Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Monitoring code for network dropped packet alerts |
| 3 | * |
| 4 | * Copyright (C) 2009 Neil Horman <nhorman@tuxdriver.com> |
| 5 | */ |
| 6 | |
| 7 | #include <linux/netdevice.h> |
| 8 | #include <linux/etherdevice.h> |
| 9 | #include <linux/string.h> |
| 10 | #include <linux/if_arp.h> |
| 11 | #include <linux/inetdevice.h> |
| 12 | #include <linux/inet.h> |
| 13 | #include <linux/interrupt.h> |
| 14 | #include <linux/netpoll.h> |
| 15 | #include <linux/sched.h> |
| 16 | #include <linux/delay.h> |
| 17 | #include <linux/types.h> |
| 18 | #include <linux/workqueue.h> |
| 19 | #include <linux/netlink.h> |
| 20 | #include <linux/net_dropmon.h> |
| 21 | #include <linux/percpu.h> |
| 22 | #include <linux/timer.h> |
| 23 | #include <linux/bitops.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 24 | #include <linux/slab.h> |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 25 | #include <net/genetlink.h> |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 26 | #include <net/netevent.h> |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 27 | |
Steven Rostedt | ad8d75f | 2009-04-14 19:39:12 -0400 | [diff] [blame] | 28 | #include <trace/events/skb.h> |
David S. Miller | 9cbc1cb | 2009-06-15 03:02:23 -0700 | [diff] [blame] | 29 | #include <trace/events/napi.h> |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 30 | |
| 31 | #include <asm/unaligned.h> |
| 32 | |
| 33 | #define TRACE_ON 1 |
| 34 | #define TRACE_OFF 0 |
| 35 | |
| 36 | static void send_dm_alert(struct work_struct *unused); |
| 37 | |
| 38 | |
| 39 | /* |
| 40 | * Globals, our netlink socket pointer |
| 41 | * and the work handle that will send up |
| 42 | * netlink alerts |
| 43 | */ |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 44 | static int trace_state = TRACE_OFF; |
Neil Horman | cde2e9a | 2012-04-27 10:11:48 +0000 | [diff] [blame] | 45 | static DEFINE_MUTEX(trace_state_mutex); |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 46 | |
| 47 | struct per_cpu_dm_data { |
| 48 | struct work_struct dm_alert_work; |
Neil Horman | 3885ca7 | 2012-04-27 10:11:49 +0000 | [diff] [blame] | 49 | struct sk_buff __rcu *skb; |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 50 | atomic_t dm_hit_count; |
| 51 | struct timer_list send_timer; |
Neil Horman | 4fdcfa1 | 2012-05-01 08:18:02 +0000 | [diff] [blame^] | 52 | int cpu; |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 53 | }; |
| 54 | |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 55 | struct dm_hw_stat_delta { |
| 56 | struct net_device *dev; |
Neil Horman | 5848cc0 | 2009-09-02 14:37:45 -0700 | [diff] [blame] | 57 | unsigned long last_rx; |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 58 | struct list_head list; |
| 59 | struct rcu_head rcu; |
| 60 | unsigned long last_drop_val; |
| 61 | }; |
| 62 | |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 63 | static struct genl_family net_drop_monitor_family = { |
| 64 | .id = GENL_ID_GENERATE, |
| 65 | .hdrsize = 0, |
| 66 | .name = "NET_DM", |
Neil Horman | 683703a | 2009-04-27 03:17:31 -0700 | [diff] [blame] | 67 | .version = 2, |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 68 | .maxattr = NET_DM_CMD_MAX, |
| 69 | }; |
| 70 | |
| 71 | static DEFINE_PER_CPU(struct per_cpu_dm_data, dm_cpu_data); |
| 72 | |
| 73 | static int dm_hit_limit = 64; |
| 74 | static int dm_delay = 1; |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 75 | static unsigned long dm_hw_check_delta = 2*HZ; |
| 76 | static LIST_HEAD(hw_stats_list); |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 77 | |
| 78 | static void reset_per_cpu_data(struct per_cpu_dm_data *data) |
| 79 | { |
| 80 | size_t al; |
| 81 | struct net_dm_alert_msg *msg; |
Neil Horman | 683703a | 2009-04-27 03:17:31 -0700 | [diff] [blame] | 82 | struct nlattr *nla; |
Neil Horman | 3885ca7 | 2012-04-27 10:11:49 +0000 | [diff] [blame] | 83 | struct sk_buff *skb; |
| 84 | struct sk_buff *oskb = rcu_dereference_protected(data->skb, 1); |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 85 | |
| 86 | al = sizeof(struct net_dm_alert_msg); |
| 87 | al += dm_hit_limit * sizeof(struct net_dm_drop_point); |
Neil Horman | 683703a | 2009-04-27 03:17:31 -0700 | [diff] [blame] | 88 | al += sizeof(struct nlattr); |
| 89 | |
Neil Horman | 3885ca7 | 2012-04-27 10:11:49 +0000 | [diff] [blame] | 90 | skb = genlmsg_new(al, GFP_KERNEL); |
| 91 | |
| 92 | if (skb) { |
| 93 | genlmsg_put(skb, 0, 0, &net_drop_monitor_family, |
| 94 | 0, NET_DM_CMD_ALERT); |
| 95 | nla = nla_reserve(skb, NLA_UNSPEC, |
| 96 | sizeof(struct net_dm_alert_msg)); |
| 97 | msg = nla_data(nla); |
| 98 | memset(msg, 0, al); |
Neil Horman | 4fdcfa1 | 2012-05-01 08:18:02 +0000 | [diff] [blame^] | 99 | } else |
| 100 | schedule_work_on(data->cpu, &data->dm_alert_work); |
Neil Horman | 3885ca7 | 2012-04-27 10:11:49 +0000 | [diff] [blame] | 101 | |
| 102 | /* |
| 103 | * Don't need to lock this, since we are guaranteed to only |
| 104 | * run this on a single cpu at a time. |
| 105 | * Note also that we only update data->skb if the old and new skb |
| 106 | * pointers don't match. This ensures that we don't continually call |
| 107 | * synchornize_rcu if we repeatedly fail to alloc a new netlink message. |
| 108 | */ |
| 109 | if (skb != oskb) { |
| 110 | rcu_assign_pointer(data->skb, skb); |
| 111 | |
| 112 | synchronize_rcu(); |
| 113 | |
| 114 | atomic_set(&data->dm_hit_count, dm_hit_limit); |
| 115 | } |
| 116 | |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 117 | } |
| 118 | |
| 119 | static void send_dm_alert(struct work_struct *unused) |
| 120 | { |
| 121 | struct sk_buff *skb; |
Neil Horman | 3885ca7 | 2012-04-27 10:11:49 +0000 | [diff] [blame] | 122 | struct per_cpu_dm_data *data = &get_cpu_var(dm_cpu_data); |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 123 | |
Neil Horman | 4fdcfa1 | 2012-05-01 08:18:02 +0000 | [diff] [blame^] | 124 | WARN_ON_ONCE(data->cpu != smp_processor_id()); |
| 125 | |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 126 | /* |
| 127 | * Grab the skb we're about to send |
| 128 | */ |
Neil Horman | 3885ca7 | 2012-04-27 10:11:49 +0000 | [diff] [blame] | 129 | skb = rcu_dereference_protected(data->skb, 1); |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 130 | |
| 131 | /* |
| 132 | * Replace it with a new one |
| 133 | */ |
| 134 | reset_per_cpu_data(data); |
| 135 | |
| 136 | /* |
| 137 | * Ship it! |
| 138 | */ |
Neil Horman | 3885ca7 | 2012-04-27 10:11:49 +0000 | [diff] [blame] | 139 | if (skb) |
| 140 | genlmsg_multicast(skb, 0, NET_DM_GRP_ALERT, GFP_KERNEL); |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 141 | |
Neil Horman | 3885ca7 | 2012-04-27 10:11:49 +0000 | [diff] [blame] | 142 | put_cpu_var(dm_cpu_data); |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 143 | } |
| 144 | |
| 145 | /* |
| 146 | * This is the timer function to delay the sending of an alert |
| 147 | * in the event that more drops will arrive during the |
| 148 | * hysteresis period. Note that it operates under the timer interrupt |
| 149 | * so we don't need to disable preemption here |
| 150 | */ |
| 151 | static void sched_send_work(unsigned long unused) |
| 152 | { |
Neil Horman | 3885ca7 | 2012-04-27 10:11:49 +0000 | [diff] [blame] | 153 | struct per_cpu_dm_data *data = &get_cpu_var(dm_cpu_data); |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 154 | |
Neil Horman | 3885ca7 | 2012-04-27 10:11:49 +0000 | [diff] [blame] | 155 | schedule_work_on(smp_processor_id(), &data->dm_alert_work); |
| 156 | |
| 157 | put_cpu_var(dm_cpu_data); |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 158 | } |
| 159 | |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 160 | static void trace_drop_common(struct sk_buff *skb, void *location) |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 161 | { |
| 162 | struct net_dm_alert_msg *msg; |
| 163 | struct nlmsghdr *nlh; |
Neil Horman | 683703a | 2009-04-27 03:17:31 -0700 | [diff] [blame] | 164 | struct nlattr *nla; |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 165 | int i; |
Neil Horman | 3885ca7 | 2012-04-27 10:11:49 +0000 | [diff] [blame] | 166 | struct sk_buff *dskb; |
| 167 | struct per_cpu_dm_data *data = &get_cpu_var(dm_cpu_data); |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 168 | |
| 169 | |
Neil Horman | 3885ca7 | 2012-04-27 10:11:49 +0000 | [diff] [blame] | 170 | rcu_read_lock(); |
| 171 | dskb = rcu_dereference(data->skb); |
| 172 | |
| 173 | if (!dskb) |
| 174 | goto out; |
| 175 | |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 176 | if (!atomic_add_unless(&data->dm_hit_count, -1, 0)) { |
| 177 | /* |
| 178 | * we're already at zero, discard this hit |
| 179 | */ |
| 180 | goto out; |
| 181 | } |
| 182 | |
Neil Horman | 3885ca7 | 2012-04-27 10:11:49 +0000 | [diff] [blame] | 183 | nlh = (struct nlmsghdr *)dskb->data; |
Neil Horman | 683703a | 2009-04-27 03:17:31 -0700 | [diff] [blame] | 184 | nla = genlmsg_data(nlmsg_data(nlh)); |
| 185 | msg = nla_data(nla); |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 186 | for (i = 0; i < msg->entries; i++) { |
| 187 | if (!memcmp(&location, msg->points[i].pc, sizeof(void *))) { |
| 188 | msg->points[i].count++; |
Eric Dumazet | bbe362b | 2012-04-19 07:16:21 +0000 | [diff] [blame] | 189 | atomic_inc(&data->dm_hit_count); |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 190 | goto out; |
| 191 | } |
| 192 | } |
| 193 | |
| 194 | /* |
| 195 | * We need to create a new entry |
| 196 | */ |
Neil Horman | 3885ca7 | 2012-04-27 10:11:49 +0000 | [diff] [blame] | 197 | __nla_reserve_nohdr(dskb, sizeof(struct net_dm_drop_point)); |
Neil Horman | 683703a | 2009-04-27 03:17:31 -0700 | [diff] [blame] | 198 | nla->nla_len += NLA_ALIGN(sizeof(struct net_dm_drop_point)); |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 199 | memcpy(msg->points[msg->entries].pc, &location, sizeof(void *)); |
| 200 | msg->points[msg->entries].count = 1; |
| 201 | msg->entries++; |
| 202 | |
| 203 | if (!timer_pending(&data->send_timer)) { |
| 204 | data->send_timer.expires = jiffies + dm_delay * HZ; |
| 205 | add_timer_on(&data->send_timer, smp_processor_id()); |
| 206 | } |
| 207 | |
| 208 | out: |
Neil Horman | 3885ca7 | 2012-04-27 10:11:49 +0000 | [diff] [blame] | 209 | rcu_read_unlock(); |
| 210 | put_cpu_var(dm_cpu_data); |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 211 | return; |
| 212 | } |
| 213 | |
Steven Rostedt | 38516ab | 2010-04-20 17:04:50 -0400 | [diff] [blame] | 214 | static void trace_kfree_skb_hit(void *ignore, struct sk_buff *skb, void *location) |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 215 | { |
| 216 | trace_drop_common(skb, location); |
| 217 | } |
| 218 | |
Steven Rostedt | 38516ab | 2010-04-20 17:04:50 -0400 | [diff] [blame] | 219 | static void trace_napi_poll_hit(void *ignore, struct napi_struct *napi) |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 220 | { |
| 221 | struct dm_hw_stat_delta *new_stat; |
| 222 | |
| 223 | /* |
Neil Horman | 5848cc0 | 2009-09-02 14:37:45 -0700 | [diff] [blame] | 224 | * Don't check napi structures with no associated device |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 225 | */ |
Neil Horman | 5848cc0 | 2009-09-02 14:37:45 -0700 | [diff] [blame] | 226 | if (!napi->dev) |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 227 | return; |
| 228 | |
| 229 | rcu_read_lock(); |
| 230 | list_for_each_entry_rcu(new_stat, &hw_stats_list, list) { |
Neil Horman | 5848cc0 | 2009-09-02 14:37:45 -0700 | [diff] [blame] | 231 | /* |
| 232 | * only add a note to our monitor buffer if: |
| 233 | * 1) this is the dev we received on |
| 234 | * 2) its after the last_rx delta |
| 235 | * 3) our rx_dropped count has gone up |
| 236 | */ |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 237 | if ((new_stat->dev == napi->dev) && |
Neil Horman | 5848cc0 | 2009-09-02 14:37:45 -0700 | [diff] [blame] | 238 | (time_after(jiffies, new_stat->last_rx + dm_hw_check_delta)) && |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 239 | (napi->dev->stats.rx_dropped != new_stat->last_drop_val)) { |
| 240 | trace_drop_common(NULL, NULL); |
| 241 | new_stat->last_drop_val = napi->dev->stats.rx_dropped; |
Neil Horman | 5848cc0 | 2009-09-02 14:37:45 -0700 | [diff] [blame] | 242 | new_stat->last_rx = jiffies; |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 243 | break; |
| 244 | } |
| 245 | } |
| 246 | rcu_read_unlock(); |
| 247 | } |
| 248 | |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 249 | static int set_all_monitor_traces(int state) |
| 250 | { |
| 251 | int rc = 0; |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 252 | struct dm_hw_stat_delta *new_stat = NULL; |
| 253 | struct dm_hw_stat_delta *temp; |
| 254 | |
Neil Horman | cde2e9a | 2012-04-27 10:11:48 +0000 | [diff] [blame] | 255 | mutex_lock(&trace_state_mutex); |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 256 | |
Neil Horman | 4b70637 | 2010-07-20 04:52:09 +0000 | [diff] [blame] | 257 | if (state == trace_state) { |
| 258 | rc = -EAGAIN; |
| 259 | goto out_unlock; |
| 260 | } |
| 261 | |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 262 | switch (state) { |
| 263 | case TRACE_ON: |
Steven Rostedt | 38516ab | 2010-04-20 17:04:50 -0400 | [diff] [blame] | 264 | rc |= register_trace_kfree_skb(trace_kfree_skb_hit, NULL); |
| 265 | rc |= register_trace_napi_poll(trace_napi_poll_hit, NULL); |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 266 | break; |
| 267 | case TRACE_OFF: |
Steven Rostedt | 38516ab | 2010-04-20 17:04:50 -0400 | [diff] [blame] | 268 | rc |= unregister_trace_kfree_skb(trace_kfree_skb_hit, NULL); |
| 269 | rc |= unregister_trace_napi_poll(trace_napi_poll_hit, NULL); |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 270 | |
| 271 | tracepoint_synchronize_unregister(); |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 272 | |
| 273 | /* |
| 274 | * Clean the device list |
| 275 | */ |
| 276 | list_for_each_entry_safe(new_stat, temp, &hw_stats_list, list) { |
| 277 | if (new_stat->dev == NULL) { |
| 278 | list_del_rcu(&new_stat->list); |
Lai Jiangshan | fa81c0e | 2011-03-18 11:39:43 +0800 | [diff] [blame] | 279 | kfree_rcu(new_stat, rcu); |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 280 | } |
| 281 | } |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 282 | break; |
| 283 | default: |
| 284 | rc = 1; |
| 285 | break; |
| 286 | } |
| 287 | |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 288 | if (!rc) |
| 289 | trace_state = state; |
Neil Horman | 4b70637 | 2010-07-20 04:52:09 +0000 | [diff] [blame] | 290 | else |
| 291 | rc = -EINPROGRESS; |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 292 | |
Neil Horman | 4b70637 | 2010-07-20 04:52:09 +0000 | [diff] [blame] | 293 | out_unlock: |
Neil Horman | cde2e9a | 2012-04-27 10:11:48 +0000 | [diff] [blame] | 294 | mutex_unlock(&trace_state_mutex); |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 295 | |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 296 | return rc; |
| 297 | } |
| 298 | |
| 299 | |
| 300 | static int net_dm_cmd_config(struct sk_buff *skb, |
| 301 | struct genl_info *info) |
| 302 | { |
| 303 | return -ENOTSUPP; |
| 304 | } |
| 305 | |
| 306 | static int net_dm_cmd_trace(struct sk_buff *skb, |
| 307 | struct genl_info *info) |
| 308 | { |
| 309 | switch (info->genlhdr->cmd) { |
| 310 | case NET_DM_CMD_START: |
| 311 | return set_all_monitor_traces(TRACE_ON); |
| 312 | break; |
| 313 | case NET_DM_CMD_STOP: |
| 314 | return set_all_monitor_traces(TRACE_OFF); |
| 315 | break; |
| 316 | } |
| 317 | |
| 318 | return -ENOTSUPP; |
| 319 | } |
| 320 | |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 321 | static int dropmon_net_event(struct notifier_block *ev_block, |
| 322 | unsigned long event, void *ptr) |
| 323 | { |
| 324 | struct net_device *dev = ptr; |
| 325 | struct dm_hw_stat_delta *new_stat = NULL; |
| 326 | struct dm_hw_stat_delta *tmp; |
| 327 | |
| 328 | switch (event) { |
| 329 | case NETDEV_REGISTER: |
| 330 | new_stat = kzalloc(sizeof(struct dm_hw_stat_delta), GFP_KERNEL); |
| 331 | |
| 332 | if (!new_stat) |
| 333 | goto out; |
| 334 | |
| 335 | new_stat->dev = dev; |
Neil Horman | 5848cc0 | 2009-09-02 14:37:45 -0700 | [diff] [blame] | 336 | new_stat->last_rx = jiffies; |
Neil Horman | cde2e9a | 2012-04-27 10:11:48 +0000 | [diff] [blame] | 337 | mutex_lock(&trace_state_mutex); |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 338 | list_add_rcu(&new_stat->list, &hw_stats_list); |
Neil Horman | cde2e9a | 2012-04-27 10:11:48 +0000 | [diff] [blame] | 339 | mutex_unlock(&trace_state_mutex); |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 340 | break; |
| 341 | case NETDEV_UNREGISTER: |
Neil Horman | cde2e9a | 2012-04-27 10:11:48 +0000 | [diff] [blame] | 342 | mutex_lock(&trace_state_mutex); |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 343 | list_for_each_entry_safe(new_stat, tmp, &hw_stats_list, list) { |
| 344 | if (new_stat->dev == dev) { |
| 345 | new_stat->dev = NULL; |
| 346 | if (trace_state == TRACE_OFF) { |
| 347 | list_del_rcu(&new_stat->list); |
Lai Jiangshan | fa81c0e | 2011-03-18 11:39:43 +0800 | [diff] [blame] | 348 | kfree_rcu(new_stat, rcu); |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 349 | break; |
| 350 | } |
| 351 | } |
| 352 | } |
Neil Horman | cde2e9a | 2012-04-27 10:11:48 +0000 | [diff] [blame] | 353 | mutex_unlock(&trace_state_mutex); |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 354 | break; |
| 355 | } |
| 356 | out: |
| 357 | return NOTIFY_DONE; |
| 358 | } |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 359 | |
| 360 | static struct genl_ops dropmon_ops[] = { |
| 361 | { |
| 362 | .cmd = NET_DM_CMD_CONFIG, |
| 363 | .doit = net_dm_cmd_config, |
| 364 | }, |
| 365 | { |
| 366 | .cmd = NET_DM_CMD_START, |
| 367 | .doit = net_dm_cmd_trace, |
| 368 | }, |
| 369 | { |
| 370 | .cmd = NET_DM_CMD_STOP, |
| 371 | .doit = net_dm_cmd_trace, |
| 372 | }, |
| 373 | }; |
| 374 | |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 375 | static struct notifier_block dropmon_net_notifier = { |
| 376 | .notifier_call = dropmon_net_event |
| 377 | }; |
| 378 | |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 379 | static int __init init_net_drop_monitor(void) |
| 380 | { |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 381 | struct per_cpu_dm_data *data; |
Changli Gao | a256be7 | 2010-07-26 20:59:42 -0700 | [diff] [blame] | 382 | int cpu, rc; |
| 383 | |
Neil Horman | ac0a121 | 2011-03-21 18:20:26 -0700 | [diff] [blame] | 384 | printk(KERN_INFO "Initializing network drop monitor service\n"); |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 385 | |
| 386 | if (sizeof(void *) > 8) { |
| 387 | printk(KERN_ERR "Unable to store program counters on this arch, Drop monitor failed\n"); |
| 388 | return -ENOSPC; |
| 389 | } |
| 390 | |
Changli Gao | a256be7 | 2010-07-26 20:59:42 -0700 | [diff] [blame] | 391 | rc = genl_register_family_with_ops(&net_drop_monitor_family, |
| 392 | dropmon_ops, |
| 393 | ARRAY_SIZE(dropmon_ops)); |
| 394 | if (rc) { |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 395 | printk(KERN_ERR "Could not create drop monitor netlink family\n"); |
Changli Gao | a256be7 | 2010-07-26 20:59:42 -0700 | [diff] [blame] | 396 | return rc; |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 397 | } |
| 398 | |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 399 | rc = register_netdevice_notifier(&dropmon_net_notifier); |
| 400 | if (rc < 0) { |
| 401 | printk(KERN_CRIT "Failed to register netdevice notifier\n"); |
| 402 | goto out_unreg; |
| 403 | } |
| 404 | |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 405 | rc = 0; |
| 406 | |
| 407 | for_each_present_cpu(cpu) { |
| 408 | data = &per_cpu(dm_cpu_data, cpu); |
Neil Horman | 4fdcfa1 | 2012-05-01 08:18:02 +0000 | [diff] [blame^] | 409 | data->cpu = cpu; |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 410 | INIT_WORK(&data->dm_alert_work, send_dm_alert); |
| 411 | init_timer(&data->send_timer); |
| 412 | data->send_timer.data = cpu; |
| 413 | data->send_timer.function = sched_send_work; |
Neil Horman | 4fdcfa1 | 2012-05-01 08:18:02 +0000 | [diff] [blame^] | 414 | reset_per_cpu_data(data); |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 415 | } |
Neil Horman | 4ea7e38 | 2009-05-21 07:36:08 +0000 | [diff] [blame] | 416 | |
Neil Horman | 3885ca7 | 2012-04-27 10:11:49 +0000 | [diff] [blame] | 417 | |
Neil Horman | 9a8afc8 | 2009-03-11 09:51:26 +0000 | [diff] [blame] | 418 | goto out; |
| 419 | |
| 420 | out_unreg: |
| 421 | genl_unregister_family(&net_drop_monitor_family); |
| 422 | out: |
| 423 | return rc; |
| 424 | } |
| 425 | |
| 426 | late_initcall(init_net_drop_monitor); |