X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=liblttng-ust%2Fltt-probes.c;h=9667497aac6e5f66f8309237365c6ac1851f5578;hb=e6c12e3dd164fcab19db5985f8729e3d1767571c;hp=b683b81bb24107a769cbdfe3eaeedb0be1ac85c7;hpb=3431ca3eea9bfaab6ced44922beb9e6bb7a2abc1;p=lttng-ust.git

diff --git a/liblttng-ust/ltt-probes.c b/liblttng-ust/ltt-probes.c
index b683b81b..9667497a 100644
--- a/liblttng-ust/ltt-probes.c
+++ b/liblttng-ust/ltt-probes.c
@@ -34,6 +34,12 @@ static CDS_LIST_HEAD(probe_list);
 #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)
 {
@@ -416,3 +422,193 @@ int ltt_loglevel_disable(struct session_loglevel *loglevel)
 	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 (!strcmp(name, e->name)) {
+			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, list) {
+		cds_list_del(&ev->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, 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, list) {
+		ret = ltt_event_disable(ev);
+		if (ret) {
+			DBG("Error: disable error.\n");
+			return ret;
+		}
+	}
+	wildcard->enabled = 0;
+	return 0;
+}