net: psample: add user cookie

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.

Reviewed-by: Michal Kubiak <michal.kubiak@intel.com>
Acked-by: Eelco Chaudron <echaudro@redhat.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Adrian Moreno <amorenoz@redhat.com>
Link: https://patch.msgid.link/20240704085710.353845-2-amorenoz@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/include/net/psample.h b/include/net/psample.h
index 0509d2d6be676638e35cae3c6b4325524d693c25..2ac71260a546117e5f8807857065907ec26cf661 100644 (file)
--- 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;
+       const 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 e585db5bf2d2f2fde1ae77e918a50471b00fedcd..e80637e1d97b95579bb4175f98be49fcb8d12496 100644 (file)
--- 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,       /* binary, user provided data */
 
        __PSAMPLE_ATTR_MAX
 };

diff --git a/net/psample/psample.c b/net/psample/psample.c
index a5d9b8446f77f28c1e32525b2e7eb5fd52eddcb4..b37488f426bc2ff9eb8e4aed548e8431436dbed9 100644 (file)
--- a/net/psample/psample.c
+++ b/net/psample/psample.c
@@ -386,7 +386,9 @@ 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 */
+                  (md->user_cookie_len ?
+                   nla_total_size(md->user_cookie_len) : 0); /* user cookie */
 
 #ifdef CONFIG_INET
        tun_info = skb_tunnel_info(skb);
@@ -486,6 +488,11 @@ void psample_sample_packet(struct psample_group *group, struct sk_buff *skb,
        }
 #endif
 
+       if (md->user_cookie && md->user_cookie_len &&
+           nla_put(nl_skb, PSAMPLE_ATTR_USER_COOKIE, md->user_cookie_len,
+                   md->user_cookie))
+               goto error;
+
        genlmsg_end(nl_skb, data);
        genlmsg_multicast_netns(&psample_nl_family, group->net, nl_skb, 0,
                                PSAMPLE_NL_MCGRP_SAMPLE, GFP_ATOMIC);