From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Ahern Subject: [PATCH iproute2-next 3/3] Improve batch times by caching link lookups Date: Mon, 7 Jan 2019 14:55:52 -0800 Message-ID: <20190107225552.8441-4-dsahern@kernel.org> References: <20190107225552.8441-1-dsahern@kernel.org> Cc: netdev@vger.kernel.org, David Ahern To: stephen@networkplumber.org Return-path: Received: from mail.kernel.org ([198.145.29.99]:38832 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726853AbfAGW4P (ORCPT ); Mon, 7 Jan 2019 17:56:15 -0500 In-Reply-To: <20190107225552.8441-1-dsahern@kernel.org> Sender: netdev-owner@vger.kernel.org List-ID: From: David Ahern ip route (for example) uses ll_name_to_index to convert the user given device name to an index. At the moment ll_name_to_index uses if_nametoindex which is ioctl based and does not cache the result. When using a batch file this means the same device lookups can be done repeatedly adding unnecessary overhead (socket + ioctl + close for each device lookup). Add a new function, ll_link_get, to send a netlink based RTM_GETLINK. If successful, cache the result in idx_head and name_head so future lookups can re-use the entry. Update ll_name_to_index to use ll_link_get over if_nametoindex. With this change the time to install 720,022 routes with 2 ecmp nexthops where the nexthop device is given is reduced from 30.7 seconds to 17.6 seconds. Signed-off-by: David Ahern --- lib/ll_map.c | 44 +++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 43 insertions(+), 1 deletion(-) diff --git a/lib/ll_map.c b/lib/ll_map.c index 8e8a0b1e9c9d..46c78df08c11 100644 --- a/lib/ll_map.c +++ b/lib/ll_map.c @@ -192,6 +192,46 @@ int ll_index_to_flags(unsigned idx) return im ? im->flags : -1; } +static int ll_link_get(const char *name) +{ + struct { + struct nlmsghdr n; + struct ifinfomsg ifm; + char buf[1024]; + } req = { + .n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)), + .n.nlmsg_flags = NLM_F_REQUEST, + .n.nlmsg_type = RTM_GETLINK, + }; + __u32 filt_mask = RTEXT_FILTER_VF | RTEXT_FILTER_SKIP_STATS; + struct rtnl_handle rth = {}; + struct nlmsghdr *answer; + int rc = 0; + + if (rtnl_open(&rth, 0) < 0) + return 0; + + addattr32(&req.n, sizeof(req), IFLA_EXT_MASK, filt_mask); + addattr_l(&req.n, sizeof(req), IFLA_IFNAME, name, + strlen(name) + 1); + + if (rtnl_talk(&rth, &req.n, &answer) < 0) + goto out; + + /* add entry to cache */ + rc = ll_remember_index(answer, NULL); + if (!rc) { + struct ifinfomsg *ifm = NLMSG_DATA(answer); + + rc = ifm->ifi_index; + } + + free(answer); +out: + rtnl_close(&rth); + return rc; +} + unsigned ll_name_to_index(const char *name) { const struct ll_cache *im; @@ -204,7 +244,9 @@ unsigned ll_name_to_index(const char *name) if (im) return im->index; - idx = if_nametoindex(name); + idx = ll_link_get(name); + if (idx == 0) + idx = if_nametoindex(name); if (idx == 0) idx = ll_idx_a2n(name); return idx; -- 2.11.0