> Use the new multi-monitor intrinsic to allow monitoring multiple ethdev
> Rx queues while entering the energy efficient power state. The multi
> version will be used unconditionally if supported, and the UMWAIT one
> will only be used when multi-monitor is not supported by the hardware.
>
> Signed-off-by: Anatoly Burakov <anatoly.bura...@intel.com>
> ---
> doc/guides/prog_guide/power_man.rst | 9 ++--
> lib/power/rte_power_pmd_mgmt.c | 76 ++++++++++++++++++++++++++++-
> 2 files changed, 80 insertions(+), 5 deletions(-)
>
> diff --git a/doc/guides/prog_guide/power_man.rst
> b/doc/guides/prog_guide/power_man.rst
> index fac2c19516..3245a5ebed 100644
> --- a/doc/guides/prog_guide/power_man.rst
> +++ b/doc/guides/prog_guide/power_man.rst
> @@ -221,13 +221,16 @@ power saving whenever empty poll count reaches a
> certain number.
> The "monitor" mode is only supported in the following configurations and
> scenarios:
>
> * If ``rte_cpu_get_intrinsics_support()`` function indicates that
> + ``rte_power_monitor_multi()`` function is supported by the platform, then
> + monitoring multiple Ethernet Rx queues for traffic will be supported.
> +
> +* If ``rte_cpu_get_intrinsics_support()`` function indicates that only
> ``rte_power_monitor()`` is supported by the platform, then monitoring will
> be
> limited to a mapping of 1 core 1 queue (thus, each Rx queue will have to be
> monitored from a different lcore).
>
> -* If ``rte_cpu_get_intrinsics_support()`` function indicates that the
> - ``rte_power_monitor()`` function is not supported, then monitor mode will
> not
> - be supported.
> +* If ``rte_cpu_get_intrinsics_support()`` function indicates that neither of
> the
> + two monitoring functions are supported, then monitor mode will not be
> supported.
>
> * Not all Ethernet devices support monitoring, even if the underlying
> platform may support the necessary CPU instructions. Please refer to
> diff --git a/lib/power/rte_power_pmd_mgmt.c b/lib/power/rte_power_pmd_mgmt.c
> index 7762cd39b8..aab2d4f1ee 100644
> --- a/lib/power/rte_power_pmd_mgmt.c
> +++ b/lib/power/rte_power_pmd_mgmt.c
> @@ -155,6 +155,24 @@ queue_list_remove(struct pmd_core_cfg *cfg, const union
> queue *q)
> return 0;
> }
>
> +static inline int
> +get_monitor_addresses(struct pmd_core_cfg *cfg,
> + struct rte_power_monitor_cond *pmc)
> +{
> + const struct queue_list_entry *qle;
> + size_t i = 0;
> + int ret;
> +
> + TAILQ_FOREACH(qle, &cfg->head, next) {
> + struct rte_power_monitor_cond *cur = &pmc[i];
Looks like you never increment 'i' value inside that function.
Also it probably will be safer to add 'num' parameter to check that
we will never over-run pmc[] boundaries.
> + const union queue *q = &qle->queue;
> + ret = rte_eth_get_monitor_addr(q->portid, q->qid, cur);
> + if (ret < 0)
> + return ret;
> + }
> + return 0;
> +}
> +
> static void
> calc_tsc(void)
> {
> @@ -183,6 +201,48 @@ calc_tsc(void)
> }
> }
>
> +static uint16_t
> +clb_multiwait(uint16_t port_id, uint16_t qidx,
> + struct rte_mbuf **pkts __rte_unused, uint16_t nb_rx,
> + uint16_t max_pkts __rte_unused, void *addr __rte_unused)
> +{
> + const unsigned int lcore = rte_lcore_id();
> + const union queue q = {.portid = port_id, .qid = qidx};
> + const bool empty = nb_rx == 0;
> + struct pmd_core_cfg *q_conf;
> +
> + q_conf = &lcore_cfg[lcore];
> +
> + /* early exit */
> + if (likely(!empty)) {
> + q_conf->empty_poll_stats = 0;
> + } else {
> + /* do we care about this particular queue? */
> + if (!queue_is_power_save(q_conf, &q))
> + return nb_rx;
I still don't understand the need of 'special' power_save queue here...
Why we can't just have a function:
get_number_of_queues_whose_sequential_empty_polls_less_then_threshold(struct
pmd_core_cfg *lcore_cfg),
and then just:
/* all queues have at least EMPTYPOLL_MAX sequential empty polls */
if
(get_number_of_queues_whose_sequential_empty_polls_less_then_threshold(q_conf)
== 0) {
/* go into power-save mode here */
}
> +
> + /*
> + * we can increment unconditionally here because if there were
> + * non-empty polls in other queues assigned to this core, we
> + * dropped the counter to zero anyway.
> + */
> + q_conf->empty_poll_stats++;
> + if (unlikely(q_conf->empty_poll_stats > EMPTYPOLL_MAX)) {
> + struct rte_power_monitor_cond pmc[RTE_MAX_ETHPORTS];
I think you need here:
struct rte_power_monitor_cond pmc[q_conf->n_queues];
> + uint16_t ret;
> +
> + /* gather all monitoring conditions */
> + ret = get_monitor_addresses(q_conf, pmc);
> +
> + if (ret == 0)
> + rte_power_monitor_multi(pmc,
> + q_conf->n_queues, UINT64_MAX);
> + }
> + }
> +
> + return nb_rx;
> +}
> +
> static uint16_t
> clb_umwait(uint16_t port_id, uint16_t qidx, struct rte_mbuf **pkts
> __rte_unused,
> uint16_t nb_rx, uint16_t max_pkts __rte_unused,
> @@ -348,14 +408,19 @@ static int
> check_monitor(struct pmd_core_cfg *cfg, const union queue *qdata)
> {
> struct rte_power_monitor_cond dummy;
> + bool multimonitor_supported;
>
> /* check if rte_power_monitor is supported */
> if (!global_data.intrinsics_support.power_monitor) {
> RTE_LOG(DEBUG, POWER, "Monitoring intrinsics are not
> supported\n");
> return -ENOTSUP;
> }
> + /* check if multi-monitor is supported */
> + multimonitor_supported =
> + global_data.intrinsics_support.power_monitor_multi;
>
> - if (cfg->n_queues > 0) {
> + /* if we're adding a new queue, do we support multiple queues? */
> + if (cfg->n_queues > 0 && !multimonitor_supported) {
> RTE_LOG(DEBUG, POWER, "Monitoring multiple queues is not
> supported\n");
> return -ENOTSUP;
> }
> @@ -371,6 +436,13 @@ check_monitor(struct pmd_core_cfg *cfg, const union
> queue *qdata)
> return 0;
> }
>
> +static inline rte_rx_callback_fn
> +get_monitor_callback(void)
> +{
> + return global_data.intrinsics_support.power_monitor_multi ?
> + clb_multiwait : clb_umwait;
> +}
> +
> int
> rte_power_ethdev_pmgmt_queue_enable(unsigned int lcore_id, uint16_t port_id,
> uint16_t queue_id, enum rte_power_pmd_mgmt_type mode)
> @@ -434,7 +506,7 @@ rte_power_ethdev_pmgmt_queue_enable(unsigned int
> lcore_id, uint16_t port_id,
> if (ret < 0)
> goto end;
>
> - clb = clb_umwait;
> + clb = get_monitor_callback();
> break;
> case RTE_POWER_MGMT_TYPE_SCALE:
> /* check if we can add a new queue */
> --
> 2.25.1
