xref: /openbmc/linux/arch/s390/appldata/appldata_os.c (revision 15e3ae36)
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  * The record layout is documented in the Linux for zSeries Device Drivers
37  * book:
38  * http://oss.software.ibm.com/developerworks/opensource/linux390/index.shtml
39  */
40 struct appldata_os_per_cpu {
41 	u32 per_cpu_user;	/* timer ticks spent in user mode   */
42 	u32 per_cpu_nice;	/* ... spent with modified priority */
43 	u32 per_cpu_system;	/* ... spent in kernel mode         */
44 	u32 per_cpu_idle;	/* ... spent in idle mode           */
45 
46 	/* New in 2.6 */
47 	u32 per_cpu_irq;	/* ... spent in interrupts          */
48 	u32 per_cpu_softirq;	/* ... spent in softirqs            */
49 	u32 per_cpu_iowait;	/* ... spent while waiting for I/O  */
50 
51 	/* New in modification level 01 */
52 	u32 per_cpu_steal;	/* ... stolen by hypervisor	    */
53 	u32 cpu_id;		/* number of this CPU		    */
54 } __attribute__((packed));
55 
56 struct appldata_os_data {
57 	u64 timestamp;
58 	u32 sync_count_1;	/* after VM collected the record data, */
59 	u32 sync_count_2;	/* sync_count_1 and sync_count_2 should be the
60 				   same. If not, the record has been updated on
61 				   the Linux side while VM was collecting the
62 				   (possibly corrupt) data */
63 
64 	u32 nr_cpus;		/* number of (virtual) CPUs        */
65 	u32 per_cpu_size;	/* size of the per-cpu data struct */
66 	u32 cpu_offset;		/* offset of the first per-cpu data struct */
67 
68 	u32 nr_running;		/* number of runnable threads      */
69 	u32 nr_threads;		/* number of threads               */
70 	u32 avenrun[3];		/* average nr. of running processes during */
71 				/* the last 1, 5 and 15 minutes */
72 
73 	/* New in 2.6 */
74 	u32 nr_iowait;		/* number of blocked threads
75 				   (waiting for I/O)               */
76 
77 	/* per cpu data */
78 	struct appldata_os_per_cpu os_cpu[];
79 } __attribute__((packed));
80 
81 static struct appldata_os_data *appldata_os_data;
82 
83 static struct appldata_ops ops = {
84 	.name	   = "os",
85 	.record_nr = APPLDATA_RECORD_OS_ID,
86 	.owner	   = THIS_MODULE,
87 	.mod_lvl   = {0xF0, 0xF1},		/* EBCDIC "01" */
88 };
89 
90 
91 /*
92  * appldata_get_os_data()
93  *
94  * gather OS data
95  */
96 static void appldata_get_os_data(void *data)
97 {
98 	int i, j, rc;
99 	struct appldata_os_data *os_data;
100 	unsigned int new_size;
101 
102 	os_data = data;
103 	os_data->sync_count_1++;
104 
105 	os_data->nr_threads = nr_threads;
106 	os_data->nr_running = nr_running();
107 	os_data->nr_iowait  = nr_iowait();
108 	os_data->avenrun[0] = avenrun[0] + (FIXED_1/200);
109 	os_data->avenrun[1] = avenrun[1] + (FIXED_1/200);
110 	os_data->avenrun[2] = avenrun[2] + (FIXED_1/200);
111 
112 	j = 0;
113 	for_each_online_cpu(i) {
114 		os_data->os_cpu[j].per_cpu_user =
115 			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_USER]);
116 		os_data->os_cpu[j].per_cpu_nice =
117 			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_NICE]);
118 		os_data->os_cpu[j].per_cpu_system =
119 			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_SYSTEM]);
120 		os_data->os_cpu[j].per_cpu_idle =
121 			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_IDLE]);
122 		os_data->os_cpu[j].per_cpu_irq =
123 			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_IRQ]);
124 		os_data->os_cpu[j].per_cpu_softirq =
125 			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_SOFTIRQ]);
126 		os_data->os_cpu[j].per_cpu_iowait =
127 			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_IOWAIT]);
128 		os_data->os_cpu[j].per_cpu_steal =
129 			nsecs_to_jiffies(kcpustat_cpu(i).cpustat[CPUTIME_STEAL]);
130 		os_data->os_cpu[j].cpu_id = i;
131 		j++;
132 	}
133 
134 	os_data->nr_cpus = j;
135 
136 	new_size = sizeof(struct appldata_os_data) +
137 		   (os_data->nr_cpus * sizeof(struct appldata_os_per_cpu));
138 	if (ops.size != new_size) {
139 		if (ops.active) {
140 			rc = appldata_diag(APPLDATA_RECORD_OS_ID,
141 					   APPLDATA_START_INTERVAL_REC,
142 					   (unsigned long) ops.data, new_size,
143 					   ops.mod_lvl);
144 			if (rc != 0)
145 				pr_err("Starting a new OS data collection "
146 				       "failed with rc=%d\n", rc);
147 
148 			rc = appldata_diag(APPLDATA_RECORD_OS_ID,
149 					   APPLDATA_STOP_REC,
150 					   (unsigned long) ops.data, ops.size,
151 					   ops.mod_lvl);
152 			if (rc != 0)
153 				pr_err("Stopping a faulty OS data "
154 				       "collection failed with rc=%d\n", rc);
155 		}
156 		ops.size = new_size;
157 	}
158 	os_data->timestamp = get_tod_clock();
159 	os_data->sync_count_2++;
160 }
161 
162 
163 /*
164  * appldata_os_init()
165  *
166  * init data, register ops
167  */
168 static int __init appldata_os_init(void)
169 {
170 	int rc, max_size;
171 
172 	max_size = sizeof(struct appldata_os_data) +
173 		   (num_possible_cpus() * sizeof(struct appldata_os_per_cpu));
174 	if (max_size > APPLDATA_MAX_REC_SIZE) {
175 		pr_err("Maximum OS record size %i exceeds the maximum "
176 		       "record size %i\n", max_size, APPLDATA_MAX_REC_SIZE);
177 		rc = -ENOMEM;
178 		goto out;
179 	}
180 
181 	appldata_os_data = kzalloc(max_size, GFP_KERNEL | GFP_DMA);
182 	if (appldata_os_data == NULL) {
183 		rc = -ENOMEM;
184 		goto out;
185 	}
186 
187 	appldata_os_data->per_cpu_size = sizeof(struct appldata_os_per_cpu);
188 	appldata_os_data->cpu_offset   = offsetof(struct appldata_os_data,
189 							os_cpu);
190 
191 	ops.data = appldata_os_data;
192 	ops.callback  = &appldata_get_os_data;
193 	rc = appldata_register_ops(&ops);
194 	if (rc != 0)
195 		kfree(appldata_os_data);
196 out:
197 	return rc;
198 }
199 
200 /*
201  * appldata_os_exit()
202  *
203  * unregister ops
204  */
205 static void __exit appldata_os_exit(void)
206 {
207 	appldata_unregister_ops(&ops);
208 	kfree(appldata_os_data);
209 }
210 
211 
212 module_init(appldata_os_init);
213 module_exit(appldata_os_exit);
214 
215 MODULE_LICENSE("GPL");
216 MODULE_AUTHOR("Gerald Schaefer");
217 MODULE_DESCRIPTION("Linux-VM Monitor Stream, OS statistics");
218