xref: /openbmc/linux/arch/s390/appldata/appldata_os.c (revision 82e6fdd6)
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 #define LOAD_INT(x) ((x) >> FSHIFT)
30 #define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100)
31 
32 /*
33  * OS data
34  *
35  * This is accessed as binary data by z/VM. If changes to it can't be avoided,
36  * the structure version (product ID, see appldata_base.c) needs to be changed
37  * as well and all documentation and z/VM applications using it must be
38  * updated.
39  *
40  * The record layout is documented in the Linux for zSeries Device Drivers
41  * book:
42  * http://oss.software.ibm.com/developerworks/opensource/linux390/index.shtml
43  */
44 struct appldata_os_per_cpu {
45 	u32 per_cpu_user;	/* timer ticks spent in user mode   */
46 	u32 per_cpu_nice;	/* ... spent with modified priority */
47 	u32 per_cpu_system;	/* ... spent in kernel mode         */
48 	u32 per_cpu_idle;	/* ... spent in idle mode           */
49 
50 	/* New in 2.6 */
51 	u32 per_cpu_irq;	/* ... spent in interrupts          */
52 	u32 per_cpu_softirq;	/* ... spent in softirqs            */
53 	u32 per_cpu_iowait;	/* ... spent while waiting for I/O  */
54 
55 	/* New in modification level 01 */
56 	u32 per_cpu_steal;	/* ... stolen by hypervisor	    */
57 	u32 cpu_id;		/* number of this CPU		    */
58 } __attribute__((packed));
59 
60 struct appldata_os_data {
61 	u64 timestamp;
62 	u32 sync_count_1;	/* after VM collected the record data, */
63 	u32 sync_count_2;	/* sync_count_1 and sync_count_2 should be the
64 				   same. If not, the record has been updated on
65 				   the Linux side while VM was collecting the
66 				   (possibly corrupt) data */
67 
68 	u32 nr_cpus;		/* number of (virtual) CPUs        */
69 	u32 per_cpu_size;	/* size of the per-cpu data struct */
70 	u32 cpu_offset;		/* offset of the first per-cpu data struct */
71 
72 	u32 nr_running;		/* number of runnable threads      */
73 	u32 nr_threads;		/* number of threads               */
74 	u32 avenrun[3];		/* average nr. of running processes during */
75 				/* the last 1, 5 and 15 minutes */
76 
77 	/* New in 2.6 */
78 	u32 nr_iowait;		/* number of blocked threads
79 				   (waiting for I/O)               */
80 
81 	/* per cpu data */
82 	struct appldata_os_per_cpu os_cpu[0];
83 } __attribute__((packed));
84 
85 static struct appldata_os_data *appldata_os_data;
86 
87 static struct appldata_ops ops = {
88 	.name	   = "os",
89 	.record_nr = APPLDATA_RECORD_OS_ID,
90 	.owner	   = THIS_MODULE,
91 	.mod_lvl   = {0xF0, 0xF1},		/* EBCDIC "01" */
92 };
93 
94 
95 /*
96  * appldata_get_os_data()
97  *
98  * gather OS data
99  */
100 static void appldata_get_os_data(void *data)
101 {
102 	int i, j, rc;
103 	struct appldata_os_data *os_data;
104 	unsigned int new_size;
105 
106 	os_data = data;
107 	os_data->sync_count_1++;
108 
109 	os_data->nr_threads = nr_threads;
110 	os_data->nr_running = nr_running();
111 	os_data->nr_iowait  = nr_iowait();
112 	os_data->avenrun[0] = avenrun[0] + (FIXED_1/200);
113 	os_data->avenrun[1] = avenrun[1] + (FIXED_1/200);
114 	os_data->avenrun[2] = avenrun[2] + (FIXED_1/200);
115 
116 	j = 0;
117 	for_each_online_cpu(i) {
118 		os_data->os_cpu[j].per_cpu_user =
119 			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_USER]);
120 		os_data->os_cpu[j].per_cpu_nice =
121 			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_NICE]);
122 		os_data->os_cpu[j].per_cpu_system =
123 			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_SYSTEM]);
124 		os_data->os_cpu[j].per_cpu_idle =
125 			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_IDLE]);
126 		os_data->os_cpu[j].per_cpu_irq =
127 			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_IRQ]);
128 		os_data->os_cpu[j].per_cpu_softirq =
129 			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_SOFTIRQ]);
130 		os_data->os_cpu[j].per_cpu_iowait =
131 			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_IOWAIT]);
132 		os_data->os_cpu[j].per_cpu_steal =
133 			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_STEAL]);
134 		os_data->os_cpu[j].cpu_id = i;
135 		j++;
136 	}
137 
138 	os_data->nr_cpus = j;
139 
140 	new_size = sizeof(struct appldata_os_data) +
141 		   (os_data->nr_cpus * sizeof(struct appldata_os_per_cpu));
142 	if (ops.size != new_size) {
143 		if (ops.active) {
144 			rc = appldata_diag(APPLDATA_RECORD_OS_ID,
145 					   APPLDATA_START_INTERVAL_REC,
146 					   (unsigned long) ops.data, new_size,
147 					   ops.mod_lvl);
148 			if (rc != 0)
149 				pr_err("Starting a new OS data collection "
150 				       "failed with rc=%d\n", rc);
151 
152 			rc = appldata_diag(APPLDATA_RECORD_OS_ID,
153 					   APPLDATA_STOP_REC,
154 					   (unsigned long) ops.data, ops.size,
155 					   ops.mod_lvl);
156 			if (rc != 0)
157 				pr_err("Stopping a faulty OS data "
158 				       "collection failed with rc=%d\n", rc);
159 		}
160 		ops.size = new_size;
161 	}
162 	os_data->timestamp = get_tod_clock();
163 	os_data->sync_count_2++;
164 }
165 
166 
167 /*
168  * appldata_os_init()
169  *
170  * init data, register ops
171  */
172 static int __init appldata_os_init(void)
173 {
174 	int rc, max_size;
175 
176 	max_size = sizeof(struct appldata_os_data) +
177 		   (num_possible_cpus() * sizeof(struct appldata_os_per_cpu));
178 	if (max_size > APPLDATA_MAX_REC_SIZE) {
179 		pr_err("Maximum OS record size %i exceeds the maximum "
180 		       "record size %i\n", max_size, APPLDATA_MAX_REC_SIZE);
181 		rc = -ENOMEM;
182 		goto out;
183 	}
184 
185 	appldata_os_data = kzalloc(max_size, GFP_KERNEL | GFP_DMA);
186 	if (appldata_os_data == NULL) {
187 		rc = -ENOMEM;
188 		goto out;
189 	}
190 
191 	appldata_os_data->per_cpu_size = sizeof(struct appldata_os_per_cpu);
192 	appldata_os_data->cpu_offset   = offsetof(struct appldata_os_data,
193 							os_cpu);
194 
195 	ops.data = appldata_os_data;
196 	ops.callback  = &appldata_get_os_data;
197 	rc = appldata_register_ops(&ops);
198 	if (rc != 0)
199 		kfree(appldata_os_data);
200 out:
201 	return rc;
202 }
203 
204 /*
205  * appldata_os_exit()
206  *
207  * unregister ops
208  */
209 static void __exit appldata_os_exit(void)
210 {
211 	appldata_unregister_ops(&ops);
212 	kfree(appldata_os_data);
213 }
214 
215 
216 module_init(appldata_os_init);
217 module_exit(appldata_os_exit);
218 
219 MODULE_LICENSE("GPL");
220 MODULE_AUTHOR("Gerald Schaefer");
221 MODULE_DESCRIPTION("Linux-VM Monitor Stream, OS statistics");
222