diff options
Diffstat (limited to 'net/core/drop_monitor.c')
-rw-r--r-- | net/core/drop_monitor.c | 730 |
1 files changed, 703 insertions, 27 deletions
diff --git a/net/core/drop_monitor.c b/net/core/drop_monitor.c index 39e094907391..cc60cc22e2db 100644 --- a/net/core/drop_monitor.c +++ b/net/core/drop_monitor.c @@ -26,6 +26,7 @@ #include <linux/bitops.h> #include <linux/slab.h> #include <linux/module.h> +#include <net/drop_monitor.h> #include <net/genetlink.h> #include <net/netevent.h> @@ -43,6 +44,7 @@ * netlink alerts */ static int trace_state = TRACE_OFF; +static bool monitor_hw; /* net_dm_mutex * @@ -56,9 +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; @@ -76,6 +95,7 @@ struct dm_hw_stat_delta { static struct genl_family net_drop_monitor_family; static DEFINE_PER_CPU(struct per_cpu_dm_data, dm_cpu_data); +static DEFINE_PER_CPU(struct per_cpu_dm_data, dm_hw_cpu_data); static int dm_hit_limit = 64; static int dm_delay = 1; @@ -92,10 +112,16 @@ struct net_dm_alert_ops { void (*napi_poll_probe)(void *ignore, struct napi_struct *napi, int work, int budget); void (*work_item_func)(struct work_struct *work); + void (*hw_work_item_func)(struct work_struct *work); + void (*hw_probe)(struct sk_buff *skb, + const struct net_dm_hw_metadata *hw_metadata); }; struct net_dm_skb_cb { - void *pc; + union { + struct net_dm_hw_metadata *hw_metadata; + void *pc; + }; }; #define NET_DM_SKB_CB(__skb) ((struct net_dm_skb_cb *)&((__skb)->cb[0])) @@ -266,10 +292,190 @@ 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, }; static void net_dm_packet_trace_kfree_skb_hit(void *ignore, @@ -323,7 +529,9 @@ static size_t net_dm_in_port_size(void) /* NET_DM_ATTR_IN_PORT nest */ return nla_total_size(0) + /* NET_DM_ATTR_PORT_NETDEV_IFINDEX */ - nla_total_size(sizeof(u32)); + nla_total_size(sizeof(u32)) + + /* NET_DM_ATTR_PORT_NETDEV_NAME */ + nla_total_size(IFNAMSIZ + 1); } #define NET_DM_MAX_SYMBOL_LEN 40 @@ -335,6 +543,8 @@ static size_t net_dm_packet_report_size(size_t payload_len) size = nlmsg_msg_size(GENL_HDRLEN + net_drop_monitor_family.hdrsize); return NLMSG_ALIGN(size) + + /* NET_DM_ATTR_ORIGIN */ + nla_total_size(sizeof(u16)) + /* NET_DM_ATTR_PC */ nla_total_size(sizeof(u64)) + /* NET_DM_ATTR_SYMBOL */ @@ -342,7 +552,7 @@ static size_t net_dm_packet_report_size(size_t payload_len) /* NET_DM_ATTR_IN_PORT */ net_dm_in_port_size() + /* NET_DM_ATTR_TIMESTAMP */ - nla_total_size(sizeof(struct timespec)) + + nla_total_size(sizeof(u64)) + /* NET_DM_ATTR_ORIG_LEN */ nla_total_size(sizeof(u32)) + /* NET_DM_ATTR_PROTO */ @@ -351,7 +561,8 @@ static size_t net_dm_packet_report_size(size_t payload_len) nla_total_size(payload_len); } -static int net_dm_packet_report_in_port_put(struct sk_buff *msg, int ifindex) +static int net_dm_packet_report_in_port_put(struct sk_buff *msg, int ifindex, + const char *name) { struct nlattr *attr; @@ -363,6 +574,9 @@ static int net_dm_packet_report_in_port_put(struct sk_buff *msg, int ifindex) nla_put_u32(msg, NET_DM_ATTR_PORT_NETDEV_IFINDEX, ifindex)) goto nla_put_failure; + if (name && nla_put_string(msg, NET_DM_ATTR_PORT_NETDEV_NAME, name)) + goto nla_put_failure; + nla_nest_end(msg, attr); return 0; @@ -378,7 +592,6 @@ static int net_dm_packet_report_fill(struct sk_buff *msg, struct sk_buff *skb, u64 pc = (u64)(uintptr_t) NET_DM_SKB_CB(skb)->pc; char buf[NET_DM_MAX_SYMBOL_LEN]; struct nlattr *attr; - struct timespec ts; void *hdr; int rc; @@ -387,6 +600,9 @@ static int net_dm_packet_report_fill(struct sk_buff *msg, struct sk_buff *skb, if (!hdr) return -EMSGSIZE; + if (nla_put_u16(msg, NET_DM_ATTR_ORIGIN, NET_DM_ORIGIN_SW)) + goto nla_put_failure; + if (nla_put_u64_64bit(msg, NET_DM_ATTR_PC, pc, NET_DM_ATTR_PAD)) goto nla_put_failure; @@ -394,12 +610,12 @@ static int net_dm_packet_report_fill(struct sk_buff *msg, struct sk_buff *skb, if (nla_put_string(msg, NET_DM_ATTR_SYMBOL, buf)) goto nla_put_failure; - rc = net_dm_packet_report_in_port_put(msg, skb->skb_iif); + rc = net_dm_packet_report_in_port_put(msg, skb->skb_iif, NULL); if (rc) goto nla_put_failure; - if (ktime_to_timespec_cond(skb->tstamp, &ts) && - nla_put(msg, NET_DM_ATTR_TIMESTAMP, sizeof(ts), &ts)) + if (nla_put_u64_64bit(msg, NET_DM_ATTR_TIMESTAMP, + ktime_to_ns(skb->tstamp), NET_DM_ATTR_PAD)) goto nla_put_failure; if (nla_put_u32(msg, NET_DM_ATTR_ORIG_LEN, skb->len)) @@ -481,10 +697,249 @@ static void net_dm_packet_work(struct work_struct *work) net_dm_packet_report(skb); } +static size_t +net_dm_hw_packet_report_size(size_t payload_len, + const struct net_dm_hw_metadata *hw_metadata) +{ + size_t size; + + size = nlmsg_msg_size(GENL_HDRLEN + net_drop_monitor_family.hdrsize); + + return NLMSG_ALIGN(size) + + /* NET_DM_ATTR_ORIGIN */ + nla_total_size(sizeof(u16)) + + /* NET_DM_ATTR_HW_TRAP_GROUP_NAME */ + nla_total_size(strlen(hw_metadata->trap_group_name) + 1) + + /* NET_DM_ATTR_HW_TRAP_NAME */ + nla_total_size(strlen(hw_metadata->trap_name) + 1) + + /* NET_DM_ATTR_IN_PORT */ + net_dm_in_port_size() + + /* NET_DM_ATTR_TIMESTAMP */ + nla_total_size(sizeof(u64)) + + /* NET_DM_ATTR_ORIG_LEN */ + nla_total_size(sizeof(u32)) + + /* NET_DM_ATTR_PROTO */ + nla_total_size(sizeof(u16)) + + /* NET_DM_ATTR_PAYLOAD */ + nla_total_size(payload_len); +} + +static int net_dm_hw_packet_report_fill(struct sk_buff *msg, + struct sk_buff *skb, size_t payload_len) +{ + struct net_dm_hw_metadata *hw_metadata; + struct nlattr *attr; + void *hdr; + + hw_metadata = NET_DM_SKB_CB(skb)->hw_metadata; + + hdr = genlmsg_put(msg, 0, 0, &net_drop_monitor_family, 0, + NET_DM_CMD_PACKET_ALERT); + if (!hdr) + return -EMSGSIZE; + + if (nla_put_u16(msg, NET_DM_ATTR_ORIGIN, NET_DM_ORIGIN_HW)) + goto nla_put_failure; + + if (nla_put_string(msg, NET_DM_ATTR_HW_TRAP_GROUP_NAME, + hw_metadata->trap_group_name)) + goto nla_put_failure; + + if (nla_put_string(msg, NET_DM_ATTR_HW_TRAP_NAME, + hw_metadata->trap_name)) + goto nla_put_failure; + + if (hw_metadata->input_dev) { + struct net_device *dev = hw_metadata->input_dev; + int rc; + + rc = net_dm_packet_report_in_port_put(msg, dev->ifindex, + dev->name); + if (rc) + goto nla_put_failure; + } + + if (nla_put_u64_64bit(msg, NET_DM_ATTR_TIMESTAMP, + ktime_to_ns(skb->tstamp), NET_DM_ATTR_PAD)) + goto nla_put_failure; + + if (nla_put_u32(msg, NET_DM_ATTR_ORIG_LEN, skb->len)) + goto nla_put_failure; + + if (!payload_len) + goto out; + + if (nla_put_u16(msg, NET_DM_ATTR_PROTO, be16_to_cpu(skb->protocol))) + goto nla_put_failure; + + attr = skb_put(msg, nla_total_size(payload_len)); + attr->nla_type = NET_DM_ATTR_PAYLOAD; + attr->nla_len = nla_attr_size(payload_len); + if (skb_copy_bits(skb, 0, nla_data(attr), payload_len)) + goto nla_put_failure; + +out: + genlmsg_end(msg, hdr); + + return 0; + +nla_put_failure: + genlmsg_cancel(msg, hdr); + return -EMSGSIZE; +} + +static struct net_dm_hw_metadata * +net_dm_hw_metadata_clone(const struct net_dm_hw_metadata *hw_metadata) +{ + struct net_dm_hw_metadata *n_hw_metadata; + const char *trap_group_name; + const char *trap_name; + + n_hw_metadata = kmalloc(sizeof(*hw_metadata), GFP_ATOMIC); + if (!n_hw_metadata) + return NULL; + + trap_group_name = kmemdup(hw_metadata->trap_group_name, + strlen(hw_metadata->trap_group_name) + 1, + GFP_ATOMIC | __GFP_ZERO); + if (!trap_group_name) + goto free_hw_metadata; + n_hw_metadata->trap_group_name = trap_group_name; + + trap_name = kmemdup(hw_metadata->trap_name, + strlen(hw_metadata->trap_name) + 1, + GFP_ATOMIC | __GFP_ZERO); + if (!trap_name) + goto free_trap_group; + n_hw_metadata->trap_name = trap_name; + + n_hw_metadata->input_dev = hw_metadata->input_dev; + if (n_hw_metadata->input_dev) + dev_hold(n_hw_metadata->input_dev); + + return n_hw_metadata; + +free_trap_group: + kfree(trap_group_name); +free_hw_metadata: + kfree(n_hw_metadata); + return NULL; +} + +static void +net_dm_hw_metadata_free(const struct net_dm_hw_metadata *hw_metadata) +{ + if (hw_metadata->input_dev) + dev_put(hw_metadata->input_dev); + kfree(hw_metadata->trap_name); + kfree(hw_metadata->trap_group_name); + kfree(hw_metadata); +} + +static void net_dm_hw_packet_report(struct sk_buff *skb) +{ + struct net_dm_hw_metadata *hw_metadata; + struct sk_buff *msg; + size_t payload_len; + int rc; + + if (skb->data > skb_mac_header(skb)) + skb_push(skb, skb->data - skb_mac_header(skb)); + else + skb_pull(skb, skb_mac_header(skb) - skb->data); + + payload_len = min_t(size_t, skb->len, NET_DM_MAX_PACKET_SIZE); + if (net_dm_trunc_len) + payload_len = min_t(size_t, net_dm_trunc_len, payload_len); + + hw_metadata = NET_DM_SKB_CB(skb)->hw_metadata; + msg = nlmsg_new(net_dm_hw_packet_report_size(payload_len, hw_metadata), + GFP_KERNEL); + if (!msg) + goto out; + + rc = net_dm_hw_packet_report_fill(msg, skb, payload_len); + if (rc) { + nlmsg_free(msg); + goto out; + } + + genlmsg_multicast(&net_drop_monitor_family, msg, 0, 0, GFP_KERNEL); + +out: + net_dm_hw_metadata_free(NET_DM_SKB_CB(skb)->hw_metadata); + consume_skb(skb); +} + +static void net_dm_hw_packet_work(struct work_struct *work) +{ + struct per_cpu_dm_data *hw_data; + struct sk_buff_head list; + struct sk_buff *skb; + unsigned long flags; + + hw_data = container_of(work, struct per_cpu_dm_data, dm_alert_work); + + __skb_queue_head_init(&list); + + spin_lock_irqsave(&hw_data->drop_queue.lock, flags); + skb_queue_splice_tail_init(&hw_data->drop_queue, &list); + spin_unlock_irqrestore(&hw_data->drop_queue.lock, flags); + + while ((skb = __skb_dequeue(&list))) + net_dm_hw_packet_report(skb); +} + +static void +net_dm_hw_packet_probe(struct sk_buff *skb, + const struct net_dm_hw_metadata *hw_metadata) +{ + struct net_dm_hw_metadata *n_hw_metadata; + ktime_t tstamp = ktime_get_real(); + struct per_cpu_dm_data *hw_data; + struct sk_buff *nskb; + unsigned long flags; + + nskb = skb_clone(skb, GFP_ATOMIC); + if (!nskb) + return; + + n_hw_metadata = net_dm_hw_metadata_clone(hw_metadata); + if (!n_hw_metadata) + goto free; + + NET_DM_SKB_CB(nskb)->hw_metadata = n_hw_metadata; + nskb->tstamp = tstamp; + + hw_data = this_cpu_ptr(&dm_hw_cpu_data); + + spin_lock_irqsave(&hw_data->drop_queue.lock, flags); + if (skb_queue_len(&hw_data->drop_queue) < net_dm_queue_len) + __skb_queue_tail(&hw_data->drop_queue, nskb); + else + goto unlock_free; + spin_unlock_irqrestore(&hw_data->drop_queue.lock, flags); + + schedule_work(&hw_data->dm_alert_work); + + return; + +unlock_free: + spin_unlock_irqrestore(&hw_data->drop_queue.lock, flags); + u64_stats_update_begin(&hw_data->stats.syncp); + hw_data->stats.dropped++; + u64_stats_update_end(&hw_data->stats.syncp); + net_dm_hw_metadata_free(n_hw_metadata); +free: + consume_skb(nskb); +} + static const struct net_dm_alert_ops net_dm_alert_packet_ops = { .kfree_skb_probe = net_dm_packet_trace_kfree_skb_hit, .napi_poll_probe = net_dm_packet_trace_napi_poll_hit, .work_item_func = net_dm_packet_work, + .hw_work_item_func = net_dm_hw_packet_work, + .hw_probe = net_dm_hw_packet_probe, }; static const struct net_dm_alert_ops *net_dm_alert_ops_arr[] = { @@ -492,6 +947,85 @@ static const struct net_dm_alert_ops *net_dm_alert_ops_arr[] = { [NET_DM_ALERT_MODE_PACKET] = &net_dm_alert_packet_ops, }; +void net_dm_hw_report(struct sk_buff *skb, + const struct net_dm_hw_metadata *hw_metadata) +{ + rcu_read_lock(); + + if (!monitor_hw) + goto out; + + net_dm_alert_ops_arr[net_dm_alert_mode]->hw_probe(skb, hw_metadata); + +out: + rcu_read_unlock(); +} +EXPORT_SYMBOL_GPL(net_dm_hw_report); + +static int net_dm_hw_monitor_start(struct netlink_ext_ack *extack) +{ + const struct net_dm_alert_ops *ops; + int cpu; + + if (monitor_hw) { + NL_SET_ERR_MSG_MOD(extack, "Hardware monitoring already enabled"); + return -EAGAIN; + } + + ops = net_dm_alert_ops_arr[net_dm_alert_mode]; + + if (!try_module_get(THIS_MODULE)) { + NL_SET_ERR_MSG_MOD(extack, "Failed to take reference on module"); + return -ENODEV; + } + + for_each_possible_cpu(cpu) { + struct per_cpu_dm_data *hw_data = &per_cpu(dm_hw_cpu_data, cpu); + struct net_dm_hw_entries *hw_entries; + + INIT_WORK(&hw_data->dm_alert_work, ops->hw_work_item_func); + timer_setup(&hw_data->send_timer, sched_send_work, 0); + hw_entries = net_dm_hw_reset_per_cpu_data(hw_data); + kfree(hw_entries); + } + + monitor_hw = true; + + return 0; +} + +static void net_dm_hw_monitor_stop(struct netlink_ext_ack *extack) +{ + int cpu; + + if (!monitor_hw) + NL_SET_ERR_MSG_MOD(extack, "Hardware monitoring already disabled"); + + monitor_hw = false; + + /* After this call returns we are guaranteed that no CPU is processing + * any hardware drops. + */ + synchronize_rcu(); + + for_each_possible_cpu(cpu) { + struct per_cpu_dm_data *hw_data = &per_cpu(dm_hw_cpu_data, cpu); + struct sk_buff *skb; + + del_timer_sync(&hw_data->send_timer); + cancel_work_sync(&hw_data->dm_alert_work); + while ((skb = __skb_dequeue(&hw_data->drop_queue))) { + struct net_dm_hw_metadata *hw_metadata; + + hw_metadata = NET_DM_SKB_CB(skb)->hw_metadata; + net_dm_hw_metadata_free(hw_metadata); + consume_skb(skb); + } + } + + module_put(THIS_MODULE); +} + static int net_dm_trace_on_set(struct netlink_ext_ack *extack) { const struct net_dm_alert_ops *ops; @@ -604,6 +1138,11 @@ static int set_all_monitor_traces(int state, struct netlink_ext_ack *extack) return rc; } +static bool net_dm_is_monitoring(void) +{ + return trace_state == TRACE_ON || monitor_hw; +} + static int net_dm_alert_mode_get_from_info(struct genl_info *info, enum net_dm_alert_mode *p_alert_mode) { @@ -665,8 +1204,8 @@ static int net_dm_cmd_config(struct sk_buff *skb, struct netlink_ext_ack *extack = info->extack; int rc; - if (trace_state == TRACE_ON) { - NL_SET_ERR_MSG_MOD(extack, "Cannot configure drop monitor while tracing is on"); + if (net_dm_is_monitoring()) { + NL_SET_ERR_MSG_MOD(extack, "Cannot configure drop monitor during monitoring"); return -EBUSY; } @@ -681,14 +1220,61 @@ static int net_dm_cmd_config(struct sk_buff *skb, return 0; } +static int net_dm_monitor_start(bool set_sw, bool set_hw, + struct netlink_ext_ack *extack) +{ + bool sw_set = false; + int rc; + + if (set_sw) { + rc = set_all_monitor_traces(TRACE_ON, extack); + if (rc) + return rc; + sw_set = true; + } + + if (set_hw) { + rc = net_dm_hw_monitor_start(extack); + if (rc) + goto err_monitor_hw; + } + + return 0; + +err_monitor_hw: + if (sw_set) + set_all_monitor_traces(TRACE_OFF, extack); + return rc; +} + +static void net_dm_monitor_stop(bool set_sw, bool set_hw, + struct netlink_ext_ack *extack) +{ + if (set_hw) + net_dm_hw_monitor_stop(extack); + if (set_sw) + set_all_monitor_traces(TRACE_OFF, extack); +} + static int net_dm_cmd_trace(struct sk_buff *skb, struct genl_info *info) { + bool set_sw = !!info->attrs[NET_DM_ATTR_SW_DROPS]; + bool set_hw = !!info->attrs[NET_DM_ATTR_HW_DROPS]; + struct netlink_ext_ack *extack = info->extack; + + /* To maintain backward compatibility, we start / stop monitoring of + * software drops if no flag is specified. + */ + if (!set_sw && !set_hw) + set_sw = true; + switch (info->genlhdr->cmd) { case NET_DM_CMD_START: - return set_all_monitor_traces(TRACE_ON, info->extack); + return net_dm_monitor_start(set_sw, set_hw, extack); case NET_DM_CMD_STOP: - return set_all_monitor_traces(TRACE_OFF, info->extack); + net_dm_monitor_stop(set_sw, set_hw, extack); + return 0; } return -EOPNOTSUPP; @@ -785,6 +1371,50 @@ nla_put_failure: return -EMSGSIZE; } +static void net_dm_hw_stats_read(struct net_dm_stats *stats) +{ + int cpu; + + memset(stats, 0, sizeof(*stats)); + for_each_possible_cpu(cpu) { + struct per_cpu_dm_data *hw_data = &per_cpu(dm_hw_cpu_data, cpu); + struct net_dm_stats *cpu_stats = &hw_data->stats; + unsigned int start; + u64 dropped; + + do { + start = u64_stats_fetch_begin_irq(&cpu_stats->syncp); + dropped = cpu_stats->dropped; + } while (u64_stats_fetch_retry_irq(&cpu_stats->syncp, start)); + + stats->dropped += dropped; + } +} + +static int net_dm_hw_stats_put(struct sk_buff *msg) +{ + struct net_dm_stats stats; + struct nlattr *attr; + + net_dm_hw_stats_read(&stats); + + attr = nla_nest_start(msg, NET_DM_ATTR_HW_STATS); + if (!attr) + return -EMSGSIZE; + + if (nla_put_u64_64bit(msg, NET_DM_ATTR_STATS_DROPPED, + stats.dropped, NET_DM_ATTR_PAD)) + 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_stats_fill(struct sk_buff *msg, struct genl_info *info) { void *hdr; @@ -799,6 +1429,10 @@ static int net_dm_stats_fill(struct sk_buff *msg, struct genl_info *info) if (rc) goto nla_put_failure; + rc = net_dm_hw_stats_put(msg); + if (rc) + goto nla_put_failure; + genlmsg_end(msg, hdr); return 0; @@ -872,6 +1506,8 @@ static const struct nla_policy net_dm_nl_policy[NET_DM_ATTR_MAX + 1] = { [NET_DM_ATTR_ALERT_MODE] = { .type = NLA_U8 }, [NET_DM_ATTR_TRUNC_LEN] = { .type = NLA_U32 }, [NET_DM_ATTR_QUEUE_LEN] = { .type = NLA_U32 }, + [NET_DM_ATTR_SW_DROPS] = {. type = NLA_FLAG }, + [NET_DM_ATTR_HW_DROPS] = {. type = NLA_FLAG }, }; static const struct genl_ops dropmon_ops[] = { @@ -934,9 +1570,57 @@ static struct notifier_block dropmon_net_notifier = { .notifier_call = dropmon_net_event }; -static int __init init_net_drop_monitor(void) +static void __net_dm_cpu_data_init(struct per_cpu_dm_data *data) +{ + spin_lock_init(&data->lock); + skb_queue_head_init(&data->drop_queue); + u64_stats_init(&data->stats.syncp); +} + +static void __net_dm_cpu_data_fini(struct per_cpu_dm_data *data) +{ + WARN_ON(!skb_queue_empty(&data->drop_queue)); +} + +static void net_dm_cpu_data_init(int cpu) +{ + struct per_cpu_dm_data *data; + + data = &per_cpu(dm_cpu_data, cpu); + __net_dm_cpu_data_init(data); +} + +static void net_dm_cpu_data_fini(int cpu) { struct per_cpu_dm_data *data; + + data = &per_cpu(dm_cpu_data, cpu); + /* At this point, we should have exclusive access + * to this struct and can free the skb inside it. + */ + consume_skb(data->skb); + __net_dm_cpu_data_fini(data); +} + +static void net_dm_hw_cpu_data_init(int cpu) +{ + struct per_cpu_dm_data *hw_data; + + hw_data = &per_cpu(dm_hw_cpu_data, cpu); + __net_dm_cpu_data_init(hw_data); +} + +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); +} + +static int __init init_net_drop_monitor(void) +{ int cpu, rc; pr_info("Initializing network drop monitor service\n"); @@ -962,10 +1646,8 @@ static int __init init_net_drop_monitor(void) rc = 0; for_each_possible_cpu(cpu) { - data = &per_cpu(dm_cpu_data, cpu); - spin_lock_init(&data->lock); - skb_queue_head_init(&data->drop_queue); - u64_stats_init(&data->stats.syncp); + net_dm_cpu_data_init(cpu); + net_dm_hw_cpu_data_init(cpu); } goto out; @@ -978,7 +1660,6 @@ out: static void exit_net_drop_monitor(void) { - struct per_cpu_dm_data *data; int cpu; BUG_ON(unregister_netdevice_notifier(&dropmon_net_notifier)); @@ -989,13 +1670,8 @@ static void exit_net_drop_monitor(void) */ for_each_possible_cpu(cpu) { - data = &per_cpu(dm_cpu_data, cpu); - /* - * At this point, we should have exclusive access - * to this struct and can free the skb inside it - */ - kfree_skb(data->skb); - WARN_ON(!skb_queue_empty(&data->drop_queue)); + net_dm_hw_cpu_data_fini(cpu); + net_dm_cpu_data_fini(cpu); } BUG_ON(genl_unregister_family(&net_drop_monitor_family)); |