Fix: alignment of ring buffer shm space reservation

[lttng-ust.git] / libringbuffer / ring_buffer_backend.c

diff --git a/libringbuffer/ring_buffer_backend.c b/libringbuffer/ring_buffer_backend.c
index 431b8eae949250c1d51bbbe981aac84c42ee5edf..2dea1db51f537ca344206ec3daca965cd0745301 100644 (file)
--- a/libringbuffer/ring_buffer_backend.c
+++ b/libringbuffer/ring_buffer_backend.c
@@ -322,6 +322,13 @@ int channel_backend_init(struct channel_backend *chanb,
        /* Per-cpu buffer size: control (prior to backend) */
        shmsize = offset_align(shmsize, __alignof__(struct lttng_ust_lib_ring_buffer));
        shmsize += sizeof(struct lttng_ust_lib_ring_buffer);
+       shmsize += offset_align(shmsize, __alignof__(struct commit_counters_hot));
+       shmsize += sizeof(struct commit_counters_hot) * num_subbuf;
+       shmsize += offset_align(shmsize, __alignof__(struct commit_counters_cold));
+       shmsize += sizeof(struct commit_counters_cold) * num_subbuf;
+       /* Sampled timestamp end */
+       shmsize += offset_align(shmsize, __alignof__(uint64_t));
+       shmsize += sizeof(uint64_t) * num_subbuf;
 
        /* Per-cpu buffer size: backend */
        /* num_subbuf + 1 is the worse case */
@@ -336,14 +343,6 @@ int channel_backend_init(struct channel_backend *chanb,
        shmsize += sizeof(struct lttng_ust_lib_ring_buffer_backend_subbuffer) * num_subbuf;
        shmsize += offset_align(shmsize, __alignof__(struct lttng_ust_lib_ring_buffer_backend_counts));
        shmsize += sizeof(struct lttng_ust_lib_ring_buffer_backend_counts) * num_subbuf;
-       /* Per-cpu buffer size: control (after backend) */
-       shmsize += offset_align(shmsize, __alignof__(struct commit_counters_hot));
-       shmsize += sizeof(struct commit_counters_hot) * num_subbuf;
-       shmsize += offset_align(shmsize, __alignof__(struct commit_counters_cold));
-       shmsize += sizeof(struct commit_counters_cold) * num_subbuf;
-       /* Sampled timestamp end */
-       shmsize += offset_align(shmsize, __alignof__(uint64_t));
-       shmsize += sizeof(uint64_t) * num_subbuf;
 
        if (config->alloc == RING_BUFFER_ALLOC_PER_CPU) {
                struct lttng_ust_lib_ring_buffer *buf;