xref: /linux/arch/s390/appldata/appldata_base.c (revision 36ca1195ad7f760a6af3814cb002bd3a3d4b4db1)
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 (C) 2003 IBM Corporation, IBM Deutschland Entwicklung GmbH.
9  *
10  * Author: Gerald Schaefer <geraldsc@de.ibm.com>
11  */
12 
13 #include <linux/config.h>
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/slab.h>
17 #include <linux/errno.h>
18 #include <asm/uaccess.h>
19 #include <asm/io.h>
20 #include <asm/smp.h>
21 #include <linux/interrupt.h>
22 #include <linux/proc_fs.h>
23 #include <linux/page-flags.h>
24 #include <linux/swap.h>
25 #include <linux/pagemap.h>
26 #include <linux/sysctl.h>
27 #include <asm/timer.h>
28 //#include <linux/kernel_stat.h>
29 #include <linux/notifier.h>
30 #include <linux/cpu.h>
31 #include <linux/workqueue.h>
32 
33 #include "appldata.h"
34 
35 
36 #define MY_PRINT_NAME	"appldata"		/* for debug messages, etc. */
37 #define APPLDATA_CPU_INTERVAL	10000		/* default (CPU) time for
38 						   sampling interval in
39 						   milliseconds */
40 
41 #define TOD_MICRO	0x01000			/* nr. of TOD clock units
42 						   for 1 microsecond */
43 #ifndef CONFIG_ARCH_S390X
44 
45 #define APPLDATA_START_INTERVAL_REC 0x00   	/* Function codes for */
46 #define APPLDATA_STOP_REC	    0x01	/* DIAG 0xDC	  */
47 #define APPLDATA_GEN_EVENT_RECORD   0x02
48 #define APPLDATA_START_CONFIG_REC   0x03
49 
50 #else
51 
52 #define APPLDATA_START_INTERVAL_REC 0x80
53 #define APPLDATA_STOP_REC   	    0x81
54 #define APPLDATA_GEN_EVENT_RECORD   0x82
55 #define APPLDATA_START_CONFIG_REC   0x83
56 
57 #endif /* CONFIG_ARCH_S390X */
58 
59 
60 /*
61  * Parameter list for DIAGNOSE X'DC'
62  */
63 #ifndef CONFIG_ARCH_S390X
64 struct appldata_parameter_list {
65 	u16 diag;		/* The DIAGNOSE code X'00DC'          */
66 	u8  function;		/* The function code for the DIAGNOSE */
67 	u8  parlist_length;	/* Length of the parameter list       */
68 	u32 product_id_addr;	/* Address of the 16-byte product ID  */
69 	u16 reserved;
70 	u16 buffer_length;	/* Length of the application data buffer  */
71 	u32 buffer_addr;	/* Address of the application data buffer */
72 };
73 #else
74 struct appldata_parameter_list {
75 	u16 diag;
76 	u8  function;
77 	u8  parlist_length;
78 	u32 unused01;
79 	u16 reserved;
80 	u16 buffer_length;
81 	u32 unused02;
82 	u64 product_id_addr;
83 	u64 buffer_addr;
84 };
85 #endif /* CONFIG_ARCH_S390X */
86 
87 /*
88  * /proc entries (sysctl)
89  */
90 static const char appldata_proc_name[APPLDATA_PROC_NAME_LENGTH] = "appldata";
91 static int appldata_timer_handler(ctl_table *ctl, int write, struct file *filp,
92 				  void __user *buffer, size_t *lenp, loff_t *ppos);
93 static int appldata_interval_handler(ctl_table *ctl, int write,
94 					 struct file *filp,
95 					 void __user *buffer,
96 					 size_t *lenp, loff_t *ppos);
97 
98 static struct ctl_table_header *appldata_sysctl_header;
99 static struct ctl_table appldata_table[] = {
100 	{
101 		.ctl_name	= CTL_APPLDATA_TIMER,
102 		.procname	= "timer",
103 		.mode		= S_IRUGO | S_IWUSR,
104 		.proc_handler	= &appldata_timer_handler,
105 	},
106 	{
107 		.ctl_name	= CTL_APPLDATA_INTERVAL,
108 		.procname	= "interval",
109 		.mode		= S_IRUGO | S_IWUSR,
110 		.proc_handler	= &appldata_interval_handler,
111 	},
112 	{ .ctl_name = 0 }
113 };
114 
115 static struct ctl_table appldata_dir_table[] = {
116 	{
117 		.ctl_name	= CTL_APPLDATA,
118 		.procname	= appldata_proc_name,
119 		.maxlen		= 0,
120 		.mode		= S_IRUGO | S_IXUGO,
121 		.child		= appldata_table,
122 	},
123 	{ .ctl_name = 0 }
124 };
125 
126 /*
127  * Timer
128  */
129 DEFINE_PER_CPU(struct vtimer_list, appldata_timer);
130 static atomic_t appldata_expire_count = ATOMIC_INIT(0);
131 
132 static DEFINE_SPINLOCK(appldata_timer_lock);
133 static int appldata_interval = APPLDATA_CPU_INTERVAL;
134 static int appldata_timer_active;
135 
136 /*
137  * Work queue
138  */
139 static struct workqueue_struct *appldata_wq;
140 static void appldata_work_fn(void *data);
141 static DECLARE_WORK(appldata_work, appldata_work_fn, NULL);
142 
143 
144 /*
145  * Ops list
146  */
147 static DEFINE_SPINLOCK(appldata_ops_lock);
148 static LIST_HEAD(appldata_ops_list);
149 
150 
151 /*************************** timer, work, DIAG *******************************/
152 /*
153  * appldata_timer_function()
154  *
155  * schedule work and reschedule timer
156  */
157 static void appldata_timer_function(unsigned long data, struct pt_regs *regs)
158 {
159 	P_DEBUG("   -= Timer =-\n");
160 	P_DEBUG("CPU: %i, expire_count: %i\n", smp_processor_id(),
161 		atomic_read(&appldata_expire_count));
162 	if (atomic_dec_and_test(&appldata_expire_count)) {
163 		atomic_set(&appldata_expire_count, num_online_cpus());
164 		queue_work(appldata_wq, (struct work_struct *) data);
165 	}
166 }
167 
168 /*
169  * appldata_work_fn()
170  *
171  * call data gathering function for each (active) module
172  */
173 static void appldata_work_fn(void *data)
174 {
175 	struct list_head *lh;
176 	struct appldata_ops *ops;
177 	int i;
178 
179 	P_DEBUG("  -= Work Queue =-\n");
180 	i = 0;
181 	spin_lock(&appldata_ops_lock);
182 	list_for_each(lh, &appldata_ops_list) {
183 		ops = list_entry(lh, struct appldata_ops, list);
184 		P_DEBUG("list_for_each loop: %i) active = %u, name = %s\n",
185 			++i, ops->active, ops->name);
186 		if (ops->active == 1) {
187 			ops->callback(ops->data);
188 		}
189 	}
190 	spin_unlock(&appldata_ops_lock);
191 }
192 
193 /*
194  * appldata_diag()
195  *
196  * prepare parameter list, issue DIAG 0xDC
197  */
198 static int appldata_diag(char record_nr, u16 function, unsigned long buffer,
199 			u16 length)
200 {
201 	unsigned long ry;
202 	struct appldata_product_id {
203 		char prod_nr[7];			/* product nr. */
204 		char prod_fn[2];			/* product function */
205 		char record_nr;				/* record nr. */
206 		char version_nr[2];			/* version */
207 		char release_nr[2];			/* release */
208 		char mod_lvl[2];			/* modification lvl. */
209 	} appldata_product_id = {
210 	/* all strings are EBCDIC, record_nr is byte */
211 		.prod_nr    = {0xD3, 0xC9, 0xD5, 0xE4,
212 				0xE7, 0xD2, 0xD9},	/* "LINUXKR" */
213 		.prod_fn    = {0xD5, 0xD3},		/* "NL" */
214 		.record_nr  = record_nr,
215 		.version_nr = {0xF2, 0xF6},		/* "26" */
216 		.release_nr = {0xF0, 0xF1},		/* "01" */
217 		.mod_lvl    = {0xF0, 0xF0},		/* "00" */
218 	};
219 	struct appldata_parameter_list appldata_parameter_list = {
220 				.diag = 0xDC,
221 				.function = function,
222 				.parlist_length =
223 					sizeof(appldata_parameter_list),
224 				.buffer_length = length,
225 				.product_id_addr =
226 					(unsigned long) &appldata_product_id,
227 				.buffer_addr = virt_to_phys((void *) buffer)
228 	};
229 
230 	if (!MACHINE_IS_VM)
231 		return -ENOSYS;
232 	ry = -1;
233 	asm volatile(
234 			"diag %1,%0,0xDC\n\t"
235 			: "=d" (ry) : "d" (&(appldata_parameter_list)) : "cc");
236 	return (int) ry;
237 }
238 /************************ timer, work, DIAG <END> ****************************/
239 
240 
241 /****************************** /proc stuff **********************************/
242 
243 /*
244  * appldata_mod_vtimer_wrap()
245  *
246  * wrapper function for mod_virt_timer(), because smp_call_function_on()
247  * accepts only one parameter.
248  */
249 static void __appldata_mod_vtimer_wrap(void *p) {
250 	struct {
251 		struct vtimer_list *timer;
252 		u64    expires;
253 	} *args = p;
254 	mod_virt_timer(args->timer, args->expires);
255 }
256 
257 #define APPLDATA_ADD_TIMER	0
258 #define APPLDATA_DEL_TIMER	1
259 #define APPLDATA_MOD_TIMER	2
260 
261 /*
262  * __appldata_vtimer_setup()
263  *
264  * Add, delete or modify virtual timers on all online cpus.
265  * The caller needs to get the appldata_timer_lock spinlock.
266  */
267 static void
268 __appldata_vtimer_setup(int cmd)
269 {
270 	u64 per_cpu_interval;
271 	int i;
272 
273 	switch (cmd) {
274 	case APPLDATA_ADD_TIMER:
275 		if (appldata_timer_active)
276 			break;
277 		per_cpu_interval = (u64) (appldata_interval*1000 /
278 					  num_online_cpus()) * TOD_MICRO;
279 		for_each_online_cpu(i) {
280 			per_cpu(appldata_timer, i).expires = per_cpu_interval;
281 			smp_call_function_on(add_virt_timer_periodic,
282 					     &per_cpu(appldata_timer, i),
283 					     0, 1, i);
284 		}
285 		appldata_timer_active = 1;
286 		P_INFO("Monitoring timer started.\n");
287 		break;
288 	case APPLDATA_DEL_TIMER:
289 		for_each_online_cpu(i)
290 			del_virt_timer(&per_cpu(appldata_timer, i));
291 		if (!appldata_timer_active)
292 			break;
293 		appldata_timer_active = 0;
294 		atomic_set(&appldata_expire_count, num_online_cpus());
295 		P_INFO("Monitoring timer stopped.\n");
296 		break;
297 	case APPLDATA_MOD_TIMER:
298 		per_cpu_interval = (u64) (appldata_interval*1000 /
299 					  num_online_cpus()) * TOD_MICRO;
300 		if (!appldata_timer_active)
301 			break;
302 		for_each_online_cpu(i) {
303 			struct {
304 				struct vtimer_list *timer;
305 				u64    expires;
306 			} args;
307 			args.timer = &per_cpu(appldata_timer, i);
308 			args.expires = per_cpu_interval;
309 			smp_call_function_on(__appldata_mod_vtimer_wrap,
310 					     &args, 0, 1, i);
311 		}
312 	}
313 }
314 
315 /*
316  * appldata_timer_handler()
317  *
318  * Start/Stop timer, show status of timer (0 = not active, 1 = active)
319  */
320 static int
321 appldata_timer_handler(ctl_table *ctl, int write, struct file *filp,
322 			   void __user *buffer, size_t *lenp, loff_t *ppos)
323 {
324 	int len;
325 	char buf[2];
326 
327 	if (!*lenp || *ppos) {
328 		*lenp = 0;
329 		return 0;
330 	}
331 	if (!write) {
332 		len = sprintf(buf, appldata_timer_active ? "1\n" : "0\n");
333 		if (len > *lenp)
334 			len = *lenp;
335 		if (copy_to_user(buffer, buf, len))
336 			return -EFAULT;
337 		goto out;
338 	}
339 	len = *lenp;
340 	if (copy_from_user(buf, buffer, len > sizeof(buf) ? sizeof(buf) : len))
341 		return -EFAULT;
342 	spin_lock(&appldata_timer_lock);
343 	if (buf[0] == '1')
344 		__appldata_vtimer_setup(APPLDATA_ADD_TIMER);
345 	else if (buf[0] == '0')
346 		__appldata_vtimer_setup(APPLDATA_DEL_TIMER);
347 	spin_unlock(&appldata_timer_lock);
348 out:
349 	*lenp = len;
350 	*ppos += len;
351 	return 0;
352 }
353 
354 /*
355  * appldata_interval_handler()
356  *
357  * Set (CPU) timer interval for collection of data (in milliseconds), show
358  * current timer interval.
359  */
360 static int
361 appldata_interval_handler(ctl_table *ctl, int write, struct file *filp,
362 			   void __user *buffer, size_t *lenp, loff_t *ppos)
363 {
364 	int len, interval;
365 	char buf[16];
366 
367 	if (!*lenp || *ppos) {
368 		*lenp = 0;
369 		return 0;
370 	}
371 	if (!write) {
372 		len = sprintf(buf, "%i\n", appldata_interval);
373 		if (len > *lenp)
374 			len = *lenp;
375 		if (copy_to_user(buffer, buf, len))
376 			return -EFAULT;
377 		goto out;
378 	}
379 	len = *lenp;
380 	if (copy_from_user(buf, buffer, len > sizeof(buf) ? sizeof(buf) : len)) {
381 		return -EFAULT;
382 	}
383 	sscanf(buf, "%i", &interval);
384 	if (interval <= 0) {
385 		P_ERROR("Timer CPU interval has to be > 0!\n");
386 		return -EINVAL;
387 	}
388 
389 	spin_lock(&appldata_timer_lock);
390 	appldata_interval = interval;
391 	__appldata_vtimer_setup(APPLDATA_MOD_TIMER);
392 	spin_unlock(&appldata_timer_lock);
393 
394 	P_INFO("Monitoring CPU interval set to %u milliseconds.\n",
395 		 interval);
396 out:
397 	*lenp = len;
398 	*ppos += len;
399 	return 0;
400 }
401 
402 /*
403  * appldata_generic_handler()
404  *
405  * Generic start/stop monitoring and DIAG, show status of
406  * monitoring (0 = not in process, 1 = in process)
407  */
408 static int
409 appldata_generic_handler(ctl_table *ctl, int write, struct file *filp,
410 			   void __user *buffer, size_t *lenp, loff_t *ppos)
411 {
412 	struct appldata_ops *ops = NULL, *tmp_ops;
413 	int rc, len, found;
414 	char buf[2];
415 	struct list_head *lh;
416 
417 	found = 0;
418 	spin_lock(&appldata_ops_lock);
419 	list_for_each(lh, &appldata_ops_list) {
420 		tmp_ops = list_entry(lh, struct appldata_ops, list);
421 		if (&tmp_ops->ctl_table[2] == ctl) {
422 			found = 1;
423 		}
424 	}
425 	if (!found) {
426 		spin_unlock(&appldata_ops_lock);
427 		return -ENODEV;
428 	}
429 	ops = ctl->data;
430 	if (!try_module_get(ops->owner)) {	// protect this function
431 		spin_unlock(&appldata_ops_lock);
432 		return -ENODEV;
433 	}
434 	spin_unlock(&appldata_ops_lock);
435 
436 	if (!*lenp || *ppos) {
437 		*lenp = 0;
438 		module_put(ops->owner);
439 		return 0;
440 	}
441 	if (!write) {
442 		len = sprintf(buf, ops->active ? "1\n" : "0\n");
443 		if (len > *lenp)
444 			len = *lenp;
445 		if (copy_to_user(buffer, buf, len)) {
446 			module_put(ops->owner);
447 			return -EFAULT;
448 		}
449 		goto out;
450 	}
451 	len = *lenp;
452 	if (copy_from_user(buf, buffer,
453 			   len > sizeof(buf) ? sizeof(buf) : len)) {
454 		module_put(ops->owner);
455 		return -EFAULT;
456 	}
457 
458 	spin_lock(&appldata_ops_lock);
459 	if ((buf[0] == '1') && (ops->active == 0)) {
460 		// protect work queue callback
461 		if (!try_module_get(ops->owner)) {
462 			spin_unlock(&appldata_ops_lock);
463 			module_put(ops->owner);
464 			return -ENODEV;
465 		}
466 		ops->active = 1;
467 		ops->callback(ops->data);	// init record
468 		rc = appldata_diag(ops->record_nr,
469 					APPLDATA_START_INTERVAL_REC,
470 					(unsigned long) ops->data, ops->size);
471 		if (rc != 0) {
472 			P_ERROR("START DIAG 0xDC for %s failed, "
473 				"return code: %d\n", ops->name, rc);
474 			module_put(ops->owner);
475 			ops->active = 0;
476 		} else {
477 			P_INFO("Monitoring %s data enabled, "
478 				"DIAG 0xDC started.\n", ops->name);
479 		}
480 	} else if ((buf[0] == '0') && (ops->active == 1)) {
481 		ops->active = 0;
482 		rc = appldata_diag(ops->record_nr, APPLDATA_STOP_REC,
483 				(unsigned long) ops->data, ops->size);
484 		if (rc != 0) {
485 			P_ERROR("STOP DIAG 0xDC for %s failed, "
486 				"return code: %d\n", ops->name, rc);
487 		} else {
488 			P_INFO("Monitoring %s data disabled, "
489 				"DIAG 0xDC stopped.\n", ops->name);
490 		}
491 		module_put(ops->owner);
492 	}
493 	spin_unlock(&appldata_ops_lock);
494 out:
495 	*lenp = len;
496 	*ppos += len;
497 	module_put(ops->owner);
498 	return 0;
499 }
500 
501 /*************************** /proc stuff <END> *******************************/
502 
503 
504 /************************* module-ops management *****************************/
505 /*
506  * appldata_register_ops()
507  *
508  * update ops list, register /proc/sys entries
509  */
510 int appldata_register_ops(struct appldata_ops *ops)
511 {
512 	struct list_head *lh;
513 	struct appldata_ops *tmp_ops;
514 	int i;
515 
516 	i = 0;
517 
518 	if ((ops->size > APPLDATA_MAX_REC_SIZE) ||
519 		(ops->size < 0)){
520 		P_ERROR("Invalid size of %s record = %i, maximum = %i!\n",
521 			ops->name, ops->size, APPLDATA_MAX_REC_SIZE);
522 		return -ENOMEM;
523 	}
524 	if ((ops->ctl_nr == CTL_APPLDATA) ||
525 	    (ops->ctl_nr == CTL_APPLDATA_TIMER) ||
526 	    (ops->ctl_nr == CTL_APPLDATA_INTERVAL)) {
527 		P_ERROR("ctl_nr %i already in use!\n", ops->ctl_nr);
528 		return -EBUSY;
529 	}
530 	ops->ctl_table = kmalloc(4*sizeof(struct ctl_table), GFP_KERNEL);
531 	if (ops->ctl_table == NULL) {
532 		P_ERROR("Not enough memory for %s ctl_table!\n", ops->name);
533 		return -ENOMEM;
534 	}
535 	memset(ops->ctl_table, 0, 4*sizeof(struct ctl_table));
536 
537 	spin_lock(&appldata_ops_lock);
538 	list_for_each(lh, &appldata_ops_list) {
539 		tmp_ops = list_entry(lh, struct appldata_ops, list);
540 		P_DEBUG("register_ops loop: %i) name = %s, ctl = %i\n",
541 			++i, tmp_ops->name, tmp_ops->ctl_nr);
542 		P_DEBUG("Comparing %s (ctl %i) with %s (ctl %i)\n",
543 			tmp_ops->name, tmp_ops->ctl_nr, ops->name,
544 			ops->ctl_nr);
545 		if (strncmp(tmp_ops->name, ops->name,
546 				APPLDATA_PROC_NAME_LENGTH) == 0) {
547 			P_ERROR("Name \"%s\" already registered!\n", ops->name);
548 			kfree(ops->ctl_table);
549 			spin_unlock(&appldata_ops_lock);
550 			return -EBUSY;
551 		}
552 		if (tmp_ops->ctl_nr == ops->ctl_nr) {
553 			P_ERROR("ctl_nr %i already registered!\n", ops->ctl_nr);
554 			kfree(ops->ctl_table);
555 			spin_unlock(&appldata_ops_lock);
556 			return -EBUSY;
557 		}
558 	}
559 	list_add(&ops->list, &appldata_ops_list);
560 	spin_unlock(&appldata_ops_lock);
561 
562 	ops->ctl_table[0].ctl_name = CTL_APPLDATA;
563 	ops->ctl_table[0].procname = appldata_proc_name;
564 	ops->ctl_table[0].maxlen   = 0;
565 	ops->ctl_table[0].mode     = S_IRUGO | S_IXUGO;
566 	ops->ctl_table[0].child    = &ops->ctl_table[2];
567 
568 	ops->ctl_table[1].ctl_name = 0;
569 
570 	ops->ctl_table[2].ctl_name = ops->ctl_nr;
571 	ops->ctl_table[2].procname = ops->name;
572 	ops->ctl_table[2].mode     = S_IRUGO | S_IWUSR;
573 	ops->ctl_table[2].proc_handler = appldata_generic_handler;
574 	ops->ctl_table[2].data = ops;
575 
576 	ops->ctl_table[3].ctl_name = 0;
577 
578 	ops->sysctl_header = register_sysctl_table(ops->ctl_table,1);
579 
580 	P_INFO("%s-ops registered!\n", ops->name);
581 	return 0;
582 }
583 
584 /*
585  * appldata_unregister_ops()
586  *
587  * update ops list, unregister /proc entries, stop DIAG if necessary
588  */
589 void appldata_unregister_ops(struct appldata_ops *ops)
590 {
591 	spin_lock(&appldata_ops_lock);
592 	unregister_sysctl_table(ops->sysctl_header);
593 	list_del(&ops->list);
594 	kfree(ops->ctl_table);
595 	ops->ctl_table = NULL;
596 	spin_unlock(&appldata_ops_lock);
597 	P_INFO("%s-ops unregistered!\n", ops->name);
598 }
599 /********************** module-ops management <END> **************************/
600 
601 
602 /******************************* init / exit *********************************/
603 
604 static void
605 appldata_online_cpu(int cpu)
606 {
607 	init_virt_timer(&per_cpu(appldata_timer, cpu));
608 	per_cpu(appldata_timer, cpu).function = appldata_timer_function;
609 	per_cpu(appldata_timer, cpu).data = (unsigned long)
610 		&appldata_work;
611 	atomic_inc(&appldata_expire_count);
612 	spin_lock(&appldata_timer_lock);
613 	__appldata_vtimer_setup(APPLDATA_MOD_TIMER);
614 	spin_unlock(&appldata_timer_lock);
615 }
616 
617 static void
618 appldata_offline_cpu(int cpu)
619 {
620 	del_virt_timer(&per_cpu(appldata_timer, cpu));
621 	if (atomic_dec_and_test(&appldata_expire_count)) {
622 		atomic_set(&appldata_expire_count, num_online_cpus());
623 		queue_work(appldata_wq, &appldata_work);
624 	}
625 	spin_lock(&appldata_timer_lock);
626 	__appldata_vtimer_setup(APPLDATA_MOD_TIMER);
627 	spin_unlock(&appldata_timer_lock);
628 }
629 
630 static int
631 appldata_cpu_notify(struct notifier_block *self,
632 		    unsigned long action, void *hcpu)
633 {
634 	switch (action) {
635 	case CPU_ONLINE:
636 		appldata_online_cpu((long) hcpu);
637 		break;
638 #ifdef CONFIG_HOTPLUG_CPU
639 	case CPU_DEAD:
640 		appldata_offline_cpu((long) hcpu);
641 		break;
642 #endif
643 	default:
644 		break;
645 	}
646 	return NOTIFY_OK;
647 }
648 
649 static struct notifier_block __devinitdata appldata_nb = {
650 	.notifier_call = appldata_cpu_notify,
651 };
652 
653 /*
654  * appldata_init()
655  *
656  * init timer, register /proc entries
657  */
658 static int __init appldata_init(void)
659 {
660 	int i;
661 
662 	P_DEBUG("sizeof(parameter_list) = %lu\n",
663 		sizeof(struct appldata_parameter_list));
664 
665 	appldata_wq = create_singlethread_workqueue("appldata");
666 	if (!appldata_wq) {
667 		P_ERROR("Could not create work queue\n");
668 		return -ENOMEM;
669 	}
670 
671 	for_each_online_cpu(i)
672 		appldata_online_cpu(i);
673 
674 	/* Register cpu hotplug notifier */
675 	register_cpu_notifier(&appldata_nb);
676 
677 	appldata_sysctl_header = register_sysctl_table(appldata_dir_table, 1);
678 #ifdef MODULE
679 	appldata_dir_table[0].de->owner = THIS_MODULE;
680 	appldata_table[0].de->owner = THIS_MODULE;
681 	appldata_table[1].de->owner = THIS_MODULE;
682 #endif
683 
684 	P_DEBUG("Base interface initialized.\n");
685 	return 0;
686 }
687 
688 /*
689  * appldata_exit()
690  *
691  * stop timer, unregister /proc entries
692  */
693 static void __exit appldata_exit(void)
694 {
695 	struct list_head *lh;
696 	struct appldata_ops *ops;
697 	int rc, i;
698 
699 	P_DEBUG("Unloading module ...\n");
700 	/*
701 	 * ops list should be empty, but just in case something went wrong...
702 	 */
703 	spin_lock(&appldata_ops_lock);
704 	list_for_each(lh, &appldata_ops_list) {
705 		ops = list_entry(lh, struct appldata_ops, list);
706 		rc = appldata_diag(ops->record_nr, APPLDATA_STOP_REC,
707 				(unsigned long) ops->data, ops->size);
708 		if (rc != 0) {
709 			P_ERROR("STOP DIAG 0xDC for %s failed, "
710 				"return code: %d\n", ops->name, rc);
711 		}
712 	}
713 	spin_unlock(&appldata_ops_lock);
714 
715 	for_each_online_cpu(i)
716 		appldata_offline_cpu(i);
717 
718 	appldata_timer_active = 0;
719 
720 	unregister_sysctl_table(appldata_sysctl_header);
721 
722 	destroy_workqueue(appldata_wq);
723 	P_DEBUG("... module unloaded!\n");
724 }
725 /**************************** init / exit <END> ******************************/
726 
727 
728 module_init(appldata_init);
729 module_exit(appldata_exit);
730 MODULE_LICENSE("GPL");
731 MODULE_AUTHOR("Gerald Schaefer");
732 MODULE_DESCRIPTION("Linux-VM Monitor Stream, base infrastructure");
733 
734 EXPORT_SYMBOL_GPL(appldata_register_ops);
735 EXPORT_SYMBOL_GPL(appldata_unregister_ops);
736 
737 #ifdef MODULE
738 /*
739  * Kernel symbols needed by appldata_mem and appldata_os modules.
740  * However, if this file is compiled as a module (for testing only), these
741  * symbols are not exported. In this case, we define them locally and export
742  * those.
743  */
744 void si_swapinfo(struct sysinfo *val)
745 {
746 	val->freeswap = -1ul;
747 	val->totalswap = -1ul;
748 }
749 
750 unsigned long avenrun[3] = {-1 - FIXED_1/200, -1 - FIXED_1/200,
751 				-1 - FIXED_1/200};
752 int nr_threads = -1;
753 
754 void get_full_page_state(struct page_state *ps)
755 {
756 	memset(ps, -1, sizeof(struct page_state));
757 }
758 
759 unsigned long nr_running(void)
760 {
761 	return -1;
762 }
763 
764 unsigned long nr_iowait(void)
765 {
766 	return -1;
767 }
768 
769 /*unsigned long nr_context_switches(void)
770 {
771 	return -1;
772 }*/
773 #endif /* MODULE */
774 EXPORT_SYMBOL_GPL(si_swapinfo);
775 EXPORT_SYMBOL_GPL(nr_threads);
776 EXPORT_SYMBOL_GPL(avenrun);
777 EXPORT_SYMBOL_GPL(get_full_page_state);
778 EXPORT_SYMBOL_GPL(nr_running);
779 EXPORT_SYMBOL_GPL(nr_iowait);
780 //EXPORT_SYMBOL_GPL(nr_context_switches);
781