From: Kevin Kou Date: Fri, 27 Dec 2019 13:11:16 +0000 (+0000) Subject: sctp: add enabled check for path tracepoint loop. X-Git-Tag: v5.15~4637^2~185 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=f398efc14a9277b55defff71f59a46fdf13c713f;p=platform%2Fkernel%2Flinux-starfive.git sctp: add enabled check for path tracepoint loop. sctp_outq_sack is the main function handles SACK, it is called very frequently. As the commit "move trace_sctp_probe_path into sctp_outq_sack" added below code to this function, sctp tracepoint is disabled most of time, but the loop of transport list will be always called even though the tracepoint is disabled, this is unnecessary. + /* SCTP path tracepoint for congestion control debugging. */ + list_for_each_entry(transport, transport_list, transports) { + trace_sctp_probe_path(transport, asoc); + } This patch is to add tracepoint enabled check at outside of the loop of transport list, and avoid traversing the loop when trace is disabled, it is a small optimization. Signed-off-by: Kevin Kou Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller --- diff --git a/net/sctp/outqueue.c b/net/sctp/outqueue.c index 6b0b3ba..577e3bc4 100644 --- a/net/sctp/outqueue.c +++ b/net/sctp/outqueue.c @@ -1240,8 +1240,9 @@ int sctp_outq_sack(struct sctp_outq *q, struct sctp_chunk *chunk) transport_list = &asoc->peer.transport_addr_list; /* SCTP path tracepoint for congestion control debugging. */ - list_for_each_entry(transport, transport_list, transports) { - trace_sctp_probe_path(transport, asoc); + if (trace_sctp_probe_path_enabled()) { + list_for_each_entry(transport, transport_list, transports) + trace_sctp_probe_path(transport, asoc); } sack_ctsn = ntohl(sack->cum_tsn_ack);