Fix: wait for the completion of implicit session rotations

[lttng-tools.git] / src / bin / lttng-sessiond / session.c

diff --git a/src/bin/lttng-sessiond/session.c b/src/bin/lttng-sessiond/session.c
index abac2404f04bdda9b2c3a94ec8507c950f3a427a..4a15c9a9ad53eac1106c01f380bea8f70c114985 100644 (file)
--- a/src/bin/lttng-sessiond/session.c
+++ b/src/bin/lttng-sessiond/session.c
@@ -40,6 +40,11 @@
 #include "trace-ust.h"
 #include "timer.h"
 
 #include "trace-ust.h"
 #include "timer.h"
 

+struct ltt_session_destroy_notifier_element {
+       ltt_session_destroy_notifier notifier;
+       void *user_data;
+};
+

 /*
  * NOTES:
  *
 /*
  * NOTES:
  *


@@ -245,7 +250,7 @@ void session_get_net_consumer_ports(const struct ltt_session *session,
  * The caller must hold the session lock.
  */
 struct lttng_trace_archive_location *session_get_trace_archive_location(
  * The caller must hold the session lock.
  */
 struct lttng_trace_archive_location *session_get_trace_archive_location(

-               struct ltt_session *session)
+               const struct ltt_session *session)

 {
        int ret;
        struct lttng_trace_archive_location *location = NULL;
 {
        int ret;
        struct lttng_trace_archive_location *location = NULL;


@@ -737,6 +742,22 @@ int session_set_trace_chunk(struct ltt_session *session,
                        current_trace_chunk);
 }
 
                        current_trace_chunk);
 }
 

+static
+void session_notify_destruction(const struct ltt_session *session)
+{
+       size_t i;
+       const size_t count = lttng_dynamic_array_get_count(
+                       &session->destroy_notifiers);
+
+       for (i = 0; i < count; i++) {
+               const struct ltt_session_destroy_notifier_element *element =
+                       lttng_dynamic_array_get_element(
+                                       &session->destroy_notifiers, i);
+
+               element->notifier(session, element->user_data);
+       }
+}
+

 static
 void session_release(struct urcu_ref *ref)
 {
 static
 void session_release(struct urcu_ref *ref)
 {


@@ -749,6 +770,9 @@ void session_release(struct urcu_ref *ref)
 
        usess = session->ust_session;
        ksess = session->kernel_session;
 
        usess = session->ust_session;
        ksess = session->kernel_session;

+
+       session_notify_destruction(session);
+       lttng_dynamic_array_reset(&session->destroy_notifiers, NULL);

        if (session->current_trace_chunk) {
                ret = session_close_trace_chunk(session, session->current_trace_chunk);
                if (ret) {
        if (session->current_trace_chunk) {
                ret = session_close_trace_chunk(session, session->current_trace_chunk);
                if (ret) {


@@ -852,6 +876,18 @@ void session_destroy(struct ltt_session *session)
        session_put(session);
 }
 
        session_put(session);
 }
 

+int session_add_destroy_notifier(struct ltt_session *session,
+               ltt_session_destroy_notifier notifier, void *user_data)
+{
+       const struct ltt_session_destroy_notifier_element element = {
+               .notifier = notifier,
+               .user_data = user_data
+       };
+
+       return lttng_dynamic_array_add_element(&session->destroy_notifiers,
+                       &element);
+}
+

 /*
  * Return a ltt_session structure ptr that matches name. If no session found,
  * NULL is returned. This must be called with the session list lock held using
 /*
  * Return a ltt_session structure ptr that matches name. If no session found,
  * NULL is returned. This must be called with the session list lock held using


@@ -940,6 +976,8 @@ enum lttng_error_code session_create(const char *name, uid_t uid, gid_t gid,
                goto error;
        }
 
                goto error;
        }
 

+       lttng_dynamic_array_init(&new_session->destroy_notifiers,
+                       sizeof(struct ltt_session_destroy_notifier_element));

        urcu_ref_init(&new_session->ref);
        pthread_mutex_init(&new_session->lock, NULL);
 
        urcu_ref_init(&new_session->ref);
        pthread_mutex_init(&new_session->lock, NULL);