[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
 */

#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"

/*
 * 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
const struct lttng_probe_desc *find_provider(const char *provider)
{
	struct lttng_probe_desc *iter;
	struct cds_list_head *probe_list;

	probe_list = lttng_get_probe_list_head();
	cds_list_for_each_entry(iter, probe_list, head) {
		if (!strcmp(iter->provider, provider))
			return iter;
	}
	return NULL;
}

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();

	/*
	 * Check if the provider has already been registered.
	 */
	if (find_provider(desc->provider)) {
		ret = -EEXIST;
		goto end;
	}
	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();
end:
	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);
	DBG("just unregistered probe %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.array.elem_type.atype != atype_integer
						|| event_field->type.u.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_sequence:
					if (event_field->type.u.sequence.elem_type.atype != atype_integer
						|| event_field->type.u.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_float:
					list_entry->field.type = LTTNG_UST_FIELD_FLOAT;
					break;
				case atype_enum:
					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
8d8a24c8 MD	23	#include <string.h>
	24	#include <errno.h>
	25	#include <urcu/list.h>
1f18504e	26	#include <urcu/hlist.h>
4318ae1b	27	#include <lttng/ust-events.h>
902e1379	28	#include <lttng/tracepoint.h>
d8de1354	29	#include "tracepoint-internal.h"
a3bb4b27	30	#include <assert.h>
c8fcf224	31	#include <helper.h>
48740cab	32	#include <ctype.h>
ce5aef0b	33
7dd08bec	34	#include "lttng-tracer-core.h"
1f18504e MD	35	#include "jhash.h"
1f18504e MD	36	#include "error.h"
8165c8da MD	37
8165c8da MD	38	/*
17dfb34b	39	* probe list is protected by ust_lock()/ust_unlock().
8165c8da	40	*/
ac69b35b	41	static CDS_LIST_HEAD(_probe_list);
e58095ef	42
6715d7d1 MD	43	/*
	44	* List of probes registered by not yet processed.
	45	*/
	46	static CDS_LIST_HEAD(lazy_probe_init);
df854e41	47
6715d7d1 MD	48	/*
	49	* lazy_nesting counter ensures we don't trigger lazy probe registration
	50	* fixup while we are performing the fixup. It is protected by the ust
	51	* mutex.
	52	*/
	53	static int lazy_nesting;
df854e41	54
6715d7d1 MD	55	/*
	56	* Called under ust lock.
	57	*/
ce5aef0b	58	static
48205d60	59	int check_event_provider(struct lttng_probe_desc *desc)
ce5aef0b	60	{
ce5aef0b	61	int i;
48205d60	62	size_t provider_name_len;
ce5aef0b	63
48205d60 MD	64	provider_name_len = strnlen(desc->provider,
	65	LTTNG_UST_SYM_NAME_LEN - 1);
	66	for (i = 0; i < desc->nr_events; i++) {
	67	if (strncmp(desc->event_desc[i]->name,
	68	desc->provider,
	69	provider_name_len))
	70	return 0; /* provider mismatch */
ce5aef0b	71	}
48205d60	72	return 1;
ce5aef0b MD	73	}
ce5aef0b MD	74
6715d7d1 MD	75	/*
	76	* Called under ust lock.
	77	*/
	78	static
	79	void lttng_lazy_probe_register(struct lttng_probe_desc *desc)
ce5aef0b	80	{
df854e41	81	struct lttng_probe_desc *iter;
ac69b35b	82	struct cds_list_head *probe_list;
48205d60	83
ce5aef0b	84	/*
48205d60 MD	85	* Each provider enforce that every event name begins with the
	86	* provider name. Check this in an assertion for extra
	87	* carefulness. This ensures we cannot have duplicate event
	88	* names across providers.
	89	*/
	90	assert(check_event_provider(desc));
	91
	92	/*
	93	* The provider ensures there are no duplicate event names.
	94	* Duplicated TRACEPOINT_EVENT event names would generate a
	95	* compile-time error due to duplicated symbol names.
ce5aef0b	96	*/
df854e41 MD	97
	98	/*
	99	* We sort the providers by struct lttng_probe_desc pointer
	100	* address.
	101	*/
6715d7d1	102	probe_list = &_probe_list;
ac69b35b	103	cds_list_for_each_entry_reverse(iter, probe_list, head) {
df854e41 MD	104	BUG_ON(iter == desc); /* Should never be in the list twice */
	105	if (iter < desc) {
	106	/* We belong to the location right after iter. */
	107	cds_list_add(&desc->head, &iter->head);
	108	goto desc_added;
	109	}
	110	}
	111	/* We should be added at the head of the list */
ac69b35b	112	cds_list_add(&desc->head, probe_list);
df854e41	113	desc_added:
e81a53af MD	114	DBG("just registered probe %s containing %u events",
e81a53af MD	115	desc->provider, desc->nr_events);
6715d7d1 MD	116	}
	117
	118	/*
	119	* Called under ust lock.
	120	*/
	121	static
	122	void fixup_lazy_probes(void)
	123	{
	124	struct lttng_probe_desc iter, tmp;
5f733922	125	int ret;
6715d7d1 MD	126
	127	lazy_nesting++;
	128	cds_list_for_each_entry_safe(iter, tmp,
	129	&lazy_probe_init, lazy_init_head) {
	130	lttng_lazy_probe_register(iter);
	131	iter->lazy = 0;
	132	cds_list_del(&iter->lazy_init_head);
	133	}
5f733922 MD	134	ret = lttng_fix_pending_events();
5f733922 MD	135	assert(!ret);
6715d7d1 MD	136	lazy_nesting--;
	137	}
	138
	139	/*
	140	* Called under ust lock.
	141	*/
	142	struct cds_list_head *lttng_get_probe_list_head(void)
	143	{
	144	if (!lazy_nesting && !cds_list_empty(&lazy_probe_init))
	145	fixup_lazy_probes();
	146	return &_probe_list;
	147	}
	148
	149	static
	150	const struct lttng_probe_desc find_provider(const char provider)
	151	{
	152	struct lttng_probe_desc *iter;
	153	struct cds_list_head *probe_list;
	154
	155	probe_list = lttng_get_probe_list_head();
	156	cds_list_for_each_entry(iter, probe_list, head) {
	157	if (!strcmp(iter->provider, provider))
	158	return iter;
	159	}
	160	return NULL;
	161	}
	162
71d31690 MD	163	static
	164	int check_provider_version(struct lttng_probe_desc *desc)
	165	{
	166	/*
	167	* Check tracepoint provider version compatibility.
	168	*/
	169	if (desc->major <= LTTNG_UST_PROVIDER_MAJOR) {
	170	DBG("Provider \"%s\" accepted, version %u.%u is compatible "
	171	"with LTTng UST provider version %u.%u.",
	172	desc->provider, desc->major, desc->minor,
	173	LTTNG_UST_PROVIDER_MAJOR,
	174	LTTNG_UST_PROVIDER_MINOR);
	175	if (desc->major < LTTNG_UST_PROVIDER_MAJOR) {
	176	DBG("However, some LTTng UST features might not be "
	177	"available for this provider unless it is "
	178	"recompiled against a more recent LTTng UST.");
	179	}
	180	return 1; /* accept */
	181	} else {
	182	ERR("Provider \"%s\" rejected, version %u.%u is incompatible "
	183	"with LTTng UST provider version %u.%u. Please upgrade "
	184	"LTTng UST.",
	185	desc->provider, desc->major, desc->minor,
	186	LTTNG_UST_PROVIDER_MAJOR,
	187	LTTNG_UST_PROVIDER_MINOR);
	188	return 0; /* reject */
	189	}
	190	}
	191
	192
6715d7d1 MD	193	int lttng_probe_register(struct lttng_probe_desc *desc)
	194	{
	195	int ret = 0;
	196
18f50698 MD	197	lttng_ust_fixup_tls();
18f50698 MD	198
71d31690 MD	199	/*
	200	* If version mismatch, don't register, but don't trigger assert
	201	* on caller. The version check just prints an error.
	202	*/
	203	if (!check_provider_version(desc))
	204	return 0;
	205
3327ac33	206	ust_lock_nocheck();
6715d7d1 MD	207
	208	/*
	209	* Check if the provider has already been registered.
	210	*/
	211	if (find_provider(desc->provider)) {
	212	ret = -EEXIST;
	213	goto end;
	214	}
	215	cds_list_add(&desc->lazy_init_head, &lazy_probe_init);
	216	desc->lazy = 1;
	217	DBG("adding probe %s containing %u events to lazy registration list",
	218	desc->provider, desc->nr_events);
	219	/*
	220	* If there is at least one active session, we need to register
	221	* the probe immediately, since we cannot delay event
	222	* registration because they are needed ASAP.
	223	*/
	224	if (lttng_session_active())
	225	fixup_lazy_probes();
ce5aef0b	226	end:
17dfb34b	227	ust_unlock();
ce5aef0b MD	228	return ret;
ce5aef0b MD	229	}
ce5aef0b	230
7dd08bec MD	231	/* Backward compatibility with UST 2.0 */
	232	int ltt_probe_register(struct lttng_probe_desc *desc)
	233	{
	234	return lttng_probe_register(desc);
	235	}
	236
	237	void lttng_probe_unregister(struct lttng_probe_desc *desc)
ce5aef0b	238	{
18f50698 MD	239	lttng_ust_fixup_tls();
18f50698 MD	240
71d31690 MD	241	if (!check_provider_version(desc))
	242	return;
	243
3327ac33	244	ust_lock_nocheck();
6715d7d1 MD	245	if (!desc->lazy)
	246	cds_list_del(&desc->head);
	247	else
	248	cds_list_del(&desc->lazy_init_head);
e81a53af	249	DBG("just unregistered probe %s", desc->provider);
17dfb34b	250	ust_unlock();
ce5aef0b	251	}
ce5aef0b	252
7dd08bec MD	253	/* Backward compatibility with UST 2.0 */
	254	void ltt_probe_unregister(struct lttng_probe_desc *desc)
	255	{
	256	lttng_probe_unregister(desc);
	257	}
	258
7dd08bec	259	void lttng_probes_prune_event_list(struct lttng_ust_tracepoint_list *list)
c8fcf224 MD	260	{
	261	struct tp_list_entry list_entry, tmp;
	262
	263	cds_list_for_each_entry_safe(list_entry, tmp, &list->head, head) {
	264	cds_list_del(&list_entry->head);
	265	free(list_entry);
	266	}
	267	}
	268
	269	/*
	270	* called with UST lock held.
	271	*/
7dd08bec	272	int lttng_probes_get_event_list(struct lttng_ust_tracepoint_list *list)
c8fcf224 MD	273	{
	274	struct lttng_probe_desc *probe_desc;
	275	int i;
ac69b35b	276	struct cds_list_head *probe_list;
c8fcf224	277
ac69b35b	278	probe_list = lttng_get_probe_list_head();
c8fcf224	279	CDS_INIT_LIST_HEAD(&list->head);
ac69b35b	280	cds_list_for_each_entry(probe_desc, probe_list, head) {
c8fcf224 MD	281	for (i = 0; i < probe_desc->nr_events; i++) {
	282	struct tp_list_entry *list_entry;
	283
	284	list_entry = zmalloc(sizeof(*list_entry));
	285	if (!list_entry)
	286	goto err_nomem;
	287	cds_list_add(&list_entry->head, &list->head);
	288	strncpy(list_entry->tp.name,
	289	probe_desc->event_desc[i]->name,
	290	LTTNG_UST_SYM_NAME_LEN);
	291	list_entry->tp.name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
	292	if (!probe_desc->event_desc[i]->loglevel) {
882a56d7	293	list_entry->tp.loglevel = TRACE_DEFAULT;
c8fcf224	294	} else {
882a56d7	295	list_entry->tp.loglevel = (probe_desc->event_desc[i]->loglevel);
c8fcf224 MD	296	}
	297	}
	298	}
	299	if (cds_list_empty(&list->head))
	300	list->iter = NULL;
	301	else
	302	list->iter =
	303	cds_list_first_entry(&list->head, struct tp_list_entry, head);
	304	return 0;
	305
	306	err_nomem:
7dd08bec	307	lttng_probes_prune_event_list(list);
c8fcf224 MD	308	return -ENOMEM;
	309	}
	310
	311	/*
	312	* Return current iteration position, advance internal iterator to next.
	313	* Return NULL if end of list.
	314	*/
	315	struct lttng_ust_tracepoint_iter *
	316	lttng_ust_tracepoint_list_get_iter_next(struct lttng_ust_tracepoint_list *list)
	317	{
	318	struct tp_list_entry *entry;
	319
	320	if (!list->iter)
	321	return NULL;
	322	entry = list->iter;
	323	if (entry->head.next == &list->head)
	324	list->iter = NULL;
	325	else
	326	list->iter = cds_list_entry(entry->head.next,
	327	struct tp_list_entry, head);
	328	return &entry->tp;
	329	}
1f18504e	330
7dd08bec	331	void lttng_probes_prune_field_list(struct lttng_ust_field_list *list)
06d4f27e MD	332	{
	333	struct tp_field_list_entry list_entry, tmp;
	334
	335	cds_list_for_each_entry_safe(list_entry, tmp, &list->head, head) {
	336	cds_list_del(&list_entry->head);
	337	free(list_entry);
	338	}
	339	}
	340
	341	/*
	342	* called with UST lock held.
	343	*/
7dd08bec	344	int lttng_probes_get_field_list(struct lttng_ust_field_list *list)
06d4f27e MD	345	{
	346	struct lttng_probe_desc *probe_desc;
	347	int i;
ac69b35b	348	struct cds_list_head *probe_list;
06d4f27e	349
ac69b35b	350	probe_list = lttng_get_probe_list_head();
06d4f27e	351	CDS_INIT_LIST_HEAD(&list->head);
ac69b35b	352	cds_list_for_each_entry(probe_desc, probe_list, head) {
06d4f27e MD	353	for (i = 0; i < probe_desc->nr_events; i++) {
	354	const struct lttng_event_desc *event_desc =
	355	probe_desc->event_desc[i];
	356	int j;
	357
26329f26 MD	358	if (event_desc->nr_fields == 0) {
	359	/* Events without fields. */
	360	struct tp_field_list_entry *list_entry;
	361
	362	list_entry = zmalloc(sizeof(*list_entry));
	363	if (!list_entry)
	364	goto err_nomem;
	365	cds_list_add(&list_entry->head, &list->head);
	366	strncpy(list_entry->field.event_name,
	367	event_desc->name,
	368	LTTNG_UST_SYM_NAME_LEN);
	369	list_entry->field.event_name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
	370	list_entry->field.field_name[0] = '\0';
	371	list_entry->field.type = LTTNG_UST_FIELD_OTHER;
	372	if (!event_desc->loglevel) {
	373	list_entry->field.loglevel = TRACE_DEFAULT;
	374	} else {
	375	list_entry->field.loglevel = (event_desc->loglevel);
	376	}
	377	list_entry->field.nowrite = 1;
	378	}
	379
06d4f27e MD	380	for (j = 0; j < event_desc->nr_fields; j++) {
	381	const struct lttng_event_field *event_field =
	382	&event_desc->fields[j];
	383	struct tp_field_list_entry *list_entry;
	384
	385	list_entry = zmalloc(sizeof(*list_entry));
	386	if (!list_entry)
	387	goto err_nomem;
	388	cds_list_add(&list_entry->head, &list->head);
	389	strncpy(list_entry->field.event_name,
	390	event_desc->name,
	391	LTTNG_UST_SYM_NAME_LEN);
	392	list_entry->field.event_name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
	393	strncpy(list_entry->field.field_name,
	394	event_field->name,
	395	LTTNG_UST_SYM_NAME_LEN);
	396	list_entry->field.field_name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
40003310 MD	397	switch (event_field->type.atype) {
	398	case atype_integer:
	399	list_entry->field.type = LTTNG_UST_FIELD_INTEGER;
	400	break;
	401	case atype_string:
	402	list_entry->field.type = LTTNG_UST_FIELD_STRING;
	403	break;
	404	case atype_array:
	405	if (event_field->type.u.array.elem_type.atype != atype_integer
	406	\|\| event_field->type.u.array.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:
	412	if (event_field->type.u.sequence.elem_type.atype != atype_integer
	413	\|\| event_field->type.u.sequence.elem_type.u.basic.integer.encoding == lttng_encode_none)
	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;
	421	case atype_enum:
	422	list_entry->field.type = LTTNG_UST_FIELD_ENUM;
	423	break;
	424	default:
	425	list_entry->field.type = LTTNG_UST_FIELD_OTHER;
	426	}
06d4f27e MD	427	if (!event_desc->loglevel) {
	428	list_entry->field.loglevel = TRACE_DEFAULT;
	429	} else {
	430	list_entry->field.loglevel = (event_desc->loglevel);
	431	}
180901e6	432	list_entry->field.nowrite = event_field->nowrite;
06d4f27e MD	433	}
	434	}
	435	}
	436	if (cds_list_empty(&list->head))
	437	list->iter = NULL;
	438	else
	439	list->iter =
	440	cds_list_first_entry(&list->head,
	441	struct tp_field_list_entry, head);
	442	return 0;
	443
	444	err_nomem:
7dd08bec	445	lttng_probes_prune_field_list(list);
06d4f27e MD	446	return -ENOMEM;
	447	}
	448
	449	/*
	450	* Return current iteration position, advance internal iterator to next.
	451	* Return NULL if end of list.
	452	*/
	453	struct lttng_ust_field_iter *
	454	lttng_ust_field_list_get_iter_next(struct lttng_ust_field_list *list)
	455	{
	456	struct tp_field_list_entry *entry;
	457
	458	if (!list->iter)
	459	return NULL;
	460	entry = list->iter;
	461	if (entry->head.next == &list->head)
	462	list->iter = NULL;
	463	else
	464	list->iter = cds_list_entry(entry->head.next,
	465	struct tp_field_list_entry, head);
	466	return &entry->field;
	467	}