Support per UID buffers

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

diff --git a/src/bin/lttng-sessiond/trace-ust.h b/src/bin/lttng-sessiond/trace-ust.h
index f5fa092629d60e7030ac0b92aba0d943228268ab..87fe412d6b862ed0c5eed27af988c55affbdabbd 100644 (file)
--- a/src/bin/lttng-sessiond/trace-ust.h
+++ b/src/bin/lttng-sessiond/trace-ust.h
@@ -51,6 +51,7 @@ struct ltt_ust_event {
 
 /* UST channel */
 struct ltt_ust_channel {
+       uint64_t id;    /* unique id per session. */
        unsigned int enabled;
        char name[LTTNG_UST_SYM_NAME_LEN];
        char pathname[PATH_MAX];
@@ -72,20 +73,7 @@ struct ltt_ust_metadata {
 /* UST domain global (LTTNG_DOMAIN_UST) */
 struct ltt_ust_domain_global {
        struct lttng_ht *channels;
-};
-
-/* UST domain pid (LTTNG_DOMAIN_UST_PID) */
-struct ltt_ust_domain_pid {
-       pid_t pid;
-       struct lttng_ht *channels;
-       struct lttng_ht_node_ulong node;
-};
-
-/* UST domain exec name (LTTNG_DOMAIN_UST_EXEC_NAME) */
-struct ltt_ust_domain_exec {
-       char exec_name[LTTNG_UST_SYM_NAME_LEN];
-       struct lttng_ht *channels;
-       struct lttng_ht_node_str node;
+       struct cds_list_head registry_buffer_uid_list;
 };
 
 /* UST session */
@@ -94,13 +82,6 @@ struct ltt_ust_session {
        int start_trace;
        char pathname[PATH_MAX];
        struct ltt_ust_domain_global domain_global;
-       /*
-        * Those two hash tables contains data for a specific UST domain and each
-        * contains a HT of channels. See ltt_ust_domain_exec and
-        * ltt_ust_domain_pid data structures.
-        */
-       struct lttng_ht *domain_pid;
-       struct lttng_ht *domain_exec;
        /* UID/GID of the user owning the session */
        uid_t uid;
        gid_t gid;
@@ -114,8 +95,47 @@ struct ltt_ust_session {
        struct consumer_output *tmp_consumer;
        /* Sequence number for filters so the tracer knows the ordering. */
        uint64_t filter_seq_num;
+       /* This indicates which type of buffer this session is set for. */
+       enum lttng_buffer_type buffer_type;
+       /* If set to 1, the buffer_type can not be changed anymore. */
+       int buffer_type_changed;
+       /* For per UID buffer, every buffer reg object is kept of this session */
+       struct cds_list_head buffer_reg_uid_list;
+       /* Next channel ID available for a newly registered channel. */
+       uint64_t next_channel_id;
+       /* Once this value reaches UINT32_MAX, no more id can be allocated. */
+       uint64_t used_channel_id;
 };
 
+/*
+ * Validate that the id has reached the maximum allowed or not.
+ *
+ * Return 0 if NOT else 1.
+ */
+static inline int trace_ust_is_max_id(uint64_t id)
+{
+       return (id == UINT64_MAX) ? 1 : 0;
+}
+
+/*
+ * Return next available channel id and increment the used counter. The
+ * trace_ust_is_max_id function MUST be called before in order to validate if
+ * the maximum number of IDs have been reached. If not, it is safe to call this
+ * function.
+ *
+ * Return a unique channel ID. If max is reached, the used_channel_id counter
+ * is returned.
+ */
+static inline uint64_t trace_ust_get_next_chan_id(struct ltt_ust_session *s)
+{
+       if (trace_ust_is_max_id(s->used_channel_id)) {
+               return s->used_channel_id;
+       }
+
+       s->used_channel_id++;
+       return s->next_channel_id++;
+}
+
 #ifdef HAVE_LIBLTTNG_UST_CTL
 
 int trace_ust_ht_match_event(struct cds_lfht_node *node, const void *_key);