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

/*
 * SPDX-License-Identifier: LGPL-2.1-only
 *
 * Copyright 2010-2012 (C) Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * Holds LTTng probes registry.
 */

#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;
}

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();
}

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	/*
c0c0989a	2	* SPDX-License-Identifier: LGPL-2.1-only
ce5aef0b	3	*
c0c0989a	4	* Copyright 2010-2012 (C) Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
e92f3e28	5	*
c0c0989a	6	* Holds LTTng probes registry.
ce5aef0b MD	7	*/
ce5aef0b MD	8
3fbec7dc	9	#define _LGPL_SOURCE
8d8a24c8 MD	10	#include <string.h>
	11	#include <errno.h>
	12	#include <urcu/list.h>
1f18504e	13	#include <urcu/hlist.h>
4318ae1b	14	#include <lttng/ust-events.h>
902e1379	15	#include <lttng/tracepoint.h>
d8de1354	16	#include "tracepoint-internal.h"
a3bb4b27	17	#include <assert.h>
c8fcf224	18	#include <helper.h>
48740cab	19	#include <ctype.h>
ce5aef0b	20
7dd08bec	21	#include "lttng-tracer-core.h"
1f18504e MD	22	#include "jhash.h"
1f18504e MD	23	#include "error.h"
d8d2416d	24	#include "ust-events-internal.h"
8165c8da MD	25
8165c8da MD	26	/*
17dfb34b	27	* probe list is protected by ust_lock()/ust_unlock().
8165c8da	28	*/
ac69b35b	29	static CDS_LIST_HEAD(_probe_list);
e58095ef	30
6715d7d1 MD	31	/*
	32	* List of probes registered by not yet processed.
	33	*/
	34	static CDS_LIST_HEAD(lazy_probe_init);
df854e41	35
6715d7d1 MD	36	/*
	37	* lazy_nesting counter ensures we don't trigger lazy probe registration
	38	* fixup while we are performing the fixup. It is protected by the ust
	39	* mutex.
	40	*/
	41	static int lazy_nesting;
df854e41	42
6715d7d1 MD	43	/*
	44	* Called under ust lock.
	45	*/
ce5aef0b	46	static
48205d60	47	int check_event_provider(struct lttng_probe_desc *desc)
ce5aef0b	48	{
ce5aef0b	49	int i;
48205d60	50	size_t provider_name_len;
ce5aef0b	51
48205d60 MD	52	provider_name_len = strnlen(desc->provider,
	53	LTTNG_UST_SYM_NAME_LEN - 1);
	54	for (i = 0; i < desc->nr_events; i++) {
	55	if (strncmp(desc->event_desc[i]->name,
	56	desc->provider,
	57	provider_name_len))
	58	return 0; /* provider mismatch */
ce5aef0b	59	}
48205d60	60	return 1;
ce5aef0b MD	61	}
ce5aef0b MD	62
6715d7d1 MD	63	/*
	64	* Called under ust lock.
	65	*/
	66	static
	67	void lttng_lazy_probe_register(struct lttng_probe_desc *desc)
ce5aef0b	68	{
df854e41	69	struct lttng_probe_desc *iter;
ac69b35b	70	struct cds_list_head *probe_list;
48205d60	71
ce5aef0b	72	/*
48205d60 MD	73	* Each provider enforce that every event name begins with the
	74	* provider name. Check this in an assertion for extra
	75	* carefulness. This ensures we cannot have duplicate event
	76	* names across providers.
	77	*/
	78	assert(check_event_provider(desc));
	79
	80	/*
	81	* The provider ensures there are no duplicate event names.
	82	* Duplicated TRACEPOINT_EVENT event names would generate a
	83	* compile-time error due to duplicated symbol names.
ce5aef0b	84	*/
df854e41 MD	85
	86	/*
	87	* We sort the providers by struct lttng_probe_desc pointer
	88	* address.
	89	*/
6715d7d1	90	probe_list = &_probe_list;
ac69b35b	91	cds_list_for_each_entry_reverse(iter, probe_list, head) {
df854e41 MD	92	BUG_ON(iter == desc); /* Should never be in the list twice */
	93	if (iter < desc) {
	94	/* We belong to the location right after iter. */
	95	cds_list_add(&desc->head, &iter->head);
	96	goto desc_added;
	97	}
	98	}
	99	/* We should be added at the head of the list */
ac69b35b	100	cds_list_add(&desc->head, probe_list);
df854e41	101	desc_added:
e81a53af MD	102	DBG("just registered probe %s containing %u events",
e81a53af MD	103	desc->provider, desc->nr_events);
6715d7d1 MD	104	}
	105
	106	/*
	107	* Called under ust lock.
	108	*/
	109	static
	110	void fixup_lazy_probes(void)
	111	{
	112	struct lttng_probe_desc iter, tmp;
5f733922	113	int ret;
6715d7d1 MD	114
	115	lazy_nesting++;
	116	cds_list_for_each_entry_safe(iter, tmp,
	117	&lazy_probe_init, lazy_init_head) {
	118	lttng_lazy_probe_register(iter);
	119	iter->lazy = 0;
	120	cds_list_del(&iter->lazy_init_head);
	121	}
5f733922 MD	122	ret = lttng_fix_pending_events();
5f733922 MD	123	assert(!ret);
6715d7d1 MD	124	lazy_nesting--;
	125	}
	126
	127	/*
	128	* Called under ust lock.
	129	*/
	130	struct cds_list_head *lttng_get_probe_list_head(void)
	131	{
	132	if (!lazy_nesting && !cds_list_empty(&lazy_probe_init))
	133	fixup_lazy_probes();
	134	return &_probe_list;
	135	}
	136
71d31690 MD	137	static
	138	int check_provider_version(struct lttng_probe_desc *desc)
	139	{
	140	/*
	141	* Check tracepoint provider version compatibility.
	142	*/
	143	if (desc->major <= LTTNG_UST_PROVIDER_MAJOR) {
	144	DBG("Provider \"%s\" accepted, version %u.%u is compatible "
	145	"with LTTng UST provider version %u.%u.",
	146	desc->provider, desc->major, desc->minor,
	147	LTTNG_UST_PROVIDER_MAJOR,
	148	LTTNG_UST_PROVIDER_MINOR);
	149	if (desc->major < LTTNG_UST_PROVIDER_MAJOR) {
	150	DBG("However, some LTTng UST features might not be "
	151	"available for this provider unless it is "
	152	"recompiled against a more recent LTTng UST.");
	153	}
	154	return 1; /* accept */
	155	} else {
	156	ERR("Provider \"%s\" rejected, version %u.%u is incompatible "
	157	"with LTTng UST provider version %u.%u. Please upgrade "
	158	"LTTng UST.",
	159	desc->provider, desc->major, desc->minor,
	160	LTTNG_UST_PROVIDER_MAJOR,
	161	LTTNG_UST_PROVIDER_MINOR);
	162	return 0; /* reject */
	163	}
	164	}
	165
	166
6715d7d1 MD	167	int lttng_probe_register(struct lttng_probe_desc *desc)
	168	{
	169	int ret = 0;
	170
c362addf MD	171	lttng_ust_fixup_tls();
c362addf MD	172
71d31690 MD	173	/*
	174	* If version mismatch, don't register, but don't trigger assert
	175	* on caller. The version check just prints an error.
	176	*/
	177	if (!check_provider_version(desc))
	178	return 0;
	179
3327ac33	180	ust_lock_nocheck();
6715d7d1	181
6715d7d1 MD	182	cds_list_add(&desc->lazy_init_head, &lazy_probe_init);
	183	desc->lazy = 1;
	184	DBG("adding probe %s containing %u events to lazy registration list",
	185	desc->provider, desc->nr_events);
	186	/*
	187	* If there is at least one active session, we need to register
	188	* the probe immediately, since we cannot delay event
	189	* registration because they are needed ASAP.
	190	*/
	191	if (lttng_session_active())
	192	fixup_lazy_probes();
0fdd0b89	193
d8d2416d FD	194	lttng_fix_pending_event_notifiers();
d8d2416d FD	195
17dfb34b	196	ust_unlock();
ce5aef0b MD	197	return ret;
ce5aef0b MD	198	}
ce5aef0b	199
7dd08bec	200	void lttng_probe_unregister(struct lttng_probe_desc *desc)
ce5aef0b	201	{
c362addf MD	202	lttng_ust_fixup_tls();
c362addf MD	203
71d31690 MD	204	if (!check_provider_version(desc))
	205	return;
	206
3327ac33	207	ust_lock_nocheck();
6715d7d1 MD	208	if (!desc->lazy)
	209	cds_list_del(&desc->head);
	210	else
	211	cds_list_del(&desc->lazy_init_head);
2c05c691 FD	212
	213	lttng_probe_provider_unregister_events(desc);
	214	DBG("just unregistered probes of provider %s", desc->provider);
	215
17dfb34b	216	ust_unlock();
ce5aef0b	217	}
ce5aef0b	218
7dd08bec	219	void lttng_probes_prune_event_list(struct lttng_ust_tracepoint_list *list)
c8fcf224 MD	220	{
	221	struct tp_list_entry list_entry, tmp;
	222
	223	cds_list_for_each_entry_safe(list_entry, tmp, &list->head, head) {
	224	cds_list_del(&list_entry->head);
	225	free(list_entry);
	226	}
	227	}
	228
	229	/*
	230	* called with UST lock held.
	231	*/
7dd08bec	232	int lttng_probes_get_event_list(struct lttng_ust_tracepoint_list *list)
c8fcf224 MD	233	{
	234	struct lttng_probe_desc *probe_desc;
	235	int i;
ac69b35b	236	struct cds_list_head *probe_list;
c8fcf224	237
ac69b35b	238	probe_list = lttng_get_probe_list_head();
c8fcf224	239	CDS_INIT_LIST_HEAD(&list->head);
ac69b35b	240	cds_list_for_each_entry(probe_desc, probe_list, head) {
c8fcf224 MD	241	for (i = 0; i < probe_desc->nr_events; i++) {
	242	struct tp_list_entry *list_entry;
	243
	244	list_entry = zmalloc(sizeof(*list_entry));
	245	if (!list_entry)
	246	goto err_nomem;
	247	cds_list_add(&list_entry->head, &list->head);
	248	strncpy(list_entry->tp.name,
	249	probe_desc->event_desc[i]->name,
	250	LTTNG_UST_SYM_NAME_LEN);
	251	list_entry->tp.name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
	252	if (!probe_desc->event_desc[i]->loglevel) {
882a56d7	253	list_entry->tp.loglevel = TRACE_DEFAULT;
c8fcf224	254	} else {
882a56d7	255	list_entry->tp.loglevel = (probe_desc->event_desc[i]->loglevel);
c8fcf224 MD	256	}
	257	}
	258	}
	259	if (cds_list_empty(&list->head))
	260	list->iter = NULL;
	261	else
	262	list->iter =
	263	cds_list_first_entry(&list->head, struct tp_list_entry, head);
	264	return 0;
	265
	266	err_nomem:
7dd08bec	267	lttng_probes_prune_event_list(list);
c8fcf224 MD	268	return -ENOMEM;
	269	}
	270
	271	/*
	272	* Return current iteration position, advance internal iterator to next.
	273	* Return NULL if end of list.
	274	*/
	275	struct lttng_ust_tracepoint_iter *
	276	lttng_ust_tracepoint_list_get_iter_next(struct lttng_ust_tracepoint_list *list)
	277	{
	278	struct tp_list_entry *entry;
	279
	280	if (!list->iter)
	281	return NULL;
	282	entry = list->iter;
	283	if (entry->head.next == &list->head)
	284	list->iter = NULL;
	285	else
	286	list->iter = cds_list_entry(entry->head.next,
	287	struct tp_list_entry, head);
	288	return &entry->tp;
	289	}
1f18504e	290
7dd08bec	291	void lttng_probes_prune_field_list(struct lttng_ust_field_list *list)
06d4f27e MD	292	{
	293	struct tp_field_list_entry list_entry, tmp;
	294
	295	cds_list_for_each_entry_safe(list_entry, tmp, &list->head, head) {
	296	cds_list_del(&list_entry->head);
	297	free(list_entry);
	298	}
	299	}
	300
	301	/*
	302	* called with UST lock held.
	303	*/
7dd08bec	304	int lttng_probes_get_field_list(struct lttng_ust_field_list *list)
06d4f27e MD	305	{
	306	struct lttng_probe_desc *probe_desc;
	307	int i;
ac69b35b	308	struct cds_list_head *probe_list;
06d4f27e	309
ac69b35b	310	probe_list = lttng_get_probe_list_head();
06d4f27e	311	CDS_INIT_LIST_HEAD(&list->head);
ac69b35b	312	cds_list_for_each_entry(probe_desc, probe_list, head) {
06d4f27e MD	313	for (i = 0; i < probe_desc->nr_events; i++) {
	314	const struct lttng_event_desc *event_desc =
	315	probe_desc->event_desc[i];
	316	int j;
	317
26329f26 MD	318	if (event_desc->nr_fields == 0) {
	319	/* Events without fields. */
	320	struct tp_field_list_entry *list_entry;
	321
	322	list_entry = zmalloc(sizeof(*list_entry));
	323	if (!list_entry)
	324	goto err_nomem;
	325	cds_list_add(&list_entry->head, &list->head);
	326	strncpy(list_entry->field.event_name,
	327	event_desc->name,
	328	LTTNG_UST_SYM_NAME_LEN);
	329	list_entry->field.event_name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
	330	list_entry->field.field_name[0] = '\0';
	331	list_entry->field.type = LTTNG_UST_FIELD_OTHER;
	332	if (!event_desc->loglevel) {
	333	list_entry->field.loglevel = TRACE_DEFAULT;
	334	} else {
	335	list_entry->field.loglevel = (event_desc->loglevel);
	336	}
	337	list_entry->field.nowrite = 1;
	338	}
	339
06d4f27e MD	340	for (j = 0; j < event_desc->nr_fields; j++) {
	341	const struct lttng_event_field *event_field =
	342	&event_desc->fields[j];
	343	struct tp_field_list_entry *list_entry;
	344
	345	list_entry = zmalloc(sizeof(*list_entry));
	346	if (!list_entry)
	347	goto err_nomem;
	348	cds_list_add(&list_entry->head, &list->head);
	349	strncpy(list_entry->field.event_name,
	350	event_desc->name,
	351	LTTNG_UST_SYM_NAME_LEN);
	352	list_entry->field.event_name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
	353	strncpy(list_entry->field.field_name,
	354	event_field->name,
	355	LTTNG_UST_SYM_NAME_LEN);
	356	list_entry->field.field_name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
40003310 MD	357	switch (event_field->type.atype) {
	358	case atype_integer:
	359	list_entry->field.type = LTTNG_UST_FIELD_INTEGER;
	360	break;
	361	case atype_string:
	362	list_entry->field.type = LTTNG_UST_FIELD_STRING;
	363	break;
	364	case atype_array:
218deb69 MD	365	if (event_field->type.u.legacy.array.elem_type.atype != atype_integer
	366	\|\| event_field->type.u.legacy.array.elem_type.u.basic.integer.encoding == lttng_encode_none)
	367	list_entry->field.type = LTTNG_UST_FIELD_OTHER;
	368	else
	369	list_entry->field.type = LTTNG_UST_FIELD_STRING;
	370	break;
	371	case atype_array_nestable:
	372	if (event_field->type.u.array_nestable.elem_type->atype != atype_integer
	373	\|\| event_field->type.u.array_nestable.elem_type->u.integer.encoding == lttng_encode_none)
40003310 MD	374	list_entry->field.type = LTTNG_UST_FIELD_OTHER;
	375	else
	376	list_entry->field.type = LTTNG_UST_FIELD_STRING;
	377	break;
	378	case atype_sequence:
218deb69 MD	379	if (event_field->type.u.legacy.sequence.elem_type.atype != atype_integer
	380	\|\| event_field->type.u.legacy.sequence.elem_type.u.basic.integer.encoding == lttng_encode_none)
	381	list_entry->field.type = LTTNG_UST_FIELD_OTHER;
	382	else
	383	list_entry->field.type = LTTNG_UST_FIELD_STRING;
	384	break;
	385	case atype_sequence_nestable:
	386	if (event_field->type.u.sequence_nestable.elem_type->atype != atype_integer
	387	\|\| event_field->type.u.sequence_nestable.elem_type->u.integer.encoding == lttng_encode_none)
40003310 MD	388	list_entry->field.type = LTTNG_UST_FIELD_OTHER;
	389	else
	390	list_entry->field.type = LTTNG_UST_FIELD_STRING;
	391	break;
	392	case atype_float:
	393	list_entry->field.type = LTTNG_UST_FIELD_FLOAT;
	394	break;
218deb69 MD	395	case atype_enum: /* Fall-through */
218deb69 MD	396	case atype_enum_nestable:
40003310 MD	397	list_entry->field.type = LTTNG_UST_FIELD_ENUM;
	398	break;
	399	default:
	400	list_entry->field.type = LTTNG_UST_FIELD_OTHER;
	401	}
06d4f27e MD	402	if (!event_desc->loglevel) {
	403	list_entry->field.loglevel = TRACE_DEFAULT;
	404	} else {
	405	list_entry->field.loglevel = (event_desc->loglevel);
	406	}
180901e6	407	list_entry->field.nowrite = event_field->nowrite;
06d4f27e MD	408	}
	409	}
	410	}
	411	if (cds_list_empty(&list->head))
	412	list->iter = NULL;
	413	else
	414	list->iter =
	415	cds_list_first_entry(&list->head,
	416	struct tp_field_list_entry, head);
	417	return 0;
	418
	419	err_nomem:
7dd08bec	420	lttng_probes_prune_field_list(list);
06d4f27e MD	421	return -ENOMEM;
	422	}
	423
	424	/*
	425	* Return current iteration position, advance internal iterator to next.
	426	* Return NULL if end of list.
	427	*/
	428	struct lttng_ust_field_iter *
	429	lttng_ust_field_list_get_iter_next(struct lttng_ust_field_list *list)
	430	{
	431	struct tp_field_list_entry *entry;
	432
	433	if (!list->iter)
	434	return NULL;
	435	entry = list->iter;
	436	if (entry->head.next == &list->head)
	437	list->iter = NULL;
	438	else
	439	list->iter = cds_list_entry(entry->head.next,
	440	struct tp_field_list_entry, head);
	441	return &entry->field;
	442	}