diff options
authorPhil Sutter <>2020-05-13 16:29:51 +0200
committerPhil Sutter <>2020-05-14 12:27:24 +0200
commitc96c7da272e33a34770c4de4e3e50f7ed264672e (patch)
parentf3a61c8760d40cd2ac5822f5d724a97041cfdd63 (diff)
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 <>
1 files changed, 6 insertions, 3 deletions
diff --git a/src/parser_json.c b/src/parser_json.c
index 4468407b..3a84bd96 100644
--- a/src/parser_json.c
+++ b/src/parser_json.c
@@ -3847,12 +3847,15 @@ static uint64_t handle_from_nlmsg(const struct nlmsghdr *nlh)
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");