#include "jhash.h"
/*
- * The sessions mutex is the centralized mutex across UST tracing
- * control and probe registration. All operations within this file are
- * called by the communication thread, under ust_lock protection.
+ * All operations within this file are called by the communication
+ * thread, under ust_lock protection.
*/
-static pthread_mutex_t sessions_mutex = PTHREAD_MUTEX_INITIALIZER;
-
-void ust_lock(void)
-{
- pthread_mutex_lock(&sessions_mutex);
-}
-
-void ust_unlock(void)
-{
- pthread_mutex_unlock(&sessions_mutex);
-}
static CDS_LIST_HEAD(sessions);
enum lttng_ust_loglevel_type req_type,
int req_loglevel)
{
- if (req_type == LTTNG_UST_LOGLEVEL_ALL)
- return 1;
if (!has_loglevel)
loglevel = TRACE_DEFAULT;
switch (req_type) {
/* Set transient enabler state to "enabled" */
session->tstate = 1;
- /* We need to sync enablers with session before activation. */
- lttng_session_sync_enablers(session);
/*
* Snapshot the number of events per channel to know the type of header
}
}
+ /* We need to sync enablers with session before activation. */
+ lttng_session_sync_enablers(session);
+
/* Set atomically the state to "active" */
CMM_ACCESS_ONCE(session->active) = 1;
CMM_ACCESS_ONCE(session->been_active) = 1;
* Only dump state for the sessions owned by the caller thread, because
* we don't keep ust_lock across the entire iteration.
*/
-int lttng_handle_pending_statedump(void *owner)
+void lttng_handle_pending_statedump(void *owner)
{
struct lttng_session *session;
lttng_ust_baddr_statedump(owner);
/* Clear pending state dump */
- ust_lock();
+ if (ust_lock()) {
+ goto end;
+ }
cds_list_for_each_entry(session, &sessions, node) {
if (session->owner != owner)
continue;
continue;
session->statedump_pending = 0;
}
+end:
ust_unlock();
- return 0;
+ return;
}
/*
sizeof(enabler->event_param));
enabler->chan = chan;
/* ctx left NULL */
- enabler->enabled = 1;
+ /*
+ * The "disable" event create comm field has been added to fix a
+ * race between event creation (of a started trace) and enabling
+ * filtering. New session daemon always set the "disable" field
+ * to 1, and are aware that they need to explicitly enable the
+ * event. Older session daemon (within same ABI) leave it at 0,
+ * and therefore we need to enable it here, keeping the original
+ * racy behavior.
+ */
+ enabler->enabled = !event_param->disabled;
cds_list_add(&enabler->node, &enabler->chan->session->enablers_head);
lttng_session_lazy_sync_enablers(enabler->chan->session);
return enabler;