From: wangweidong <wangweidong1@huawei.com>
Date: Wed, 12 Feb 2014 01:44:44 +0000 (+0800)
Subject: sctp: optimize the sctp_sysctl_net_register
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=efb842c45e667332774196bd5a1d539d048159cc;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

sctp: optimize the sctp_sysctl_net_register

Here, when the net is init_net, we needn't to kmemdup the ctl_table
again. So add a check for net. Also we can save some memory.

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/sctp/sysctl.c b/net/sctp/sysctl.c
index d354de5a6fe0..35c8923b5554 100644
--- a/net/sctp/sysctl.c
+++ b/net/sctp/sysctl.c
@@ -402,15 +402,18 @@ static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
 
 int sctp_sysctl_net_register(struct net *net)
 {
-	struct ctl_table *table;
-	int i;
+	struct ctl_table *table = sctp_net_table;
+
+	if (!net_eq(net, &init_net)) {
+		int i;
 
-	table = kmemdup(sctp_net_table, sizeof(sctp_net_table), GFP_KERNEL);
-	if (!table)
-		return -ENOMEM;
+		table = kmemdup(sctp_net_table, sizeof(sctp_net_table), GFP_KERNEL);
+		if (!table)
+			return -ENOMEM;
 
-	for (i = 0; table[i].data; i++)
-		table[i].data += (char *)(&net->sctp) - (char *)&init_net.sctp;
+		for (i = 0; table[i].data; i++)
+			table[i].data += (char *)(&net->sctp) - (char *)&init_net.sctp;
+	}
 
 	net->sctp.sysctl_header = register_net_sysctl(net, "net/sctp", table);
 	return 0;