From: Timo Teras Date: Tue, 27 Jan 2009 04:56:10 +0000 (-0800) Subject: gre: optimize hash lookup X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=afcf12422ec8236dc8b9238fef7a475876eea8da;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git gre: optimize hash lookup Instead of keeping candidate tunnel device from all categories, keep only one candidate with best score. This optimizes stack usage and speeds up exit code. Signed-off-by: Timo Teras Signed-off-by: David S. Miller --- diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index 4a43739c9035..07a188afb3ac 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -172,11 +172,11 @@ static struct ip_tunnel * ipgre_tunnel_lookup(struct net_device *dev, int link = dev->ifindex; unsigned h0 = HASH(remote); unsigned h1 = HASH(key); - struct ip_tunnel *t, *sel[4] = { NULL, NULL, NULL, NULL }; + struct ip_tunnel *t, *cand = NULL; struct ipgre_net *ign = net_generic(net, ipgre_net_id); int dev_type = (gre_proto == htons(ETH_P_TEB)) ? ARPHRD_ETHER : ARPHRD_IPGRE; - int idx; + int score, cand_score = 4; for (t = ign->tunnels_r_l[h0^h1]; t; t = t->next) { if (local != t->parms.iph.saddr || @@ -189,15 +189,18 @@ static struct ip_tunnel * ipgre_tunnel_lookup(struct net_device *dev, t->dev->type != dev_type) continue; - idx = 0; + score = 0; if (t->parms.link != link) - idx |= 1; + score |= 1; if (t->dev->type != dev_type) - idx |= 2; - if (idx == 0) + score |= 2; + if (score == 0) return t; - if (sel[idx] == NULL) - sel[idx] = t; + + if (score < cand_score) { + cand = t; + cand_score = score; + } } for (t = ign->tunnels_r[h0^h1]; t; t = t->next) { @@ -210,15 +213,18 @@ static struct ip_tunnel * ipgre_tunnel_lookup(struct net_device *dev, t->dev->type != dev_type) continue; - idx = 0; + score = 0; if (t->parms.link != link) - idx |= 1; + score |= 1; if (t->dev->type != dev_type) - idx |= 2; - if (idx == 0) + score |= 2; + if (score == 0) return t; - if (sel[idx] == NULL) - sel[idx] = t; + + if (score < cand_score) { + cand = t; + cand_score = score; + } } for (t = ign->tunnels_l[h1]; t; t = t->next) { @@ -233,15 +239,18 @@ static struct ip_tunnel * ipgre_tunnel_lookup(struct net_device *dev, t->dev->type != dev_type) continue; - idx = 0; + score = 0; if (t->parms.link != link) - idx |= 1; + score |= 1; if (t->dev->type != dev_type) - idx |= 2; - if (idx == 0) + score |= 2; + if (score == 0) return t; - if (sel[idx] == NULL) - sel[idx] = t; + + if (score < cand_score) { + cand = t; + cand_score = score; + } } for (t = ign->tunnels_wc[h1]; t; t = t->next) { @@ -253,20 +262,22 @@ static struct ip_tunnel * ipgre_tunnel_lookup(struct net_device *dev, t->dev->type != dev_type) continue; - idx = 0; + score = 0; if (t->parms.link != link) - idx |= 1; + score |= 1; if (t->dev->type != dev_type) - idx |= 2; - if (idx == 0) + score |= 2; + if (score == 0) return t; - if (sel[idx] == NULL) - sel[idx] = t; + + if (score < cand_score) { + cand = t; + cand_score = score; + } } - for (idx = 1; idx < ARRAY_SIZE(sel); idx++) - if (sel[idx] != NULL) - return sel[idx]; + if (cand != NULL) + return cand; if (ign->fb_tunnel_dev->flags & IFF_UP) return netdev_priv(ign->fb_tunnel_dev);