Implement filter bytecode support in lttng-session, and parse filter string

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

diff --git a/src/bin/lttng-sessiond/ust-app.c b/src/bin/lttng-sessiond/ust-app.c
index c8c653134f7528e2cea26f0d333fc655881fe9e0..6fb328eb9ca0cfd991328d227445d1aa6fbdadca 100644 (file)
--- a/src/bin/lttng-sessiond/ust-app.c
+++ b/src/bin/lttng-sessiond/ust-app.c
@@ -32,6 +32,7 @@
 #include "ust-consumer.h"
 #include "ust-ctl.h"
 #include "fd-limit.h"
+#include "../../common/sessiond-comm/sessiond-comm.h"
 
 /*
  * Delete ust context safely. RCU read lock must be held before calling
@@ -65,6 +66,7 @@ void delete_ust_app_event(int sock, struct ust_app_event *ua_event)
                assert(!ret);
                delete_ust_app_ctx(sock, ua_ctx);
        }
+       free(ua_event->filter);
        lttng_ht_destroy(ua_event->ctx);
 
        if (ua_event->obj != NULL) {
@@ -430,6 +432,31 @@ error:
        return ret;
 }
 
+/*
+ * Set the filter on the tracer.
+ */
+static
+int set_ust_event_filter(struct ust_app_event *ua_event,
+               struct ust_app *app)
+{
+       int ret;
+
+       if (!ua_event->filter) {
+               return 0;
+       }
+
+       ret = ustctl_set_filter(app->sock, ua_event->filter,
+                       ua_event->obj);
+       if (ret < 0) {
+               goto error;
+       }
+
+       DBG2("UST filter set successfully for event %s", ua_event->name);
+
+error:
+       return ret;
+}
+
 /*
  * Disable the specified event on to UST tracer for the UST session.
  */
@@ -705,6 +732,16 @@ static void shadow_copy_event(struct ust_app_event *ua_event,
        /* Copy event attributes */
        memcpy(&ua_event->attr, &uevent->attr, sizeof(ua_event->attr));
 
+       /* Copy filter bytecode */
+       if (uevent->filter) {
+               ua_event->filter = zmalloc(sizeof(*ua_event->filter) +
+                       uevent->filter->len);
+               if (!ua_event->filter) {
+                       return;
+               }
+               memcpy(ua_event->filter, uevent->filter,
+                       sizeof(*ua_event->filter) + uevent->filter->len);
+       }
        cds_lfht_for_each_entry(uevent->ctx->ht, &iter.iter, uctx, node.node) {
                ua_ctx = alloc_ust_app_ctx(&uctx->ctx);
                if (ua_ctx == NULL) {
@@ -997,6 +1034,35 @@ error:
        return ret;
 }
 
+/*
+ * Set UST filter for the event on the tracer.
+ */
+static
+int set_ust_app_event_filter(struct ust_app_session *ua_sess,
+               struct ust_app_event *ua_event,
+               struct lttng_filter_bytecode *bytecode,
+               struct ust_app *app)
+{
+       int ret = 0;
+
+       DBG2("UST app adding context to event %s", ua_event->name);
+
+       /* Copy filter bytecode */
+       ua_event->filter = zmalloc(sizeof(*ua_event->filter) + bytecode->len);
+       if (!ua_event->filter) {
+               return -ENOMEM;
+       }
+       memcpy(ua_event->filter, bytecode,
+               sizeof(*ua_event->filter) + bytecode->len);
+       ret = set_ust_event_filter(ua_event, app);
+       if (ret < 0) {
+               goto error;
+       }
+
+error:
+       return ret;
+}
+
 /*
  * Enable on the tracer side a ust app event for the session and channel.
  */
@@ -2419,6 +2485,11 @@ void ust_app_global_update(struct ltt_ust_session *usess, int sock)
                                        continue;
                                }
                        }
+                       ret = set_ust_event_filter(ua_event, app);
+                       if (ret < 0) {
+                               /* FIXME: Should we quit here or continue... */
+                               continue;
+                       }
                }
        }
 
@@ -2540,6 +2611,63 @@ int ust_app_add_ctx_event_glb(struct ltt_ust_session *usess,
        return ret;
 }
 
+/*
+ * Add context to a specific event in a channel for global UST domain.
+ */
+int ust_app_set_filter_event_glb(struct ltt_ust_session *usess,
+               struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent,
+               struct lttng_filter_bytecode *bytecode)
+{
+       int ret = 0;
+       struct lttng_ht_node_str *ua_chan_node, *ua_event_node;
+       struct lttng_ht_iter iter, uiter;
+       struct ust_app_session *ua_sess;
+       struct ust_app_event *ua_event;
+       struct ust_app_channel *ua_chan = NULL;
+       struct ust_app *app;
+
+       rcu_read_lock();
+
+       cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
+               if (!app->compatible) {
+                       /*
+                        * TODO: In time, we should notice the caller of this error by
+                        * telling him that this is a version error.
+                        */
+                       continue;
+               }
+               ua_sess = lookup_session_by_app(usess, app);
+               if (ua_sess == NULL) {
+                       continue;
+               }
+
+               /* Lookup channel in the ust app session */
+               lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
+               ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
+               if (ua_chan_node == NULL) {
+                       continue;
+               }
+               ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel,
+                               node);
+
+               lttng_ht_lookup(ua_chan->events, (void *)uevent->attr.name, &uiter);
+               ua_event_node = lttng_ht_iter_get_node_str(&uiter);
+               if (ua_event_node == NULL) {
+                       continue;
+               }
+               ua_event = caa_container_of(ua_event_node, struct ust_app_event,
+                               node);
+
+               ret = set_ust_app_event_filter(ua_sess, ua_event, bytecode, app);
+               if (ret < 0) {
+                       continue;
+               }
+       }
+
+       rcu_read_unlock();
+       return ret;
+}
+
 /*
  * Enable event for a channel from a UST session for a specific PID.
  */