Fix: define _LGPL_SOURCE in C files

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

diff --git a/src/bin/lttng-sessiond/trace-ust.c b/src/bin/lttng-sessiond/trace-ust.c
index 9c22e38901144a00041d6176d5d5ef887777e5e2..0e386aa0327f2f430806321766e2a4e2516b64dc 100644 (file)
--- a/src/bin/lttng-sessiond/trace-ust.c
+++ b/src/bin/lttng-sessiond/trace-ust.c
@@ -16,6 +16,7 @@
  */
 
 #define _GNU_SOURCE
+#define _LGPL_SOURCE
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -199,6 +200,38 @@ error:
        return NULL;
 }
 
+/*
+ * Lookup an agent in the session agents hash table by domain type and return
+ * the object if found else NULL.
+ *
+ * RCU read side lock must be acquired before calling and only released
+ * once the agent is no longer in scope or being used.
+ */
+struct agent *trace_ust_find_agent(struct ltt_ust_session *session,
+               enum lttng_domain_type domain_type)
+{
+       struct agent *agt = NULL;
+       struct lttng_ht_node_u64 *node;
+       struct lttng_ht_iter iter;
+       uint64_t key;
+
+       assert(session);
+
+       DBG3("Trace ust agent lookup for domain %d", domain_type);
+
+       key = domain_type;
+
+       lttng_ht_lookup(session->agents, &key, &iter);
+       node = lttng_ht_iter_get_node_u64(&iter);
+       if (!node) {
+               goto end;
+       }
+       agt = caa_container_of(node, struct agent, node);
+
+end:
+       return agt;
+}
+
 /*
  * Allocate and initialize a ust session data structure.
  *
@@ -206,7 +239,6 @@ error:
  */
 struct ltt_ust_session *trace_ust_create_session(uint64_t session_id)
 {
-       int ret;
        struct ltt_ust_session *lus;
 
        /* Allocate a new ltt ust session */
@@ -242,10 +274,8 @@ struct ltt_ust_session *trace_ust_create_session(uint64_t session_id)
 
        /* Alloc UST global domain channels' HT */
        lus->domain_global.channels = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
-       ret = agent_init(&lus->agent);
-       if (ret < 0) {
-               goto error_consumer;
-       }
+       /* Alloc agent hash table. */
+       lus->agents = lttng_ht_new(0, LTTNG_HT_TYPE_U64);
 
        lus->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
        if (lus->consumer == NULL) {
@@ -266,7 +296,7 @@ struct ltt_ust_session *trace_ust_create_session(uint64_t session_id)
 
 error_consumer:
        ht_cleanup_push(lus->domain_global.channels);
-       agent_destroy(&lus->agent);
+       ht_cleanup_push(lus->agents);
        free(lus);
 error:
        return NULL;
@@ -712,7 +742,9 @@ static void destroy_domain_global(struct ltt_ust_domain_global *dom)
  */
 void trace_ust_destroy_session(struct ltt_ust_session *session)
 {
+       struct agent *agt;
        struct buffer_reg_uid *reg, *sreg;
+       struct lttng_ht_iter iter;
 
        assert(session);
 
@@ -720,7 +752,13 @@ void trace_ust_destroy_session(struct ltt_ust_session *session)
 
        /* Cleaning up UST domain */
        destroy_domain_global(&session->domain_global);
-       agent_destroy(&session->agent);
+
+       rcu_read_lock();
+       cds_lfht_for_each_entry(session->agents->ht, &iter.iter, agt, node.node) {
+               lttng_ht_del(session->agents, &iter);
+               agent_destroy(agt);
+       }
+       rcu_read_unlock();
 
        /* Cleanup UID buffer registry object(s). */
        cds_list_for_each_entry_safe(reg, sreg, &session->buffer_reg_uid_list,