Re: [ovs-dev] [PATCH] [PATCH 1/2] openvswitch: Add support to count upall packets
From: wangchuanlei <hidden>
Date: 2022-09-19 11:26:36
Also in:
lkml
Thank you for review, your comments is useful and i'll resubmit a patch based on your comments. Best reagards! wangchuanlei On 14 Sep 2022, at 14:14, wangchuanlei wrote:
Add support to count upcall packets on every interface. I always encounter high cpu use of ovs-vswictchd, this help to check which interface send too many packets without open vlog/set switch, and have no influence on datapath.
Hi, I did not do a full review, but I think we should not try to make the same mistake as before and embed a structure inside a netlink message. You are adding âstruct ovs_vport_upcall_statsâ but in theory, you could have just added the new entry to âovs_vport_statsâ. But this is breaking userspace as it expects an exact structure size :( So I think the right approach would be to have âOVS_VPORT_ATTR_UPCALL_STATSâ be an NLA_NESTED type, and have individual stat attributes as NLA_U64 (or whatever type you need). What is also confusing is that you use upcall_packets in ovs_vport_upcall_stats, which to me are the total of up calls, but you called it n_missed in your stats. I think you should try to avoid missed in the upcall path, and just call it n_upcall_packets also. In addition, I think you should keep two types of statics, and make them available, namely the total number of upcalls and the total of upcall failures. Cheers, Eelco
quoted hunk
Signed-off-by: wangchuanlei <redacted> --- include/uapi/linux/openvswitch.h | 5 ++++ net/openvswitch/datapath.c | 45 ++++++++++++++++++++++++++++++++ net/openvswitch/datapath.h | 10 +++++++ net/openvswitch/vport.c | 31 ++++++++++++++++++++++ net/openvswitch/vport.h | 4 +++ 5 files changed, 95 insertions(+)diff --git a/include/uapi/linux/openvswitch.hb/include/uapi/linux/openvswitch.h index 94066f87e9ee..8ec45511bc41 100644--- a/include/uapi/linux/openvswitch.h +++ b/include/uapi/linux/openvswitch.h@@ -126,6 +126,10 @@ struct ovs_vport_stats { __u64 tx_dropped; /* no space available in linux */ }; +struct ovs_vport_upcall_stats { + __u64 upcall_packets; /* total packets upcalls */ +}; + /* Allow last Netlink attribute to be unaligned */ #define OVS_DP_F_UNALIGNED (1 << 0)@@ -277,6 +281,7 @@ 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 };diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c index c8a9075ddd0a..f4e1f67dc57a 100644 --- a/net/openvswitch/datapath.c +++ b/net/openvswitch/datapath.c@@ -209,6 +209,23 @@ 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) { + if (upcall_info->cmd == OVS_PACKET_CMD_MISS || + upcall_info->cmd == OVS_PACKET_CMD_ACTION) { + const struct vport *p = OVS_CB(skb)->input_vport; + struct vport_upcall_stats_percpu *vport_stats; + u64 *stats_counter_upcall; + + vport_stats = this_cpu_ptr(p->vport_upcall_stats_percpu); + stats_counter_upcall = &vport_stats->n_missed; + u64_stats_update_begin(&vport_stats->syncp); + (*stats_counter_upcall)++; + u64_stats_update_end(&vport_stats->syncp); + } +} + void ovs_dp_detach_port(struct vport *p) { ASSERT_OVSL();@@ -216,6 +233,9 @@ 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->vport_upcall_stats_percpu); + /* Then destroy it. */ ovs_vport_del(p); }@@ -308,6 +328,8 @@ int ovs_dp_upcall(struct datapath *dp, struct sk_buff *skb, if (err) goto err; + ovs_vport_upcalls(skb, upcall_info); + return 0; err:@@ -1825,6 +1847,13 @@ static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info) goto err_destroy_portids; } + vport->vport_upcall_stats_percpu = + netdev_alloc_pcpu_stats(struct vport_upcall_stats_percpu); + if (!vport->vport_upcall_stats_percpu) { + 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 +2097,7 @@ 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 vport_upcall_stats; int err; ovs_header = genlmsg_put(skb, portid, seq, &dp_vport_genl_family, @@ -2097,6 +2127,13 @@ static int ovs_vport_cmd_fill_info(struct vport *vport, struct sk_buff *skb, OVS_VPORT_ATTR_PAD)) goto nla_put_failure; + ovs_vport_get_upcall_stats(vport, &vport_upcall_stats); + if (nla_put_64bit(skb, OVS_VPORT_ATTR_UPCALL_STATS, + sizeof(struct ovs_vport_upcall_stats), + &vport_upcall_stats, + OVS_VPORT_ATTR_PAD)) + goto nla_put_failure; + if (ovs_vport_get_upcall_portids(vport, skb)) goto nla_put_failure;@@ -2278,6 +2315,14 @@ static int ovs_vport_cmd_new(struct sk_buff *skb, struct genl_info *info) goto exit_unlock_free; } + vport->vport_upcall_stats_percpu = + netdev_alloc_pcpu_stats(struct vport_upcall_stats_percpu); + + if (!vport->vport_upcall_stats_percpu) { + 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); diff --gita/net/openvswitch/datapath.h b/net/openvswitch/datapath.h index 0cd29971a907..57fc002142a3 100644--- a/net/openvswitch/datapath.h +++ b/net/openvswitch/datapath.h@@ -50,6 +50,16 @@ struct dp_stats_percpu { struct u64_stats_sync syncp; }; +/** + * struct vport_upcall_stats_percpu - per-cpu packet upcall +statistics for + * a given vport. + * @n_missed: Number of packets that upcall to userspace. + */ +struct vport_upcall_stats_percpu { + u64 n_missed; + struct u64_stats_sync syncp; +}; + /** * struct dp_nlsk_pids - array of netlink portids of for a datapath. * This is used when OVS_DP_F_DISPATCH_UPCALL_PER_CPUdiff --git a/net/openvswitch/vport.c b/net/openvswitch/vport.c index82a74f998966..c05056f907f0 100644--- a/net/openvswitch/vport.c +++ b/net/openvswitch/vport.c@@ -284,6 +284,37 @@ 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->upcall_packets = 0; + + for_each_possible_cpu(i) { + const struct vport_upcall_stats_percpu *percpu_upcall_stats; + struct vport_upcall_stats_percpu local_stats; + unsigned int start; + + percpu_upcall_stats = per_cpu_ptr(vport->vport_upcall_stats_percpu, i); + do { + start = u64_stats_fetch_begin_irq(&percpu_upcall_stats->syncp); + local_stats = *percpu_upcall_stats; + } while (u64_stats_fetch_retry_irq(&percpu_upcall_stats->syncp, +start)); + + stats->upcall_packets += local_stats.n_missed; + } +} + /** * ovs_vport_get_options - retrieve device options *diff --git a/net/openvswitch/vport.h b/net/openvswitch/vport.h index7d276f60c000..6defacd6d718 100644--- a/net/openvswitch/vport.h +++ b/net/openvswitch/vport.h@@ -32,6 +32,9 @@ 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_set_options(struct vport *, struct nlattr *options); int ovs_vport_get_options(const struct vport *, struct sk_buff *);@@ -78,6 +81,7 @@ struct vport { struct hlist_node hash_node; struct hlist_node dp_hash_node; const struct vport_ops *ops; + struct vport_upcall_stats_percpu __percpu +*vport_upcall_stats_percpu; struct list_head detach_list; struct rcu_head rcu; --2.27.0 _______________________________________________ dev mailing list dev@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev