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

/*
 * ltt-probes.c
 *
 * Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * Holds LTTng probes registry.
 *
 * Dual LGPL v2.1/GPL v2 license.
 */

#include <string.h>
#include <errno.h>
#include <urcu/list.h>
#include <urcu/hlist.h>
#include <lttng/ust-events.h>
#include <assert.h>
#include <helper.h>
#include <ctype.h>

#include "ltt-tracer-core.h"
#include "jhash.h"
#include "error.h"

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

/*
 * Loglevel hash table, containing the active loglevels.
 * Protected by ust lock.
 */
#define LOGLEVEL_HASH_BITS 6
#define LOGLEVEL_TABLE_SIZE (1 << LOGLEVEL_HASH_BITS)
static struct cds_hlist_head loglevel_table[LOGLEVEL_TABLE_SIZE];

/*
 * Wildcard list, containing the active wildcards.
 * Protected by ust lock.
 */
static CDS_LIST_HEAD(wildcard_list);

static
const struct lttng_probe_desc *find_provider(const char *provider)
{
	struct lttng_probe_desc *iter;

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

static
const struct lttng_event_desc *find_event(const char *name)
{
	struct lttng_probe_desc *probe_desc;
	int i;

	cds_list_for_each_entry(probe_desc, &probe_list, head) {
		for (i = 0; i < probe_desc->nr_events; i++) {
			if (!strncmp(probe_desc->event_desc[i]->name, name,
					LTTNG_UST_SYM_NAME_LEN - 1))
				return probe_desc->event_desc[i];
		}
	}
	return NULL;
}

int ltt_probe_register(struct lttng_probe_desc *desc)
{
	struct lttng_probe_desc *iter;
	int ret = 0;
	int i;

	ust_lock();
	if (find_provider(desc->provider)) {
		ret = -EEXIST;
		goto end;
	}
	/*
	 * TODO: This is O(N^2). Turn into a hash table when probe registration
	 * overhead becomes an issue.
	 */
	for (i = 0; i < desc->nr_events; i++) {
		if (find_event(desc->event_desc[i]->name)) {
			ret = -EEXIST;
			goto end;
		}
	}

	/*
	 * We sort the providers by struct lttng_probe_desc pointer
	 * address.
	 */
	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:

	/*
	 * fix the events awaiting probe load.
	 */
	for (i = 0; i < desc->nr_events; i++) {
		ret = pending_probe_fix_events(desc->event_desc[i]);
		assert(!ret);
	}
end:
	ust_unlock();
	return ret;
}

void ltt_probe_unregister(struct lttng_probe_desc *desc)
{
	ust_lock();
	cds_list_del(&desc->head);
	ust_unlock();
}

/*
 * called with UST lock held.
 */
const struct lttng_event_desc *ltt_event_get(const char *name)
{
	const struct lttng_event_desc *event;

	event = find_event(name);
	if (!event)
		return NULL;
	return event;
}

void ltt_event_put(const struct lttng_event_desc *event)
{
}

void ltt_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 ltt_probes_get_event_list(struct lttng_ust_tracepoint_list *list)
{
	struct lttng_probe_desc *probe_desc;
	int i;

	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[0] = '\0';
				list_entry->tp.loglevel_value = 0;
			} else {
				strncpy(list_entry->tp.loglevel,
					(*probe_desc->event_desc[i]->loglevel)->identifier,
					LTTNG_UST_SYM_NAME_LEN);
				list_entry->tp.loglevel[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
				list_entry->tp.loglevel_value =
					(*probe_desc->event_desc[i]->loglevel)->value;
			}
		}
	}
	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:
	ltt_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;
}

/*
 * Get loglevel if the loglevel is present in the loglevel hash table.
 * Must be called with ust lock held.
 * Returns NULL if not present.
 */
struct loglevel_entry *get_loglevel(const char *name)
{
	struct cds_hlist_head *head;
	struct cds_hlist_node *node;
	struct loglevel_entry *e;
	size_t name_len = strlen(name);
	uint32_t hash;

	if (name_len > LTTNG_UST_SYM_NAME_LEN - 1) {
		WARN("Truncating loglevel name %s which exceeds size limits of %u chars", name, LTTNG_UST_SYM_NAME_LEN - 1);
		name_len = LTTNG_UST_SYM_NAME_LEN - 1;
	}
	hash = jhash(name, name_len, 0);
	head = &loglevel_table[hash & (LOGLEVEL_TABLE_SIZE - 1)];
	cds_hlist_for_each_entry(e, node, head, hlist) {
		if (!strncmp(name, e->name, LTTNG_UST_SYM_NAME_LEN - 1))
			return e;
	}
	return NULL;
}

struct loglevel_entry *get_loglevel_value(int64_t value)
{
	char name[LTTNG_UST_SYM_NAME_LEN];
	int ret;

	ret = snprintf(name, LTTNG_UST_SYM_NAME_LEN, "%lld", (long long) value);
	if (ret < 0)
		return NULL;
	return get_loglevel(name);
}

/*
 * marshall all probes/all events and create those that fit the
 * loglevel. Add them to the events list as created.
 */
static
void _probes_create_loglevel_events(struct loglevel_entry *entry,
				struct session_loglevel *loglevel)
{
	struct lttng_probe_desc *probe_desc;
	struct lttng_ust_event event_param;
	int i;

	cds_list_for_each_entry(probe_desc, &probe_list, head) {
		for (i = 0; i < probe_desc->nr_events; i++) {
			const struct tracepoint_loglevel_entry *ev_ll;
			const struct lttng_event_desc *event_desc;
			int match = 0;

			event_desc = probe_desc->event_desc[i];
			if (!(event_desc->loglevel))
				continue;
			ev_ll = *event_desc->loglevel;
			if (isdigit(entry->name[0])) {
				if (atoll(entry->name) == ev_ll->value) {
					match = 1;
				}
			} else if (!strncmp(ev_ll->identifier, entry->name,
					LTTNG_UST_SYM_NAME_LEN - 1)) {
				match = 1;
			}

			if (match) {
				struct ltt_event *ev;
				int ret;

				memcpy(&event_param, &loglevel->event_param,
						sizeof(event_param));
				memcpy(event_param.name,
					event_desc->name,
					sizeof(event_param.name));
				/* create event */
				ret = ltt_event_create(loglevel->chan,
					&event_param, NULL,
					&ev);
				if (ret) {
					DBG("Error creating event");
					continue;
				}
				cds_list_add(&ev->loglevel_list,
					&loglevel->events);
			}
		}
	}
}

/*
 * Add the loglevel to the loglevel hash table. Must be called with
 * ust lock held.
 */
struct session_loglevel *add_loglevel(const char *name,
	struct ltt_channel *chan,
	struct lttng_ust_event *event_param)
{
	struct cds_hlist_head *head;
	struct cds_hlist_node *node;
	struct loglevel_entry *e;
	struct session_loglevel *sl;
	int found = 0;
	size_t name_len = strlen(name);
	uint32_t hash;

	if (name_len > LTTNG_UST_SYM_NAME_LEN - 1) {
		WARN("Truncating loglevel name %s which exceeds size limits of %u chars", name, LTTNG_UST_SYM_NAME_LEN - 1);
		name_len = LTTNG_UST_SYM_NAME_LEN - 1;
	}
	hash = jhash(name, name_len, 0);
	/* loglevel entry */
	head = &loglevel_table[hash & (LOGLEVEL_TABLE_SIZE - 1)];
	cds_hlist_for_each_entry(e, node, head, hlist) {
		if (!strncmp(name, e->name, LTTNG_UST_SYM_NAME_LEN - 1)) {
			found = 1;
			break;
		}
	}

	if (!found) {
		/*
		 * Using zmalloc here to allocate a variable length element. Could
		 * cause some memory fragmentation if overused.
		 */
		e = zmalloc(sizeof(struct loglevel_entry) + name_len + 1);
		if (!e)
			return ERR_PTR(-ENOMEM);
		memcpy(&e->name[0], name, name_len + 1);
		e->name[name_len] = '\0';
		cds_hlist_add_head(&e->hlist, head);
		CDS_INIT_LIST_HEAD(&e->session_list);
	}

	/* session loglevel */
	cds_list_for_each_entry(sl, &e->session_list, session_list) {
		if (chan == sl->chan) {
			DBG("loglevel %s busy for this channel", name);
			return ERR_PTR(-EEXIST);	/* Already there */
		}
	}
	sl = zmalloc(sizeof(struct session_loglevel));
	if (!sl)
		return ERR_PTR(-ENOMEM);
	sl->chan = chan;
	sl->enabled = 1;
	memcpy(&sl->event_param, event_param, sizeof(sl->event_param));
	sl->event_param.instrumentation = LTTNG_UST_TRACEPOINT;
	CDS_INIT_LIST_HEAD(&sl->events);
	cds_list_add(&sl->list, &chan->session->loglevels);
	cds_list_add(&sl->session_list, &e->session_list);
	sl->entry = e;
	_probes_create_loglevel_events(e, sl);
	return sl;
}

/*
 * Remove the loglevel from the loglevel hash table. Must be called with
 * ust_lock held. Only called at session teardown.
 */
void _remove_loglevel(struct session_loglevel *loglevel)
{
	struct ltt_event *ev, *tmp;

	/*
	 * Just remove the events owned (for enable/disable) by this
	 * loglevel from the list. The session teardown will take care
	 * of freeing the event memory.
	 */
	cds_list_for_each_entry_safe(ev, tmp, &loglevel->events,
			loglevel_list) {
		cds_list_del(&ev->loglevel_list);
	}
	cds_list_del(&loglevel->session_list);
	cds_list_del(&loglevel->list);
	if (cds_list_empty(&loglevel->entry->session_list)) {
		cds_hlist_del(&loglevel->entry->hlist);
		free(loglevel->entry);
	}
	free(loglevel);
}

int ltt_loglevel_enable(struct session_loglevel *loglevel)
{
	struct ltt_event *ev;
	int ret;

	if (loglevel->enabled)
		return -EEXIST;
	cds_list_for_each_entry(ev, &loglevel->events, loglevel_list) {
		ret = ltt_event_enable(ev);
		if (ret) {
			DBG("Error: enable error.\n");
			return ret;
		}
	}
	loglevel->enabled = 1;
	return 0;
}

int ltt_loglevel_disable(struct session_loglevel *loglevel)
{
	struct ltt_event *ev;
	int ret;

	if (!loglevel->enabled)
		return -EEXIST;
	cds_list_for_each_entry(ev, &loglevel->events, loglevel_list) {
		ret = ltt_event_disable(ev);
		if (ret) {
			DBG("Error: disable error.\n");
			return ret;
		}
	}
	loglevel->enabled = 0;
	return 0;
}

/* WILDCARDS */

/*
 * Return wildcard for a given event name if the event name match the
 * one of the wildcards.
 * Must be called with ust lock held.
 * Returns NULL if not present.
 */
struct wildcard_entry *match_wildcard(const char *name)
{
	struct wildcard_entry *e;

	cds_list_for_each_entry(e, &wildcard_list, list) {
		/* If only contain '*' */
		if (strlen(e->name) == 1)
			return e;
		/* Compare excluding final '*' */
		if (!strncmp(name, e->name, strlen(e->name) - 1))
			return e;
	}
	return NULL;
}

/*
 * marshall all probes/all events and create those that fit the
 * wildcard. Add them to the events list as created.
 */
static
void _probes_create_wildcard_events(struct wildcard_entry *entry,
				struct session_wildcard *wildcard)
{
	struct lttng_probe_desc *probe_desc;
	struct lttng_ust_event event_param;
	int i;

	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;
			int match = 0;

			event_desc = probe_desc->event_desc[i];
			/* compare excluding final '*' */
			assert(strlen(entry->name) > 0);
			if (strcmp(event_desc->name, "lttng_ust:metadata")
					&& (strlen(entry->name) == 1
						|| !strncmp(event_desc->name, entry->name,
							strlen(entry->name) - 1))) {
				match = 1;
			}
			if (match) {
				struct ltt_event *ev;
				int ret;

				memcpy(&event_param, &wildcard->event_param,
						sizeof(event_param));
				memcpy(event_param.name,
					event_desc->name,
					sizeof(event_param.name));
				/* create event */
				ret = ltt_event_create(wildcard->chan,
					&event_param, NULL,
					&ev);
				if (ret) {
					DBG("Error creating event");
					continue;
				}
				cds_list_add(&ev->wildcard_list,
					&wildcard->events);
			}
		}
	}
}

/*
 * Add the wildcard to the wildcard hash table. Must be called with
 * ust lock held.
 */
struct session_wildcard *add_wildcard(const char *name,
	struct ltt_channel *chan,
	struct lttng_ust_event *event_param)
{
	struct wildcard_entry *e;
	struct session_wildcard *sw;
	size_t name_len = strlen(name) + 1;
	int found = 0;

	/* wildcard entry */
	cds_list_for_each_entry(e, &wildcard_list, list) {
		if (!strncmp(name, e->name, LTTNG_UST_SYM_NAME_LEN - 1)) {
			found = 1;
			break;
		}
	}

	if (!found) {
		/*
		 * Using zmalloc here to allocate a variable length element. Could
		 * cause some memory fragmentation if overused.
		 */
		e = zmalloc(sizeof(struct wildcard_entry) + name_len);
		if (!e)
			return ERR_PTR(-ENOMEM);
		memcpy(&e->name[0], name, name_len);
		cds_list_add(&e->list, &wildcard_list);
		CDS_INIT_LIST_HEAD(&e->session_list);
	}

	/* session wildcard */
	cds_list_for_each_entry(sw, &e->session_list, session_list) {
		if (chan == sw->chan) {
			DBG("wildcard %s busy for this channel", name);
			return ERR_PTR(-EEXIST);	/* Already there */
		}
	}
	sw = zmalloc(sizeof(struct session_wildcard));
	if (!sw)
		return ERR_PTR(-ENOMEM);
	sw->chan = chan;
	sw->enabled = 1;
	memcpy(&sw->event_param, event_param, sizeof(sw->event_param));
	sw->event_param.instrumentation = LTTNG_UST_TRACEPOINT;
	CDS_INIT_LIST_HEAD(&sw->events);
	cds_list_add(&sw->list, &chan->session->wildcards);
	cds_list_add(&sw->session_list, &e->session_list);
	sw->entry = e;
	_probes_create_wildcard_events(e, sw);
	return sw;
}

/*
 * Remove the wildcard from the wildcard hash table. Must be called with
 * ust_lock held. Only called at session teardown.
 */
void _remove_wildcard(struct session_wildcard *wildcard)
{
	struct ltt_event *ev, *tmp;

	/*
	 * Just remove the events owned (for enable/disable) by this
	 * wildcard from the list. The session teardown will take care
	 * of freeing the event memory.
	 */
	cds_list_for_each_entry_safe(ev, tmp, &wildcard->events,
			wildcard_list) {
		cds_list_del(&ev->wildcard_list);
	}
	cds_list_del(&wildcard->session_list);
	cds_list_del(&wildcard->list);
	if (cds_list_empty(&wildcard->entry->session_list)) {
		cds_list_del(&wildcard->entry->list);
		free(wildcard->entry);
	}
	free(wildcard);
}

int ltt_wildcard_enable(struct session_wildcard *wildcard)
{
	struct ltt_event *ev;
	int ret;

	if (wildcard->enabled)
		return -EEXIST;
	cds_list_for_each_entry(ev, &wildcard->events, wildcard_list) {
		ret = ltt_event_enable(ev);
		if (ret) {
			DBG("Error: enable error.\n");
			return ret;
		}
	}
	wildcard->enabled = 1;
	return 0;
}

int ltt_wildcard_disable(struct session_wildcard *wildcard)
{
	struct ltt_event *ev;
	int ret;

	if (!wildcard->enabled)
		return -EEXIST;
	cds_list_for_each_entry(ev, &wildcard->events, wildcard_list) {
		ret = ltt_event_disable(ev);
		if (ret) {
			DBG("Error: disable error.\n");
			return ret;
		}
	}
	wildcard->enabled = 0;
	return 0;
}
Commit	Line	Data
ce5aef0b MD	1	/*
	2	* ltt-probes.c
	3	*
	4	* Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	5	*
	6	* Holds LTTng probes registry.
	7	*
	8	* Dual LGPL v2.1/GPL v2 license.
	9	*/
	10
8d8a24c8 MD	11	#include <string.h>
	12	#include <errno.h>
	13	#include <urcu/list.h>
1f18504e	14	#include <urcu/hlist.h>
4318ae1b	15	#include <lttng/ust-events.h>
a3bb4b27	16	#include <assert.h>
c8fcf224	17	#include <helper.h>
48740cab	18	#include <ctype.h>
ce5aef0b	19
8165c8da	20	#include "ltt-tracer-core.h"
1f18504e MD	21	#include "jhash.h"
1f18504e MD	22	#include "error.h"
8165c8da MD	23
8165c8da MD	24	/*
17dfb34b	25	* probe list is protected by ust_lock()/ust_unlock().
8165c8da	26	*/
8d8a24c8	27	static CDS_LIST_HEAD(probe_list);
ce5aef0b	28
1f18504e MD	29	/*
	30	* Loglevel hash table, containing the active loglevels.
	31	* Protected by ust lock.
	32	*/
	33	#define LOGLEVEL_HASH_BITS 6
	34	#define LOGLEVEL_TABLE_SIZE (1 << LOGLEVEL_HASH_BITS)
	35	static struct cds_hlist_head loglevel_table[LOGLEVEL_TABLE_SIZE];
	36
e6c12e3d MD	37	/*
	38	* Wildcard list, containing the active wildcards.
	39	* Protected by ust lock.
	40	*/
	41	static CDS_LIST_HEAD(wildcard_list);
	42
df854e41 MD	43	static
	44	const struct lttng_probe_desc find_provider(const char provider)
	45	{
	46	struct lttng_probe_desc *iter;
	47
	48	cds_list_for_each_entry(iter, &probe_list, head) {
	49	if (!strcmp(iter->provider, provider))
	50	return iter;
	51	}
	52	return NULL;
	53	}
	54
ce5aef0b MD	55	static
	56	const struct lttng_event_desc find_event(const char name)
	57	{
	58	struct lttng_probe_desc *probe_desc;
	59	int i;
	60
8d8a24c8	61	cds_list_for_each_entry(probe_desc, &probe_list, head) {
ce5aef0b	62	for (i = 0; i < probe_desc->nr_events; i++) {
ff412fb5 MD	63	if (!strncmp(probe_desc->event_desc[i]->name, name,
ff412fb5 MD	64	LTTNG_UST_SYM_NAME_LEN - 1))
df854e41	65	return probe_desc->event_desc[i];
ce5aef0b MD	66	}
	67	}
	68	return NULL;
	69	}
	70
	71	int ltt_probe_register(struct lttng_probe_desc *desc)
	72	{
df854e41	73	struct lttng_probe_desc *iter;
ce5aef0b MD	74	int ret = 0;
	75	int i;
	76
17dfb34b	77	ust_lock();
df854e41 MD	78	if (find_provider(desc->provider)) {
	79	ret = -EEXIST;
	80	goto end;
	81	}
ce5aef0b MD	82	/*
	83	* TODO: This is O(N^2). Turn into a hash table when probe registration
	84	* overhead becomes an issue.
	85	*/
	86	for (i = 0; i < desc->nr_events; i++) {
df854e41	87	if (find_event(desc->event_desc[i]->name)) {
ce5aef0b MD	88	ret = -EEXIST;
	89	goto end;
	90	}
	91	}
df854e41 MD	92
	93	/*
	94	* We sort the providers by struct lttng_probe_desc pointer
	95	* address.
	96	*/
	97	cds_list_for_each_entry_reverse(iter, &probe_list, head) {
	98	BUG_ON(iter == desc); /* Should never be in the list twice */
	99	if (iter < desc) {
	100	/* We belong to the location right after iter. */
	101	cds_list_add(&desc->head, &iter->head);
	102	goto desc_added;
	103	}
	104	}
	105	/* We should be added at the head of the list */
8d8a24c8	106	cds_list_add(&desc->head, &probe_list);
df854e41	107	desc_added:
8165c8da MD	108
	109	/*
	110	* fix the events awaiting probe load.
	111	*/
	112	for (i = 0; i < desc->nr_events; i++) {
df854e41	113	ret = pending_probe_fix_events(desc->event_desc[i]);
8165c8da MD	114	assert(!ret);
8165c8da MD	115	}
ce5aef0b	116	end:
17dfb34b	117	ust_unlock();
ce5aef0b MD	118	return ret;
ce5aef0b MD	119	}
ce5aef0b MD	120
	121	void ltt_probe_unregister(struct lttng_probe_desc *desc)
	122	{
17dfb34b	123	ust_lock();
8d8a24c8	124	cds_list_del(&desc->head);
17dfb34b	125	ust_unlock();
ce5aef0b	126	}
ce5aef0b	127
8165c8da MD	128	/*
	129	* called with UST lock held.
	130	*/
ce5aef0b MD	131	const struct lttng_event_desc ltt_event_get(const char name)
	132	{
	133	const struct lttng_event_desc *event;
ce5aef0b	134
ce5aef0b	135	event = find_event(name);
ce5aef0b MD	136	if (!event)
ce5aef0b MD	137	return NULL;
ce5aef0b MD	138	return event;
ce5aef0b MD	139	}
ce5aef0b MD	140
	141	void ltt_event_put(const struct lttng_event_desc *event)
	142	{
ce5aef0b	143	}
c8fcf224 MD	144
	145	void ltt_probes_prune_event_list(struct lttng_ust_tracepoint_list *list)
	146	{
	147	struct tp_list_entry list_entry, tmp;
	148
	149	cds_list_for_each_entry_safe(list_entry, tmp, &list->head, head) {
	150	cds_list_del(&list_entry->head);
	151	free(list_entry);
	152	}
	153	}
	154
	155	/*
	156	* called with UST lock held.
	157	*/
	158	int ltt_probes_get_event_list(struct lttng_ust_tracepoint_list *list)
	159	{
	160	struct lttng_probe_desc *probe_desc;
	161	int i;
	162
	163	CDS_INIT_LIST_HEAD(&list->head);
	164	cds_list_for_each_entry(probe_desc, &probe_list, head) {
	165	for (i = 0; i < probe_desc->nr_events; i++) {
	166	struct tp_list_entry *list_entry;
	167
	168	list_entry = zmalloc(sizeof(*list_entry));
	169	if (!list_entry)
	170	goto err_nomem;
	171	cds_list_add(&list_entry->head, &list->head);
	172	strncpy(list_entry->tp.name,
	173	probe_desc->event_desc[i]->name,
	174	LTTNG_UST_SYM_NAME_LEN);
	175	list_entry->tp.name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
	176	if (!probe_desc->event_desc[i]->loglevel) {
	177	list_entry->tp.loglevel[0] = '\0';
	178	list_entry->tp.loglevel_value = 0;
	179	} else {
	180	strncpy(list_entry->tp.loglevel,
	181	(*probe_desc->event_desc[i]->loglevel)->identifier,
	182	LTTNG_UST_SYM_NAME_LEN);
	183	list_entry->tp.loglevel[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
	184	list_entry->tp.loglevel_value =
	185	(*probe_desc->event_desc[i]->loglevel)->value;
	186	}
	187	}
	188	}
	189	if (cds_list_empty(&list->head))
	190	list->iter = NULL;
	191	else
	192	list->iter =
	193	cds_list_first_entry(&list->head, struct tp_list_entry, head);
	194	return 0;
	195
	196	err_nomem:
	197	ltt_probes_prune_event_list(list);
	198	return -ENOMEM;
	199	}
	200
	201	/*
	202	* Return current iteration position, advance internal iterator to next.
	203	* Return NULL if end of list.
	204	*/
	205	struct lttng_ust_tracepoint_iter *
	206	lttng_ust_tracepoint_list_get_iter_next(struct lttng_ust_tracepoint_list *list)
	207	{
208	struct tp_list_entry *entry;
209
210	if (!list->iter)
211	return NULL;
212	entry = list->iter;
213	if (entry->head.next == &list->head)
214	list->iter = NULL;
215	else
216	list->iter = cds_list_entry(entry->head.next,
217	struct tp_list_entry, head);
218	return &entry->tp;
219	}
1f18504e MD	220
	221	/*
	222	* Get loglevel if the loglevel is present in the loglevel hash table.
	223	* Must be called with ust lock held.
	224	* Returns NULL if not present.
	225	*/
	226	struct loglevel_entry get_loglevel(const char name)
	227	{
	228	struct cds_hlist_head *head;
	229	struct cds_hlist_node *node;
	230	struct loglevel_entry *e;
ff412fb5 MD	231	size_t name_len = strlen(name);
ff412fb5 MD	232	uint32_t hash;
1f18504e	233
ff412fb5 MD	234	if (name_len > LTTNG_UST_SYM_NAME_LEN - 1) {
	235	WARN("Truncating loglevel name %s which exceeds size limits of %u chars", name, LTTNG_UST_SYM_NAME_LEN - 1);
	236	name_len = LTTNG_UST_SYM_NAME_LEN - 1;
	237	}
	238	hash = jhash(name, name_len, 0);
1f18504e MD	239	head = &loglevel_table[hash & (LOGLEVEL_TABLE_SIZE - 1)];
1f18504e MD	240	cds_hlist_for_each_entry(e, node, head, hlist) {
ff412fb5	241	if (!strncmp(name, e->name, LTTNG_UST_SYM_NAME_LEN - 1))
1f18504e MD	242	return e;
	243	}
	244	return NULL;
	245	}
	246
48740cab MD	247	struct loglevel_entry *get_loglevel_value(int64_t value)
	248	{
	249	char name[LTTNG_UST_SYM_NAME_LEN];
	250	int ret;
	251
	252	ret = snprintf(name, LTTNG_UST_SYM_NAME_LEN, "%lld", (long long) value);
	253	if (ret < 0)
	254	return NULL;
	255	return get_loglevel(name);
	256	}
	257
1f18504e MD	258	/*
	259	* marshall all probes/all events and create those that fit the
	260	* loglevel. Add them to the events list as created.
	261	*/
	262	static
574a6217 MD	263	void _probes_create_loglevel_events(struct loglevel_entry *entry,
574a6217 MD	264	struct session_loglevel *loglevel)
1f18504e MD	265	{
1f18504e MD	266	struct lttng_probe_desc *probe_desc;
7ee3cc56	267	struct lttng_ust_event event_param;
1f18504e MD	268	int i;
	269
	270	cds_list_for_each_entry(probe_desc, &probe_list, head) {
	271	for (i = 0; i < probe_desc->nr_events; i++) {
	272	const struct tracepoint_loglevel_entry *ev_ll;
7ee3cc56	273	const struct lttng_event_desc *event_desc;
5e87eb4a	274	int match = 0;
1f18504e	275
7ee3cc56 MD	276	event_desc = probe_desc->event_desc[i];
7ee3cc56 MD	277	if (!(event_desc->loglevel))
1f18504e	278	continue;
7ee3cc56	279	ev_ll = *event_desc->loglevel;
3431ca3e	280	if (isdigit(entry->name[0])) {
48740cab MD	281	if (atoll(entry->name) == ev_ll->value) {
	282	match = 1;
	283	}
ff412fb5 MD	284	} else if (!strncmp(ev_ll->identifier, entry->name,
ff412fb5 MD	285	LTTNG_UST_SYM_NAME_LEN - 1)) {
48740cab MD	286	match = 1;
	287	}
	288
	289	if (match) {
1f18504e MD	290	struct ltt_event *ev;
	291	int ret;
	292
7ee3cc56 MD	293	memcpy(&event_param, &loglevel->event_param,
	294	sizeof(event_param));
	295	memcpy(event_param.name,
	296	event_desc->name,
	297	sizeof(event_param.name));
1f18504e MD	298	/* create event */
1f18504e MD	299	ret = ltt_event_create(loglevel->chan,
7ee3cc56	300	&event_param, NULL,
1f18504e	301	&ev);
7ee3cc56 MD	302	if (ret) {
7ee3cc56 MD	303	DBG("Error creating event");
1f18504e	304	continue;
7ee3cc56	305	}
1f18504e MD	306	cds_list_add(&ev->loglevel_list,
	307	&loglevel->events);
	308	}
1f18504e MD	309	}
	310	}
	311	}
	312
	313	/*
	314	* Add the loglevel to the loglevel hash table. Must be called with
	315	* ust lock held.
	316	*/
574a6217	317	struct session_loglevel add_loglevel(const char name,
1f18504e MD	318	struct ltt_channel *chan,
	319	struct lttng_ust_event *event_param)
	320	{
	321	struct cds_hlist_head *head;
	322	struct cds_hlist_node *node;
	323	struct loglevel_entry *e;
574a6217	324	struct session_loglevel *sl;
574a6217	325	int found = 0;
ff412fb5 MD	326	size_t name_len = strlen(name);
ff412fb5 MD	327	uint32_t hash;
1f18504e	328
ff412fb5 MD	329	if (name_len > LTTNG_UST_SYM_NAME_LEN - 1) {
	330	WARN("Truncating loglevel name %s which exceeds size limits of %u chars", name, LTTNG_UST_SYM_NAME_LEN - 1);
	331	name_len = LTTNG_UST_SYM_NAME_LEN - 1;
	332	}
	333	hash = jhash(name, name_len, 0);
574a6217	334	/* loglevel entry */
1f18504e MD	335	head = &loglevel_table[hash & (LOGLEVEL_TABLE_SIZE - 1)];
1f18504e MD	336	cds_hlist_for_each_entry(e, node, head, hlist) {
ff412fb5	337	if (!strncmp(name, e->name, LTTNG_UST_SYM_NAME_LEN - 1)) {
574a6217 MD	338	found = 1;
	339	break;
	340	}
	341	}
	342
	343	if (!found) {
	344	/*
	345	* Using zmalloc here to allocate a variable length element. Could
	346	* cause some memory fragmentation if overused.
	347	*/
ff412fb5	348	e = zmalloc(sizeof(struct loglevel_entry) + name_len + 1);
574a6217 MD	349	if (!e)
574a6217 MD	350	return ERR_PTR(-ENOMEM);
ff412fb5 MD	351	memcpy(&e->name[0], name, name_len + 1);
ff412fb5 MD	352	e->name[name_len] = '\0';
574a6217	353	cds_hlist_add_head(&e->hlist, head);
d5201d38	354	CDS_INIT_LIST_HEAD(&e->session_list);
574a6217 MD	355	}
	356
	357	/* session loglevel */
	358	cds_list_for_each_entry(sl, &e->session_list, session_list) {
	359	if (chan == sl->chan) {
	360	DBG("loglevel %s busy for this channel", name);
1f18504e MD	361	return ERR_PTR(-EEXIST); /* Already there */
	362	}
	363	}
574a6217 MD	364	sl = zmalloc(sizeof(struct session_loglevel));
574a6217 MD	365	if (!sl)
1f18504e	366	return ERR_PTR(-ENOMEM);
574a6217 MD	367	sl->chan = chan;
	368	sl->enabled = 1;
	369	memcpy(&sl->event_param, event_param, sizeof(sl->event_param));
d5201d38	370	sl->event_param.instrumentation = LTTNG_UST_TRACEPOINT;
574a6217 MD	371	CDS_INIT_LIST_HEAD(&sl->events);
	372	cds_list_add(&sl->list, &chan->session->loglevels);
	373	cds_list_add(&sl->session_list, &e->session_list);
2981744d	374	sl->entry = e;
574a6217 MD	375	_probes_create_loglevel_events(e, sl);
574a6217 MD	376	return sl;
1f18504e MD	377	}
	378
	379	/*
	380	* Remove the loglevel from the loglevel hash table. Must be called with
	381	* ust_lock held. Only called at session teardown.
	382	*/
574a6217	383	void _remove_loglevel(struct session_loglevel *loglevel)
1f18504e MD	384	{
	385	struct ltt_event ev, tmp;
	386
	387	/*
	388	* Just remove the events owned (for enable/disable) by this
	389	* loglevel from the list. The session teardown will take care
	390	* of freeing the event memory.
	391	*/
66221151 MD	392	cds_list_for_each_entry_safe(ev, tmp, &loglevel->events,
	393	loglevel_list) {
	394	cds_list_del(&ev->loglevel_list);
1f18504e	395	}
574a6217	396	cds_list_del(&loglevel->session_list);
1f18504e	397	cds_list_del(&loglevel->list);
574a6217 MD	398	if (cds_list_empty(&loglevel->entry->session_list)) {
	399	cds_hlist_del(&loglevel->entry->hlist);
	400	free(loglevel->entry);
	401	}
1f18504e MD	402	free(loglevel);
	403	}
	404
574a6217	405	int ltt_loglevel_enable(struct session_loglevel *loglevel)
1f18504e MD	406	{
	407	struct ltt_event *ev;
	408	int ret;
	409
	410	if (loglevel->enabled)
	411	return -EEXIST;
66221151	412	cds_list_for_each_entry(ev, &loglevel->events, loglevel_list) {
1f18504e MD	413	ret = ltt_event_enable(ev);
	414	if (ret) {
	415	DBG("Error: enable error.\n");
	416	return ret;
	417	}
	418	}
	419	loglevel->enabled = 1;
	420	return 0;
	421	}
	422
574a6217	423	int ltt_loglevel_disable(struct session_loglevel *loglevel)
1f18504e MD	424	{
	425	struct ltt_event *ev;
	426	int ret;
	427
	428	if (!loglevel->enabled)
	429	return -EEXIST;
66221151	430	cds_list_for_each_entry(ev, &loglevel->events, loglevel_list) {
1f18504e MD	431	ret = ltt_event_disable(ev);
	432	if (ret) {
	433	DBG("Error: disable error.\n");
	434	return ret;
	435	}
	436	}
	437	loglevel->enabled = 0;
	438	return 0;
	439	}
e6c12e3d MD	440
	441	/* WILDCARDS */
	442
	443	/*
	444	* Return wildcard for a given event name if the event name match the
	445	* one of the wildcards.
	446	* Must be called with ust lock held.
	447	* Returns NULL if not present.
	448	*/
	449	struct wildcard_entry match_wildcard(const char name)
	450	{
	451	struct wildcard_entry *e;
	452
	453	cds_list_for_each_entry(e, &wildcard_list, list) {
	454	/* If only contain '' /
	455	if (strlen(e->name) == 1)
	456	return e;
	457	/* Compare excluding final '' /
	458	if (!strncmp(name, e->name, strlen(e->name) - 1))
	459	return e;
	460	}
	461	return NULL;
	462	}
	463
	464	/*
	465	* marshall all probes/all events and create those that fit the
	466	* wildcard. Add them to the events list as created.
	467	*/
	468	static
	469	void _probes_create_wildcard_events(struct wildcard_entry *entry,
	470	struct session_wildcard *wildcard)
	471	{
	472	struct lttng_probe_desc *probe_desc;
	473	struct lttng_ust_event event_param;
	474	int i;
	475
	476	cds_list_for_each_entry(probe_desc, &probe_list, head) {
	477	for (i = 0; i < probe_desc->nr_events; i++) {
	478	const struct lttng_event_desc *event_desc;
	479	int match = 0;
	480
	481	event_desc = probe_desc->event_desc[i];
	482	/* compare excluding final '' /
	483	assert(strlen(entry->name) > 0);
	484	if (strcmp(event_desc->name, "lttng_ust:metadata")
	485	&& (strlen(entry->name) == 1
	486	\|\| !strncmp(event_desc->name, entry->name,
	487	strlen(entry->name) - 1))) {
	488	match = 1;
	489	}
	490	if (match) {
	491	struct ltt_event *ev;
	492	int ret;
	493
	494	memcpy(&event_param, &wildcard->event_param,
	495	sizeof(event_param));
	496	memcpy(event_param.name,
	497	event_desc->name,
	498	sizeof(event_param.name));
	499	/* create event */
	500	ret = ltt_event_create(wildcard->chan,
	501	&event_param, NULL,
	502	&ev);
	503	if (ret) {
504	DBG("Error creating event");
505	continue;
506	}
507	cds_list_add(&ev->wildcard_list,
508	&wildcard->events);
509	}
510	}
511	}
512	}
513
514	/*
515	* Add the wildcard to the wildcard hash table. Must be called with
516	* ust lock held.
517	*/
518	struct session_wildcard add_wildcard(const char name,
519	struct ltt_channel *chan,
520	struct lttng_ust_event *event_param)
521	{
522	struct wildcard_entry *e;
523	struct session_wildcard *sw;
524	size_t name_len = strlen(name) + 1;
525	int found = 0;
526
527	/* wildcard entry */
528	cds_list_for_each_entry(e, &wildcard_list, list) {
ff412fb5	529	if (!strncmp(name, e->name, LTTNG_UST_SYM_NAME_LEN - 1)) {
e6c12e3d MD	530	found = 1;
	531	break;
	532	}
	533	}
	534
	535	if (!found) {
	536	/*
	537	* Using zmalloc here to allocate a variable length element. Could
	538	* cause some memory fragmentation if overused.
	539	*/
	540	e = zmalloc(sizeof(struct wildcard_entry) + name_len);
	541	if (!e)
	542	return ERR_PTR(-ENOMEM);
	543	memcpy(&e->name[0], name, name_len);
	544	cds_list_add(&e->list, &wildcard_list);
	545	CDS_INIT_LIST_HEAD(&e->session_list);
	546	}
	547
	548	/* session wildcard */
	549	cds_list_for_each_entry(sw, &e->session_list, session_list) {
	550	if (chan == sw->chan) {
	551	DBG("wildcard %s busy for this channel", name);
	552	return ERR_PTR(-EEXIST); /* Already there */
	553	}
	554	}
	555	sw = zmalloc(sizeof(struct session_wildcard));
	556	if (!sw)
	557	return ERR_PTR(-ENOMEM);
	558	sw->chan = chan;
	559	sw->enabled = 1;
	560	memcpy(&sw->event_param, event_param, sizeof(sw->event_param));
	561	sw->event_param.instrumentation = LTTNG_UST_TRACEPOINT;
	562	CDS_INIT_LIST_HEAD(&sw->events);
	563	cds_list_add(&sw->list, &chan->session->wildcards);
	564	cds_list_add(&sw->session_list, &e->session_list);
	565	sw->entry = e;
	566	_probes_create_wildcard_events(e, sw);
	567	return sw;
	568	}
	569
	570	/*
	571	* Remove the wildcard from the wildcard hash table. Must be called with
	572	* ust_lock held. Only called at session teardown.
	573	*/
	574	void _remove_wildcard(struct session_wildcard *wildcard)
	575	{
	576	struct ltt_event ev, tmp;
	577
	578	/*
	579	* Just remove the events owned (for enable/disable) by this
	580	* wildcard from the list. The session teardown will take care
	581	* of freeing the event memory.
	582	*/
66221151 MD	583	cds_list_for_each_entry_safe(ev, tmp, &wildcard->events,
	584	wildcard_list) {
	585	cds_list_del(&ev->wildcard_list);
e6c12e3d MD	586	}
	587	cds_list_del(&wildcard->session_list);
	588	cds_list_del(&wildcard->list);
	589	if (cds_list_empty(&wildcard->entry->session_list)) {
	590	cds_list_del(&wildcard->entry->list);
	591	free(wildcard->entry);
	592	}
	593	free(wildcard);
	594	}
	595
	596	int ltt_wildcard_enable(struct session_wildcard *wildcard)
	597	{
	598	struct ltt_event *ev;
	599	int ret;
	600
	601	if (wildcard->enabled)
	602	return -EEXIST;
66221151	603	cds_list_for_each_entry(ev, &wildcard->events, wildcard_list) {
e6c12e3d MD	604	ret = ltt_event_enable(ev);
	605	if (ret) {
	606	DBG("Error: enable error.\n");
	607	return ret;
	608	}
	609	}
	610	wildcard->enabled = 1;
	611	return 0;
	612	}
	613
	614	int ltt_wildcard_disable(struct session_wildcard *wildcard)
	615	{
	616	struct ltt_event *ev;
	617	int ret;
	618
	619	if (!wildcard->enabled)
	620	return -EEXIST;
66221151	621	cds_list_for_each_entry(ev, &wildcard->events, wildcard_list) {
e6c12e3d MD	622	ret = ltt_event_disable(ev);
	623	if (ret) {
	624	DBG("Error: disable error.\n");
	625	return ret;
	626	}
	627	}
	628	wildcard->enabled = 0;
	629	return 0;
	630	}