From c96c7da272e33a34770c4de4e3e50f7ed264672e Mon Sep 17 00:00:00 2001 From: Phil Sutter Date: Wed, 13 May 2020 16:29:51 +0200 Subject: JSON: Improve performance of json_events_cb() The function tries to insert handles into JSON input for echo option. Yet there may be nothing to do if the given netlink message doesn't contain a handle, e.g. if it is an 'add element' command. Calling seqnum_to_json() is pointless overhead in that case, and if input is large this overhead is significant. Better wait with that call until after checking if the message is relevant at all. Signed-off-by: Phil Sutter Acked-by: Eric Garver --- src/parser_json.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) Index: nftables-0.9.3/src/parser_json.c =================================================================== --- nftables-0.9.3.orig/src/parser_json.c +++ nftables-0.9.3/src/parser_json.c @@ -3838,12 +3838,15 @@ static uint64_t handle_from_nlmsg(const } int json_events_cb(const struct nlmsghdr *nlh, struct netlink_mon_handler *monh) { - json_t *tmp, *json = seqnum_to_json(nlh->nlmsg_seq); uint64_t handle = handle_from_nlmsg(nlh); + json_t *tmp, *json; void *iter; - /* might be anonymous set, ignore message */ - if (!json || !handle) + if (!handle) + return MNL_CB_OK; + + json = seqnum_to_json(nlh->nlmsg_seq); + if (!json) return MNL_CB_OK; tmp = json_object_get(json, "add");