From c35d86a23029f1186e3c7a65df7c38b762fb0434 Mon Sep 17 00:00:00 2001 From: Adrian Moreno Date: Thu, 4 Jul 2024 10:56:54 +0200 Subject: [PATCH] net: psample: skip packet copy if no listeners If nobody is listening on the multicast group, generating the sample, which involves copying packet data, seems completely unnecessary. Return fast in this case. Reviewed-by: Aaron Conole Acked-by: Eelco Chaudron Reviewed-by: Ido Schimmel Reviewed-by: Simon Horman Signed-off-by: Adrian Moreno Link: https://patch.msgid.link/20240704085710.353845-4-amorenoz@redhat.com Signed-off-by: Jakub Kicinski --- net/psample/psample.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/net/psample/psample.c b/net/psample/psample.c index b37488f426bc..1c76f3e48dcd 100644 --- a/net/psample/psample.c +++ b/net/psample/psample.c @@ -376,6 +376,10 @@ void psample_sample_packet(struct psample_group *group, struct sk_buff *skb, void *data; int ret; + if (!genl_has_listeners(&psample_nl_family, group->net, + PSAMPLE_NL_MCGRP_SAMPLE)) + return; + meta_len = (in_ifindex ? nla_total_size(sizeof(u16)) : 0) + (out_ifindex ? nla_total_size(sizeof(u16)) : 0) + (md->out_tc_valid ? nla_total_size(sizeof(u16)) : 0) + -- 2.50.1