Re: [PATCH] eventdev/timer: move buffer flush call

[Jerin Jacob <jerinjacobk@gmail.com>]

On Thu, Apr 13, 2023 at 1:26 AM Erik Gabriel Carrillo
<erik.g.carrillo@intel.com> wrote:
>
> The SW event timer adapter attempts to flush its event buffer on every
> adapter tick. If events remain in the buffer after the attempt, another
> attempt to flush won't occur until the next adapter tick, which delays
> the enqueue of those events to the event device unecessarily.

typo: unecessarily


Updated the git commit as follows and applied to
dpdk-next-net-eventdev/for-main. Thanks

    eventdev/timer: fix buffer flush

    The SW event timer adapter attempts to flush its event buffer on every
    adapter tick. If events remain in the buffer after the attempt, another
    attempt to flush won't occur until the next adapter tick, which delays
    the enqueue of those events to the event device unnecessarily.

    Move the buffer flush call so that it happens with every invocation of
    the service function, rather than on every adapter tick, to avoid the
    delay.

    Fixes: cc7b73ea9e3b ("eventdev: add new software timer adapter")
    Cc: stable@dpdk.org

    Signed-off-by: Erik Gabriel Carrillo <erik.g.carrillo@intel.com>

> Move the buffer flush call so that it happens with every invocation of
> the service function, rather than on every adapter tick, to avoid the
> delay.
>
> Fixes: cc7b73ea9e3b ("eventdev: add new software timer adapter")
> Cc: stable@dpdk.org
>
> Signed-off-by: Erik Gabriel Carrillo <erik.g.carrillo@intel.com>
> ---
>  lib/eventdev/rte_event_timer_adapter.c | 17 +++++++++--------
>  1 file changed, 9 insertions(+), 8 deletions(-)
>
> diff --git a/lib/eventdev/rte_event_timer_adapter.c b/lib/eventdev/rte_event_timer_adapter.c
> index 23eb1d4a7d..427c4c6287 100644
> --- a/lib/eventdev/rte_event_timer_adapter.c
> +++ b/lib/eventdev/rte_event_timer_adapter.c
> @@ -855,17 +855,18 @@ swtim_service_func(void *arg)
>                                      sw->n_expired_timers);
>                 sw->n_expired_timers = 0;
>
> -               event_buffer_flush(&sw->buffer,
> -                                  adapter->data->event_dev_id,
> -                                  adapter->data->event_port_id,
> -                                  &nb_evs_flushed,
> -                                  &nb_evs_invalid);
> -
> -               sw->stats.ev_enq_count += nb_evs_flushed;
> -               sw->stats.ev_inv_count += nb_evs_invalid;
>                 sw->stats.adapter_tick_count++;
>         }
>
> +       event_buffer_flush(&sw->buffer,
> +                          adapter->data->event_dev_id,
> +                          adapter->data->event_port_id,
> +                          &nb_evs_flushed,
> +                          &nb_evs_invalid);
> +
> +       sw->stats.ev_enq_count += nb_evs_flushed;
> +       sw->stats.ev_inv_count += nb_evs_invalid;
> +
>         rte_event_maintain(adapter->data->event_dev_id,
>                            adapter->data->event_port_id, 0);
>
> --
> 2.23.0
>