1 /*
2  * arch/s390/appldata/appldata_base.c
3  *
4  * Base infrastructure for Linux-z/VM Monitor Stream, Stage 1.
5  * Exports appldata_register_ops() and appldata_unregister_ops() for the
6  * data gathering modules.
7  *
8  * Copyright IBM Corp. 2003, 2008
9  *
10  * Author: Gerald Schaefer <gerald.schaefer@de.ibm.com>
11  */
12 
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/slab.h>
16 #include <linux/errno.h>
17 #include <linux/interrupt.h>
18 #include <linux/proc_fs.h>
19 #include <linux/mm.h>
20 #include <linux/swap.h>
21 #include <linux/pagemap.h>
22 #include <linux/sysctl.h>
23 #include <linux/notifier.h>
24 #include <linux/cpu.h>
25 #include <linux/workqueue.h>
26 #include <asm/appldata.h>
27 #include <asm/timer.h>
28 #include <asm/uaccess.h>
29 #include <asm/io.h>
30 #include <asm/smp.h>
31 
32 #include "appldata.h"
33 
34 
35 #define MY_PRINT_NAME	"appldata"		/* for debug messages, etc. */
36 #define APPLDATA_CPU_INTERVAL	10000		/* default (CPU) time for
37 						   sampling interval in
38 						   milliseconds */
39 
40 #define TOD_MICRO	0x01000			/* nr. of TOD clock units
41 						   for 1 microsecond */
42 /*
43  * /proc entries (sysctl)
44  */
45 static const char appldata_proc_name[APPLDATA_PROC_NAME_LENGTH] = "appldata";
46 static int appldata_timer_handler(ctl_table *ctl, int write, struct file *filp,
47 				  void __user *buffer, size_t *lenp, loff_t *ppos);
48 static int appldata_interval_handler(ctl_table *ctl, int write,
49 					 struct file *filp,
50 					 void __user *buffer,
51 					 size_t *lenp, loff_t *ppos);
52 
53 static struct ctl_table_header *appldata_sysctl_header;
54 static struct ctl_table appldata_table[] = {
55 	{
56 		.procname	= "timer",
57 		.mode		= S_IRUGO | S_IWUSR,
58 		.proc_handler	= &appldata_timer_handler,
59 	},
60 	{
61 		.procname	= "interval",
62 		.mode		= S_IRUGO | S_IWUSR,
63 		.proc_handler	= &appldata_interval_handler,
64 	},
65 	{ },
66 };
67 
68 static struct ctl_table appldata_dir_table[] = {
69 	{
70 		.procname	= appldata_proc_name,
71 		.maxlen		= 0,
72 		.mode		= S_IRUGO | S_IXUGO,
73 		.child		= appldata_table,
74 	},
75 	{ },
76 };
77 
78 /*
79  * Timer
80  */
81 static DEFINE_PER_CPU(struct vtimer_list, appldata_timer);
82 static atomic_t appldata_expire_count = ATOMIC_INIT(0);
83 
84 static DEFINE_SPINLOCK(appldata_timer_lock);
85 static int appldata_interval = APPLDATA_CPU_INTERVAL;
86 static int appldata_timer_active;
87 
88 /*
89  * Work queue
90  */
91 static struct workqueue_struct *appldata_wq;
92 static void appldata_work_fn(struct work_struct *work);
93 static DECLARE_WORK(appldata_work, appldata_work_fn);
94 
95 
96 /*
97  * Ops list
98  */
99 static DEFINE_SPINLOCK(appldata_ops_lock);
100 static LIST_HEAD(appldata_ops_list);
101 
102 
103 /*************************** timer, work, DIAG *******************************/
104 /*
105  * appldata_timer_function()
106  *
107  * schedule work and reschedule timer
108  */
109 static void appldata_timer_function(unsigned long data)
110 {
111 	if (atomic_dec_and_test(&appldata_expire_count)) {
112 		atomic_set(&appldata_expire_count, num_online_cpus());
113 		queue_work(appldata_wq, (struct work_struct *) data);
114 	}
115 }
116 
117 /*
118  * appldata_work_fn()
119  *
120  * call data gathering function for each (active) module
121  */
122 static void appldata_work_fn(struct work_struct *work)
123 {
124 	struct list_head *lh;
125 	struct appldata_ops *ops;
126 	int i;
127 
128 	i = 0;
129 	get_online_cpus();
130 	spin_lock(&appldata_ops_lock);
131 	list_for_each(lh, &appldata_ops_list) {
132 		ops = list_entry(lh, struct appldata_ops, list);
133 		if (ops->active == 1) {
134 			ops->callback(ops->data);
135 		}
136 	}
137 	spin_unlock(&appldata_ops_lock);
138 	put_online_cpus();
139 }
140 
141 /*
142  * appldata_diag()
143  *
144  * prepare parameter list, issue DIAG 0xDC
145  */
146 int appldata_diag(char record_nr, u16 function, unsigned long buffer,
147 			u16 length, char *mod_lvl)
148 {
149 	struct appldata_product_id id = {
150 		.prod_nr    = {0xD3, 0xC9, 0xD5, 0xE4,
151 			       0xE7, 0xD2, 0xD9},	/* "LINUXKR" */
152 		.prod_fn    = 0xD5D3,			/* "NL" */
153 		.version_nr = 0xF2F6,			/* "26" */
154 		.release_nr = 0xF0F1,			/* "01" */
155 	};
156 
157 	id.record_nr = record_nr;
158 	id.mod_lvl = (mod_lvl[0]) << 8 | mod_lvl[1];
159 	return appldata_asm(&id, function, (void *) buffer, length);
160 }
161 /************************ timer, work, DIAG <END> ****************************/
162 
163 
164 /****************************** /proc stuff **********************************/
165 
166 /*
167  * appldata_mod_vtimer_wrap()
168  *
169  * wrapper function for mod_virt_timer(), because smp_call_function_single()
170  * accepts only one parameter.
171  */
172 static void __appldata_mod_vtimer_wrap(void *p) {
173 	struct {
174 		struct vtimer_list *timer;
175 		u64    expires;
176 	} *args = p;
177 	mod_virt_timer(args->timer, args->expires);
178 }
179 
180 #define APPLDATA_ADD_TIMER	0
181 #define APPLDATA_DEL_TIMER	1
182 #define APPLDATA_MOD_TIMER	2
183 
184 /*
185  * __appldata_vtimer_setup()
186  *
187  * Add, delete or modify virtual timers on all online cpus.
188  * The caller needs to get the appldata_timer_lock spinlock.
189  */
190 static void
191 __appldata_vtimer_setup(int cmd)
192 {
193 	u64 per_cpu_interval;
194 	int i;
195 
196 	switch (cmd) {
197 	case APPLDATA_ADD_TIMER:
198 		if (appldata_timer_active)
199 			break;
200 		per_cpu_interval = (u64) (appldata_interval*1000 /
201 					  num_online_cpus()) * TOD_MICRO;
202 		for_each_online_cpu(i) {
203 			per_cpu(appldata_timer, i).expires = per_cpu_interval;
204 			smp_call_function_single(i, add_virt_timer_periodic,
205 						 &per_cpu(appldata_timer, i),
206 						 1);
207 		}
208 		appldata_timer_active = 1;
209 		break;
210 	case APPLDATA_DEL_TIMER:
211 		for_each_online_cpu(i)
212 			del_virt_timer(&per_cpu(appldata_timer, i));
213 		if (!appldata_timer_active)
214 			break;
215 		appldata_timer_active = 0;
216 		atomic_set(&appldata_expire_count, num_online_cpus());
217 		break;
218 	case APPLDATA_MOD_TIMER:
219 		per_cpu_interval = (u64) (appldata_interval*1000 /
220 					  num_online_cpus()) * TOD_MICRO;
221 		if (!appldata_timer_active)
222 			break;
223 		for_each_online_cpu(i) {
224 			struct {
225 				struct vtimer_list *timer;
226 				u64    expires;
227 			} args;
228 			args.timer = &per_cpu(appldata_timer, i);
229 			args.expires = per_cpu_interval;
230 			smp_call_function_single(i, __appldata_mod_vtimer_wrap,
231 						 &args, 1);
232 		}
233 	}
234 }
235 
236 /*
237  * appldata_timer_handler()
238  *
239  * Start/Stop timer, show status of timer (0 = not active, 1 = active)
240  */
241 static int
242 appldata_timer_handler(ctl_table *ctl, int write, struct file *filp,
243 			   void __user *buffer, size_t *lenp, loff_t *ppos)
244 {
245 	int len;
246 	char buf[2];
247 
248 	if (!*lenp || *ppos) {
249 		*lenp = 0;
250 		return 0;
251 	}
252 	if (!write) {
253 		len = sprintf(buf, appldata_timer_active ? "1\n" : "0\n");
254 		if (len > *lenp)
255 			len = *lenp;
256 		if (copy_to_user(buffer, buf, len))
257 			return -EFAULT;
258 		goto out;
259 	}
260 	len = *lenp;
261 	if (copy_from_user(buf, buffer, len > sizeof(buf) ? sizeof(buf) : len))
262 		return -EFAULT;
263 	get_online_cpus();
264 	spin_lock(&appldata_timer_lock);
265 	if (buf[0] == '1')
266 		__appldata_vtimer_setup(APPLDATA_ADD_TIMER);
267 	else if (buf[0] == '0')
268 		__appldata_vtimer_setup(APPLDATA_DEL_TIMER);
269 	spin_unlock(&appldata_timer_lock);
270 	put_online_cpus();
271 out:
272 	*lenp = len;
273 	*ppos += len;
274 	return 0;
275 }
276 
277 /*
278  * appldata_interval_handler()
279  *
280  * Set (CPU) timer interval for collection of data (in milliseconds), show
281  * current timer interval.
282  */
283 static int
284 appldata_interval_handler(ctl_table *ctl, int write, struct file *filp,
285 			   void __user *buffer, size_t *lenp, loff_t *ppos)
286 {
287 	int len, interval;
288 	char buf[16];
289 
290 	if (!*lenp || *ppos) {
291 		*lenp = 0;
292 		return 0;
293 	}
294 	if (!write) {
295 		len = sprintf(buf, "%i\n", appldata_interval);
296 		if (len > *lenp)
297 			len = *lenp;
298 		if (copy_to_user(buffer, buf, len))
299 			return -EFAULT;
300 		goto out;
301 	}
302 	len = *lenp;
303 	if (copy_from_user(buf, buffer, len > sizeof(buf) ? sizeof(buf) : len)) {
304 		return -EFAULT;
305 	}
306 	interval = 0;
307 	sscanf(buf, "%i", &interval);
308 	if (interval <= 0)
309 		return -EINVAL;
310 
311 	get_online_cpus();
312 	spin_lock(&appldata_timer_lock);
313 	appldata_interval = interval;
314 	__appldata_vtimer_setup(APPLDATA_MOD_TIMER);
315 	spin_unlock(&appldata_timer_lock);
316 	put_online_cpus();
317 out:
318 	*lenp = len;
319 	*ppos += len;
320 	return 0;
321 }
322 
323 /*
324  * appldata_generic_handler()
325  *
326  * Generic start/stop monitoring and DIAG, show status of
327  * monitoring (0 = not in process, 1 = in process)
328  */
329 static int
330 appldata_generic_handler(ctl_table *ctl, int write, struct file *filp,
331 			   void __user *buffer, size_t *lenp, loff_t *ppos)
332 {
333 	struct appldata_ops *ops = NULL, *tmp_ops;
334 	int rc, len, found;
335 	char buf[2];
336 	struct list_head *lh;
337 
338 	found = 0;
339 	spin_lock(&appldata_ops_lock);
340 	list_for_each(lh, &appldata_ops_list) {
341 		tmp_ops = list_entry(lh, struct appldata_ops, list);
342 		if (&tmp_ops->ctl_table[2] == ctl) {
343 			found = 1;
344 		}
345 	}
346 	if (!found) {
347 		spin_unlock(&appldata_ops_lock);
348 		return -ENODEV;
349 	}
350 	ops = ctl->data;
351 	if (!try_module_get(ops->owner)) {	// protect this function
352 		spin_unlock(&appldata_ops_lock);
353 		return -ENODEV;
354 	}
355 	spin_unlock(&appldata_ops_lock);
356 
357 	if (!*lenp || *ppos) {
358 		*lenp = 0;
359 		module_put(ops->owner);
360 		return 0;
361 	}
362 	if (!write) {
363 		len = sprintf(buf, ops->active ? "1\n" : "0\n");
364 		if (len > *lenp)
365 			len = *lenp;
366 		if (copy_to_user(buffer, buf, len)) {
367 			module_put(ops->owner);
368 			return -EFAULT;
369 		}
370 		goto out;
371 	}
372 	len = *lenp;
373 	if (copy_from_user(buf, buffer,
374 			   len > sizeof(buf) ? sizeof(buf) : len)) {
375 		module_put(ops->owner);
376 		return -EFAULT;
377 	}
378 
379 	spin_lock(&appldata_ops_lock);
380 	if ((buf[0] == '1') && (ops->active == 0)) {
381 		// protect work queue callback
382 		if (!try_module_get(ops->owner)) {
383 			spin_unlock(&appldata_ops_lock);
384 			module_put(ops->owner);
385 			return -ENODEV;
386 		}
387 		ops->callback(ops->data);	// init record
388 		rc = appldata_diag(ops->record_nr,
389 					APPLDATA_START_INTERVAL_REC,
390 					(unsigned long) ops->data, ops->size,
391 					ops->mod_lvl);
392 		if (rc != 0) {
393 			P_ERROR("START DIAG 0xDC for %s failed, "
394 				"return code: %d\n", ops->name, rc);
395 			module_put(ops->owner);
396 		} else
397 			ops->active = 1;
398 	} else if ((buf[0] == '0') && (ops->active == 1)) {
399 		ops->active = 0;
400 		rc = appldata_diag(ops->record_nr, APPLDATA_STOP_REC,
401 				(unsigned long) ops->data, ops->size,
402 				ops->mod_lvl);
403 		if (rc != 0)
404 			P_ERROR("STOP DIAG 0xDC for %s failed, "
405 				"return code: %d\n", ops->name, rc);
406 		module_put(ops->owner);
407 	}
408 	spin_unlock(&appldata_ops_lock);
409 out:
410 	*lenp = len;
411 	*ppos += len;
412 	module_put(ops->owner);
413 	return 0;
414 }
415 
416 /*************************** /proc stuff <END> *******************************/
417 
418 
419 /************************* module-ops management *****************************/
420 /*
421  * appldata_register_ops()
422  *
423  * update ops list, register /proc/sys entries
424  */
425 int appldata_register_ops(struct appldata_ops *ops)
426 {
427 	if ((ops->size > APPLDATA_MAX_REC_SIZE) || (ops->size < 0))
428 		return -EINVAL;
429 
430 	ops->ctl_table = kzalloc(4 * sizeof(struct ctl_table), GFP_KERNEL);
431 	if (!ops->ctl_table)
432 		return -ENOMEM;
433 
434 	spin_lock(&appldata_ops_lock);
435 	list_add(&ops->list, &appldata_ops_list);
436 	spin_unlock(&appldata_ops_lock);
437 
438 	ops->ctl_table[0].procname = appldata_proc_name;
439 	ops->ctl_table[0].maxlen   = 0;
440 	ops->ctl_table[0].mode     = S_IRUGO | S_IXUGO;
441 	ops->ctl_table[0].child    = &ops->ctl_table[2];
442 
443 	ops->ctl_table[2].procname = ops->name;
444 	ops->ctl_table[2].mode     = S_IRUGO | S_IWUSR;
445 	ops->ctl_table[2].proc_handler = appldata_generic_handler;
446 	ops->ctl_table[2].data = ops;
447 
448 	ops->sysctl_header = register_sysctl_table(ops->ctl_table);
449 	if (!ops->sysctl_header)
450 		goto out;
451 	return 0;
452 out:
453 	spin_lock(&appldata_ops_lock);
454 	list_del(&ops->list);
455 	spin_unlock(&appldata_ops_lock);
456 	kfree(ops->ctl_table);
457 	return -ENOMEM;
458 }
459 
460 /*
461  * appldata_unregister_ops()
462  *
463  * update ops list, unregister /proc entries, stop DIAG if necessary
464  */
465 void appldata_unregister_ops(struct appldata_ops *ops)
466 {
467 	spin_lock(&appldata_ops_lock);
468 	list_del(&ops->list);
469 	spin_unlock(&appldata_ops_lock);
470 	unregister_sysctl_table(ops->sysctl_header);
471 	kfree(ops->ctl_table);
472 }
473 /********************** module-ops management <END> **************************/
474 
475 
476 /******************************* init / exit *********************************/
477 
478 static void __cpuinit appldata_online_cpu(int cpu)
479 {
480 	init_virt_timer(&per_cpu(appldata_timer, cpu));
481 	per_cpu(appldata_timer, cpu).function = appldata_timer_function;
482 	per_cpu(appldata_timer, cpu).data = (unsigned long)
483 		&appldata_work;
484 	atomic_inc(&appldata_expire_count);
485 	spin_lock(&appldata_timer_lock);
486 	__appldata_vtimer_setup(APPLDATA_MOD_TIMER);
487 	spin_unlock(&appldata_timer_lock);
488 }
489 
490 static void __cpuinit appldata_offline_cpu(int cpu)
491 {
492 	del_virt_timer(&per_cpu(appldata_timer, cpu));
493 	if (atomic_dec_and_test(&appldata_expire_count)) {
494 		atomic_set(&appldata_expire_count, num_online_cpus());
495 		queue_work(appldata_wq, &appldata_work);
496 	}
497 	spin_lock(&appldata_timer_lock);
498 	__appldata_vtimer_setup(APPLDATA_MOD_TIMER);
499 	spin_unlock(&appldata_timer_lock);
500 }
501 
502 static int __cpuinit appldata_cpu_notify(struct notifier_block *self,
503 					 unsigned long action,
504 					 void *hcpu)
505 {
506 	switch (action) {
507 	case CPU_ONLINE:
508 	case CPU_ONLINE_FROZEN:
509 		appldata_online_cpu((long) hcpu);
510 		break;
511 	case CPU_DEAD:
512 	case CPU_DEAD_FROZEN:
513 		appldata_offline_cpu((long) hcpu);
514 		break;
515 	default:
516 		break;
517 	}
518 	return NOTIFY_OK;
519 }
520 
521 static struct notifier_block __cpuinitdata appldata_nb = {
522 	.notifier_call = appldata_cpu_notify,
523 };
524 
525 /*
526  * appldata_init()
527  *
528  * init timer, register /proc entries
529  */
530 static int __init appldata_init(void)
531 {
532 	int i;
533 
534 	appldata_wq = create_singlethread_workqueue("appldata");
535 	if (!appldata_wq)
536 		return -ENOMEM;
537 
538 	get_online_cpus();
539 	for_each_online_cpu(i)
540 		appldata_online_cpu(i);
541 	put_online_cpus();
542 
543 	/* Register cpu hotplug notifier */
544 	register_hotcpu_notifier(&appldata_nb);
545 
546 	appldata_sysctl_header = register_sysctl_table(appldata_dir_table);
547 	return 0;
548 }
549 
550 __initcall(appldata_init);
551 
552 /**************************** init / exit <END> ******************************/
553 
554 EXPORT_SYMBOL_GPL(appldata_register_ops);
555 EXPORT_SYMBOL_GPL(appldata_unregister_ops);
556 EXPORT_SYMBOL_GPL(appldata_diag);
557 
558 #ifdef CONFIG_SWAP
559 EXPORT_SYMBOL_GPL(si_swapinfo);
560 #endif
561 EXPORT_SYMBOL_GPL(nr_threads);
562 EXPORT_SYMBOL_GPL(nr_running);
563 EXPORT_SYMBOL_GPL(nr_iowait);
564