aboutsummaryrefslogtreecommitdiff
path: root/arch/s390/appldata/appldata_base.c
blob: 6a4b5f9715c902260cb7a2ea9e9e2f9e6be047e4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
/*
 * arch/s390/appldata/appldata_base.c
 *
 * Base infrastructure for Linux-z/VM Monitor Stream, Stage 1.
 * Exports appldata_register_ops() and appldata_unregister_ops() for the
 * data gathering modules.
 *
 * Copyright (C) 2003,2006 IBM Corporation, IBM Deutschland Entwicklung GmbH.
 *
 * Author: Gerald Schaefer <gerald.schaefer@de.ibm.com>
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/smp.h>
#include <linux/interrupt.h>
#include <linux/proc_fs.h>
#include <linux/page-flags.h>
#include <linux/swap.h>
#include <linux/pagemap.h>
#include <linux/sysctl.h>
#include <asm/timer.h>
//#include <linux/kernel_stat.h>
#include <linux/notifier.h>
#include <linux/cpu.h>
#include <linux/workqueue.h>

#include "appldata.h"


#define MY_PRINT_NAME	"appldata"		/* for debug messages, etc. */
#define APPLDATA_CPU_INTERVAL	10000		/* default (CPU) time for
						   sampling interval in
						   milliseconds */

#define TOD_MICRO	0x01000			/* nr. of TOD clock units
						   for 1 microsecond */

/*
 * Parameter list for DIAGNOSE X'DC'
 */
#ifndef CONFIG_64BIT
struct appldata_parameter_list {
	u16 diag;		/* The DIAGNOSE code X'00DC'          */
	u8  function;		/* The function code for the DIAGNOSE */
	u8  parlist_length;	/* Length of the parameter list       */
	u32 product_id_addr;	/* Address of the 16-byte product ID  */
	u16 reserved;
	u16 buffer_length;	/* Length of the application data buffer  */
	u32 buffer_addr;	/* Address of the application data buffer */
};
#else
struct appldata_parameter_list {
	u16 diag;
	u8  function;
	u8  parlist_length;
	u32 unused01;
	u16 reserved;
	u16 buffer_length;
	u32 unused02;
	u64 product_id_addr;
	u64 buffer_addr;
};
#endif /* CONFIG_64BIT */

/*
 * /proc entries (sysctl)
 */
static const char appldata_proc_name[APPLDATA_PROC_NAME_LENGTH] = "appldata";
static int appldata_timer_handler(ctl_table *ctl, int write, struct file *filp,
				  void __user *buffer, size_t *lenp, loff_t *ppos);
static int appldata_interval_handler(ctl_table *ctl, int write,
					 struct file *filp,
					 void __user *buffer,
					 size_t *lenp, loff_t *ppos);

static struct ctl_table_header *appldata_sysctl_header;
static struct ctl_table appldata_table[] = {
	{
		.ctl_name	= CTL_APPLDATA_TIMER,
		.procname	= "timer",
		.mode		= S_IRUGO | S_IWUSR,
		.proc_handler	= &appldata_timer_handler,
	},
	{
		.ctl_name	= CTL_APPLDATA_INTERVAL,
		.procname	= "interval",
		.mode		= S_IRUGO | S_IWUSR,
		.proc_handler	= &appldata_interval_handler,
	},
	{ .ctl_name = 0 }
};

static struct ctl_table appldata_dir_table[] = {
	{
		.ctl_name	= CTL_APPLDATA,
		.procname	= appldata_proc_name,
		.maxlen		= 0,
		.mode		= S_IRUGO | S_IXUGO,
		.child		= appldata_table,
	},
	{ .ctl_name = 0 }
};

/*
 * Timer
 */
DEFINE_PER_CPU(struct vtimer_list, appldata_timer);
static atomic_t appldata_expire_count = ATOMIC_INIT(0);

static DEFINE_SPINLOCK(appldata_timer_lock);
static int appldata_interval = APPLDATA_CPU_INTERVAL;
static int appldata_timer_active;

/*
 * Work queue
 */
static struct workqueue_struct *appldata_wq;
static void appldata_work_fn(void *data);
static DECLARE_WORK(appldata_work, appldata_work_fn, NULL);


/*
 * Ops list
 */
static DEFINE_SPINLOCK(appldata_ops_lock);
static LIST_HEAD(appldata_ops_list);


/*************************** timer, work, DIAG *******************************/
/*
 * appldata_timer_function()
 *
 * schedule work and reschedule timer
 */
static void appldata_timer_function(unsigned long data, struct pt_regs *regs)
{
	P_DEBUG("   -= Timer =-\n");
	P_DEBUG("CPU: %i, expire_count: %i\n", smp_processor_id(),
		atomic_read(&appldata_expire_count));
	if (atomic_dec_and_test(&appldata_expire_count)) {
		atomic_set(&appldata_expire_count, num_online_cpus());
		queue_work(appldata_wq, (struct work_struct *) data);
	}
}

/*
 * appldata_work_fn()
 *
 * call data gathering function for each (active) module
 */
static void appldata_work_fn(void *data)
{
	struct list_head *lh;
	struct appldata_ops *ops;
	int i;

	P_DEBUG("  -= Work Queue =-\n");
	i = 0;
	spin_lock(&appldata_ops_lock);
	list_for_each(lh, &appldata_ops_list) {
		ops = list_entry(lh, struct appldata_ops, list);
		P_DEBUG("list_for_each loop: %i) active = %u, name = %s\n",
			++i, ops->active, ops->name);
		if (ops->active == 1) {
			ops->callback(ops->data);
		}
	}
	spin_unlock(&appldata_ops_lock);
}

/*
 * appldata_diag()
 *
 * prepare parameter list, issue DIAG 0xDC
 */
int appldata_diag(char record_nr, u16 function, unsigned long buffer,
			u16 length, char *mod_lvl)
{
	unsigned long ry;
	struct appldata_product_id {
		char prod_nr[7];			/* product nr. */
		char prod_fn[2];			/* product function */
		char record_nr;				/* record nr. */
		char version_nr[2];			/* version */
		char release_nr[2];			/* release */
		char mod_lvl[2];			/* modification lvl. */
	} appldata_product_id = {
	/* all strings are EBCDIC, record_nr is byte */
		.prod_nr    = {0xD3, 0xC9, 0xD5, 0xE4,
				0xE7, 0xD2, 0xD9},	/* "LINUXKR" */
		.prod_fn    = {0xD5, 0xD3},		/* "NL" */
		.record_nr  = record_nr,
		.version_nr = {0xF2, 0xF6},		/* "26" */
		.release_nr = {0xF0, 0xF1},		/* "01" */
		.mod_lvl    = {mod_lvl[0], mod_lvl[1]},
	};
	struct appldata_parameter_list appldata_parameter_list = {
				.diag = 0xDC,
				.function = function,
				.parlist_length =
					sizeof(appldata_parameter_list),
				.buffer_length = length,
				.product_id_addr =
					(unsigned long) &appldata_product_id,
				.buffer_addr = virt_to_phys((void *) buffer)
	};

	if (!MACHINE_IS_VM)
		return -ENOSYS;
	ry = -1;
	asm volatile(
			"diag %1,%0,0xDC\n\t"
			: "=d" (ry)
			: "d" (&appldata_parameter_list),
			  "m" (appldata_parameter_list),
			  "m" (appldata_product_id)
			: "cc");
	return (int) ry;
}
/************************ timer, work, DIAG <END> ****************************/


/****************************** /proc stuff **********************************/

/*
 * appldata_mod_vtimer_wrap()
 *
 * wrapper function for mod_virt_timer(), because smp_call_function_on()
 * accepts only one parameter.
 */
static void __appldata_mod_vtimer_wrap(void *p) {
	struct {
		struct vtimer_list *timer;
		u64    expires;
	} *args = p;
	mod_virt_timer(args->timer, args->expires);
}

#define APPLDATA_ADD_TIMER	0
#define APPLDATA_DEL_TIMER	1
#define APPLDATA_MOD_TIMER	2

/*
 * __appldata_vtimer_setup()
 *
 * Add, delete or modify virtual timers on all online cpus.
 * The caller needs to get the appldata_timer_lock spinlock.
 */
static void
__appldata_vtimer_setup(int cmd)
{
	u64 per_cpu_interval;
	int i;

	switch (cmd) {
	case APPLDATA_ADD_TIMER:
		if (appldata_timer_active)
			break;
		per_cpu_interval = (u64) (appldata_interval*1000 /
					  num_online_cpus()) * TOD_MICRO;
		for_each_online_cpu(i) {
			per_cpu(appldata_timer, i).expires = per_cpu_interval;
			smp_call_function_on(add_virt_timer_periodic,
					     &per_cpu(appldata_timer, i),
					     0, 1, i);
		}
		appldata_timer_active = 1;
		P_INFO("Monitoring timer started.\n");
		break;
	case APPLDATA_DEL_TIMER:
		for_each_online_cpu(i)
			del_virt_timer(&per_cpu(appldata_timer, i));
		if (!appldata_timer_active)
			break;
		appldata_timer_active = 0;
		atomic_set(&appldata_expire_count, num_online_cpus());
		P_INFO("Monitoring timer stopped.\n");
		break;
	case APPLDATA_MOD_TIMER:
		per_cpu_interval = (u64) (appldata_interval*1000 /
					  num_online_cpus()) * TOD_MICRO;
		if (!appldata_timer_active)
			break;
		for_each_online_cpu(i) {
			struct {
				struct vtimer_list *timer;
				u64    expires;
			} args;
			args.timer = &per_cpu(appldata_timer, i);
			args.expires = per_cpu_interval;
			smp_call_function_on(__appldata_mod_vtimer_wrap,
					     &args, 0, 1, i);
		}
	}
}

/*
 * appldata_timer_handler()
 *
 * Start/Stop timer, show status of timer (0 = not active, 1 = active)
 */
static int
appldata_timer_handler(ctl_table *ctl, int write, struct file *filp,
			   void __user *buffer, size_t *lenp, loff_t *ppos)
{
	int len;
	char buf[2];

	if (!*lenp || *ppos) {
		*lenp = 0;
		return 0;
	}
	if (!write) {
		len = sprintf(buf, appldata_timer_active ? "1\n" : "0\n");
		if (len > *lenp)
			len = *lenp;
		if (copy_to_user(buffer, buf, len))
			return -EFAULT;
		goto out;
	}
	len = *lenp;
	if (copy_from_user(buf, buffer, len > sizeof(buf) ? sizeof(buf) : len))
		return -EFAULT;
	spin_lock(&appldata_timer_lock);
	if (buf[0] == '1')
		__appldata_vtimer_setup(APPLDATA_ADD_TIMER);
	else if (buf[0] == '0')
		__appldata_vtimer_setup(APPLDATA_DEL_TIMER);
	spin_unlock(&appldata_timer_lock);
out:
	*lenp = len;
	*ppos += len;
	return 0;
}

/*
 * appldata_interval_handler()
 *
 * Set (CPU) timer interval for collection of data (in milliseconds), show
 * current timer interval.
 */
static int
appldata_interval_handler(ctl_table *ctl, int write, struct file *filp,
			   void __user *buffer, size_t *lenp, loff_t *ppos)
{
	int len, interval;
	char buf[16];

	if (!*lenp || *ppos) {
		*lenp = 0;
		return 0;
	}
	if (!write) {
		len = sprintf(buf, "%i\n", appldata_interval);
		if (len > *lenp)
			len = *lenp;
		if (copy_to_user(buffer, buf, len))
			return -EFAULT;
		goto out;
	}
	len = *lenp;
	if (copy_from_user(buf, buffer, len > sizeof(buf) ? sizeof(buf) : len)) {
		return -EFAULT;
	}
	sscanf(buf, "%i", &interval);
	if (interval <= 0) {
		P_ERROR("Timer CPU interval has to be > 0!\n");
		return -EINVAL;
	}

	spin_lock(&appldata_timer_lock);
	appldata_interval = interval;
	__appldata_vtimer_setup(APPLDATA_MOD_TIMER);
	spin_unlock(&appldata_timer_lock);

	P_INFO("Monitoring CPU interval set to %u milliseconds.\n",
		 interval);
out:
	*lenp = len;
	*ppos += len;
	return 0;
}

/*
 * appldata_generic_handler()
 *
 * Generic start/stop monitoring and DIAG, show status of
 * monitoring (0 = not in process, 1 = in process)
 */
static int
appldata_generic_handler(ctl_table *ctl, int write, struct file *filp,
			   void __user *buffer, size_t *lenp, loff_t *ppos)
{
	struct appldata_ops *ops = NULL, *tmp_ops;
	int rc, len, found;
	char buf[2];
	struct list_head *lh;

	found = 0;
	spin_lock(&appldata_ops_lock);
	list_for_each(lh, &appldata_ops_list) {
		tmp_ops = list_entry(lh, struct appldata_ops, list);
		if (&tmp_ops->ctl_table[2] == ctl) {
			found = 1;
		}
	}
	if (!found) {
		spin_unlock(&appldata_ops_lock);
		return -ENODEV;
	}
	ops = ctl->data;
	if (!try_module_get(ops->owner)) {	// protect this function
		spin_unlock(&appldata_ops_lock);
		return -ENODEV;
	}
	spin_unlock(&appldata_ops_lock);

	if (!*lenp || *ppos) {
		*lenp = 0;
		module_put(ops->owner);
		return 0;
	}
	if (!write) {
		len = sprintf(buf, ops->active ? "1\n" : "0\n");
		if (len > *lenp)
			len = *lenp;
		if (copy_to_user(buffer, buf, len)) {
			module_put(ops->owner);
			return -EFAULT;
		}
		goto out;
	}
	len = *lenp;
	if (copy_from_user(buf, buffer,
			   len > sizeof(buf) ? sizeof(buf) : len)) {
		module_put(ops->owner);
		return -EFAULT;
	}

	spin_lock(&appldata_ops_lock);
	if ((buf[0] == '1') && (ops->active == 0)) {
		// protect work queue callback
		if (!try_module_get(ops->owner)) {
			spin_unlock(&appldata_ops_lock);
			module_put(ops->owner);
			return -ENODEV;
		}
		ops->callback(ops->data);	// init record
		rc = appldata_diag(ops->record_nr,
					APPLDATA_START_INTERVAL_REC,
					(unsigned long) ops->data, ops->size,
					ops->mod_lvl);
		if (rc != 0) {
			P_ERROR("START DIAG 0xDC for %s failed, "
				"return code: %d\n", ops->name, rc);
			module_put(ops->owner);
		} else {
			P_INFO("Monitoring %s data enabled, "
				"DIAG 0xDC started.\n", ops->name);
			ops->active = 1;
		}
	} else if ((buf[0] == '0') && (ops->active == 1)) {
		ops->active = 0;
		rc = appldata_diag(ops->record_nr, APPLDATA_STOP_REC,
				(unsigned long) ops->data, ops->size,
				ops->mod_lvl);
		if (rc != 0) {
			P_ERROR("STOP DIAG 0xDC for %s failed, "
				"return code: %d\n", ops->name, rc);
		} else {
			P_INFO("Monitoring %s data disabled, "
				"DIAG 0xDC stopped.\n", ops->name);
		}
		module_put(ops->owner);
	}
	spin_unlock(&appldata_ops_lock);
out:
	*lenp = len;
	*ppos += len;
	module_put(ops->owner);
	return 0;
}

/*************************** /proc stuff <END> *******************************/


/************************* module-ops management *****************************/
/*
 * appldata_register_ops()
 *
 * update ops list, register /proc/sys entries
 */
int appldata_register_ops(struct appldata_ops *ops)
{
	struct list_head *lh;
	struct appldata_ops *tmp_ops;
	int i;

	i = 0;

	if ((ops->size > APPLDATA_MAX_REC_SIZE) ||
		(ops->size < 0)){
		P_ERROR("Invalid size of %s record = %i, maximum = %i!\n",
			ops->name, ops->size, APPLDATA_MAX_REC_SIZE);
		return -ENOMEM;
	}
	if ((ops->ctl_nr == CTL_APPLDATA) ||
	    (ops->ctl_nr == CTL_APPLDATA_TIMER) ||
	    (ops->ctl_nr == CTL_APPLDATA_INTERVAL)) {
		P_ERROR("ctl_nr %i already in use!\n", ops->ctl_nr);
		return -EBUSY;
	}
	ops->ctl_table = kzalloc(4*sizeof(struct ctl_table), GFP_KERNEL);
	if (ops->ctl_table == NULL) {
		P_ERROR("Not enough memory for %s ctl_table!\n", ops->name);
		return -ENOMEM;
	}

	spin_lock(&appldata_ops_lock);
	list_for_each(lh, &appldata_ops_list) {
		tmp_ops = list_entry(lh, struct appldata_ops, list);
		P_DEBUG("register_ops loop: %i) name = %s, ctl = %i\n",
			++i, tmp_ops->name, tmp_ops->ctl_nr);
		P_DEBUG("Comparing %s (ctl %i) with %s (ctl %i)\n",
			tmp_ops->name, tmp_ops->ctl_nr, ops->name,
			ops->ctl_nr);
		if (strncmp(tmp_ops->name, ops->name,
				APPLDATA_PROC_NAME_LENGTH) == 0) {
			P_ERROR("Name \"%s\" already registered!\n", ops->name);
			kfree(ops->ctl_table);
			spin_unlock(&appldata_ops_lock);
			return -EBUSY;
		}
		if (tmp_ops->ctl_nr == ops->ctl_nr) {
			P_ERROR("ctl_nr %i already registered!\n", ops->ctl_nr);
			kfree(ops->ctl_table);
			spin_unlock(&appldata_ops_lock);
			return -EBUSY;
		}
	}
	list_add(&ops->list, &appldata_ops_list);
	spin_unlock(&appldata_ops_lock);

	ops->ctl_table[0].ctl_name = CTL_APPLDATA;
	ops->ctl_table[0].procname = appldata_proc_name;
	ops->ctl_table[0].maxlen   = 0;
	ops->ctl_table[0].mode     = S_IRUGO | S_IXUGO;
	ops->ctl_table[0].child    = &ops->ctl_table[2];

	ops->ctl_table[1].ctl_name = 0;

	ops->ctl_table[2].ctl_name = ops->ctl_nr;
	ops->ctl_table[2].procname = ops->name;
	ops->ctl_table[2].mode     = S_IRUGO | S_IWUSR;
	ops->ctl_table[2].proc_handler = appldata_generic_handler;
	ops->ctl_table[2].data = ops;

	ops->ctl_table[3].ctl_name = 0;

	ops->sysctl_header = register_sysctl_table(ops->ctl_table,1);

	P_INFO("%s-ops registered!\n", ops->name);
	return 0;
}

/*
 * appldata_unregister_ops()
 *
 * update ops list, unregister /proc entries, stop DIAG if necessary
 */
void appldata_unregister_ops(struct appldata_ops *ops)
{
	void *table;
	spin_lock(&appldata_ops_lock);
	list_del(&ops->list);
	/* at that point any incoming access will fail */
	table = ops->ctl_table;
	ops->ctl_table = NULL;
	spin_unlock(&appldata_ops_lock);
	unregister_sysctl_table(ops->sysctl_header);
	kfree(table);
	P_INFO("%s-ops unregistered!\n", ops->name);
}
/********************** module-ops management <END> **************************/


/******************************* init / exit *********************************/

static void
appldata_online_cpu(int cpu)
{
	init_virt_timer(&per_cpu(appldata_timer, cpu));
	per_cpu(appldata_timer, cpu).function = appldata_timer_function;
	per_cpu(appldata_timer, cpu).data = (unsigned long)
		&appldata_work;
	atomic_inc(&appldata_expire_count);
	spin_lock(&appldata_timer_lock);
	__appldata_vtimer_setup(APPLDATA_MOD_TIMER);
	spin_unlock(&appldata_timer_lock);
}

static void
appldata_offline_cpu(int cpu)
{
	del_virt_timer(&per_cpu(appldata_timer, cpu));
	if (atomic_dec_and_test(&appldata_expire_count)) {
		atomic_set(&appldata_expire_count, num_online_cpus());
		queue_work(appldata_wq, &appldata_work);
	}
	spin_lock(&appldata_timer_lock);
	__appldata_vtimer_setup(APPLDATA_MOD_TIMER);
	spin_unlock(&appldata_timer_lock);
}

#ifdef CONFIG_HOTPLUG_CPU
static int
appldata_cpu_notify(struct notifier_block *self,
		    unsigned long action, void *hcpu)
{
	switch (action) {
	case CPU_ONLINE:
		appldata_online_cpu((long) hcpu);
		break;
	case CPU_DEAD:
		appldata_offline_cpu((long) hcpu);
		break;
	default:
		break;
	}
	return NOTIFY_OK;
}

static struct notifier_block appldata_nb = {
	.notifier_call = appldata_cpu_notify,
};
#endif

/*
 * appldata_init()
 *
 * init timer, register /proc entries
 */
static int __init appldata_init(void)
{
	int i;

	P_DEBUG("sizeof(parameter_list) = %lu\n",
		sizeof(struct appldata_parameter_list));

	appldata_wq = create_singlethread_workqueue("appldata");
	if (!appldata_wq) {
		P_ERROR("Could not create work queue\n");
		return -ENOMEM;
	}

	for_each_online_cpu(i)
		appldata_online_cpu(i);

	/* Register cpu hotplug notifier */
	register_hotcpu_notifier(&appldata_nb);

	appldata_sysctl_header = register_sysctl_table(appldata_dir_table, 1);
#ifdef MODULE
	appldata_dir_table[0].de->owner = THIS_MODULE;
	appldata_table[0].de->owner = THIS_MODULE;
	appldata_table[1].de->owner = THIS_MODULE;
#endif

	P_DEBUG("Base interface initialized.\n");
	return 0;
}

/*
 * appldata_exit()
 *
 * stop timer, unregister /proc entries
 */
static void __exit appldata_exit(void)
{
	struct list_head *lh;
	struct appldata_ops *ops;
	int rc, i;

	P_DEBUG("Unloading module ...\n");
	/*
	 * ops list should be empty, but just in case something went wrong...
	 */
	spin_lock(&appldata_ops_lock);
	list_for_each(lh, &appldata_ops_list) {
		ops = list_entry(lh, struct appldata_ops, list);
		rc = appldata_diag(ops->record_nr, APPLDATA_STOP_REC,
				(unsigned long) ops->data, ops->size,
				ops->mod_lvl);
		if (rc != 0) {
			P_ERROR("STOP DIAG 0xDC for %s failed, "
				"return code: %d\n", ops->name, rc);
		}
	}
	spin_unlock(&appldata_ops_lock);

	for_each_online_cpu(i)
		appldata_offline_cpu(i);

	appldata_timer_active = 0;

	unregister_sysctl_table(appldata_sysctl_header);

	destroy_workqueue(appldata_wq);
	P_DEBUG("... module unloaded!\n");
}
/**************************** init / exit <END> ******************************/


module_init(appldata_init);
module_exit(appldata_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Gerald Schaefer");
MODULE_DESCRIPTION("Linux-VM Monitor Stream, base infrastructure");

EXPORT_SYMBOL_GPL(appldata_register_ops);
EXPORT_SYMBOL_GPL(appldata_unregister_ops);
EXPORT_SYMBOL_GPL(appldata_diag);

#ifdef MODULE
/*
 * Kernel symbols needed by appldata_mem and appldata_os modules.
 * However, if this file is compiled as a module (for testing only), these
 * symbols are not exported. In this case, we define them locally and export
 * those.
 */
void si_swapinfo(struct sysinfo *val)
{
	val->freeswap = -1ul;
	val->totalswap = -1ul;
}

unsigned long avenrun[3] = {-1 - FIXED_1/200, -1 - FIXED_1/200,
				-1 - FIXED_1/200};
int nr_threads = -1;

void get_full_page_state(struct page_state *ps)
{
	memset(ps, -1, sizeof(struct page_state));
}

unsigned long nr_running(void)
{
	return -1;
}

unsigned long nr_iowait(void)
{
	return -1;
}

/*unsigned long nr_context_switches(void)
{
	return -1;
}*/
#endif /* MODULE */
EXPORT_SYMBOL_GPL(si_swapinfo);
EXPORT_SYMBOL_GPL(nr_threads);
EXPORT_SYMBOL_GPL(nr_running);
EXPORT_SYMBOL_GPL(nr_iowait);
//EXPORT_SYMBOL_GPL(nr_context_switches);