nagai/kernel
3
0
Fork 0
forked from mirrors/linux
Code Pull requests Activity

netlink: Use rhashtable walk interface in diag dump

Browse source 
This patch converts the diag dumping code to use the rhashtable
walk code instead of going through rhashtable by hand.  The lock
nl_table_lock is now only taken while we process the multicast
list as it's not needed for the rhashtable walk.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Herbert Xu 2016-08-19 16:21:37 +08:00 committed by David S. Miller
parent 39ec406d12
commit ad20207432
1 changed files with 73 additions and 30 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

103
net/netlink/diag.c
View file

@ -63,43 +63,75 @@ static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
static int __netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
int protocol, int s_num)
{
struct rhashtable_iter *hti = (void *)cb->args[2];
struct netlink_table *tbl = &nl_table[protocol];
struct rhashtable *ht = &tbl->hash;
const struct bucket_table *htbl = rht_dereference_rcu(ht->tbl, ht);
struct net *net = sock_net(skb->sk);
struct netlink_diag_req *req;
struct netlink_sock *nlsk;
struct sock *sk;
int ret = 0, num = 0, i;
int num = 2;
int ret = 0;
req = nlmsg_data(cb->nlh);
for (i = 0; i < htbl->size; i++) {
struct rhash_head *pos;
if (s_num > 1)
goto mc_list;
rht_for_each_entry_rcu(nlsk, pos, htbl, i, node) {
sk = (struct sock *)nlsk;
num--;
if (!net_eq(sock_net(sk), net))
continue;
if (num < s_num) {
num++;
if (!hti) {
hti = kmalloc(sizeof(*hti), GFP_KERNEL);
if (!hti)
return -ENOMEM;
cb->args[2] = (long)hti;
}
if (!s_num)
rhashtable_walk_enter(&tbl->hash, hti);
ret = rhashtable_walk_start(hti);
if (ret == -EAGAIN)
ret = 0;
if (ret)
goto stop;
while ((nlsk = rhashtable_walk_next(hti))) {
if (IS_ERR(nlsk)) {
ret = PTR_ERR(nlsk);
if (ret == -EAGAIN) {
ret = 0;
continue;
}
break;
}
if (sk_diag_fill(sk, skb, req,
NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq,
NLM_F_MULTI,
sock_i_ino(sk)) < 0) {
ret = 1;
goto done;
}
sk = (struct sock *)nlsk;
num++;
if (!net_eq(sock_net(sk), net))
continue;
if (sk_diag_fill(sk, skb, req,
NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq,
NLM_F_MULTI,
sock_i_ino(sk)) < 0) {
ret = 1;
break;
}
}
stop:
rhashtable_walk_stop(hti);
if (ret)
goto done;
rhashtable_walk_exit(hti);
cb->args[2] = 0;
num++;
mc_list:
read_lock(&nl_table_lock);
sk_for_each_bound(sk, &tbl->mc_list) {
if (sk_hashed(sk))
continue;
@ -116,13 +148,14 @@ static int __netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
NLM_F_MULTI,
sock_i_ino(sk)) < 0) {
ret = 1;
goto done;
break;
}
num++;
}
read_unlock(&nl_table_lock);
done:
cb->args[0] = num;
cb->args[1] = protocol;
return ret;
}
@ -131,20 +164,20 @@ static int netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
{
struct netlink_diag_req *req;
int s_num = cb->args[0];
int err = 0;
req = nlmsg_data(cb->nlh);
rcu_read_lock();
read_lock(&nl_table_lock);
if (req->sdiag_protocol == NDIAG_PROTO_ALL) {
int i;
for (i = cb->args[1]; i < MAX_LINKS; i++) {
if (__netlink_diag_dump(skb, cb, i, s_num))
err = __netlink_diag_dump(skb, cb, i, s_num);
if (err)
break;
s_num = 0;
}
cb->args[1] = i;
} else {
if (req->sdiag_protocol >= MAX_LINKS) {
read_unlock(&nl_table_lock);
@ -152,13 +185,22 @@ static int netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
return -ENOENT;
}
__netlink_diag_dump(skb, cb, req->sdiag_protocol, s_num);
err = __netlink_diag_dump(skb, cb, req->sdiag_protocol, s_num);
}
read_unlock(&nl_table_lock);
rcu_read_unlock();
return err < 0 ? err : skb->len;
}
return skb->len;
static int netlink_diag_dump_done(struct netlink_callback *cb)
{
struct rhashtable_iter *hti = (void *)cb->args[2];
if (cb->args[0] == 1)
rhashtable_walk_exit(hti);
kfree(hti);
return 0;
}
static int netlink_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
@ -172,6 +214,7 @@ static int netlink_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
if (h->nlmsg_flags & NLM_F_DUMP) {
struct netlink_dump_control c = {
.dump = netlink_diag_dump,
.done = netlink_diag_dump_done,
};
return netlink_dump_start(net->diag_nlsk, skb, h, &c);
} else