> 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>
> ---
>
> Notes:
> v4:
> - Fix possible out of bounds access
> - Added missing index increment
>
> doc/guides/prog_guide/power_man.rst | 9 ++--
> lib/power/rte_power_pmd_mgmt.c | 81 ++++++++++++++++++++++++++++-
> 2 files changed, 85 insertions(+), 5 deletions(-)
>
> diff --git a/doc/guides/prog_guide/power_man.rst
> b/doc/guides/prog_guide/power_man.rst
> index ec04a72108..94353ca012 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 drivers 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 fccfd236c2..2056996b9c 100644
> --- a/lib/power/rte_power_pmd_mgmt.c
> +++ b/lib/power/rte_power_pmd_mgmt.c
> @@ -124,6 +124,32 @@ queue_list_take(struct pmd_core_cfg *cfg, const union
> queue *q)
> return found;
> }
>
> +static inline int
> +get_monitor_addresses(struct pmd_core_cfg *cfg,
> + struct rte_power_monitor_cond *pmc, size_t len)
> +{
> + const struct queue_list_entry *qle;
> + size_t i = 0;
> + int ret;
> +
> + TAILQ_FOREACH(qle, &cfg->head, next) {
> + const union queue *q = &qle->queue;
> + struct rte_power_monitor_cond *cur;
> +
> + /* attempted out of bounds access */
> + if (i >= len) {
> + RTE_LOG(ERR, POWER, "Too many queues being
> monitored\n");
> + return -1;
> + }
> +
> + cur = &pmc[i++];
> + ret = rte_eth_get_monitor_addr(q->portid, q->qid, cur);
> + if (ret < 0)
> + return ret;
> + }
> + return 0;
> +}
> +
> static void
> calc_tsc(void)
> {
> @@ -190,6 +216,45 @@ lcore_can_sleep(struct pmd_core_cfg *cfg)
> return true;
> }
>
> +static uint16_t
> +clb_multiwait(uint16_t port_id __rte_unused, uint16_t qidx __rte_unused,
> + struct rte_mbuf **pkts __rte_unused, uint16_t nb_rx,
> + uint16_t max_pkts __rte_unused, void *arg)
> +{
> + const unsigned int lcore = rte_lcore_id();
> + struct queue_list_entry *queue_conf = arg;
> + struct pmd_core_cfg *lcore_conf;
> + const bool empty = nb_rx == 0;
> +
> + lcore_conf = &lcore_cfgs[lcore];
> +
> + /* early exit */
> + if (likely(!empty))
> + /* early exit */
> + queue_reset(lcore_conf, queue_conf);
> + else {
> + struct rte_power_monitor_cond pmc[RTE_MAX_ETHPORTS];
As discussed, I still think it needs to be pmc[lcore_conf->n_queues];
Or if VLA is not an option - alloca(), or dynamic lcore_conf->pmc[], or...
> + int ret;
> +
> + /* can this queue sleep? */
> + if (!queue_can_sleep(lcore_conf, queue_conf))
> + return nb_rx;
> +
> + /* can this lcore sleep? */
> + if (!lcore_can_sleep(lcore_conf))
> + return nb_rx;
> +
> + /* gather all monitoring conditions */
> + ret = get_monitor_addresses(lcore_conf, pmc, RTE_DIM(pmc));
> + if (ret < 0)
> + return nb_rx;
> +
> + rte_power_monitor_multi(pmc, lcore_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, void *arg)
> @@ -341,14 +406,19 @@ 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;
> }
> @@ -364,6 +434,13 @@ 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)
> @@ -428,7 +505,7 @@ 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
