static DEFINE_MUTEX(sessions_mutex);
static struct kmem_cache *event_cache;
-struct ltt_session *ltt_session_create(char *name)
+static void synchronize_trace(void)
+{
+ synchronize_sched();
+#ifdef CONFIG_PREEMPT_RT
+ synchronize_rcu();
+#endif
+}
+
+struct ltt_session *ltt_session_create(void)
{
struct ltt_session *session;
mutex_lock(&sessions_mutex);
- list_for_each_entry(session, &sessions, list)
- if (!strcmp(session->name, name))
- goto exist;
- session = kmalloc(sizeof(struct ltt_session) + strlen(name) + 1);
+ session = kmalloc(sizeof(struct ltt_session));
if (!session)
return NULL;
- strcpy(session->name, name);
INIT_LIST_HEAD(&session->chan);
list_add(&session->list, &sessions);
mutex_unlock(&sessions_mutex);
struct ltt_event *event, *tmpevent;
mutex_lock(&sessions_mutex);
+ session->active = 0;
+ synchronize_trace(); /* Wait for in-flight events to complete */
list_for_each_entry_safe(event, tmpevent, &session->events, list)
_ltt_event_destroy(event);
list_for_each_entry_safe(chan, tmpchan, &session->chan, list)
kfree(session);
}
-struct ltt_channel *ltt_channel_create(struct ltt_session *session, char *name,
+struct ltt_channel *ltt_channel_create(struct ltt_session *session,
int overwrite, void *buf_addr,
size_t subbuf_size, size_t num_subbuf,
unsigned int switch_timer_interval,
mutex_lock(&sessions_mutex);
if (session->active)
goto active; /* Refuse to add channel to active session */
- list_for_each_entry(chan, &session->chan, list)
- if (!strcmp(chan->name, name))
- goto exist;
- chan = kmalloc(sizeof(struct ltt_channel) + strlen(name) + 1, GFP_KERNEL);
+ chan = kmalloc(sizeof(struct ltt_channel), GFP_KERNEL);
if (!chan)
return NULL;
- strcpy(chan->name, name);
chan->session = session;
+ init_waitqueue_head(&chan->notify_wait);
/* TODO: create rb channel */
list_add(&chan->list, &session->chan);
*/
int _ltt_channel_destroy(struct ltt_channel *chan)
{
+ /* TODO: destroy rb channel */
list_del(&chan->list);
kfree(chan);
}
* Supports event creation while tracing session is active.
*/
struct ltt_event *ltt_event_create(struct ltt_channel *chan, char *name,
- void *filter)
+ enum instrum_type itype,
+ void *probe, void *filter)
{
struct ltt_event *event;
+ int ret;
mutex_lock(&sessions_mutex);
if (chan->free_event_id == -1UL)
goto error;
strcpy(event->name, name);
event->chan = chan;
+ event->probe = probe;
event->filter = filter;
event->id = chan->free_event_id++;
+ event->itype = itype;
mutex_unlock(&sessions_mutex);
/* Populate ltt_event structure before tracepoint registration. */
smp_wmb();
- /* TODO register to tracepoint */
+ switch (itype) {
+ case INSTRUM_TRACEPOINTS:
+ ret = tracepoint_probe_register(name, probe, event);
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ }
return event;
error:
*/
int _ltt_event_destroy(struct ltt_event *event)
{
- /* TODO unregister from tracepoint */
+ switch (event->itype) {
+ case INSTRUM_TRACEPOINTS:
+ ret = tracepoint_probe_unregister(name, event->probe, event);
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ }
kfree(event->name);
kmem_cache_free(event);
}
events_cache = KMEM_CACHE(ltt_event, 0);
if (!events_cache)
return -ENOMEM;
+
+ /* TODO: show ABI to userspace */
+
return 0;
}
static void __exit ltt_events_exit(void)
{
+ struct ltt_session *session, *tmpsession;
+
+ /* TODO: hide ABI from userspace, wait for callers to release refs. */
+
+ list_for_each_entry_safe(session, tmpsession, &sessions, list)
+ ltt_session_destroy(session);
kmem_cache_destroy(events_cache);
}
+
+MODULE_LICENSE("GPL and additional rights");
+MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
+MODULE_DESCRIPTION("LTTng Events");