[PATCH] [PATCH v5 net-next] net: openvswitch: Add support to count upcall packets

From: wangchuanlei
Date: Wed Nov 30 2022 - 02:25:48 EST


Add support to count upall packets, when kmod of openvswitch
upcall to userspace , here count the number of packets for
upcall succeed and failed, which is a better way to see how
many packets upcalled to userspace(ovs-vswitchd) on every
interfaces.

Here modify format of code used by comments of v4.

Changes since v4:
- optimize the function used by comments

Changes since v3:
- use nested NLA_NESTED attribute in netlink message

Changes since v2:
- add count of upcall failed packets

Changes since v1:
- add count of upcall succeed packets

Signed-off-by: wangchuanlei <wangchuanlei@xxxxxxxxxx>
---
include/uapi/linux/openvswitch.h | 19 ++++++++++++
net/openvswitch/datapath.c | 50 ++++++++++++++++++++++++++++++++
net/openvswitch/vport.c | 44 ++++++++++++++++++++++++++++
net/openvswitch/vport.h | 19 ++++++++++++
4 files changed, 132 insertions(+)

diff --git a/include/uapi/linux/openvswitch.h b/include/uapi/linux/openvswitch.h
index 94066f87e9ee..ad7cea9827cc 100644
--- a/include/uapi/linux/openvswitch.h
+++ b/include/uapi/linux/openvswitch.h
@@ -126,6 +126,11 @@ struct ovs_vport_stats {
__u64 tx_dropped; /* no space available in linux */
};

+struct ovs_vport_upcall_stats {
+ __u64 tx_success; /* total packets upcalls succeed */
+ __u64 tx_fail; /* total packets upcalls failed */
+};
+
/* Allow last Netlink attribute to be unaligned */
#define OVS_DP_F_UNALIGNED (1 << 0)

@@ -277,11 +282,25 @@ enum ovs_vport_attr {
OVS_VPORT_ATTR_PAD,
OVS_VPORT_ATTR_IFINDEX,
OVS_VPORT_ATTR_NETNSID,
+ OVS_VPORT_ATTR_UPCALL_STATS, /* struct ovs_vport_upcall_stats */
__OVS_VPORT_ATTR_MAX
};

#define OVS_VPORT_ATTR_MAX (__OVS_VPORT_ATTR_MAX - 1)

+/**
+ * enum ovs_vport_upcall_attr - attributes for %OVS_VPORT_UPCALL* commands
+ * @OVS_VPORT_UPCALL_SUCCESS: 64-bit upcall success packets.
+ * @OVS_VPORT_UPCALL_FAIL: 64-bit upcall fail packets.
+ */
+enum ovs_vport_upcall_attr {
+ OVS_VPORT_UPCALL_SUCCESS,
+ OVS_VPORT_UPCALL_FAIL,
+ __OVS_VPORT_UPCALL_MAX
+};
+
+#define OVS_VPORT_UPCALL_MAX (__OVS_VPORT_UPCALL_MAX - 1)
+
enum {
OVS_VXLAN_EXT_UNSPEC,
OVS_VXLAN_EXT_GBP, /* Flag or __u32 */
diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
index c8a9075ddd0a..f9279aee2adb 100644
--- a/net/openvswitch/datapath.c
+++ b/net/openvswitch/datapath.c
@@ -209,6 +209,26 @@ static struct vport *new_vport(const struct vport_parms *parms)
return vport;
}

+static void ovs_vport_upcalls(struct sk_buff *skb,
+ const struct dp_upcall_info *upcall_info,
+ bool upcall_result)
+{
+ struct vport *p = OVS_CB(skb)->input_vport;
+ struct vport_upcall_stats_percpu *vport_stats;
+
+ if (upcall_info->cmd != OVS_PACKET_CMD_MISS &&
+ upcall_info->cmd != OVS_PACKET_CMD_ACTION)
+ return;
+
+ vport_stats = this_cpu_ptr(p->upcall_stats);
+ u64_stats_update_begin(&vport_stats->syncp);
+ if (upcall_result)
+ u64_stats_inc(&vport_stats->n_success);
+ else
+ u64_stats_inc(&vport_stats->n_fail);
+ u64_stats_update_end(&vport_stats->syncp);
+}
+
void ovs_dp_detach_port(struct vport *p)
{
ASSERT_OVSL();
@@ -216,6 +236,9 @@ void ovs_dp_detach_port(struct vport *p)
/* First drop references to device. */
hlist_del_rcu(&p->dp_hash_node);

+ /* Free percpu memory */
+ free_percpu(p->upcall_stats);
+
/* Then destroy it. */
ovs_vport_del(p);
}
@@ -305,6 +328,8 @@ int ovs_dp_upcall(struct datapath *dp, struct sk_buff *skb,
err = queue_userspace_packet(dp, skb, key, upcall_info, cutlen);
else
err = queue_gso_packets(dp, skb, key, upcall_info, cutlen);
+
+ ovs_vport_upcalls(skb, upcall_info, !err);
if (err)
goto err;

@@ -1825,6 +1850,12 @@ static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
goto err_destroy_portids;
}

+ vport->upcall_stats = netdev_alloc_pcpu_stats(struct vport_upcall_stats_percpu);
+ if (!vport->upcall_stats) {
+ err = -ENOMEM;
+ goto err_destroy_portids;
+ }
+
err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
info->snd_seq, 0, OVS_DP_CMD_NEW);
BUG_ON(err < 0);
@@ -2068,6 +2099,8 @@ static int ovs_vport_cmd_fill_info(struct vport *vport, struct sk_buff *skb,
{
struct ovs_header *ovs_header;
struct ovs_vport_stats vport_stats;
+ struct ovs_vport_upcall_stats stat;
+ struct nlattr *nla;
int err;

ovs_header = genlmsg_put(skb, portid, seq, &dp_vport_genl_family,
@@ -2097,6 +2130,15 @@ static int ovs_vport_cmd_fill_info(struct vport *vport, struct sk_buff *skb,
OVS_VPORT_ATTR_PAD))
goto nla_put_failure;

+ nla = nla_nest_start_noflag(skb, OVS_VPORT_ATTR_UPCALL_STATS);
+ if (!nla)
+ goto nla_put_failure;
+
+ ovs_vport_get_upcall_stats(vport, &stat);
+ if (ovs_vport_put_upcall_stats(skb, &stat))
+ goto nla_put_failure;
+ nla_nest_end(skb, nla);
+
if (ovs_vport_get_upcall_portids(vport, skb))
goto nla_put_failure;

@@ -2278,6 +2320,13 @@ static int ovs_vport_cmd_new(struct sk_buff *skb, struct genl_info *info)
goto exit_unlock_free;
}

+ vport->upcall_stats = netdev_alloc_pcpu_stats(struct vport_upcall_stats_percpu);
+
+ if (!vport->upcall_stats) {
+ err = -ENOMEM;
+ goto exit_unlock_free;
+ }
+
err = ovs_vport_cmd_fill_info(vport, reply, genl_info_net(info),
info->snd_portid, info->snd_seq, 0,
OVS_VPORT_CMD_NEW, GFP_KERNEL);
@@ -2507,6 +2556,7 @@ static const struct nla_policy vport_policy[OVS_VPORT_ATTR_MAX + 1] = {
[OVS_VPORT_ATTR_OPTIONS] = { .type = NLA_NESTED },
[OVS_VPORT_ATTR_IFINDEX] = { .type = NLA_U32 },
[OVS_VPORT_ATTR_NETNSID] = { .type = NLA_S32 },
+ [OVS_VPORT_ATTR_UPCALL_STATS] = { .type = NLA_NESTED },
};

static const struct genl_small_ops dp_vport_genl_ops[] = {
diff --git a/net/openvswitch/vport.c b/net/openvswitch/vport.c
index 82a74f998966..fd95536b35ef 100644
--- a/net/openvswitch/vport.c
+++ b/net/openvswitch/vport.c
@@ -284,6 +284,50 @@ void ovs_vport_get_stats(struct vport *vport, struct ovs_vport_stats *stats)
stats->tx_packets = dev_stats->tx_packets;
}

+/**
+ * ovs_vport_get_upcall_stats - retrieve upcall stats
+ *
+ * @vport: vport from which to retrieve the stats
+ * @ovs_vport_upcall_stats: location to store stats
+ *
+ * Retrieves upcall stats for the given device.
+ *
+ * Must be called with ovs_mutex or rcu_read_lock.
+ */
+void ovs_vport_get_upcall_stats(struct vport *vport, struct ovs_vport_upcall_stats *stats)
+{
+ int i;
+
+ stats->tx_success = 0;
+ stats->tx_fail = 0;
+
+ for_each_possible_cpu(i) {
+ const struct vport_upcall_stats_percpu *upcall_stats;
+ unsigned int start;
+
+ upcall_stats = per_cpu_ptr(vport->upcall_stats, i);
+ do {
+ start = u64_stats_fetch_begin(&upcall_stats->syncp);
+ stats->tx_success += u64_stats_read(&upcall_stats->n_success);
+ stats->tx_fail += u64_stats_read(&upcall_stats->n_fail);
+ } while (u64_stats_fetch_retry(&upcall_stats->syncp, start));
+ }
+}
+
+int ovs_vport_put_upcall_stats(struct sk_buff *skb,
+ struct ovs_vport_upcall_stats *stats)
+{
+ if (nla_put_u64_64bit(skb, OVS_VPORT_UPCALL_SUCCESS, stats->tx_success,
+ OVS_VPORT_ATTR_PAD))
+ return -EMSGSIZE;
+
+ if (nla_put_u64_64bit(skb, OVS_VPORT_UPCALL_FAIL, stats->tx_fail,
+ OVS_VPORT_ATTR_PAD))
+ return -EMSGSIZE;
+
+ return 0;
+}
+
/**
* ovs_vport_get_options - retrieve device options
*
diff --git a/net/openvswitch/vport.h b/net/openvswitch/vport.h
index 7d276f60c000..b872117af763 100644
--- a/net/openvswitch/vport.h
+++ b/net/openvswitch/vport.h
@@ -32,6 +32,11 @@ struct vport *ovs_vport_locate(const struct net *net, const char *name);

void ovs_vport_get_stats(struct vport *, struct ovs_vport_stats *);

+void ovs_vport_get_upcall_stats(struct vport *vport,
+ struct ovs_vport_upcall_stats *stats);
+int ovs_vport_put_upcall_stats(struct sk_buff *skb,
+ struct ovs_vport_upcall_stats *stats);
+
int ovs_vport_set_options(struct vport *, struct nlattr *options);
int ovs_vport_get_options(const struct vport *, struct sk_buff *);

@@ -65,6 +70,7 @@ struct vport_portids {
* @hash_node: Element in @dev_table hash table in vport.c.
* @dp_hash_node: Element in @datapath->ports hash table in datapath.c.
* @ops: Class structure.
+ * @upcall_stats: Upcall stats of every ports.
* @detach_list: list used for detaching vport in net-exit call.
* @rcu: RCU callback head for deferred destruction.
*/
@@ -78,6 +84,7 @@ struct vport {
struct hlist_node hash_node;
struct hlist_node dp_hash_node;
const struct vport_ops *ops;
+ struct vport_upcall_stats_percpu __percpu *upcall_stats;

struct list_head detach_list;
struct rcu_head rcu;
@@ -137,6 +144,18 @@ struct vport_ops {
struct list_head list;
};

+/**
+ * struct vport_upcall_stats_percpu - per-cpu packet upcall statistics for
+ * a given vport.
+ * @n_success: Number of packets that upcall to userspace succeed.
+ * @n_fail: Number of packets that upcall to userspace failed.
+ */
+struct vport_upcall_stats_percpu {
+ struct u64_stats_sync syncp;
+ u64_stats_t n_success;
+ u64_stats_t n_fail;
+};
+
struct vport *ovs_vport_alloc(int priv_size, const struct vport_ops *,
const struct vport_parms *);
void ovs_vport_free(struct vport *);
--
2.27.0