[lttng-ust.git] / liblttng-ust / lttng-probes.c

/*
 * lttng-probes.c
 *
 * Holds LTTng probes registry.
 *
 * Copyright 2010-2012 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; only
 * version 2.1 of the License.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#define _LGPL_SOURCE
#include <string.h>
#include <errno.h>
#include <urcu/list.h>
#include <urcu/hlist.h>
#include <lttng/ust-events.h>
#include <lttng/tracepoint.h>
#include "tracepoint-internal.h"
#include <assert.h>
#include <helper.h>
#include <ctype.h>

#include "lttng-tracer-core.h"
#include "jhash.h"
#include "error.h"
#include "ust-events-internal.h"

/*
 * probe list is protected by ust_lock()/ust_unlock().
 */
static CDS_LIST_HEAD(_probe_list);

/*
 * List of probes registered by not yet processed.
 */
static CDS_LIST_HEAD(lazy_probe_init);

/*
 * lazy_nesting counter ensures we don't trigger lazy probe registration
 * fixup while we are performing the fixup. It is protected by the ust
 * mutex.
 */
static int lazy_nesting;

/*
 * Called under ust lock.
 */
static
int check_event_provider(struct lttng_probe_desc *desc)
{
	int i;
	size_t provider_name_len;

	provider_name_len = strnlen(desc->provider,
				LTTNG_UST_SYM_NAME_LEN - 1);
	for (i = 0; i < desc->nr_events; i++) {
		if (strncmp(desc->event_desc[i]->name,
				desc->provider,
				provider_name_len))
			return 0;	/* provider mismatch */
	}
	return 1;
}

/*
 * Called under ust lock.
 */
static
void lttng_lazy_probe_register(struct lttng_probe_desc *desc)
{
	struct lttng_probe_desc *iter;
	struct cds_list_head *probe_list;

	/*
	 * Each provider enforce that every event name begins with the
	 * provider name. Check this in an assertion for extra
	 * carefulness. This ensures we cannot have duplicate event
	 * names across providers.
	 */
	assert(check_event_provider(desc));

	/*
	 * The provider ensures there are no duplicate event names.
	 * Duplicated TRACEPOINT_EVENT event names would generate a
	 * compile-time error due to duplicated symbol names.
	 */

	/*
	 * We sort the providers by struct lttng_probe_desc pointer
	 * address.
	 */
	probe_list = &_probe_list;
	cds_list_for_each_entry_reverse(iter, probe_list, head) {
		BUG_ON(iter == desc); /* Should never be in the list twice */
		if (iter < desc) {
			/* We belong to the location right after iter. */
			cds_list_add(&desc->head, &iter->head);
			goto desc_added;
		}
	}
	/* We should be added at the head of the list */
	cds_list_add(&desc->head, probe_list);
desc_added:
	DBG("just registered probe %s containing %u events",
		desc->provider, desc->nr_events);
}

/*
 * Called under ust lock.
 */
static
void fixup_lazy_probes(void)
{
	struct lttng_probe_desc *iter, *tmp;
	int ret;

	lazy_nesting++;
	cds_list_for_each_entry_safe(iter, tmp,
			&lazy_probe_init, lazy_init_head) {
		lttng_lazy_probe_register(iter);
		iter->lazy = 0;
		cds_list_del(&iter->lazy_init_head);
	}
	ret = lttng_fix_pending_events();
	assert(!ret);
	lazy_nesting--;
}

/*
 * Called under ust lock.
 */
struct cds_list_head *lttng_get_probe_list_head(void)
{
	if (!lazy_nesting && !cds_list_empty(&lazy_probe_init))
		fixup_lazy_probes();
	return &_probe_list;
}

static
int check_provider_version(struct lttng_probe_desc *desc)
{
	/*
	 * Check tracepoint provider version compatibility.
	 */
	if (desc->major <= LTTNG_UST_PROVIDER_MAJOR) {
		DBG("Provider \"%s\" accepted, version %u.%u is compatible "
			"with LTTng UST provider version %u.%u.",
			desc->provider, desc->major, desc->minor,
			LTTNG_UST_PROVIDER_MAJOR,
			LTTNG_UST_PROVIDER_MINOR);
		if (desc->major < LTTNG_UST_PROVIDER_MAJOR) {
			DBG("However, some LTTng UST features might not be "
				"available for this provider unless it is "
				"recompiled against a more recent LTTng UST.");
		}
		return 1;		/* accept */
	} else {
		ERR("Provider \"%s\" rejected, version %u.%u is incompatible "
			"with LTTng UST provider version %u.%u. Please upgrade "
			"LTTng UST.",
			desc->provider, desc->major, desc->minor,
			LTTNG_UST_PROVIDER_MAJOR,
			LTTNG_UST_PROVIDER_MINOR);
		return 0;		/* reject */
	}
}


int lttng_probe_register(struct lttng_probe_desc *desc)
{
	int ret = 0;

	lttng_ust_fixup_tls();

	/*
	 * If version mismatch, don't register, but don't trigger assert
	 * on caller. The version check just prints an error.
	 */
	if (!check_provider_version(desc))
		return 0;

	ust_lock_nocheck();

	cds_list_add(&desc->lazy_init_head, &lazy_probe_init);
	desc->lazy = 1;
	DBG("adding probe %s containing %u events to lazy registration list",
		desc->provider, desc->nr_events);
	/*
	 * If there is at least one active session, we need to register
	 * the probe immediately, since we cannot delay event
	 * registration because they are needed ASAP.
	 */
	if (lttng_session_active())
		fixup_lazy_probes();

	lttng_fix_pending_event_notifiers();

	ust_unlock();
	return ret;
}

/* Backward compatibility with UST 2.0 */
int ltt_probe_register(struct lttng_probe_desc *desc)
{
	return lttng_probe_register(desc);
}

void lttng_probe_unregister(struct lttng_probe_desc *desc)
{
	lttng_ust_fixup_tls();

	if (!check_provider_version(desc))
		return;

	ust_lock_nocheck();
	if (!desc->lazy)
		cds_list_del(&desc->head);
	else
		cds_list_del(&desc->lazy_init_head);

	lttng_probe_provider_unregister_events(desc);
	DBG("just unregistered probes of provider %s", desc->provider);

	ust_unlock();
}

/* Backward compatibility with UST 2.0 */
void ltt_probe_unregister(struct lttng_probe_desc *desc)
{
	lttng_probe_unregister(desc);
}

void lttng_probes_prune_event_list(struct lttng_ust_tracepoint_list *list)
{
	struct tp_list_entry *list_entry, *tmp;

	cds_list_for_each_entry_safe(list_entry, tmp, &list->head, head) {
		cds_list_del(&list_entry->head);
		free(list_entry);
	}
}

/*
 * called with UST lock held.
 */
int lttng_probes_get_event_list(struct lttng_ust_tracepoint_list *list)
{
	struct lttng_probe_desc *probe_desc;
	int i;
	struct cds_list_head *probe_list;

	probe_list = lttng_get_probe_list_head();
	CDS_INIT_LIST_HEAD(&list->head);
	cds_list_for_each_entry(probe_desc, probe_list, head) {
		for (i = 0; i < probe_desc->nr_events; i++) {
			struct tp_list_entry *list_entry;

			list_entry = zmalloc(sizeof(*list_entry));
			if (!list_entry)
				goto err_nomem;
			cds_list_add(&list_entry->head, &list->head);
			strncpy(list_entry->tp.name,
				probe_desc->event_desc[i]->name,
				LTTNG_UST_SYM_NAME_LEN);
			list_entry->tp.name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
			if (!probe_desc->event_desc[i]->loglevel) {
				list_entry->tp.loglevel = TRACE_DEFAULT;
			} else {
				list_entry->tp.loglevel = *(*probe_desc->event_desc[i]->loglevel);
			}
		}
	}
	if (cds_list_empty(&list->head))
		list->iter = NULL;
	else
		list->iter =
			cds_list_first_entry(&list->head, struct tp_list_entry, head);
	return 0;

err_nomem:
	lttng_probes_prune_event_list(list);
	return -ENOMEM;
}

/*
 * Return current iteration position, advance internal iterator to next.
 * Return NULL if end of list.
 */
struct lttng_ust_tracepoint_iter *
	lttng_ust_tracepoint_list_get_iter_next(struct lttng_ust_tracepoint_list *list)
{
	struct tp_list_entry *entry;

	if (!list->iter)
		return NULL;
	entry = list->iter;
	if (entry->head.next == &list->head)
		list->iter = NULL;
	else
		list->iter = cds_list_entry(entry->head.next,
				struct tp_list_entry, head);
	return &entry->tp;
}

void lttng_probes_prune_field_list(struct lttng_ust_field_list *list)
{
	struct tp_field_list_entry *list_entry, *tmp;

	cds_list_for_each_entry_safe(list_entry, tmp, &list->head, head) {
		cds_list_del(&list_entry->head);
		free(list_entry);
	}
}

/*
 * called with UST lock held.
 */
int lttng_probes_get_field_list(struct lttng_ust_field_list *list)
{
	struct lttng_probe_desc *probe_desc;
	int i;
	struct cds_list_head *probe_list;

	probe_list = lttng_get_probe_list_head();
	CDS_INIT_LIST_HEAD(&list->head);
	cds_list_for_each_entry(probe_desc, probe_list, head) {
		for (i = 0; i < probe_desc->nr_events; i++) {
			const struct lttng_event_desc *event_desc =
				probe_desc->event_desc[i];
			int j;

			if (event_desc->nr_fields == 0) {
				/* Events without fields. */
				struct tp_field_list_entry *list_entry;

				list_entry = zmalloc(sizeof(*list_entry));
				if (!list_entry)
					goto err_nomem;
				cds_list_add(&list_entry->head, &list->head);
				strncpy(list_entry->field.event_name,
					event_desc->name,
					LTTNG_UST_SYM_NAME_LEN);
				list_entry->field.event_name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
				list_entry->field.field_name[0] = '\0';
				list_entry->field.type = LTTNG_UST_FIELD_OTHER;
				if (!event_desc->loglevel) {
					list_entry->field.loglevel = TRACE_DEFAULT;
				} else {
					list_entry->field.loglevel = *(*event_desc->loglevel);
				}
				list_entry->field.nowrite = 1;
			}

			for (j = 0; j < event_desc->nr_fields; j++) {
				const struct lttng_event_field *event_field =
					&event_desc->fields[j];
				struct tp_field_list_entry *list_entry;

				list_entry = zmalloc(sizeof(*list_entry));
				if (!list_entry)
					goto err_nomem;
				cds_list_add(&list_entry->head, &list->head);
				strncpy(list_entry->field.event_name,
					event_desc->name,
					LTTNG_UST_SYM_NAME_LEN);
				list_entry->field.event_name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
				strncpy(list_entry->field.field_name,
					event_field->name,
					LTTNG_UST_SYM_NAME_LEN);
				list_entry->field.field_name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
				switch (event_field->type.atype) {
				case atype_integer:
					list_entry->field.type = LTTNG_UST_FIELD_INTEGER;
					break;
				case atype_string:
					list_entry->field.type = LTTNG_UST_FIELD_STRING;
					break;
				case atype_array:
					if (event_field->type.u.legacy.array.elem_type.atype != atype_integer
						|| event_field->type.u.legacy.array.elem_type.u.basic.integer.encoding == lttng_encode_none)
						list_entry->field.type = LTTNG_UST_FIELD_OTHER;
					else
						list_entry->field.type = LTTNG_UST_FIELD_STRING;
					break;
				case atype_array_nestable:
					if (event_field->type.u.array_nestable.elem_type->atype != atype_integer
						|| event_field->type.u.array_nestable.elem_type->u.integer.encoding == lttng_encode_none)
						list_entry->field.type = LTTNG_UST_FIELD_OTHER;
					else
						list_entry->field.type = LTTNG_UST_FIELD_STRING;
					break;
				case atype_sequence:
					if (event_field->type.u.legacy.sequence.elem_type.atype != atype_integer
						|| event_field->type.u.legacy.sequence.elem_type.u.basic.integer.encoding == lttng_encode_none)
						list_entry->field.type = LTTNG_UST_FIELD_OTHER;
					else
						list_entry->field.type = LTTNG_UST_FIELD_STRING;
					break;
				case atype_sequence_nestable:
					if (event_field->type.u.sequence_nestable.elem_type->atype != atype_integer
						|| event_field->type.u.sequence_nestable.elem_type->u.integer.encoding == lttng_encode_none)
						list_entry->field.type = LTTNG_UST_FIELD_OTHER;
					else
						list_entry->field.type = LTTNG_UST_FIELD_STRING;
					break;
				case atype_float:
					list_entry->field.type = LTTNG_UST_FIELD_FLOAT;
					break;
				case atype_enum:	/* Fall-through */
				case atype_enum_nestable:
					list_entry->field.type = LTTNG_UST_FIELD_ENUM;
					break;
				default:
					list_entry->field.type = LTTNG_UST_FIELD_OTHER;
				}
				if (!event_desc->loglevel) {
					list_entry->field.loglevel = TRACE_DEFAULT;
				} else {
					list_entry->field.loglevel = *(*event_desc->loglevel);
				}
				list_entry->field.nowrite = event_field->nowrite;
			}
		}
	}
	if (cds_list_empty(&list->head))
		list->iter = NULL;
	else
		list->iter =
			cds_list_first_entry(&list->head,
				struct tp_field_list_entry, head);
	return 0;

err_nomem:
	lttng_probes_prune_field_list(list);
	return -ENOMEM;
}

/*
 * Return current iteration position, advance internal iterator to next.
 * Return NULL if end of list.
 */
struct lttng_ust_field_iter *
	lttng_ust_field_list_get_iter_next(struct lttng_ust_field_list *list)
{
	struct tp_field_list_entry *entry;

	if (!list->iter)
		return NULL;
	entry = list->iter;
	if (entry->head.next == &list->head)
		list->iter = NULL;
	else
		list->iter = cds_list_entry(entry->head.next,
				struct tp_field_list_entry, head);
	return &entry->field;
}
Commit	Line	Data
ce5aef0b	1	/*
7dd08bec	2	* lttng-probes.c
ce5aef0b	3	*
ce5aef0b MD	4	* Holds LTTng probes registry.
ce5aef0b MD	5	*
e92f3e28 MD	6	* Copyright 2010-2012 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	7	*
	8	* This library is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU Lesser General Public
	10	* License as published by the Free Software Foundation; only
	11	* version 2.1 of the License.
	12	*
	13	* This library is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	16	* Lesser General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU Lesser General Public
	19	* License along with this library; if not, write to the Free Software
	20	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
ce5aef0b MD	21	*/
ce5aef0b MD	22
3fbec7dc	23	#define _LGPL_SOURCE
8d8a24c8 MD	24	#include <string.h>
	25	#include <errno.h>
	26	#include <urcu/list.h>
1f18504e	27	#include <urcu/hlist.h>
4318ae1b	28	#include <lttng/ust-events.h>
902e1379	29	#include <lttng/tracepoint.h>
d8de1354	30	#include "tracepoint-internal.h"
a3bb4b27	31	#include <assert.h>
c8fcf224	32	#include <helper.h>
48740cab	33	#include <ctype.h>
ce5aef0b	34
7dd08bec	35	#include "lttng-tracer-core.h"
1f18504e MD	36	#include "jhash.h"
1f18504e MD	37	#include "error.h"
d8d2416d	38	#include "ust-events-internal.h"
8165c8da MD	39
8165c8da MD	40	/*
17dfb34b	41	* probe list is protected by ust_lock()/ust_unlock().
8165c8da	42	*/
ac69b35b	43	static CDS_LIST_HEAD(_probe_list);
e58095ef	44
6715d7d1 MD	45	/*
	46	* List of probes registered by not yet processed.
	47	*/
	48	static CDS_LIST_HEAD(lazy_probe_init);
df854e41	49
6715d7d1 MD	50	/*
	51	* lazy_nesting counter ensures we don't trigger lazy probe registration
	52	* fixup while we are performing the fixup. It is protected by the ust
	53	* mutex.
	54	*/
	55	static int lazy_nesting;
df854e41	56
6715d7d1 MD	57	/*
	58	* Called under ust lock.
	59	*/
ce5aef0b	60	static
48205d60	61	int check_event_provider(struct lttng_probe_desc *desc)
ce5aef0b	62	{
ce5aef0b	63	int i;
48205d60	64	size_t provider_name_len;
ce5aef0b	65
48205d60 MD	66	provider_name_len = strnlen(desc->provider,
	67	LTTNG_UST_SYM_NAME_LEN - 1);
	68	for (i = 0; i < desc->nr_events; i++) {
	69	if (strncmp(desc->event_desc[i]->name,
	70	desc->provider,
	71	provider_name_len))
	72	return 0; /* provider mismatch */
ce5aef0b	73	}
48205d60	74	return 1;
ce5aef0b MD	75	}
ce5aef0b MD	76
6715d7d1 MD	77	/*
	78	* Called under ust lock.
	79	*/
	80	static
	81	void lttng_lazy_probe_register(struct lttng_probe_desc *desc)
ce5aef0b	82	{
df854e41	83	struct lttng_probe_desc *iter;
ac69b35b	84	struct cds_list_head *probe_list;
48205d60	85
ce5aef0b	86	/*
48205d60 MD	87	* Each provider enforce that every event name begins with the
	88	* provider name. Check this in an assertion for extra
	89	* carefulness. This ensures we cannot have duplicate event
	90	* names across providers.
	91	*/
	92	assert(check_event_provider(desc));
	93
	94	/*
	95	* The provider ensures there are no duplicate event names.
	96	* Duplicated TRACEPOINT_EVENT event names would generate a
	97	* compile-time error due to duplicated symbol names.
ce5aef0b	98	*/
df854e41 MD	99
	100	/*
	101	* We sort the providers by struct lttng_probe_desc pointer
	102	* address.
	103	*/
6715d7d1	104	probe_list = &_probe_list;
ac69b35b	105	cds_list_for_each_entry_reverse(iter, probe_list, head) {
df854e41 MD	106	BUG_ON(iter == desc); /* Should never be in the list twice */
	107	if (iter < desc) {
	108	/* We belong to the location right after iter. */
	109	cds_list_add(&desc->head, &iter->head);
	110	goto desc_added;
	111	}
	112	}
	113	/* We should be added at the head of the list */
ac69b35b	114	cds_list_add(&desc->head, probe_list);
df854e41	115	desc_added:
e81a53af MD	116	DBG("just registered probe %s containing %u events",
e81a53af MD	117	desc->provider, desc->nr_events);
6715d7d1 MD	118	}
	119
	120	/*
	121	* Called under ust lock.
	122	*/
	123	static
	124	void fixup_lazy_probes(void)
	125	{
	126	struct lttng_probe_desc iter, tmp;
5f733922	127	int ret;
6715d7d1 MD	128
	129	lazy_nesting++;
	130	cds_list_for_each_entry_safe(iter, tmp,
	131	&lazy_probe_init, lazy_init_head) {
	132	lttng_lazy_probe_register(iter);
	133	iter->lazy = 0;
	134	cds_list_del(&iter->lazy_init_head);
	135	}
5f733922 MD	136	ret = lttng_fix_pending_events();
5f733922 MD	137	assert(!ret);
6715d7d1 MD	138	lazy_nesting--;
	139	}
	140
	141	/*
	142	* Called under ust lock.
	143	*/
	144	struct cds_list_head *lttng_get_probe_list_head(void)
	145	{
	146	if (!lazy_nesting && !cds_list_empty(&lazy_probe_init))
	147	fixup_lazy_probes();
	148	return &_probe_list;
	149	}
	150
71d31690 MD	151	static
	152	int check_provider_version(struct lttng_probe_desc *desc)
	153	{
	154	/*
	155	* Check tracepoint provider version compatibility.
	156	*/
	157	if (desc->major <= LTTNG_UST_PROVIDER_MAJOR) {
	158	DBG("Provider \"%s\" accepted, version %u.%u is compatible "
	159	"with LTTng UST provider version %u.%u.",
	160	desc->provider, desc->major, desc->minor,
	161	LTTNG_UST_PROVIDER_MAJOR,
	162	LTTNG_UST_PROVIDER_MINOR);
	163	if (desc->major < LTTNG_UST_PROVIDER_MAJOR) {
	164	DBG("However, some LTTng UST features might not be "
	165	"available for this provider unless it is "
	166	"recompiled against a more recent LTTng UST.");
	167	}
	168	return 1; /* accept */
	169	} else {
	170	ERR("Provider \"%s\" rejected, version %u.%u is incompatible "
	171	"with LTTng UST provider version %u.%u. Please upgrade "
	172	"LTTng UST.",
	173	desc->provider, desc->major, desc->minor,
	174	LTTNG_UST_PROVIDER_MAJOR,
	175	LTTNG_UST_PROVIDER_MINOR);
	176	return 0; /* reject */
	177	}
	178	}
	179
	180
6715d7d1 MD	181	int lttng_probe_register(struct lttng_probe_desc *desc)
	182	{
	183	int ret = 0;
	184
c362addf MD	185	lttng_ust_fixup_tls();
c362addf MD	186
71d31690 MD	187	/*
	188	* If version mismatch, don't register, but don't trigger assert
	189	* on caller. The version check just prints an error.
	190	*/
	191	if (!check_provider_version(desc))
	192	return 0;
	193
3327ac33	194	ust_lock_nocheck();
6715d7d1	195
6715d7d1 MD	196	cds_list_add(&desc->lazy_init_head, &lazy_probe_init);
	197	desc->lazy = 1;
	198	DBG("adding probe %s containing %u events to lazy registration list",
	199	desc->provider, desc->nr_events);
	200	/*
	201	* If there is at least one active session, we need to register
	202	* the probe immediately, since we cannot delay event
	203	* registration because they are needed ASAP.
	204	*/
	205	if (lttng_session_active())
	206	fixup_lazy_probes();
0fdd0b89	207
d8d2416d FD	208	lttng_fix_pending_event_notifiers();
d8d2416d FD	209
17dfb34b	210	ust_unlock();
ce5aef0b MD	211	return ret;
ce5aef0b MD	212	}
ce5aef0b	213
7dd08bec MD	214	/* Backward compatibility with UST 2.0 */
	215	int ltt_probe_register(struct lttng_probe_desc *desc)
	216	{
	217	return lttng_probe_register(desc);
	218	}
	219
	220	void lttng_probe_unregister(struct lttng_probe_desc *desc)
ce5aef0b	221	{
c362addf MD	222	lttng_ust_fixup_tls();
c362addf MD	223
71d31690 MD	224	if (!check_provider_version(desc))
	225	return;
	226
3327ac33	227	ust_lock_nocheck();
6715d7d1 MD	228	if (!desc->lazy)
	229	cds_list_del(&desc->head);
	230	else
	231	cds_list_del(&desc->lazy_init_head);
2c05c691 FD	232
	233	lttng_probe_provider_unregister_events(desc);
	234	DBG("just unregistered probes of provider %s", desc->provider);
	235
17dfb34b	236	ust_unlock();
ce5aef0b	237	}
ce5aef0b	238
7dd08bec MD	239	/* Backward compatibility with UST 2.0 */
	240	void ltt_probe_unregister(struct lttng_probe_desc *desc)
	241	{
	242	lttng_probe_unregister(desc);
	243	}
	244
7dd08bec	245	void lttng_probes_prune_event_list(struct lttng_ust_tracepoint_list *list)
c8fcf224 MD	246	{
	247	struct tp_list_entry list_entry, tmp;
	248
	249	cds_list_for_each_entry_safe(list_entry, tmp, &list->head, head) {
	250	cds_list_del(&list_entry->head);
	251	free(list_entry);
	252	}
	253	}
	254
	255	/*
	256	* called with UST lock held.
	257	*/
7dd08bec	258	int lttng_probes_get_event_list(struct lttng_ust_tracepoint_list *list)
c8fcf224 MD	259	{
	260	struct lttng_probe_desc *probe_desc;
	261	int i;
ac69b35b	262	struct cds_list_head *probe_list;
c8fcf224	263
ac69b35b	264	probe_list = lttng_get_probe_list_head();
c8fcf224	265	CDS_INIT_LIST_HEAD(&list->head);
ac69b35b	266	cds_list_for_each_entry(probe_desc, probe_list, head) {
c8fcf224 MD	267	for (i = 0; i < probe_desc->nr_events; i++) {
	268	struct tp_list_entry *list_entry;
	269
	270	list_entry = zmalloc(sizeof(*list_entry));
	271	if (!list_entry)
	272	goto err_nomem;
	273	cds_list_add(&list_entry->head, &list->head);
	274	strncpy(list_entry->tp.name,
	275	probe_desc->event_desc[i]->name,
	276	LTTNG_UST_SYM_NAME_LEN);
	277	list_entry->tp.name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
	278	if (!probe_desc->event_desc[i]->loglevel) {
882a56d7	279	list_entry->tp.loglevel = TRACE_DEFAULT;
c8fcf224	280	} else {
882a56d7	281	list_entry->tp.loglevel = (probe_desc->event_desc[i]->loglevel);
c8fcf224 MD	282	}
	283	}
	284	}
	285	if (cds_list_empty(&list->head))
	286	list->iter = NULL;
	287	else
	288	list->iter =
	289	cds_list_first_entry(&list->head, struct tp_list_entry, head);
	290	return 0;
	291
	292	err_nomem:
7dd08bec	293	lttng_probes_prune_event_list(list);
c8fcf224 MD	294	return -ENOMEM;
	295	}
	296
	297	/*
	298	* Return current iteration position, advance internal iterator to next.
	299	* Return NULL if end of list.
	300	*/
	301	struct lttng_ust_tracepoint_iter *
	302	lttng_ust_tracepoint_list_get_iter_next(struct lttng_ust_tracepoint_list *list)
	303	{
	304	struct tp_list_entry *entry;
	305
	306	if (!list->iter)
	307	return NULL;
	308	entry = list->iter;
	309	if (entry->head.next == &list->head)
	310	list->iter = NULL;
	311	else
	312	list->iter = cds_list_entry(entry->head.next,
	313	struct tp_list_entry, head);
	314	return &entry->tp;
	315	}
1f18504e	316
7dd08bec	317	void lttng_probes_prune_field_list(struct lttng_ust_field_list *list)
06d4f27e MD	318	{
	319	struct tp_field_list_entry list_entry, tmp;
	320
	321	cds_list_for_each_entry_safe(list_entry, tmp, &list->head, head) {
	322	cds_list_del(&list_entry->head);
	323	free(list_entry);
	324	}
	325	}
	326
	327	/*
	328	* called with UST lock held.
	329	*/
7dd08bec	330	int lttng_probes_get_field_list(struct lttng_ust_field_list *list)
06d4f27e MD	331	{
	332	struct lttng_probe_desc *probe_desc;
	333	int i;
ac69b35b	334	struct cds_list_head *probe_list;
06d4f27e	335
ac69b35b	336	probe_list = lttng_get_probe_list_head();
06d4f27e	337	CDS_INIT_LIST_HEAD(&list->head);
ac69b35b	338	cds_list_for_each_entry(probe_desc, probe_list, head) {
06d4f27e MD	339	for (i = 0; i < probe_desc->nr_events; i++) {
	340	const struct lttng_event_desc *event_desc =
	341	probe_desc->event_desc[i];
	342	int j;
	343
26329f26 MD	344	if (event_desc->nr_fields == 0) {
	345	/* Events without fields. */
	346	struct tp_field_list_entry *list_entry;
	347
	348	list_entry = zmalloc(sizeof(*list_entry));
	349	if (!list_entry)
	350	goto err_nomem;
	351	cds_list_add(&list_entry->head, &list->head);
	352	strncpy(list_entry->field.event_name,
	353	event_desc->name,
	354	LTTNG_UST_SYM_NAME_LEN);
	355	list_entry->field.event_name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
	356	list_entry->field.field_name[0] = '\0';
	357	list_entry->field.type = LTTNG_UST_FIELD_OTHER;
	358	if (!event_desc->loglevel) {
	359	list_entry->field.loglevel = TRACE_DEFAULT;
	360	} else {
	361	list_entry->field.loglevel = (event_desc->loglevel);
	362	}
	363	list_entry->field.nowrite = 1;
	364	}
	365
06d4f27e MD	366	for (j = 0; j < event_desc->nr_fields; j++) {
	367	const struct lttng_event_field *event_field =
	368	&event_desc->fields[j];
	369	struct tp_field_list_entry *list_entry;
	370
	371	list_entry = zmalloc(sizeof(*list_entry));
	372	if (!list_entry)
	373	goto err_nomem;
	374	cds_list_add(&list_entry->head, &list->head);
	375	strncpy(list_entry->field.event_name,
	376	event_desc->name,
	377	LTTNG_UST_SYM_NAME_LEN);
	378	list_entry->field.event_name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
	379	strncpy(list_entry->field.field_name,
	380	event_field->name,
	381	LTTNG_UST_SYM_NAME_LEN);
	382	list_entry->field.field_name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
40003310 MD	383	switch (event_field->type.atype) {
	384	case atype_integer:
	385	list_entry->field.type = LTTNG_UST_FIELD_INTEGER;
	386	break;
	387	case atype_string:
	388	list_entry->field.type = LTTNG_UST_FIELD_STRING;
	389	break;
	390	case atype_array:
218deb69 MD	391	if (event_field->type.u.legacy.array.elem_type.atype != atype_integer
	392	\|\| event_field->type.u.legacy.array.elem_type.u.basic.integer.encoding == lttng_encode_none)
	393	list_entry->field.type = LTTNG_UST_FIELD_OTHER;
	394	else
	395	list_entry->field.type = LTTNG_UST_FIELD_STRING;
	396	break;
	397	case atype_array_nestable:
	398	if (event_field->type.u.array_nestable.elem_type->atype != atype_integer
	399	\|\| event_field->type.u.array_nestable.elem_type->u.integer.encoding == lttng_encode_none)
40003310 MD	400	list_entry->field.type = LTTNG_UST_FIELD_OTHER;
	401	else
	402	list_entry->field.type = LTTNG_UST_FIELD_STRING;
	403	break;
	404	case atype_sequence:
218deb69 MD	405	if (event_field->type.u.legacy.sequence.elem_type.atype != atype_integer
	406	\|\| event_field->type.u.legacy.sequence.elem_type.u.basic.integer.encoding == lttng_encode_none)
	407	list_entry->field.type = LTTNG_UST_FIELD_OTHER;
	408	else
	409	list_entry->field.type = LTTNG_UST_FIELD_STRING;
	410	break;
	411	case atype_sequence_nestable:
	412	if (event_field->type.u.sequence_nestable.elem_type->atype != atype_integer
	413	\|\| event_field->type.u.sequence_nestable.elem_type->u.integer.encoding == lttng_encode_none)
40003310 MD	414	list_entry->field.type = LTTNG_UST_FIELD_OTHER;
	415	else
	416	list_entry->field.type = LTTNG_UST_FIELD_STRING;
	417	break;
	418	case atype_float:
	419	list_entry->field.type = LTTNG_UST_FIELD_FLOAT;
	420	break;
218deb69 MD	421	case atype_enum: /* Fall-through */
218deb69 MD	422	case atype_enum_nestable:
40003310 MD	423	list_entry->field.type = LTTNG_UST_FIELD_ENUM;
	424	break;
	425	default:
	426	list_entry->field.type = LTTNG_UST_FIELD_OTHER;
	427	}
06d4f27e MD	428	if (!event_desc->loglevel) {
	429	list_entry->field.loglevel = TRACE_DEFAULT;
	430	} else {
	431	list_entry->field.loglevel = (event_desc->loglevel);
	432	}
180901e6	433	list_entry->field.nowrite = event_field->nowrite;
06d4f27e MD	434	}
	435	}
	436	}
	437	if (cds_list_empty(&list->head))
	438	list->iter = NULL;
	439	else
	440	list->iter =
	441	cds_list_first_entry(&list->head,
	442	struct tp_field_list_entry, head);
	443	return 0;
	444
	445	err_nomem:
7dd08bec	446	lttng_probes_prune_field_list(list);
06d4f27e MD	447	return -ENOMEM;
	448	}
	449
	450	/*
	451	* Return current iteration position, advance internal iterator to next.
	452	* Return NULL if end of list.
	453	*/
	454	struct lttng_ust_field_iter *
	455	lttng_ust_field_list_get_iter_next(struct lttng_ust_field_list *list)
	456	{
	457	struct tp_field_list_entry *entry;
	458
	459	if (!list->iter)
	460	return NULL;
	461	entry = list->iter;
	462	if (entry->head.next == &list->head)
	463	list->iter = NULL;
	464	else
	465	list->iter = cds_list_entry(entry->head.next,
	466	struct tp_field_list_entry, head);
	467	return &entry->field;
	468	}