[lttng-dev] [PATCH lttng-tools 1/2] Fix: handle backward compatibility with lttng-modules 2.7

[Jérémie Galarneau]

Merged in master and stable-2.8. Thanks!

Jérémie

On 5 October 2016 at 12:54, Mathieu Desnoyers
<mathieu.desnoyers at efficios.com> wrote:
> There is no major version bump between lttng-module 2.7 and 2.8 ABI.
> Even though we do not guarantee compatibility, do a best effort to
> maintain it when possible.
>
> Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
> ---
>  src/common/kernel-consumer/kernel-consumer.c | 38 +++++++++++++++++++++++-----
>  1 file changed, 32 insertions(+), 6 deletions(-)
>
> diff --git a/src/common/kernel-consumer/kernel-consumer.c b/src/common/kernel-consumer/kernel-consumer.c
> index 65dcce4..a8abcd7 100644
> --- a/src/common/kernel-consumer/kernel-consumer.c
> +++ b/src/common/kernel-consumer/kernel-consumer.c
> @@ -1085,15 +1085,27 @@ static int get_index_values(struct ctf_packet_index *index, int infd)
>
>         ret = kernctl_get_instance_id(infd, &index->stream_instance_id);
>         if (ret < 0) {
> -               PERROR("kernctl_get_instance_id");
> -               goto error;
> +               if (ret == -ENOTTY) {
> +                       /* Command not implemented by lttng-modules. */
> +                       index->stream_instance_id = -1ULL;
> +                       ret = 0;
> +               } else {
> +                       PERROR("kernctl_get_instance_id");
> +                       goto error;
> +               }
>         }
>         index->stream_instance_id = htobe64(index->stream_instance_id);
>
>         ret = kernctl_get_sequence_number(infd, &index->packet_seq_num);
>         if (ret < 0) {
> -               PERROR("kernctl_get_sequence_number");
> -               goto error;
> +               if (ret == -ENOTTY) {
> +                       /* Command not implemented by lttng-modules. */
> +                       index->packet_seq_num = -1ULL;
> +                       ret = 0;
> +               } else {
> +                       PERROR("kernctl_get_sequence_number");
> +                       goto error;
> +               }
>         }
>         index->packet_seq_num = htobe64(index->packet_seq_num);
>
> @@ -1145,8 +1157,14 @@ int update_stream_stats(struct lttng_consumer_stream *stream)
>
>         ret = kernctl_get_sequence_number(stream->wait_fd, &seq);
>         if (ret < 0) {
> -               PERROR("kernctl_get_sequence_number");
> -               goto end;
> +               if (ret == -ENOTTY) {
> +                       /* Command not implemented by lttng-modules. */
> +                       seq = -1ULL;
> +                       ret = 0;
> +               } else {
> +                       PERROR("kernctl_get_sequence_number");
> +                       goto end;
> +               }
>         }
>
>         /*
> @@ -1205,6 +1223,14 @@ int metadata_stream_check_version(int infd, struct lttng_consumer_stream *stream
>
>         ret = kernctl_get_metadata_version(infd, &cur_version);
>         if (ret < 0) {
> +               if (ret == -ENOTTY) {
> +                       /*
> +                        * LTTng-modules does not implement this
> +                        * command.
> +                        */
> +                       ret = 0;
> +                       goto end;
> +               }
>                 ERR("Failed to get the metadata version");
>                 goto end;
>         }
> --
> 2.1.4
>



-- 
Jérémie Galarneau
EfficiOS Inc.
http://www.efficios.com