diff options
| -rw-r--r-- | include/uapi/linux/net_dropmon.h | 3 | ||||
| -rw-r--r-- | net/core/drop_monitor.c | 195 |
2 files changed, 196 insertions, 2 deletions
diff --git a/include/uapi/linux/net_dropmon.h b/include/uapi/linux/net_dropmon.h index 9f8fb1bb4aa4..3bddc9ec978c 100644 --- a/include/uapi/linux/net_dropmon.h +++ b/include/uapi/linux/net_dropmon.h @@ -87,6 +87,9 @@ enum net_dm_attr { NET_DM_ATTR_ORIGIN, /* u16 */ NET_DM_ATTR_HW_TRAP_GROUP_NAME, /* string */ NET_DM_ATTR_HW_TRAP_NAME, /* string */ + NET_DM_ATTR_HW_ENTRIES, /* nested */ + NET_DM_ATTR_HW_ENTRY, /* nested */ + NET_DM_ATTR_HW_TRAP_COUNT, /* u32 */ __NET_DM_ATTR_MAX, NET_DM_ATTR_MAX = __NET_DM_ATTR_MAX - 1 diff --git a/net/core/drop_monitor.c b/net/core/drop_monitor.c index 5a950b5af8fd..807c79d606aa 100644 --- a/net/core/drop_monitor.c +++ b/net/core/drop_monitor.c @@ -58,9 +58,26 @@ struct net_dm_stats { struct u64_stats_sync syncp; }; +#define NET_DM_MAX_HW_TRAP_NAME_LEN 40 + +struct net_dm_hw_entry { + char trap_name[NET_DM_MAX_HW_TRAP_NAME_LEN]; + u32 count; +}; + +struct net_dm_hw_entries { + u32 num_entries; + struct net_dm_hw_entry entries[0]; +}; + struct per_cpu_dm_data { - spinlock_t lock; /* Protects 'skb' and 'send_timer' */ - struct sk_buff *skb; + spinlock_t lock; /* Protects 'skb', 'hw_entries' and + * 'send_timer' + */ + union { + struct sk_buff *skb; + struct net_dm_hw_entries *hw_entries; + }; struct sk_buff_head drop_queue; struct work_struct dm_alert_work; struct timer_list send_timer; @@ -275,16 +292,189 @@ static void trace_napi_poll_hit(void *ignore, struct napi_struct *napi, rcu_read_unlock(); } +static struct net_dm_hw_entries * +net_dm_hw_reset_per_cpu_data(struct per_cpu_dm_data *hw_data) +{ + struct net_dm_hw_entries *hw_entries; + unsigned long flags; + + hw_entries = kzalloc(struct_size(hw_entries, entries, dm_hit_limit), + GFP_KERNEL); + if (!hw_entries) { + /* If the memory allocation failed, we try to perform another + * allocation in 1/10 second. Otherwise, the probe function + * will constantly bail out. + */ + mod_timer(&hw_data->send_timer, jiffies + HZ / 10); + } + + spin_lock_irqsave(&hw_data->lock, flags); + swap(hw_data->hw_entries, hw_entries); + spin_unlock_irqrestore(&hw_data->lock, flags); + + return hw_entries; +} + +static int net_dm_hw_entry_put(struct sk_buff *msg, + const struct net_dm_hw_entry *hw_entry) +{ + struct nlattr *attr; + + attr = nla_nest_start(msg, NET_DM_ATTR_HW_ENTRY); + if (!attr) + return -EMSGSIZE; + + if (nla_put_string(msg, NET_DM_ATTR_HW_TRAP_NAME, hw_entry->trap_name)) + goto nla_put_failure; + + if (nla_put_u32(msg, NET_DM_ATTR_HW_TRAP_COUNT, hw_entry->count)) + goto nla_put_failure; + + nla_nest_end(msg, attr); + + return 0; + +nla_put_failure: + nla_nest_cancel(msg, attr); + return -EMSGSIZE; +} + +static int net_dm_hw_entries_put(struct sk_buff *msg, + const struct net_dm_hw_entries *hw_entries) +{ + struct nlattr *attr; + int i; + + attr = nla_nest_start(msg, NET_DM_ATTR_HW_ENTRIES); + if (!attr) + return -EMSGSIZE; + + for (i = 0; i < hw_entries->num_entries; i++) { + int rc; + + rc = net_dm_hw_entry_put(msg, &hw_entries->entries[i]); + if (rc) + goto nla_put_failure; + } + + nla_nest_end(msg, attr); + + return 0; + +nla_put_failure: + nla_nest_cancel(msg, attr); + return -EMSGSIZE; +} + +static int +net_dm_hw_summary_report_fill(struct sk_buff *msg, + const struct net_dm_hw_entries *hw_entries) +{ + struct net_dm_alert_msg anc_hdr = { 0 }; + void *hdr; + int rc; + + hdr = genlmsg_put(msg, 0, 0, &net_drop_monitor_family, 0, + NET_DM_CMD_ALERT); + if (!hdr) + return -EMSGSIZE; + + /* We need to put the ancillary header in order not to break user + * space. + */ + if (nla_put(msg, NLA_UNSPEC, sizeof(anc_hdr), &anc_hdr)) + goto nla_put_failure; + + rc = net_dm_hw_entries_put(msg, hw_entries); + if (rc) + goto nla_put_failure; + + genlmsg_end(msg, hdr); + + return 0; + +nla_put_failure: + genlmsg_cancel(msg, hdr); + return -EMSGSIZE; +} + +static void net_dm_hw_summary_work(struct work_struct *work) +{ + struct net_dm_hw_entries *hw_entries; + struct per_cpu_dm_data *hw_data; + struct sk_buff *msg; + int rc; + + hw_data = container_of(work, struct per_cpu_dm_data, dm_alert_work); + + hw_entries = net_dm_hw_reset_per_cpu_data(hw_data); + if (!hw_entries) + return; + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) + goto out; + + rc = net_dm_hw_summary_report_fill(msg, hw_entries); + if (rc) { + nlmsg_free(msg); + goto out; + } + + genlmsg_multicast(&net_drop_monitor_family, msg, 0, 0, GFP_KERNEL); + +out: + kfree(hw_entries); +} + static void net_dm_hw_summary_probe(struct sk_buff *skb, const struct net_dm_hw_metadata *hw_metadata) { + struct net_dm_hw_entries *hw_entries; + struct net_dm_hw_entry *hw_entry; + struct per_cpu_dm_data *hw_data; + unsigned long flags; + int i; + + hw_data = this_cpu_ptr(&dm_hw_cpu_data); + spin_lock_irqsave(&hw_data->lock, flags); + hw_entries = hw_data->hw_entries; + + if (!hw_entries) + goto out; + + for (i = 0; i < hw_entries->num_entries; i++) { + hw_entry = &hw_entries->entries[i]; + if (!strncmp(hw_entry->trap_name, hw_metadata->trap_name, + NET_DM_MAX_HW_TRAP_NAME_LEN - 1)) { + hw_entry->count++; + goto out; + } + } + if (WARN_ON_ONCE(hw_entries->num_entries == dm_hit_limit)) + goto out; + + hw_entry = &hw_entries->entries[hw_entries->num_entries]; + strlcpy(hw_entry->trap_name, hw_metadata->trap_name, + NET_DM_MAX_HW_TRAP_NAME_LEN - 1); + hw_entry->count = 1; + hw_entries->num_entries++; + + if (!timer_pending(&hw_data->send_timer)) { + hw_data->send_timer.expires = jiffies + dm_delay * HZ; + add_timer(&hw_data->send_timer); + } + +out: + spin_unlock_irqrestore(&hw_data->lock, flags); } static const struct net_dm_alert_ops net_dm_alert_summary_ops = { .kfree_skb_probe = trace_kfree_skb_hit, .napi_poll_probe = trace_napi_poll_hit, .work_item_func = send_dm_alert, + .hw_work_item_func = net_dm_hw_summary_work, .hw_probe = net_dm_hw_summary_probe, }; @@ -1309,6 +1499,7 @@ static void net_dm_hw_cpu_data_fini(int cpu) struct per_cpu_dm_data *hw_data; hw_data = &per_cpu(dm_hw_cpu_data, cpu); + kfree(hw_data->hw_entries); __net_dm_cpu_data_fini(hw_data); } |