Add single disable UST event support

Support for disabling a single UST event for a specific channel.

Signed-off-by: David Goulet <david.goulet@polymtl.ca>

diff --git a/lttng-sessiond/main.c b/lttng-sessiond/main.c
index b2d421e56b15b8bd9e6534a35819d9755853d8f2..ae994d7e551956200265e5450e494627a376105c 100644 (file)
--- a/lttng-sessiond/main.c
+++ b/lttng-sessiond/main.c
@@ -2276,15 +2276,17 @@ static int cmd_disable_event(struct ltt_session *session, int domain,
        case LTTNG_DOMAIN_KERNEL:
        {
                struct ltt_kernel_channel *kchan;
+               struct ltt_kernel_session *ksess;
 
-               kchan = trace_kernel_get_channel_by_name(channel_name,
-                               session->kernel_session);
+               ksess = session->kernel_session;
+
+               kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
                if (kchan == NULL) {
                        ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
                        goto error;
                }
 
-               ret = event_kernel_disable_tracepoint(session->kernel_session, kchan, event_name);
+               ret = event_kernel_disable_tracepoint(ksess, kchan, event_name);
                if (ret != LTTCOMM_OK) {
                        goto error;
                }
@@ -2293,11 +2295,34 @@ static int cmd_disable_event(struct ltt_session *session, int domain,
                break;
        }
        case LTTNG_DOMAIN_UST:
+       {
+               struct ltt_ust_session *usess;
+               struct ltt_ust_channel *uchan;
+
+               usess = session->ust_session;
+
+               uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
+                               channel_name);
+               if (uchan == NULL) {
+                       ret = LTTCOMM_UST_CHAN_NOT_FOUND;
+                       goto error;
+               }
+
+               ret = ust_app_disable_event(usess, uchan, event_name);
+               if (ret < 0) {
+                       ret = LTTCOMM_UST_DISABLE_FAIL;
+                       goto error;
+               }
+
+               DBG2("Disable UST event %s in channel %s completed", event_name,
+                               channel_name);
+
+               break;
+       }
        case LTTNG_DOMAIN_UST_EXEC_NAME:
        case LTTNG_DOMAIN_UST_PID:
        case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
        default:
-               /* TODO: Other UST domains */
                ret = LTTCOMM_NOT_IMPLEMENTED;
                goto error;
        }

diff --git a/lttng-sessiond/ust-app.c b/lttng-sessiond/ust-app.c
index e0f907fbd0ff2d42b65f3a01fd4d33d9a33d03ee..d36cf8893535a24f8583638e25f342b2e33f05b7 100644 (file)
--- a/lttng-sessiond/ust-app.c
+++ b/lttng-sessiond/ust-app.c
@@ -1270,6 +1270,64 @@ error:
        return ret;
 }
 
+/*
+ * Disable an event in a channel and for a specific session.
+ */
+int ust_app_disable_event(struct ltt_ust_session *usess,
+               struct ltt_ust_channel *uchan, char *event_name)
+{
+       int ret = 0;
+       struct cds_lfht_iter iter, uiter;
+       struct cds_lfht_node *ua_chan_node, *ua_event_node;
+       struct ust_app *app;
+       struct ust_app_session *ua_sess;
+       struct ust_app_channel *ua_chan;
+       struct ust_app_event *ua_event;
+
+       DBG("UST app disabling event %s for all apps in channel "
+                       "%s for session uid %d", event_name, uchan->name, usess->uid);
+
+       rcu_read_lock();
+
+       /* For all registered applications */
+       cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
+               ua_sess = lookup_session_by_app(usess, app);
+               if (ua_sess == NULL) {
+                       /* Next app */
+                       continue;
+               }
+
+               /* Lookup channel in the ust app session */
+               ua_chan_node = hashtable_lookup(ua_sess->channels,
+                               (void *)uchan->name, strlen(uchan->name), &uiter);
+               if (ua_chan_node == NULL) {
+                       DBG2("Channel %s not found in session uid %d for app pid %d."
+                                       "Skipping", uchan->name, usess->uid, app->key.pid);
+                       continue;
+               }
+               ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
+
+               ua_event_node = hashtable_lookup(ua_chan->events,
+                               (void *) event_name, strlen(event_name), &uiter);
+               if (ua_event_node == NULL) {
+                       DBG2("Event %s not found in channel %s for app pid %d."
+                                       "Skipping", event_name, uchan->name, app->key.pid);
+                       continue;
+               }
+               ua_event = caa_container_of(ua_event_node, struct ust_app_event, node);
+
+               ret = disable_ust_app_event(ua_sess, ua_chan, ua_event, app);
+               if (ret < 0) {
+                       /* XXX: Report error someday... */
+                       continue;
+               }
+       }
+
+       rcu_read_unlock();
+
+       return ret;
+}
+
 /*
  * For a specific UST session and UST channel, create the event for all
  * registered apps.

diff --git a/lttng-sessiond/ust-app.h b/lttng-sessiond/ust-app.h
index dafca85b0203b86046826a301ab79fe4152b4284..17d6641bc70aa6b79f687a5825b8efcf7b58136c 100644 (file)
--- a/lttng-sessiond/ust-app.h
+++ b/lttng-sessiond/ust-app.h
@@ -128,6 +128,8 @@ int ust_app_enable_channel_all(struct ltt_ust_session *usess,
                struct ltt_ust_channel *uchan);
 int ust_app_disable_event_all(struct ltt_ust_session *usess,
                struct ltt_ust_channel *uchan);
+int ust_app_disable_event(struct ltt_ust_session *usess,
+               struct ltt_ust_channel *uchan, char *event_name);
 void ust_app_global_update(struct ltt_ust_session *usess, int sock);
 
 void ust_app_clean_list(void);