Commit 5855357c authored by Ido Schimmel's avatar Ido Schimmel Committed by David S. Miller
Browse files

drop_monitor: Prepare probe functions for devlink tracepoint 



Drop monitor supports two alerting modes: Summary and packet. Prepare a
probe function for each, so that they could be later registered on the
devlink tracepoint by calling register_trace_devlink_trap_report(),
based on the configured alerting mode.

Signed-off-by: default avatarIdo Schimmel <idosch@mellanox.com>
Reviewed-by: default avatarJiri Pirko <jiri@mellanox.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 5b88823b

net/core/drop_monitor.c

+146 −0
Original line number Diff line number Diff line
@@ -30,6 +30,7 @@ 
#include <net/genetlink.h>

#include <net/netevent.h>

#include <net/flow_offload.h>

#include <net/devlink.h>



#include <trace/events/skb.h>

#include <trace/events/napi.h>
@@ -116,6 +117,9 @@ struct net_dm_alert_ops { 
	void (*hw_work_item_func)(struct work_struct *work);

	void (*hw_probe)(struct sk_buff *skb,

			 const struct net_dm_hw_metadata *hw_metadata);

	void (*hw_trap_probe)(void *ignore, const struct devlink *devlink,

			      struct sk_buff *skb,

			      const struct devlink_trap_metadata *metadata);

};



struct net_dm_skb_cb {
@@ -474,12 +478,57 @@ net_dm_hw_summary_probe(struct sk_buff *skb, 
	spin_unlock_irqrestore(&hw_data->lock, flags);

}



static void

net_dm_hw_trap_summary_probe(void *ignore, const struct devlink *devlink,

			     struct sk_buff *skb,

			     const struct devlink_trap_metadata *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, 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, 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,

	.hw_trap_probe		= net_dm_hw_trap_summary_probe,

};



static void net_dm_packet_trace_kfree_skb_hit(void *ignore,
@@ -858,6 +907,54 @@ net_dm_hw_metadata_clone(const struct net_dm_hw_metadata *hw_metadata) 
	return NULL;

}



static struct net_dm_hw_metadata *

net_dm_hw_metadata_copy(const struct devlink_trap_metadata *metadata)

{

	const struct flow_action_cookie *fa_cookie;

	struct net_dm_hw_metadata *hw_metadata;

	const char *trap_group_name;

	const char *trap_name;



	hw_metadata = kzalloc(sizeof(*hw_metadata), GFP_ATOMIC);

	if (!hw_metadata)

		return NULL;



	trap_group_name = kstrdup(metadata->trap_group_name, GFP_ATOMIC);

	if (!trap_group_name)

		goto free_hw_metadata;

	hw_metadata->trap_group_name = trap_group_name;



	trap_name = kstrdup(metadata->trap_name, GFP_ATOMIC);

	if (!trap_name)

		goto free_trap_group;

	hw_metadata->trap_name = trap_name;



	if (metadata->fa_cookie) {

		size_t cookie_size = sizeof(*fa_cookie) +

				     metadata->fa_cookie->cookie_len;



		fa_cookie = kmemdup(metadata->fa_cookie, cookie_size,

				    GFP_ATOMIC);

		if (!fa_cookie)

			goto free_trap_name;

		hw_metadata->fa_cookie = fa_cookie;

	}



	hw_metadata->input_dev = metadata->input_dev;

	if (hw_metadata->input_dev)

		dev_hold(hw_metadata->input_dev);



	return hw_metadata;



free_trap_name:

	kfree(trap_name);

free_trap_group:

	kfree(trap_group_name);

free_hw_metadata:

	kfree(hw_metadata);

	return NULL;

}



static void

net_dm_hw_metadata_free(const struct net_dm_hw_metadata *hw_metadata)

{
@@ -970,12 +1067,61 @@ net_dm_hw_packet_probe(struct sk_buff *skb, 
	consume_skb(nskb);

}



static void

net_dm_hw_trap_packet_probe(void *ignore, const struct devlink *devlink,

			    struct sk_buff *skb,

			    const struct devlink_trap_metadata *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;



	if (!skb_mac_header_was_set(skb))

		return;



	nskb = skb_clone(skb, GFP_ATOMIC);

	if (!nskb)

		return;



	n_hw_metadata = net_dm_hw_metadata_copy(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,

	.hw_trap_probe		= net_dm_hw_trap_packet_probe,

};



static const struct net_dm_alert_ops *net_dm_alert_ops_arr[] = {