xref: /linux/arch/s390/appldata/appldata_base.c (revision 8e07e0e3964ca4e23ce7b68e2096fe660a888942)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Base infrastructure for Linux-z/VM Monitor Stream, Stage 1.
4  * Exports appldata_register_ops() and appldata_unregister_ops() for the
5  * data gathering modules.
6  *
7  * Copyright IBM Corp. 2003, 2009
8  *
9  * Author: Gerald Schaefer <gerald.schaefer@de.ibm.com>
10  */
11 
12 #define KMSG_COMPONENT	"appldata"
13 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
14 
15 #include <linux/module.h>
16 #include <linux/sched/stat.h>
17 #include <linux/init.h>
18 #include <linux/slab.h>
19 #include <linux/errno.h>
20 #include <linux/interrupt.h>
21 #include <linux/proc_fs.h>
22 #include <linux/mm.h>
23 #include <linux/swap.h>
24 #include <linux/pagemap.h>
25 #include <linux/sysctl.h>
26 #include <linux/notifier.h>
27 #include <linux/cpu.h>
28 #include <linux/workqueue.h>
29 #include <linux/uaccess.h>
30 #include <linux/io.h>
31 #include <asm/appldata.h>
32 #include <asm/vtimer.h>
33 #include <asm/smp.h>
34 
35 #include "appldata.h"
36 
37 
38 #define APPLDATA_CPU_INTERVAL	10000		/* default (CPU) time for
39 						   sampling interval in
40 						   milliseconds */
41 
42 #define TOD_MICRO	0x01000			/* nr. of TOD clock units
43 						   for 1 microsecond */
44 
45 /*
46  * /proc entries (sysctl)
47  */
48 static const char appldata_proc_name[APPLDATA_PROC_NAME_LENGTH] = "appldata";
49 static int appldata_timer_handler(struct ctl_table *ctl, int write,
50 				  void *buffer, size_t *lenp, loff_t *ppos);
51 static int appldata_interval_handler(struct ctl_table *ctl, int write,
52 				     void *buffer, size_t *lenp, loff_t *ppos);
53 
54 static struct ctl_table_header *appldata_sysctl_header;
55 static struct ctl_table appldata_table[] = {
56 	{
57 		.procname	= "timer",
58 		.mode		= S_IRUGO | S_IWUSR,
59 		.proc_handler	= appldata_timer_handler,
60 	},
61 	{
62 		.procname	= "interval",
63 		.mode		= S_IRUGO | S_IWUSR,
64 		.proc_handler	= appldata_interval_handler,
65 	},
66 };
67 
68 /*
69  * Timer
70  */
71 static struct vtimer_list appldata_timer;
72 
73 static DEFINE_SPINLOCK(appldata_timer_lock);
74 static int appldata_interval = APPLDATA_CPU_INTERVAL;
75 static int appldata_timer_active;
76 
77 /*
78  * Work queue
79  */
80 static struct workqueue_struct *appldata_wq;
81 static void appldata_work_fn(struct work_struct *work);
82 static DECLARE_WORK(appldata_work, appldata_work_fn);
83 
84 
85 /*
86  * Ops list
87  */
88 static DEFINE_MUTEX(appldata_ops_mutex);
89 static LIST_HEAD(appldata_ops_list);
90 
91 
92 /*************************** timer, work, DIAG *******************************/
93 /*
94  * appldata_timer_function()
95  *
96  * schedule work and reschedule timer
97  */
98 static void appldata_timer_function(unsigned long data)
99 {
100 	queue_work(appldata_wq, (struct work_struct *) data);
101 }
102 
103 /*
104  * appldata_work_fn()
105  *
106  * call data gathering function for each (active) module
107  */
108 static void appldata_work_fn(struct work_struct *work)
109 {
110 	struct list_head *lh;
111 	struct appldata_ops *ops;
112 
113 	mutex_lock(&appldata_ops_mutex);
114 	list_for_each(lh, &appldata_ops_list) {
115 		ops = list_entry(lh, struct appldata_ops, list);
116 		if (ops->active == 1) {
117 			ops->callback(ops->data);
118 		}
119 	}
120 	mutex_unlock(&appldata_ops_mutex);
121 }
122 
123 static struct appldata_product_id appldata_id = {
124 	.prod_nr    = {0xD3, 0xC9, 0xD5, 0xE4,
125 		       0xE7, 0xD2, 0xD9},	/* "LINUXKR" */
126 	.prod_fn    = 0xD5D3,			/* "NL" */
127 	.version_nr = 0xF2F6,			/* "26" */
128 	.release_nr = 0xF0F1,			/* "01" */
129 };
130 
131 /*
132  * appldata_diag()
133  *
134  * prepare parameter list, issue DIAG 0xDC
135  */
136 int appldata_diag(char record_nr, u16 function, unsigned long buffer,
137 			u16 length, char *mod_lvl)
138 {
139 	struct appldata_parameter_list *parm_list;
140 	struct appldata_product_id *id;
141 	int rc;
142 
143 	parm_list = kmalloc(sizeof(*parm_list), GFP_KERNEL);
144 	id = kmemdup(&appldata_id, sizeof(appldata_id), GFP_KERNEL);
145 	rc = -ENOMEM;
146 	if (parm_list && id) {
147 		id->record_nr = record_nr;
148 		id->mod_lvl = (mod_lvl[0]) << 8 | mod_lvl[1];
149 		rc = appldata_asm(parm_list, id, function,
150 				  (void *) buffer, length);
151 	}
152 	kfree(id);
153 	kfree(parm_list);
154 	return rc;
155 }
156 /************************ timer, work, DIAG <END> ****************************/
157 
158 
159 /****************************** /proc stuff **********************************/
160 
161 #define APPLDATA_ADD_TIMER	0
162 #define APPLDATA_DEL_TIMER	1
163 #define APPLDATA_MOD_TIMER	2
164 
165 /*
166  * __appldata_vtimer_setup()
167  *
168  * Add, delete or modify virtual timers on all online cpus.
169  * The caller needs to get the appldata_timer_lock spinlock.
170  */
171 static void __appldata_vtimer_setup(int cmd)
172 {
173 	u64 timer_interval = (u64) appldata_interval * 1000 * TOD_MICRO;
174 
175 	switch (cmd) {
176 	case APPLDATA_ADD_TIMER:
177 		if (appldata_timer_active)
178 			break;
179 		appldata_timer.expires = timer_interval;
180 		add_virt_timer_periodic(&appldata_timer);
181 		appldata_timer_active = 1;
182 		break;
183 	case APPLDATA_DEL_TIMER:
184 		del_virt_timer(&appldata_timer);
185 		if (!appldata_timer_active)
186 			break;
187 		appldata_timer_active = 0;
188 		break;
189 	case APPLDATA_MOD_TIMER:
190 		if (!appldata_timer_active)
191 			break;
192 		mod_virt_timer_periodic(&appldata_timer, timer_interval);
193 	}
194 }
195 
196 /*
197  * appldata_timer_handler()
198  *
199  * Start/Stop timer, show status of timer (0 = not active, 1 = active)
200  */
201 static int
202 appldata_timer_handler(struct ctl_table *ctl, int write,
203 			   void *buffer, size_t *lenp, loff_t *ppos)
204 {
205 	int timer_active = appldata_timer_active;
206 	int rc;
207 	struct ctl_table ctl_entry = {
208 		.procname	= ctl->procname,
209 		.data		= &timer_active,
210 		.maxlen		= sizeof(int),
211 		.extra1		= SYSCTL_ZERO,
212 		.extra2		= SYSCTL_ONE,
213 	};
214 
215 	rc = proc_douintvec_minmax(&ctl_entry, write, buffer, lenp, ppos);
216 	if (rc < 0 || !write)
217 		return rc;
218 
219 	spin_lock(&appldata_timer_lock);
220 	if (timer_active)
221 		__appldata_vtimer_setup(APPLDATA_ADD_TIMER);
222 	else
223 		__appldata_vtimer_setup(APPLDATA_DEL_TIMER);
224 	spin_unlock(&appldata_timer_lock);
225 	return 0;
226 }
227 
228 /*
229  * appldata_interval_handler()
230  *
231  * Set (CPU) timer interval for collection of data (in milliseconds), show
232  * current timer interval.
233  */
234 static int
235 appldata_interval_handler(struct ctl_table *ctl, int write,
236 			   void *buffer, size_t *lenp, loff_t *ppos)
237 {
238 	int interval = appldata_interval;
239 	int rc;
240 	struct ctl_table ctl_entry = {
241 		.procname	= ctl->procname,
242 		.data		= &interval,
243 		.maxlen		= sizeof(int),
244 		.extra1		= SYSCTL_ONE,
245 	};
246 
247 	rc = proc_dointvec_minmax(&ctl_entry, write, buffer, lenp, ppos);
248 	if (rc < 0 || !write)
249 		return rc;
250 
251 	spin_lock(&appldata_timer_lock);
252 	appldata_interval = interval;
253 	__appldata_vtimer_setup(APPLDATA_MOD_TIMER);
254 	spin_unlock(&appldata_timer_lock);
255 	return 0;
256 }
257 
258 /*
259  * appldata_generic_handler()
260  *
261  * Generic start/stop monitoring and DIAG, show status of
262  * monitoring (0 = not in process, 1 = in process)
263  */
264 static int
265 appldata_generic_handler(struct ctl_table *ctl, int write,
266 			   void *buffer, size_t *lenp, loff_t *ppos)
267 {
268 	struct appldata_ops *ops = NULL, *tmp_ops;
269 	struct list_head *lh;
270 	int rc, found;
271 	int active;
272 	struct ctl_table ctl_entry = {
273 		.data		= &active,
274 		.maxlen		= sizeof(int),
275 		.extra1		= SYSCTL_ZERO,
276 		.extra2		= SYSCTL_ONE,
277 	};
278 
279 	found = 0;
280 	mutex_lock(&appldata_ops_mutex);
281 	list_for_each(lh, &appldata_ops_list) {
282 		tmp_ops = list_entry(lh, struct appldata_ops, list);
283 		if (&tmp_ops->ctl_table[0] == ctl) {
284 			found = 1;
285 		}
286 	}
287 	if (!found) {
288 		mutex_unlock(&appldata_ops_mutex);
289 		return -ENODEV;
290 	}
291 	ops = ctl->data;
292 	if (!try_module_get(ops->owner)) {	// protect this function
293 		mutex_unlock(&appldata_ops_mutex);
294 		return -ENODEV;
295 	}
296 	mutex_unlock(&appldata_ops_mutex);
297 
298 	active = ops->active;
299 	rc = proc_douintvec_minmax(&ctl_entry, write, buffer, lenp, ppos);
300 	if (rc < 0 || !write) {
301 		module_put(ops->owner);
302 		return rc;
303 	}
304 
305 	mutex_lock(&appldata_ops_mutex);
306 	if (active && (ops->active == 0)) {
307 		// protect work queue callback
308 		if (!try_module_get(ops->owner)) {
309 			mutex_unlock(&appldata_ops_mutex);
310 			module_put(ops->owner);
311 			return -ENODEV;
312 		}
313 		ops->callback(ops->data);	// init record
314 		rc = appldata_diag(ops->record_nr,
315 					APPLDATA_START_INTERVAL_REC,
316 					(unsigned long) ops->data, ops->size,
317 					ops->mod_lvl);
318 		if (rc != 0) {
319 			pr_err("Starting the data collection for %s "
320 			       "failed with rc=%d\n", ops->name, rc);
321 			module_put(ops->owner);
322 		} else
323 			ops->active = 1;
324 	} else if (!active && (ops->active == 1)) {
325 		ops->active = 0;
326 		rc = appldata_diag(ops->record_nr, APPLDATA_STOP_REC,
327 				(unsigned long) ops->data, ops->size,
328 				ops->mod_lvl);
329 		if (rc != 0)
330 			pr_err("Stopping the data collection for %s "
331 			       "failed with rc=%d\n", ops->name, rc);
332 		module_put(ops->owner);
333 	}
334 	mutex_unlock(&appldata_ops_mutex);
335 	module_put(ops->owner);
336 	return 0;
337 }
338 
339 /*************************** /proc stuff <END> *******************************/
340 
341 
342 /************************* module-ops management *****************************/
343 /*
344  * appldata_register_ops()
345  *
346  * update ops list, register /proc/sys entries
347  */
348 int appldata_register_ops(struct appldata_ops *ops)
349 {
350 	if (ops->size > APPLDATA_MAX_REC_SIZE)
351 		return -EINVAL;
352 
353 	ops->ctl_table = kcalloc(1, sizeof(struct ctl_table), GFP_KERNEL);
354 	if (!ops->ctl_table)
355 		return -ENOMEM;
356 
357 	mutex_lock(&appldata_ops_mutex);
358 	list_add(&ops->list, &appldata_ops_list);
359 	mutex_unlock(&appldata_ops_mutex);
360 
361 	ops->ctl_table[0].procname = ops->name;
362 	ops->ctl_table[0].mode = S_IRUGO | S_IWUSR;
363 	ops->ctl_table[0].proc_handler = appldata_generic_handler;
364 	ops->ctl_table[0].data = ops;
365 
366 	ops->sysctl_header = register_sysctl_sz(appldata_proc_name, ops->ctl_table, 1);
367 	if (!ops->sysctl_header)
368 		goto out;
369 	return 0;
370 out:
371 	mutex_lock(&appldata_ops_mutex);
372 	list_del(&ops->list);
373 	mutex_unlock(&appldata_ops_mutex);
374 	kfree(ops->ctl_table);
375 	return -ENOMEM;
376 }
377 
378 /*
379  * appldata_unregister_ops()
380  *
381  * update ops list, unregister /proc entries, stop DIAG if necessary
382  */
383 void appldata_unregister_ops(struct appldata_ops *ops)
384 {
385 	mutex_lock(&appldata_ops_mutex);
386 	list_del(&ops->list);
387 	mutex_unlock(&appldata_ops_mutex);
388 	unregister_sysctl_table(ops->sysctl_header);
389 	kfree(ops->ctl_table);
390 }
391 /********************** module-ops management <END> **************************/
392 
393 
394 /******************************* init / exit *********************************/
395 
396 /*
397  * appldata_init()
398  *
399  * init timer, register /proc entries
400  */
401 static int __init appldata_init(void)
402 {
403 	init_virt_timer(&appldata_timer);
404 	appldata_timer.function = appldata_timer_function;
405 	appldata_timer.data = (unsigned long) &appldata_work;
406 	appldata_wq = alloc_ordered_workqueue("appldata", 0);
407 	if (!appldata_wq)
408 		return -ENOMEM;
409 	appldata_sysctl_header = register_sysctl(appldata_proc_name, appldata_table);
410 	return 0;
411 }
412 
413 __initcall(appldata_init);
414 
415 /**************************** init / exit <END> ******************************/
416 
417 EXPORT_SYMBOL_GPL(appldata_register_ops);
418 EXPORT_SYMBOL_GPL(appldata_unregister_ops);
419 EXPORT_SYMBOL_GPL(appldata_diag);
420 
421 #ifdef CONFIG_SWAP
422 EXPORT_SYMBOL_GPL(si_swapinfo);
423 #endif
424 EXPORT_SYMBOL_GPL(nr_threads);
425 EXPORT_SYMBOL_GPL(nr_running);
426 EXPORT_SYMBOL_GPL(nr_iowait);
427