Change the UST event hash table match function

[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 4c7dac8b72111f33904e7fef69a53e77578171cb..962255b5c930989100600592253e56589b1fe22d 100644 (file)
--- a/src/bin/lttng-sessiond/trace-ust.c
+++ b/src/bin/lttng-sessiond/trace-ust.c
@@ -26,6 +26,96 @@
 
 #include "trace-ust.h"
 
+int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
+               const void *_key)
+{
+       struct ltt_ust_event *event;
+       const char *name;
+
+       assert(node);
+       assert(_key);
+
+       event = caa_container_of(node, struct ltt_ust_event, node.node);
+       name = _key;
+
+       /* Event name */
+       if (strncmp(event->attr.name, name, sizeof(event->attr.name)) != 0) {
+               goto no_match;
+       }
+
+       /* Match. */
+       return 1;
+
+no_match:
+       return 0;
+}
+
+int trace_ust_ht_match_event(struct cds_lfht_node *node, const void *_key)
+{
+       struct ltt_ust_event *event;
+       const struct ltt_ust_ht_key *key;
+
+       assert(node);
+       assert(_key);
+
+       event = caa_container_of(node, struct ltt_ust_event, node.node);
+       key = _key;
+
+       /* Match the 3 elements of the key: name, filter and loglevel. */
+
+       /* Event name */
+       if (strncmp(event->attr.name, key->name, sizeof(event->attr.name)) != 0) {
+               DBG3("[Match] name failed: %s and %s",
+                               event->attr.name, key->name);
+               goto no_match;
+       }
+
+       /* Event loglevel. */
+       if (event->attr.loglevel != key->loglevel) {
+               if (event->attr.loglevel_type == 0 && key->loglevel == 0 &&
+                               event->attr.loglevel == -1) {
+                       /*
+                        * This is because on event creation, the loglevel is set to -1 if
+                        * the event loglevel type is ALL so 0 and -1 are accepted for this
+                        * loglevel type.
+                        */
+               } else {
+                       DBG3("[Match] loglevel failed: %d and %d",
+                                       event->attr.loglevel, key->loglevel);
+                       goto no_match;
+               }
+       }
+
+       /* Only one of the filters is NULL, fail. */
+       if ((key->filter && !event->filter) || (!key->filter && event->filter)) {
+               DBG3("[Match] filters failed: k:%p and e:%p",
+                               key->filter, event->filter);
+               goto no_match;
+       }
+
+       /* Both filters are NULL, success. */
+       if (!key->filter && !event->filter) {
+               goto match;
+       }
+
+       /* Both filters exists, check length followed by the bytecode. */
+       if (event->filter->len == key->filter->len &&
+                       memcmp(event->filter->data, key->filter->data,
+                               event->filter->len) == 0) {
+               goto match;
+       }
+
+       DBG3("[Match] filters failed: k:%p and e:%p",
+                       key->filter, event->filter);
+
+no_match:
+       return 0;
+
+match:
+       DBG3("[MATCH] %s", key->name);
+       return 1;
+}
+
 /*
  * Find the channel in the hashtable.
  */
@@ -56,27 +146,40 @@ error:
 /*
  * Find the event in the hashtable.
  */
-struct ltt_ust_event *trace_ust_find_event_by_name(struct lttng_ht *ht,
-               char *name)
+struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
+               char *name, struct lttng_filter_bytecode *filter, int loglevel)
 {
        struct lttng_ht_node_str *node;
        struct lttng_ht_iter iter;
+       struct ltt_ust_ht_key key;
+       void *orig_match_fct;
 
-       rcu_read_lock();
-       lttng_ht_lookup(ht, (void *) name, &iter);
+       assert(name);
+       assert(ht);
+
+       key.name = name;
+       key.filter = filter;
+       key.loglevel = loglevel;
+
+       /* Save match function so we can use the ust app event match. */
+       orig_match_fct = (void *) ht->match_fct;
+       ht->match_fct = trace_ust_ht_match_event;
+
+       cds_lfht_lookup(ht->ht, ht->hash_fct((void *) name, lttng_ht_seed),
+                       trace_ust_ht_match_event, &key, &iter.iter);
        node = lttng_ht_iter_get_node_str(&iter);
        if (node == NULL) {
-               rcu_read_unlock();
                goto error;
        }
-       rcu_read_unlock();
 
-       DBG2("Trace UST event found by name %s", name);
+       DBG2("Trace UST event %s found", key.name);
 
        return caa_container_of(node, struct ltt_ust_event, node);
 
 error:
-       DBG2("Trace UST event NOT found by name %s", name);
+       DBG2("Trace UST event %s NOT found", key.name);
+       /* Put back original match function. */
+       ht->match_fct = orig_match_fct;
        return NULL;
 }