appldata_base.c

linux-2.6.15.6

	__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->active = 1;
		ops->callback(ops->data);	// init record
		rc = appldata_diag(ops->record_nr,
					APPLDATA_START_INTERVAL_REC,
					(unsigned long) ops->data, ops->size);
		if (rc != 0) {
			P_ERROR("START DIAG 0xDC for %s failed, "
				"return code: %d\n", ops->name, rc);
			module_put(ops->owner);
			ops->active = 0;
		} else {
			P_INFO("Monitoring %s data enabled, "
				"DIAG 0xDC started.\n", ops->name);
		}
	} 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);
		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 = kmalloc(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;
	}
	memset(ops->ctl_table, 0, 4*sizeof(struct ctl_table));

	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);
}

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;
#ifdef CONFIG_HOTPLUG_CPU
	case CPU_DEAD:
		appldata_offline_cpu((long) hcpu);
		break;
#endif
	default:
		break;
	}
	return NOTIFY_OK;
}

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

/*
 * 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_cpu_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);
		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);

#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(avenrun);
EXPORT_SYMBOL_GPL(get_full_page_state);
EXPORT_SYMBOL_GPL(nr_running);
EXPORT_SYMBOL_GPL(nr_iowait);
//EXPORT_SYMBOL_GPL(nr_context_switches);