* [PATCH v2 net-next 1/2] vlan: use xarray iterator to implement /proc/net/vlan/config
2024-02-11 21:44 [PATCH v2 net-next 0/2] net: use net->dev_by_index in two places Eric Dumazet
@ 2024-02-11 21:44 ` Eric Dumazet
2024-02-12 16:09 ` Ido Schimmel
2024-02-11 21:44 ` [PATCH v2 net-next 2/2] rtnetlink: use xarray iterator to implement rtnl_dump_ifinfo() Eric Dumazet
2024-02-14 2:50 ` [PATCH v2 net-next 0/2] net: use net->dev_by_index in two places patchwork-bot+netdevbpf
2 siblings, 1 reply; 6+ messages in thread
From: Eric Dumazet @ 2024-02-11 21:44 UTC (permalink / raw)
To: David S . Miller, Jakub Kicinski, Paolo Abeni
Cc: Ido Schimmel, netdev, eric.dumazet, Eric Dumazet
Adopt net->dev_by_index as I did in commit 0e0939c0adf9
("net-procfs: use xarray iterator to implement /proc/net/dev")
Not only this removes quadratic behavior, it also makes sure
an existing vlan device is always visible in the dump,
regardless of concurrent net->dev_base_head changes.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
---
net/8021q/vlanproc.c | 46 +++++++++++++++-----------------------------
1 file changed, 16 insertions(+), 30 deletions(-)
diff --git a/net/8021q/vlanproc.c b/net/8021q/vlanproc.c
index 7825c129742a0f334bd8404bc3dc26547eb69083..87b959da00cd3844de1b56b45045e88e6a0293ba 100644
--- a/net/8021q/vlanproc.c
+++ b/net/8021q/vlanproc.c
@@ -163,48 +163,34 @@ void vlan_proc_rem_dev(struct net_device *vlandev)
* The following few functions build the content of /proc/net/vlan/config
*/
-/* start read of /proc/net/vlan/config */
-static void *vlan_seq_start(struct seq_file *seq, loff_t *pos)
- __acquires(rcu)
+static void *vlan_seq_from_index(struct seq_file *seq, loff_t *pos)
{
+ unsigned long ifindex = *pos;
struct net_device *dev;
- struct net *net = seq_file_net(seq);
- loff_t i = 1;
-
- rcu_read_lock();
- if (*pos == 0)
- return SEQ_START_TOKEN;
- for_each_netdev_rcu(net, dev) {
+ for_each_netdev_dump(seq_file_net(seq), dev, ifindex) {
if (!is_vlan_dev(dev))
continue;
-
- if (i++ == *pos)
- return dev;
+ *pos = dev->ifindex;
+ return dev;
}
+ return NULL;
+}
+
+static void *vlan_seq_start(struct seq_file *seq, loff_t *pos)
+ __acquires(rcu)
+{
+ rcu_read_lock();
+ if (*pos == 0)
+ return SEQ_START_TOKEN;
- return NULL;
+ return vlan_seq_from_index(seq, pos);
}
static void *vlan_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
- struct net_device *dev;
- struct net *net = seq_file_net(seq);
-
++*pos;
-
- dev = v;
- if (v == SEQ_START_TOKEN)
- dev = net_device_entry(&net->dev_base_head);
-
- for_each_netdev_continue_rcu(net, dev) {
- if (!is_vlan_dev(dev))
- continue;
-
- return dev;
- }
-
- return NULL;
+ return vlan_seq_from_index(seq, pos);
}
static void vlan_seq_stop(struct seq_file *seq, void *v)
--
2.43.0.687.g38aa6559b0-goog
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v2 net-next 2/2] rtnetlink: use xarray iterator to implement rtnl_dump_ifinfo()
2024-02-11 21:44 [PATCH v2 net-next 0/2] net: use net->dev_by_index in two places Eric Dumazet
2024-02-11 21:44 ` [PATCH v2 net-next 1/2] vlan: use xarray iterator to implement /proc/net/vlan/config Eric Dumazet
@ 2024-02-11 21:44 ` Eric Dumazet
2024-02-12 16:10 ` Ido Schimmel
2024-02-14 2:50 ` [PATCH v2 net-next 0/2] net: use net->dev_by_index in two places patchwork-bot+netdevbpf
2 siblings, 1 reply; 6+ messages in thread
From: Eric Dumazet @ 2024-02-11 21:44 UTC (permalink / raw)
To: David S . Miller, Jakub Kicinski, Paolo Abeni
Cc: Ido Schimmel, netdev, eric.dumazet, Eric Dumazet
Adopt net->dev_by_index as I did in commit 0e0939c0adf9
("net-procfs: use xarray iterator to implement /proc/net/dev")
This makes sure an existing device is always visible in the dump,
regardless of concurrent insertions/deletions.
v2: added suggestions from Jakub Kicinski and Ido Schimmel,
thanks for the help !
Link: https://lore.kernel.org/all/20240209142441.6c56435b@kernel.org/
Link: https://lore.kernel.org/all/ZckR-XOsULLI9EHc@shredder/
Signed-off-by: Eric Dumazet <edumazet@google.com>
---
net/core/rtnetlink.c | 58 +++++++++++++++-----------------------------
1 file changed, 20 insertions(+), 38 deletions(-)
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 31f433950c8dc953bcb65cc0469f7df962314b87..6f1c5537e8421bdb677e926e7fc9be1beb5ff969 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -2188,25 +2188,22 @@ static int rtnl_valid_dump_ifinfo_req(const struct nlmsghdr *nlh,
static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
{
+ const struct rtnl_link_ops *kind_ops = NULL;
struct netlink_ext_ack *extack = cb->extack;
const struct nlmsghdr *nlh = cb->nlh;
struct net *net = sock_net(skb->sk);
- struct net *tgt_net = net;
- int h, s_h;
- int idx = 0, s_idx;
- struct net_device *dev;
- struct hlist_head *head;
+ unsigned int flags = NLM_F_MULTI;
struct nlattr *tb[IFLA_MAX+1];
+ struct {
+ unsigned long ifindex;
+ } *ctx = (void *)cb->ctx;
+ struct net *tgt_net = net;
u32 ext_filter_mask = 0;
- const struct rtnl_link_ops *kind_ops = NULL;
- unsigned int flags = NLM_F_MULTI;
+ struct net_device *dev;
int master_idx = 0;
int netnsid = -1;
int err, i;
- s_h = cb->args[0];
- s_idx = cb->args[1];
-
err = rtnl_valid_dump_ifinfo_req(nlh, cb->strict_check, tb, extack);
if (err < 0) {
if (cb->strict_check)
@@ -2250,36 +2247,21 @@ static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
flags |= NLM_F_DUMP_FILTERED;
walk_entries:
- for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
- idx = 0;
- head = &tgt_net->dev_index_head[h];
- hlist_for_each_entry(dev, head, index_hlist) {
- if (link_dump_filtered(dev, master_idx, kind_ops))
- goto cont;
- if (idx < s_idx)
- goto cont;
- err = rtnl_fill_ifinfo(skb, dev, net,
- RTM_NEWLINK,
- NETLINK_CB(cb->skb).portid,
- nlh->nlmsg_seq, 0, flags,
- ext_filter_mask, 0, NULL, 0,
- netnsid, GFP_KERNEL);
-
- if (err < 0) {
- if (likely(skb->len))
- goto out;
-
- goto out_err;
- }
-cont:
- idx++;
+ err = 0;
+ for_each_netdev_dump(tgt_net, dev, ctx->ifindex) {
+ if (link_dump_filtered(dev, master_idx, kind_ops))
+ continue;
+ err = rtnl_fill_ifinfo(skb, dev, net, RTM_NEWLINK,
+ NETLINK_CB(cb->skb).portid,
+ nlh->nlmsg_seq, 0, flags,
+ ext_filter_mask, 0, NULL, 0,
+ netnsid, GFP_KERNEL);
+ if (err < 0) {
+ if (likely(skb->len))
+ err = skb->len;
+ break;
}
}
-out:
- err = skb->len;
-out_err:
- cb->args[1] = idx;
- cb->args[0] = h;
cb->seq = tgt_net->dev_base_seq;
nl_dump_check_consistent(cb, nlmsg_hdr(skb));
if (netnsid >= 0)
--
2.43.0.687.g38aa6559b0-goog
^ permalink raw reply related [flat|nested] 6+ messages in thread