[lttng-dev] [PATCH lttng-tools] Perform local data pending before checking data pending with relayd

[Jérémie Galarneau]

Merged in master, stable-2.11, stable-2.10, and stable-2.9.

Thanks,
Jérémie

On Mon, Sep 10, 2018 at 08:09:15PM -0400, Jonathan Rajotte wrote:
> Performing the data pending check in two phases, local and network,
> reduce the total number network operation needed.
> 
> Doing the local check first enable early return in cases where data is
> still pending locally.
> 
> Signed-off-by: Jonathan Rajotte <jonathan.rajotte-julien at efficios.com>
> ---
>  src/common/consumer/consumer.c | 52 ++++++++++++++++++----------------
>  1 file changed, 28 insertions(+), 24 deletions(-)
> 
> diff --git a/src/common/consumer/consumer.c b/src/common/consumer/consumer.c
> index 66f10c780..5a32c7e8b 100644
> --- a/src/common/consumer/consumer.c
> +++ b/src/common/consumer/consumer.c
> @@ -3734,19 +3734,6 @@ int consumer_data_pending(uint64_t id)
>  	/* Ease our life a bit */
>  	ht = consumer_data.stream_list_ht;
>  
> -	relayd = find_relayd_by_session_id(id);
> -	if (relayd) {
> -		/* Send init command for data pending. */
> -		pthread_mutex_lock(&relayd->ctrl_sock_mutex);
> -		ret = relayd_begin_data_pending(&relayd->control_sock,
> -				relayd->relayd_session_id);
> -		pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
> -		if (ret < 0) {
> -			/* Communication error thus the relayd so no data pending. */
> -			goto data_not_pending;
> -		}
> -	}
> -
>  	cds_lfht_for_each_entry_duplicate(ht->ht,
>  			ht->hash_fct(&id, lttng_ht_seed),
>  			ht->match_fct, &id,
> @@ -3769,9 +3756,27 @@ int consumer_data_pending(uint64_t id)
>  			}
>  		}
>  
> -		/* Relayd check */
> -		if (relayd) {
> -			pthread_mutex_lock(&relayd->ctrl_sock_mutex);
> +		pthread_mutex_unlock(&stream->lock);
> +	}
> +
> +	relayd = find_relayd_by_session_id(id);
> +	if (relayd) {
> +		unsigned int is_data_inflight = 0;
> +
> +		/* Send init command for data pending. */
> +		pthread_mutex_lock(&relayd->ctrl_sock_mutex);
> +		ret = relayd_begin_data_pending(&relayd->control_sock,
> +				relayd->relayd_session_id);
> +		if (ret < 0) {
> +			pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
> +			/* Communication error thus the relayd so no data pending. */
> +			goto data_not_pending;
> +		}
> +
> +		cds_lfht_for_each_entry_duplicate(ht->ht,
> +				ht->hash_fct(&id, lttng_ht_seed),
> +				ht->match_fct, &id,
> +				&iter.iter, stream, node_session_id.node) {
>  			if (stream->metadata_flag) {
>  				ret = relayd_quiescent_control(&relayd->control_sock,
>  						stream->relayd_stream_id);
> @@ -3780,20 +3785,19 @@ int consumer_data_pending(uint64_t id)
>  						stream->relayd_stream_id,
>  						stream->next_net_seq_num - 1);
>  			}
> -			pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
>  			if (ret == 1) {
> +				pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
>  				pthread_mutex_unlock(&stream->lock);
>  				goto data_pending;
>  			}
> +			if (ret < 0) {
> +				pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
> +				pthread_mutex_unlock(&stream->lock);
> +				goto data_not_pending;
> +			}
>  		}
> -		pthread_mutex_unlock(&stream->lock);
> -	}
>  
> -	if (relayd) {
> -		unsigned int is_data_inflight = 0;
> -
> -		/* Send init command for data pending. */
> -		pthread_mutex_lock(&relayd->ctrl_sock_mutex);
> +		/* Send end command for data pending. */
>  		ret = relayd_end_data_pending(&relayd->control_sock,
>  				relayd->relayd_session_id, &is_data_inflight);
>  		pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
> -- 
> 2.17.1
>