1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Data gathering module for Linux-VM Monitor Stream, Stage 1.
4 * Collects misc. OS related data (CPU utilization, running processes).
5 *
6 * Copyright IBM Corp. 2003, 2006
7 *
8 * Author: Gerald Schaefer <gerald.schaefer@de.ibm.com>
9 */
10
11#define KMSG_COMPONENT	"appldata"
12#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
13
14#include <linux/module.h>
15#include <linux/init.h>
16#include <linux/slab.h>
17#include <linux/errno.h>
18#include <linux/kernel_stat.h>
19#include <linux/netdevice.h>
20#include <linux/sched.h>
21#include <linux/sched/loadavg.h>
22#include <linux/sched/stat.h>
23#include <asm/appldata.h>
24#include <asm/smp.h>
25
26#include "appldata.h"
27
28/*
29 * OS data
30 *
31 * This is accessed as binary data by z/VM. If changes to it can't be avoided,
32 * the structure version (product ID, see appldata_base.c) needs to be changed
33 * as well and all documentation and z/VM applications using it must be
34 * updated.
35 */
36struct appldata_os_per_cpu {
37	u32 per_cpu_user;	/* timer ticks spent in user mode   */
38	u32 per_cpu_nice;	/* ... spent with modified priority */
39	u32 per_cpu_system;	/* ... spent in kernel mode         */
40	u32 per_cpu_idle;	/* ... spent in idle mode           */
41
42	/* New in 2.6 */
43	u32 per_cpu_irq;	/* ... spent in interrupts          */
44	u32 per_cpu_softirq;	/* ... spent in softirqs            */
45	u32 per_cpu_iowait;	/* ... spent while waiting for I/O  */
46
47	/* New in modification level 01 */
48	u32 per_cpu_steal;	/* ... stolen by hypervisor	    */
49	u32 cpu_id;		/* number of this CPU		    */
50} __attribute__((packed));
51
52struct appldata_os_data {
53	u64 timestamp;
54	u32 sync_count_1;	/* after VM collected the record data, */
55	u32 sync_count_2;	/* sync_count_1 and sync_count_2 should be the
56				   same. If not, the record has been updated on
57				   the Linux side while VM was collecting the
58				   (possibly corrupt) data */
59
60	u32 nr_cpus;		/* number of (virtual) CPUs        */
61	u32 per_cpu_size;	/* size of the per-cpu data struct */
62	u32 cpu_offset;		/* offset of the first per-cpu data struct */
63
64	u32 nr_running;		/* number of runnable threads      */
65	u32 nr_threads;		/* number of threads               */
66	u32 avenrun[3];		/* average nr. of running processes during */
67				/* the last 1, 5 and 15 minutes */
68
69	/* New in 2.6 */
70	u32 nr_iowait;		/* number of blocked threads
71				   (waiting for I/O)               */
72
73	/* per cpu data */
74	struct appldata_os_per_cpu os_cpu[];
75} __attribute__((packed));
76
77static struct appldata_os_data *appldata_os_data;
78
79static struct appldata_ops ops = {
80	.name	   = "os",
81	.record_nr = APPLDATA_RECORD_OS_ID,
82	.owner	   = THIS_MODULE,
83	.mod_lvl   = {0xF0, 0xF1},		/* EBCDIC "01" */
84};
85
86
87/*
88 * appldata_get_os_data()
89 *
90 * gather OS data
91 */
92static void appldata_get_os_data(void *data)
93{
94	int i, j, rc;
95	struct appldata_os_data *os_data;
96	unsigned int new_size;
97
98	os_data = data;
99	os_data->sync_count_1++;
100
101	os_data->nr_threads = nr_threads;
102	os_data->nr_running = nr_running();
103	os_data->nr_iowait  = nr_iowait();
104	os_data->avenrun[0] = avenrun[0] + (FIXED_1/200);
105	os_data->avenrun[1] = avenrun[1] + (FIXED_1/200);
106	os_data->avenrun[2] = avenrun[2] + (FIXED_1/200);
107
108	j = 0;
109	for_each_online_cpu(i) {
110		os_data->os_cpu[j].per_cpu_user =
111			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_USER]);
112		os_data->os_cpu[j].per_cpu_nice =
113			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_NICE]);
114		os_data->os_cpu[j].per_cpu_system =
115			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_SYSTEM]);
116		os_data->os_cpu[j].per_cpu_idle =
117			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_IDLE]);
118		os_data->os_cpu[j].per_cpu_irq =
119			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_IRQ]);
120		os_data->os_cpu[j].per_cpu_softirq =
121			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_SOFTIRQ]);
122		os_data->os_cpu[j].per_cpu_iowait =
123			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_IOWAIT]);
124		os_data->os_cpu[j].per_cpu_steal =
125			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_STEAL]);
126		os_data->os_cpu[j].cpu_id = i;
127		j++;
128	}
129
130	os_data->nr_cpus = j;
131
132	new_size = struct_size(os_data, os_cpu, os_data->nr_cpus);
133	if (ops.size != new_size) {
134		if (ops.active) {
135			rc = appldata_diag(APPLDATA_RECORD_OS_ID,
136					   APPLDATA_START_INTERVAL_REC,
137					   (unsigned long) ops.data, new_size,
138					   ops.mod_lvl);
139			if (rc != 0)
140				pr_err("Starting a new OS data collection "
141				       "failed with rc=%d\n", rc);
142
143			rc = appldata_diag(APPLDATA_RECORD_OS_ID,
144					   APPLDATA_STOP_REC,
145					   (unsigned long) ops.data, ops.size,
146					   ops.mod_lvl);
147			if (rc != 0)
148				pr_err("Stopping a faulty OS data "
149				       "collection failed with rc=%d\n", rc);
150		}
151		ops.size = new_size;
152	}
153	os_data->timestamp = get_tod_clock();
154	os_data->sync_count_2++;
155}
156
157
158/*
159 * appldata_os_init()
160 *
161 * init data, register ops
162 */
163static int __init appldata_os_init(void)
164{
165	int rc, max_size;
166
167	max_size = struct_size(appldata_os_data, os_cpu, num_possible_cpus());
168	if (max_size > APPLDATA_MAX_REC_SIZE) {
169		pr_err("Maximum OS record size %i exceeds the maximum "
170		       "record size %i\n", max_size, APPLDATA_MAX_REC_SIZE);
171		rc = -ENOMEM;
172		goto out;
173	}
174
175	appldata_os_data = kzalloc(max_size, GFP_KERNEL | GFP_DMA);
176	if (appldata_os_data == NULL) {
177		rc = -ENOMEM;
178		goto out;
179	}
180
181	appldata_os_data->per_cpu_size = sizeof(struct appldata_os_per_cpu);
182	appldata_os_data->cpu_offset   = offsetof(struct appldata_os_data,
183							os_cpu);
184
185	ops.data = appldata_os_data;
186	ops.callback  = &appldata_get_os_data;
187	rc = appldata_register_ops(&ops);
188	if (rc != 0)
189		kfree(appldata_os_data);
190out:
191	return rc;
192}
193
194/*
195 * appldata_os_exit()
196 *
197 * unregister ops
198 */
199static void __exit appldata_os_exit(void)
200{
201	appldata_unregister_ops(&ops);
202	kfree(appldata_os_data);
203}
204
205
206module_init(appldata_os_init);
207module_exit(appldata_os_exit);
208
209MODULE_LICENSE("GPL");
210MODULE_AUTHOR("Gerald Schaefer");
211MODULE_DESCRIPTION("Linux-VM Monitor Stream, OS statistics");
212