Fix memory layout for channel

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

diff --git a/libringbuffer/frontend_types.h b/libringbuffer/frontend_types.h
index 974f782e0dc86b3ed3903ec861ede6754504fbd9..baf1826321a2934f83b40992464dd2671615a2ef 100644 (file)
--- a/libringbuffer/frontend_types.h
+++ b/libringbuffer/frontend_types.h
@@ -44,12 +44,15 @@ struct channel {
                                                 * subbuffer index.
                                                 */
 
-       struct channel_backend backend;         /* Associated backend */
-
        unsigned long switch_timer_interval;    /* Buffer flush (jiffies) */
        unsigned long read_timer_interval;      /* Reader wakeup (jiffies) */
        //wait_queue_head_t read_wait;          /* reader wait queue */
        int finalized;                          /* Has channel been finalized */
+       /*
+        * Associated backend contains a variable-length array. Needs to
+        * be last member.
+        */
+       struct channel_backend backend;         /* Associated backend */
 } ____cacheline_aligned;
 
 /* Per-subbuffer commit counters used on the hot path */
@@ -87,6 +90,7 @@ struct lib_ring_buffer {
                                         * Active readers count
                                         * standard atomic access (shared)
                                         */
+       long active_shadow_readers;
                                        /* Dropped records */
        union v_atomic records_lost_full;       /* Buffer full */
        union v_atomic records_lost_wrap;       /* Nested wrap-around */
@@ -103,6 +107,8 @@ struct lib_ring_buffer {
        int get_subbuf:1;               /* Sub-buffer being held by reader */
        int switch_timer_enabled:1;     /* Protected by ring_buffer_nohz_lock */
        int read_timer_enabled:1;       /* Protected by ring_buffer_nohz_lock */
+       /* shmp pointer to self */
+       DECLARE_SHMP(struct lib_ring_buffer, self);
 } ____cacheline_aligned;
 
 static inline