[lttng-dev] [PATCH lttng-tools 1/3 master, 2.10-rc] Fix: discard event/lost packet counters

[Jérémie Galarneau]

Merged in master, stable-2.10, stable-2.9, and stable-2.8.

Thanks!
Jérémie

On 26 May 2017 at 12:14, Mathieu Desnoyers
<mathieu.desnoyers at efficios.com> wrote:
> For per-pid buffers, we need to sum the counters for each application.
>
> For per-uid buffers, if no application has launched yet, it should not
> be considered as an error (which stops iteration on all other channels),
> but rather as values of 0.
>
> Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
> ---
>  src/bin/lttng-sessiond/ust-app.c | 35 ++++++++++++++++++++++++-----------
>  1 file changed, 24 insertions(+), 11 deletions(-)
>
> diff --git a/src/bin/lttng-sessiond/ust-app.c b/src/bin/lttng-sessiond/ust-app.c
> index d292779..8176d4d 100644
> --- a/src/bin/lttng-sessiond/ust-app.c
> +++ b/src/bin/lttng-sessiond/ust-app.c
> @@ -6083,21 +6083,24 @@ int ust_app_uid_get_channel_runtime_stats(uint64_t ust_session_id,
>         int ret;
>         uint64_t consumer_chan_key;
>
> +       *discarded = 0;
> +       *lost = 0;
> +
>         ret = buffer_reg_uid_consumer_channel_key(
>                         buffer_reg_uid_list, ust_session_id,
>                         uchan_id, &consumer_chan_key);
>         if (ret < 0) {
> +               /* Not found */
> +               ret = 0;
>                 goto end;
>         }
>
>         if (overwrite) {
>                 ret = consumer_get_lost_packets(ust_session_id,
>                                 consumer_chan_key, consumer, lost);
> -               *discarded = 0;
>         } else {
>                 ret = consumer_get_discarded_events(ust_session_id,
>                                 consumer_chan_key, consumer, discarded);
> -               *lost = 0;
>         }
>
>  end:
> @@ -6116,10 +6119,13 @@ int ust_app_pid_get_channel_runtime_stats(struct ltt_ust_session *usess,
>         struct ust_app_session *ua_sess;
>         struct ust_app_channel *ua_chan;
>
> +       *discarded = 0;
> +       *lost = 0;
> +
>         rcu_read_lock();
>         /*
> -        * Iterate over every registered applications, return when we
> -        * found one in the right session and channel.
> +        * Iterate over every registered applications. Sum counters for
> +        * all applications containing requested session and channel.
>          */
>         cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
>                 struct lttng_ht_iter uiter;
> @@ -6138,19 +6144,26 @@ int ust_app_pid_get_channel_runtime_stats(struct ltt_ust_session *usess,
>                 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
>
>                 if (overwrite) {
> +                       uint64_t _lost;
> +
>                         ret = consumer_get_lost_packets(usess->id, ua_chan->key,
> -                                       consumer, lost);
> -                       *discarded = 0;
> -                       goto end;
> +                                       consumer, &_lost);
> +                       if (ret < 0) {
> +                               break;
> +                       }
> +                       (*lost) += _lost;
>                 } else {
> +                       uint64_t _discarded;
> +
>                         ret = consumer_get_discarded_events(usess->id,
> -                                       ua_chan->key, consumer, discarded);
> -                       *lost = 0;
> -                       goto end;
> +                                       ua_chan->key, consumer, &_discarded);
> +                       if (ret < 0) {
> +                               break;
> +                       }
> +                       (*discarded) += _discarded;
>                 }
>         }
>
> -end:
>         rcu_read_unlock();
>         return ret;
>  }
> --
> 2.1.4
>



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