S32 (in this patch):

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 },

However, in the yaml spec (patch 2/9):

+      -
+        name: defer-hard-irqs
+        doc: The number of consecutive empty polls before IRQ deferral ends
+             and hardware IRQs are re-enabled.
+        type: u32
+        checks:
+          max: s32-max

So the type is u32 but with a "checks" to match what happens now in
sysfs.

That's why I mentioned changing NLA_S32 to NLA_U32.

Am I missing something? Not sure what you meant by "napi-id vs id" ?

> Make sure you run: ./tools/net/ynl/ynl-regen.sh -f
> and the tree is clean afterwards

OK, will do.
Re: [RFC net-next v4 6/9] netdev-genl: Support setting per-NAPI config values
Posted by Jakub Kicinski 1 month, 2 weeks ago
On Tue, 8 Oct 2024 16:00:41 -0700 Joe Damato wrote:
> > Make sure you edit the spec, not the output. Looks like there may be 
> > a problem here (napi-id vs id in the attributes).  
> 
> I'm not sure I follow this part, sorry if I'm just missing something
> here.
> 
> I was referring to NETDEV_A_NAPI_DEFER_HARD_IRQS which in RFCv4 is
> listed as NLA_S32 (in this patch):
> 
> 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 },
> 
> However, in the yaml spec (patch 2/9):
> 
> +      -
> +        name: defer-hard-irqs
> +        doc: The number of consecutive empty polls before IRQ deferral ends
> +             and hardware IRQs are re-enabled.
> +        type: u32
> +        checks:
> +          max: s32-max
> 
> So the type is u32 but with a "checks" to match what happens now in
> sysfs.
> 
> That's why I mentioned changing NLA_S32 to NLA_U32.
> 
> Am I missing something?

YNL will generate the correct code for your - the right type
and the right range validation. Run the command below to see.

> Not sure what you meant by "napi-id vs id" ?

I can't apply the series now, but when it was posted the YNL code
generation failed here complaining about napi-id not existing in
the attribute set in which it is used. In the napi attribute set
the NAPI ID is called just "id", not "napi-id".

> > Make sure you run: ./tools/net/ynl/ynl-regen.sh -f
> > and the tree is clean afterwards  
> 
> OK, will do.
Re: [RFC net-next v4 6/9] netdev-genl: Support setting per-NAPI config values
Posted by Joe Damato 1 month, 2 weeks ago
On Tue, Oct 08, 2024 at 04:19:19PM -0700, Jakub Kicinski wrote:
> On Tue, 8 Oct 2024 16:00:41 -0700 Joe Damato wrote:
> > > Make sure you edit the spec, not the output. Looks like there may be 
> > > a problem here (napi-id vs id in the attributes).  
> > 
> > I'm not sure I follow this part, sorry if I'm just missing something
> > here.
> > 
> > I was referring to NETDEV_A_NAPI_DEFER_HARD_IRQS which in RFCv4 is
> > listed as NLA_S32 (in this patch):
> > 
> > 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 },
> > 
> > However, in the yaml spec (patch 2/9):
> > 
> > +      -
> > +        name: defer-hard-irqs
> > +        doc: The number of consecutive empty polls before IRQ deferral ends
> > +             and hardware IRQs are re-enabled.
> > +        type: u32
> > +        checks:
> > +          max: s32-max
> > 
> > So the type is u32 but with a "checks" to match what happens now in
> > sysfs.
> > 
> > That's why I mentioned changing NLA_S32 to NLA_U32.
> > 
> > Am I missing something?
> 
> YNL will generate the correct code for your - the right type
> and the right range validation. Run the command below to see.
> 
> > Not sure what you meant by "napi-id vs id" ?
> 
> I can't apply the series now, but when it was posted the YNL code
> generation failed here complaining about napi-id not existing in
> the attribute set in which it is used. In the napi attribute set
> the NAPI ID is called just "id", not "napi-id".

Ah, I see what you mean now. It should have been obvious, but the
-gen* files are, uh, auto-generated ;)

And yes, I see now that the attribute set names it "id", so I've
fixed it and the command runs clean and I'll include the generated
output this time in the v5.