Add loglevel enable/disable support

[lttng-ust.git] / include / lttng / ust-events.h

diff --git a/include/lttng/ust-events.h b/include/lttng/ust-events.h
index 0a03193920229cc6406f51b0752b4744309f587c..5867b124878c6993291591094d049634c5c699f1 100644 (file)
--- a/include/lttng/ust-events.h
+++ b/include/lttng/ust-events.h
@@ -19,6 +19,7 @@
  */
 
 #include <urcu/list.h>
+#include <urcu/hlist.h>
 #include <uuid/uuid.h>
 #include <stdint.h>
 #include <lttng/ust-abi.h>
@@ -188,6 +189,22 @@ struct tracepoint_loglevel_entry  {
        long value;
 };
 
+/*
+ * Entry describing an active loglevel, along with the event attribute
+ * and channel information configuring the events that need to be
+ * enabled.
+ */
+struct loglevel_entry {
+       struct cds_hlist_node hlist;
+       struct ltt_channel *chan;
+       struct lttng_ctx *ctx;  /* TODO */
+       struct lttng_ust_event event_param;
+       struct cds_list_head events;    /* list of events enabled */
+       struct cds_list_head list;      /* per-session list of loglevels */
+       unsigned int enabled:1;
+       char name[0];
+};
+
 struct lttng_event_desc {
        const char *name;
        void *probe_callback;
@@ -221,6 +238,9 @@ struct ust_pending_probe;
 /*
  * ltt_event structure is referred to by the tracing fast path. It must be
  * kept small.
+ * Note about loglevel_list: this list is only used to enable/disable
+ * events on a per-loglevel basis. The events created internally by the
+ * loglevel are only freed when the session is destroyed.
  */
 struct ltt_event {
        unsigned int id;
@@ -233,6 +253,7 @@ struct ltt_event {
        union {
        } u;
        struct cds_list_head list;              /* Event list */
+       struct cds_list_head loglevel_list;     /* Event list for loglevel */
        struct ust_pending_probe *pending_probe;
        unsigned int metadata_dumped:1;
 };
@@ -309,6 +330,7 @@ struct ltt_session {
        struct ltt_channel *metadata;   /* Metadata channel */
        struct cds_list_head chan;      /* Channel list head */
        struct cds_list_head events;    /* Event list head */
+       struct cds_list_head loglevels; /* Loglevel list head */
        struct cds_list_head list;      /* Session list */
        unsigned int free_chan_id;      /* Next chan ID to allocate */
        uuid_t uuid;                    /* Trace session unique ID */
@@ -388,4 +410,15 @@ void ltt_probes_prune_event_list(struct lttng_ust_tracepoint_list *list);
 struct lttng_ust_tracepoint_iter *
        lttng_ust_tracepoint_list_get_iter_next(struct lttng_ust_tracepoint_list *list);
 
+struct loglevel_entry *get_loglevel(const char *name);
+struct loglevel_entry *add_loglevel(const char *name,
+       struct ltt_channel *chan,
+       struct lttng_ust_event *event_param);
+void _remove_loglevel(struct loglevel_entry *e);
+int ltt_loglevel_enable(struct loglevel_entry *loglevel);
+int ltt_loglevel_disable(struct loglevel_entry *loglevel);
+int ltt_loglevel_create(struct ltt_channel *chan,
+       struct lttng_ust_event *event_param,
+       struct loglevel_entry **_entry);
+
 #endif /* _LTTNG_UST_EVENTS_H */