diff mbox series

[RFC,net-next,v2,3/5] net: psample: add user cookie

Message ID 20240408125753.470419-4-amorenoz@redhat.com (mailing list archive)
State RFC
Delegated to: Netdev Maintainers
Headers show
Series net: openvswitch: Add sample multicasting. | expand

Checks

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netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 951 this patch: 951
netdev/build_tools success Errors and warnings before: 0 this patch: 0
netdev/cc_maintainers warning 3 maintainers not CCed: pabeni@redhat.com kuba@kernel.org edumazet@google.com
netdev/build_clang success Errors and warnings before: 954 this patch: 954
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 962 this patch: 962
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 39 lines checked
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netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Adrián Moreno April 8, 2024, 12:57 p.m. UTC
Add a user cookie to the sample metadata so that sample emitters can
provide more contextual information to samples.

If present, send the user cookie in a new attribute:
PSAMPLE_ATTR_USER_COOKIE.

Signed-off-by: Adrian Moreno <amorenoz@redhat.com>
---
 include/net/psample.h        |  2 ++
 include/uapi/linux/psample.h |  1 +
 net/psample/psample.c        | 12 +++++++++++-
 3 files changed, 14 insertions(+), 1 deletion(-)

Comments

Ilya Maximets April 8, 2024, 1:19 p.m. UTC | #1
[copying my previous reply since this version actually has netdev@ in Cc]

On 4/8/24 14:57, Adrian Moreno wrote:
> Add a user cookie to the sample metadata so that sample emitters can
> provide more contextual information to samples.
> 
> If present, send the user cookie in a new attribute:
> PSAMPLE_ATTR_USER_COOKIE.
> 
> Signed-off-by: Adrian Moreno <amorenoz@redhat.com>
> ---
>  include/net/psample.h        |  2 ++
>  include/uapi/linux/psample.h |  1 +
>  net/psample/psample.c        | 12 +++++++++++-
>  3 files changed, 14 insertions(+), 1 deletion(-)
> 
> diff --git a/include/net/psample.h b/include/net/psample.h
> index 0509d2d6be67..2503ab3c92a5 100644
> --- a/include/net/psample.h
> +++ b/include/net/psample.h
> @@ -25,6 +25,8 @@ struct psample_metadata {
>  	   out_tc_occ_valid:1,
>  	   latency_valid:1,
>  	   unused:5;
> +	u8 *user_cookie;

The code doesn't take ownership of this data.  It should probably
be a const pointer in this case.

This should also allow us to avoid a double copy first to the
psample_metadata and then to netlink skb, as users will know that
it is a const pointer and so they can hand the data directly.

> +	u32 user_cookie_len;
>  };
>  
>  struct psample_group *psample_group_get(struct net *net, u32 group_num);
> diff --git a/include/uapi/linux/psample.h b/include/uapi/linux/psample.h
> index 5e0305b1520d..1f61fd7ef7fd 100644
> --- a/include/uapi/linux/psample.h
> +++ b/include/uapi/linux/psample.h
> @@ -19,6 +19,7 @@ enum {
>  	PSAMPLE_ATTR_LATENCY,		/* u64, nanoseconds */
>  	PSAMPLE_ATTR_TIMESTAMP,		/* u64, nanoseconds */
>  	PSAMPLE_ATTR_PROTO,		/* u16 */
> +	PSAMPLE_ATTR_USER_COOKIE,

A comment would be nice.

>  
>  	__PSAMPLE_ATTR_MAX
>  };
> diff --git a/net/psample/psample.c b/net/psample/psample.c
> index a0cef63dfdec..9fdb88e01f21 100644
> --- a/net/psample/psample.c
> +++ b/net/psample/psample.c
> @@ -497,7 +497,8 @@ void psample_sample_packet(struct psample_group *group, struct sk_buff *skb,
>  		   nla_total_size(sizeof(u32)) +	/* group_num */
>  		   nla_total_size(sizeof(u32)) +	/* seq */
>  		   nla_total_size_64bit(sizeof(u64)) +	/* timestamp */
> -		   nla_total_size(sizeof(u16));		/* protocol */
> +		   nla_total_size(sizeof(u16)) +	/* protocol */
> +		   nla_total_size(md->user_cookie_len);	/* user_cookie */
>  
>  #ifdef CONFIG_INET
>  	tun_info = skb_tunnel_info(skb);
> @@ -596,6 +597,15 @@ void psample_sample_packet(struct psample_group *group, struct sk_buff *skb,
>  			goto error;
>  	}
>  #endif
> +	if (md->user_cookie && md->user_cookie_len) {
> +		int nla_len = nla_total_size(md->user_cookie_len);
> +		struct nlattr *nla;
> +
> +		nla = skb_put(nl_skb, nla_len);
> +		nla->nla_type = PSAMPLE_ATTR_USER_COOKIE;
> +		nla->nla_len = nla_attr_size(md->user_cookie_len);
> +		memcpy(nla_data(nla), md->user_cookie, md->user_cookie_len);
> +	}
>  
>  	genlmsg_end(nl_skb, data);
>  	psample_nl_obj_desc_init(&desc, group->group_num);
Adrián Moreno April 8, 2024, 7:28 p.m. UTC | #2
On 4/8/24 15:19, Ilya Maximets wrote:
> [copying my previous reply since this version actually has netdev@ in Cc]
> 
> On 4/8/24 14:57, Adrian Moreno wrote:
>> Add a user cookie to the sample metadata so that sample emitters can
>> provide more contextual information to samples.
>>
>> If present, send the user cookie in a new attribute:
>> PSAMPLE_ATTR_USER_COOKIE.
>>
>> Signed-off-by: Adrian Moreno <amorenoz@redhat.com>
>> ---
>>   include/net/psample.h        |  2 ++
>>   include/uapi/linux/psample.h |  1 +
>>   net/psample/psample.c        | 12 +++++++++++-
>>   3 files changed, 14 insertions(+), 1 deletion(-)
>>
>> diff --git a/include/net/psample.h b/include/net/psample.h
>> index 0509d2d6be67..2503ab3c92a5 100644
>> --- a/include/net/psample.h
>> +++ b/include/net/psample.h
>> @@ -25,6 +25,8 @@ struct psample_metadata {
>>   	   out_tc_occ_valid:1,
>>   	   latency_valid:1,
>>   	   unused:5;
>> +	u8 *user_cookie;
> 
> The code doesn't take ownership of this data.  It should probably
> be a const pointer in this case.
> 
> This should also allow us to avoid a double copy first to the
> psample_metadata and then to netlink skb, as users will know that
> it is a const pointer and so they can hand the data directly.
> 

Yep. You're right.


>> +	u32 user_cookie_len;
>>   };
>>   
>>   struct psample_group *psample_group_get(struct net *net, u32 group_num);
>> diff --git a/include/uapi/linux/psample.h b/include/uapi/linux/psample.h
>> index 5e0305b1520d..1f61fd7ef7fd 100644
>> --- a/include/uapi/linux/psample.h
>> +++ b/include/uapi/linux/psample.h
>> @@ -19,6 +19,7 @@ enum {
>>   	PSAMPLE_ATTR_LATENCY,		/* u64, nanoseconds */
>>   	PSAMPLE_ATTR_TIMESTAMP,		/* u64, nanoseconds */
>>   	PSAMPLE_ATTR_PROTO,		/* u16 */
>> +	PSAMPLE_ATTR_USER_COOKIE,
> 
> A comment would be nice.
> 

Definitely.

>>   
>>   	__PSAMPLE_ATTR_MAX
>>   };
>> diff --git a/net/psample/psample.c b/net/psample/psample.c
>> index a0cef63dfdec..9fdb88e01f21 100644
>> --- a/net/psample/psample.c
>> +++ b/net/psample/psample.c
>> @@ -497,7 +497,8 @@ void psample_sample_packet(struct psample_group *group, struct sk_buff *skb,
>>   		   nla_total_size(sizeof(u32)) +	/* group_num */
>>   		   nla_total_size(sizeof(u32)) +	/* seq */
>>   		   nla_total_size_64bit(sizeof(u64)) +	/* timestamp */
>> -		   nla_total_size(sizeof(u16));		/* protocol */
>> +		   nla_total_size(sizeof(u16)) +	/* protocol */
>> +		   nla_total_size(md->user_cookie_len);	/* user_cookie */
>>   
>>   #ifdef CONFIG_INET
>>   	tun_info = skb_tunnel_info(skb);
>> @@ -596,6 +597,15 @@ void psample_sample_packet(struct psample_group *group, struct sk_buff *skb,
>>   			goto error;
>>   	}
>>   #endif
>> +	if (md->user_cookie && md->user_cookie_len) {
>> +		int nla_len = nla_total_size(md->user_cookie_len);
>> +		struct nlattr *nla;
>> +
>> +		nla = skb_put(nl_skb, nla_len);
>> +		nla->nla_type = PSAMPLE_ATTR_USER_COOKIE;
>> +		nla->nla_len = nla_attr_size(md->user_cookie_len);
>> +		memcpy(nla_data(nla), md->user_cookie, md->user_cookie_len);
>> +	}
>>   
>>   	genlmsg_end(nl_skb, data);
>>   	psample_nl_obj_desc_init(&desc, group->group_num);
>
Ilya Maximets April 8, 2024, 8:28 p.m. UTC | #3
On 4/8/24 21:28, Adrian Moreno wrote:
> 
> 
> On 4/8/24 15:19, Ilya Maximets wrote:
>> [copying my previous reply since this version actually has netdev@ in Cc]
>>
>> On 4/8/24 14:57, Adrian Moreno wrote:
>>> Add a user cookie to the sample metadata so that sample emitters can
>>> provide more contextual information to samples.
>>>
>>> If present, send the user cookie in a new attribute:
>>> PSAMPLE_ATTR_USER_COOKIE.
>>>
>>> Signed-off-by: Adrian Moreno <amorenoz@redhat.com>
>>> ---
>>>   include/net/psample.h        |  2 ++
>>>   include/uapi/linux/psample.h |  1 +
>>>   net/psample/psample.c        | 12 +++++++++++-
>>>   3 files changed, 14 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/include/net/psample.h b/include/net/psample.h
>>> index 0509d2d6be67..2503ab3c92a5 100644
>>> --- a/include/net/psample.h
>>> +++ b/include/net/psample.h
>>> @@ -25,6 +25,8 @@ struct psample_metadata {
>>>   	   out_tc_occ_valid:1,
>>>   	   latency_valid:1,
>>>   	   unused:5;
>>> +	u8 *user_cookie;
>>
>> The code doesn't take ownership of this data.  It should probably
>> be a const pointer in this case.
>>
>> This should also allow us to avoid a double copy first to the
>> psample_metadata and then to netlink skb, as users will know that
>> it is a const pointer and so they can hand the data directly.
>>
> 
> Yep. You're right.
> 
> 
>>> +	u32 user_cookie_len;

BTW, u32 looks a little strange here and by extension in tc and OVS
as well.  We can't push move than 64K through netlink, AFAIK, so
u16 should be plenty here.  In practice, I hope, we'll not go over
u8 though.

Best regards, Ilya Maximets.
diff mbox series

Patch

diff --git a/include/net/psample.h b/include/net/psample.h
index 0509d2d6be67..2503ab3c92a5 100644
--- a/include/net/psample.h
+++ b/include/net/psample.h
@@ -25,6 +25,8 @@  struct psample_metadata {
 	   out_tc_occ_valid:1,
 	   latency_valid:1,
 	   unused:5;
+	u8 *user_cookie;
+	u32 user_cookie_len;
 };
 
 struct psample_group *psample_group_get(struct net *net, u32 group_num);
diff --git a/include/uapi/linux/psample.h b/include/uapi/linux/psample.h
index 5e0305b1520d..1f61fd7ef7fd 100644
--- a/include/uapi/linux/psample.h
+++ b/include/uapi/linux/psample.h
@@ -19,6 +19,7 @@  enum {
 	PSAMPLE_ATTR_LATENCY,		/* u64, nanoseconds */
 	PSAMPLE_ATTR_TIMESTAMP,		/* u64, nanoseconds */
 	PSAMPLE_ATTR_PROTO,		/* u16 */
+	PSAMPLE_ATTR_USER_COOKIE,
 
 	__PSAMPLE_ATTR_MAX
 };
diff --git a/net/psample/psample.c b/net/psample/psample.c
index a0cef63dfdec..9fdb88e01f21 100644
--- a/net/psample/psample.c
+++ b/net/psample/psample.c
@@ -497,7 +497,8 @@  void psample_sample_packet(struct psample_group *group, struct sk_buff *skb,
 		   nla_total_size(sizeof(u32)) +	/* group_num */
 		   nla_total_size(sizeof(u32)) +	/* seq */
 		   nla_total_size_64bit(sizeof(u64)) +	/* timestamp */
-		   nla_total_size(sizeof(u16));		/* protocol */
+		   nla_total_size(sizeof(u16)) +	/* protocol */
+		   nla_total_size(md->user_cookie_len);	/* user_cookie */
 
 #ifdef CONFIG_INET
 	tun_info = skb_tunnel_info(skb);
@@ -596,6 +597,15 @@  void psample_sample_packet(struct psample_group *group, struct sk_buff *skb,
 			goto error;
 	}
 #endif
+	if (md->user_cookie && md->user_cookie_len) {
+		int nla_len = nla_total_size(md->user_cookie_len);
+		struct nlattr *nla;
+
+		nla = skb_put(nl_skb, nla_len);
+		nla->nla_type = PSAMPLE_ATTR_USER_COOKIE;
+		nla->nla_len = nla_attr_size(md->user_cookie_len);
+		memcpy(nla_data(nla), md->user_cookie, md->user_cookie_len);
+	}
 
 	genlmsg_end(nl_skb, data);
 	psample_nl_obj_desc_init(&desc, group->group_num);