X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=libringbuffer%2Fring_buffer_backend.c;h=b65105f3a92afdfc8eceab615b73708bb045307e;hb=382cbd153bc0240b75d1bece7564c900599534b4;hp=0d2cc6d0359af249e4c65e4cd4f0b9d0efbe2f0f;hpb=22b22ce98477138d3e694cd66a3040d450946963;p=lttng-ust.git

diff --git a/libringbuffer/ring_buffer_backend.c b/libringbuffer/ring_buffer_backend.c
index 0d2cc6d0..b65105f3 100644
--- a/libringbuffer/ring_buffer_backend.c
+++ b/libringbuffer/ring_buffer_backend.c
@@ -115,7 +115,6 @@ int lib_ring_buffer_backend_allocate(const struct lttng_ust_lib_ring_buffer_conf
 			mmap_offset += subbuf_size;
 		}
 	}
-
 	return 0;
 
 free_array:
@@ -199,6 +198,7 @@ void channel_backend_reset(struct channel_backend *chanb)
  * @subbuf_size: size of sub-buffers (> PAGE_SIZE, power of 2)
  * @num_subbuf: number of sub-buffers (power of 2)
  * @lttng_ust_shm_handle: shared memory handle
+ * @stream_fds: stream file descriptors.
  *
  * Returns channel pointer if successful, %NULL otherwise.
  *
@@ -212,7 +212,8 @@ int channel_backend_init(struct channel_backend *chanb,
 			 const char *name,
 			 const struct lttng_ust_lib_ring_buffer_config *config,
 			 size_t subbuf_size, size_t num_subbuf,
-			 struct lttng_ust_shm_handle *handle)
+			 struct lttng_ust_shm_handle *handle,
+			 const int *stream_fds)
 {
 	struct channel *chan = caa_container_of(chanb, struct channel, backend);
 	unsigned int i;
@@ -234,6 +235,12 @@ int channel_backend_init(struct channel_backend *chanb,
 		return -EINVAL;
 	if (!num_subbuf || (num_subbuf & (num_subbuf - 1)))
 		return -EINVAL;
+	/*
+	 * Overwrite mode buffers require at least 2 subbuffers per
+	 * buffer.
+	 */
+	if (config->mode == RING_BUFFER_OVERWRITE && num_subbuf < 2)
+		return -EINVAL;
 
 	ret = subbuffer_id_check_index(config, num_subbuf);
 	if (ret)
@@ -281,7 +288,7 @@ int channel_backend_init(struct channel_backend *chanb,
 			struct shm_object *shmobj;
 
 			shmobj = shm_object_table_alloc(handle->table, shmsize,
-					SHM_OBJECT_SHM);
+					SHM_OBJECT_SHM, stream_fds[i]);
 			if (!shmobj)
 				goto end;
 			align_shm(shmobj, __alignof__(struct lttng_ust_lib_ring_buffer));
@@ -300,7 +307,7 @@ int channel_backend_init(struct channel_backend *chanb,
 		struct lttng_ust_lib_ring_buffer *buf;
 
 		shmobj = shm_object_table_alloc(handle->table, shmsize,
-					SHM_OBJECT_SHM);
+					SHM_OBJECT_SHM, stream_fds[0]);
 		if (!shmobj)
 			goto end;
 		align_shm(shmobj, __alignof__(struct lttng_ust_lib_ring_buffer));