xref: /linux/arch/s390/appldata/appldata_os.c (revision 24bce201d79807b668bf9d9e0aca801c5c0d5f78)
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  */
36 struct 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 
52 struct 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 
77 static struct appldata_os_data *appldata_os_data;
78 
79 static 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  */
92 static 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  */
163 static 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);
190 out:
191 	return rc;
192 }
193 
194 /*
195  * appldata_os_exit()
196  *
197  * unregister ops
198  */
199 static void __exit appldata_os_exit(void)
200 {
201 	appldata_unregister_ops(&ops);
202 	kfree(appldata_os_data);
203 }
204 
205 
206 module_init(appldata_os_init);
207 module_exit(appldata_os_exit);
208 
209 MODULE_LICENSE("GPL");
210 MODULE_AUTHOR("Gerald Schaefer");
211 MODULE_DESCRIPTION("Linux-VM Monitor Stream, OS statistics");
212