Generate and export the sequence number

[lttng-ust.git] / libringbuffer / backend_types.h

diff --git a/libringbuffer/backend_types.h b/libringbuffer/backend_types.h
index a53fb322ec109bb2fc5c9cc275e5f0118dd67bf5..83fe04871dd26f0885b8859065b8d14cf277a552 100644 (file)
--- a/libringbuffer/backend_types.h
+++ b/libringbuffer/backend_types.h
@@ -42,6 +42,16 @@ struct lttng_ust_lib_ring_buffer_backend_subbuffer {
        unsigned long id;               /* backend subbuffer identifier */
 };
 
+struct lttng_ust_lib_ring_buffer_backend_counts {
+       /*
+        * Counter specific to the sub-buffer location within the ring buffer.
+        * The actual sequence number of the packet within the entire ring
+        * buffer can be derived from the formula nr_subbuffers * seq_cnt +
+        * subbuf_idx.
+        */
+       uint64_t seq_cnt;               /* packet sequence number */
+};
+
 /*
  * Forward declaration of frontend-specific channel and ring_buffer.
  */
@@ -58,6 +68,8 @@ struct lttng_ust_lib_ring_buffer_backend {
        DECLARE_SHMP(struct lttng_ust_lib_ring_buffer_backend_subbuffer, buf_wsb);
        /* ring_buffer_backend_subbuffer for reader */
        struct lttng_ust_lib_ring_buffer_backend_subbuffer buf_rsb;
+       /* Array of lib_ring_buffer_backend_counts for the packet counter */
+       DECLARE_SHMP(struct lttng_ust_lib_ring_buffer_backend_counts, buf_cnt);
        /*
         * Pointer array of backend pages, for whole buffer.
         * Indexed by ring_buffer_backend_subbuffer identifier (id) index.