Reactivate error printing

Print errors at buffer teardown if LTTNG_UST_DEBUG=1 is set (env. var.)
when launching the consumerd. This is possible now that consumerd owns
the buffers.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

diff --git a/libringbuffer/ring_buffer_frontend.c b/libringbuffer/ring_buffer_frontend.c
index 6719626c2d5672d1f4b32b1800e79f3fdd98f672..393aa9f0d30d50331a453d1435f3b0e2eacaf24c 100644 (file)
--- a/libringbuffer/ring_buffer_frontend.c
+++ b/libringbuffer/ring_buffer_frontend.c
@@ -105,15 +105,10 @@ struct switch_offsets {
 
 DEFINE_URCU_TLS(unsigned int, lib_ring_buffer_nesting);
 
-/*
- * TODO: this is unused. Errors are saved within the ring buffer.
- * Eventually, allow consumerd to print these errors.
- */
 static
 void lib_ring_buffer_print_errors(struct channel *chan,
-                                 struct lttng_ust_lib_ring_buffer *buf, int cpu,
-                                 struct lttng_ust_shm_handle *handle)
-       __attribute__((unused));
+                               struct lttng_ust_lib_ring_buffer *buf, int cpu,
+                               struct lttng_ust_shm_handle *handle);
 
 /**
  * lib_ring_buffer_reset - Reset ring buffer to initial values.
@@ -402,8 +397,31 @@ static void channel_unregister_notifiers(struct channel *chan,
        //channel_backend_unregister_notifiers(&chan->backend);
 }
 
-static void channel_free(struct channel *chan, struct lttng_ust_shm_handle *handle)
+static void channel_print_errors(struct channel *chan,
+               struct lttng_ust_shm_handle *handle)
+{
+       const struct lttng_ust_lib_ring_buffer_config *config =
+                       &chan->backend.config;
+       int cpu;
+
+       if (config->alloc == RING_BUFFER_ALLOC_PER_CPU) {
+               for_each_possible_cpu(cpu) {
+                       struct lttng_ust_lib_ring_buffer *buf =
+                               shmp(handle, chan->backend.buf[cpu].shmp);
+                       lib_ring_buffer_print_errors(chan, buf, cpu, handle);
+               }
+       } else {
+               struct lttng_ust_lib_ring_buffer *buf =
+                       shmp(handle, chan->backend.buf[0].shmp);
+
+               lib_ring_buffer_print_errors(chan, buf, -1, handle);
+       }
+}
+
+static void channel_free(struct channel *chan,
+               struct lttng_ust_shm_handle *handle)
 {
+       channel_print_errors(chan, handle);
        channel_backend_free(&chan->backend, handle);
        /* chan is freed by shm teardown */
        shm_object_table_destroy(handle->table);
@@ -1014,8 +1032,8 @@ void lib_ring_buffer_print_buffer_errors(struct lttng_ust_lib_ring_buffer *buf,
 
 static
 void lib_ring_buffer_print_errors(struct channel *chan,
-                                 struct lttng_ust_lib_ring_buffer *buf, int cpu,
-                                 struct lttng_ust_shm_handle *handle)
+                               struct lttng_ust_lib_ring_buffer *buf, int cpu,
+                               struct lttng_ust_shm_handle *handle)
 {
        const struct lttng_ust_lib_ring_buffer_config *config = &chan->backend.config;
        void *priv = channel_get_private(chan);