appldata_net_sum.c

  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Data gathering module for Linux-VM Monitor Stream, Stage 1.
  4 * Collects accumulated network statistics (Packets received/transmitted,
  5 * dropped, errors, ...).
  6 *
  7 * Copyright IBM Corp. 2003, 2006
  8 *
  9 * Author: Gerald Schaefer <gerald.schaefer@de.ibm.com>
 10 */
 11
 12#include <linux/module.h>
 13#include <linux/init.h>
 14#include <linux/errno.h>
 15#include <linux/kernel_stat.h>
 16#include <linux/netdevice.h>
 17#include <net/net_namespace.h>
 18
 19#include "appldata.h"
 20
 21
 22/*
 23 * Network data
 24 *
 25 * This is accessed as binary data by z/VM. If changes to it can't be avoided,
 26 * the structure version (product ID, see appldata_base.c) needs to be changed
 27 * as well and all documentation and z/VM applications using it must be updated.
 28 */
 29struct appldata_net_sum_data {
 30	u64 timestamp;
 31	u32 sync_count_1;	/* after VM collected the record data, */
 32	u32 sync_count_2;	/* sync_count_1 and sync_count_2 should be the
 33				   same. If not, the record has been updated on
 34				   the Linux side while VM was collecting the
 35				   (possibly corrupt) data */
 36
 37	u32 nr_interfaces;	/* nr. of network interfaces being monitored */
 38
 39	u32 padding;		/* next value is 64-bit aligned, so these */
 40				/* 4 byte would be padded out by compiler */
 41
 42	u64 rx_packets;		/* total packets received        */
 43	u64 tx_packets;		/* total packets transmitted     */
 44	u64 rx_bytes;		/* total bytes received          */
 45	u64 tx_bytes;		/* total bytes transmitted       */
 46	u64 rx_errors;		/* bad packets received          */
 47	u64 tx_errors;		/* packet transmit problems      */
 48	u64 rx_dropped;		/* no space in linux buffers     */
 49	u64 tx_dropped;		/* no space available in linux   */
 50	u64 collisions;		/* collisions while transmitting */
 51} __packed;
 52
 53
 54/*
 55 * appldata_get_net_sum_data()
 56 *
 57 * gather accumulated network statistics
 58 */
 59static void appldata_get_net_sum_data(void *data)
 60{
 61	int i;
 62	struct appldata_net_sum_data *net_data;
 63	struct net_device *dev;
 64	unsigned long rx_packets, tx_packets, rx_bytes, tx_bytes, rx_errors,
 65			tx_errors, rx_dropped, tx_dropped, collisions;
 66
 67	net_data = data;
 68	net_data->sync_count_1++;
 69
 70	i = 0;
 71	rx_packets = 0;
 72	tx_packets = 0;
 73	rx_bytes   = 0;
 74	tx_bytes   = 0;
 75	rx_errors  = 0;
 76	tx_errors  = 0;
 77	rx_dropped = 0;
 78	tx_dropped = 0;
 79	collisions = 0;
 80
 81	rcu_read_lock();
 82	for_each_netdev_rcu(&init_net, dev) {
 83		const struct rtnl_link_stats64 *stats;
 84		struct rtnl_link_stats64 temp;
 85
 86		stats = dev_get_stats(dev, &temp);
 87		rx_packets += stats->rx_packets;
 88		tx_packets += stats->tx_packets;
 89		rx_bytes   += stats->rx_bytes;
 90		tx_bytes   += stats->tx_bytes;
 91		rx_errors  += stats->rx_errors;
 92		tx_errors  += stats->tx_errors;
 93		rx_dropped += stats->rx_dropped;
 94		tx_dropped += stats->tx_dropped;
 95		collisions += stats->collisions;
 96		i++;
 97	}
 98	rcu_read_unlock();
 99
100	net_data->nr_interfaces = i;
101	net_data->rx_packets = rx_packets;
102	net_data->tx_packets = tx_packets;
103	net_data->rx_bytes   = rx_bytes;
104	net_data->tx_bytes   = tx_bytes;
105	net_data->rx_errors  = rx_errors;
106	net_data->tx_errors  = tx_errors;
107	net_data->rx_dropped = rx_dropped;
108	net_data->tx_dropped = tx_dropped;
109	net_data->collisions = collisions;
110
111	net_data->timestamp = get_tod_clock();
112	net_data->sync_count_2++;
113}
114
115
116static struct appldata_ops ops = {
117	.name	   = "net_sum",
118	.record_nr = APPLDATA_RECORD_NET_SUM_ID,
119	.size	   = sizeof(struct appldata_net_sum_data),
120	.callback  = &appldata_get_net_sum_data,
121	.owner     = THIS_MODULE,
122	.mod_lvl   = {0xF0, 0xF0},		/* EBCDIC "00" */
123};
124
125
126/*
127 * appldata_net_init()
128 *
129 * init data, register ops
130 */
131static int __init appldata_net_init(void)
132{
133	int ret;
134
135	ops.data = kzalloc(sizeof(struct appldata_net_sum_data), GFP_KERNEL);
136	if (!ops.data)
137		return -ENOMEM;
138
139	ret = appldata_register_ops(&ops);
140	if (ret)
141		kfree(ops.data);
142
143	return ret;
144}
145
146/*
147 * appldata_net_exit()
148 *
149 * unregister ops
150 */
151static void __exit appldata_net_exit(void)
152{
153	appldata_unregister_ops(&ops);
154	kfree(ops.data);
155}
156
157
158module_init(appldata_net_init);
159module_exit(appldata_net_exit);
160
161MODULE_LICENSE("GPL");
162MODULE_AUTHOR("Gerald Schaefer");
163MODULE_DESCRIPTION("Linux-VM Monitor Stream, accumulated network statistics");