[dpdk-dev] [PATCH v4 1/2] lib/librte_power: traffic pattern aware power control

[Hunt, David]

On 26/6/2018 12:40 PM, Radu Nicolau wrote:
> From: Liang Ma <liang.j.ma at intel.com>
>
> 1. Abstract
>
> For packet processing workloads such as DPDK polling is continuous.
> This means CPU cores always show 100% busy independent of how much work
> those cores are doing. It is critical to accurately determine how busy
> a core is hugely important for the following reasons:
>
>     * No indication of overload conditions
>
>     * User do not know how much real load is on a system meaning resulted in
>       wasted energy as no power management is utilized
>
> Tried and failed schemes include calculating the cycles required from
> the load on the core, in other words the busyness. For example,
> how many cycles it costs to handle each packet and determining the
> frequency cost per core. Due to the varying nature of traffic, types of
> frames and cost in cycles to process, this mechanism becomes complex
> quickly where a simple scheme is required to solve the problems.
>
> 2. Proposed solution
>
> For all polling mechanism, the proposed solution focus on how many times
> empty poll executed instead of calculating how many cycles it cost to
> handle each packet. The less empty poll number means current core is busy
> with processing workload, therefore,  the higher frequency is needed. The
> high empty poll number indicate current core has lots spare time,
> therefore, we can lower the frequency.
>
> 2.1 Power state definition:
>
> 	LOW:  the frequency is used for purge mode.
>
> 	MED:  the frequency is used to process modest traffic workload.
>
> 	HIGH: the frequency is used to process busy traffic workload.
>
> 2.2 There are two phases to establish the power management system:
>
> 	a.Initialization/Training phase. There is no traffic pass-through,
> 	  the system will test average empty poll numbers  with
> 	  LOW/MED/HIGH  power state. Those average empty poll numbers
> 	  will be the baseline
> 	  for the normal phase. The system will collect all core's counter
> 	  every 100ms. The Training phase will take 5 seconds.
>
> 	b.Normal phase. When the real traffic pass-though, the system will
> 	  compare run-time empty poll moving average value with base line
> 	  then make decision to move to HIGH power state of MED  power
> 	  state. The system will collect all core's counter every 10ms.
>
> 3. Proposed  API
>
> 1.  rte_power_empty_poll_stat_init(void);
> which is used to initialize the power management system.
>   
> 2.  rte_power_empty_poll_stat_free(void);
> which is used to free the resource hold by power management system.
>   
> 3.  rte_power_empty_poll_stat_update(unsigned int lcore_id);
> which is used to update specific core empty poll counter, not thread safe
>   
> 4.  rte_power_poll_stat_update(unsigned int lcore_id, uint8_t nb_pkt);
> which is used to update specific core valid poll counter, not thread safe
>   
> 5.  rte_power_empty_poll_stat_fetch(unsigned int lcore_id);
> which is used to get specific core empty poll counter.
>   
> 6.  rte_power_poll_stat_fetch(unsigned int lcore_id);
> which is used to get specific core valid poll counter.
>
> 7.  rte_power_empty_poll_set_freq(enum freq_val index, uint32_t limit);
> which allow user customize the frequency of power state.
>
> 8.  rte_power_empty_poll_setup_timer(void);
> which is used to setup the timer/callback to process all above counter.
>
> ChangeLog:
> v2: fix some coding style issues
> v3: rename the filename, API name.
> v4: updated makefile and symbol list
>
> Signed-off-by: Liang Ma <liang.j.ma at intel.com>
> Signed-off-by: Radu Nicolau <radu.nicolau at intel.com>
> ---
>   lib/librte_power/Makefile               |   5 +-
>   lib/librte_power/meson.build            |   5 +-
>   lib/librte_power/rte_power_empty_poll.c | 521 ++++++++++++++++++++++++++++++++
>   lib/librte_power/rte_power_empty_poll.h | 202 +++++++++++++
>   lib/librte_power/rte_power_version.map  |  14 +-
>   5 files changed, 742 insertions(+), 5 deletions(-)
>   create mode 100644 lib/librte_power/rte_power_empty_poll.c
>   create mode 100644 lib/librte_power/rte_power_empty_poll.h
>
> diff --git a/lib/librte_power/Makefile b/lib/librte_power/Makefile
> index 6f85e88..9bec668 100644
> --- a/lib/librte_power/Makefile
> +++ b/lib/librte_power/Makefile
> @@ -7,7 +7,7 @@ include $(RTE_SDK)/mk/rte.vars.mk
>   LIB = librte_power.a
>   
>   CFLAGS += $(WERROR_FLAGS) -I$(SRCDIR) -O3 -fno-strict-aliasing
> -LDLIBS += -lrte_eal
> +LDLIBS += -lrte_eal -lrte_timer
>   
>   EXPORT_MAP := rte_power_version.map
>   
> @@ -16,8 +16,9 @@ LIBABIVER := 1
>   # all source are stored in SRCS-y
>   SRCS-$(CONFIG_RTE_LIBRTE_POWER) := rte_power.c power_acpi_cpufreq.c
>   SRCS-$(CONFIG_RTE_LIBRTE_POWER) += power_kvm_vm.c guest_channel.c
> +SRCS-$(CONFIG_RTE_LIBRTE_POWER) += rte_power_empty_poll.c
>   
>   # install this header file
> -SYMLINK-$(CONFIG_RTE_LIBRTE_POWER)-include := rte_power.h
> +SYMLINK-$(CONFIG_RTE_LIBRTE_POWER)-include := rte_power.h  rte_power_empty_poll.h
>   
>   include $(RTE_SDK)/mk/rte.lib.mk
> diff --git a/lib/librte_power/meson.build b/lib/librte_power/meson.build
> index 253173f..63957eb 100644
> --- a/lib/librte_power/meson.build
> +++ b/lib/librte_power/meson.build
> @@ -5,5 +5,6 @@ if host_machine.system() != 'linux'
>   	build = false
>   endif
>   sources = files('rte_power.c', 'power_acpi_cpufreq.c',
> -		'power_kvm_vm.c', 'guest_channel.c')
> -headers = files('rte_power.h')
> +		'power_kvm_vm.c', 'guest_channel.c',
> +		'rte_power_empty_poll.c')
> +headers = files('rte_power.h','rte_power_empty_poll.h')
> diff --git a/lib/librte_power/rte_power_empty_poll.c b/lib/librte_power/rte_power_empty_poll.c
> new file mode 100644
> index 0000000..923226b
> --- /dev/null
> +++ b/lib/librte_power/rte_power_empty_poll.c
> @@ -0,0 +1,521 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright(c) 2010-2018 Intel Corporation
> + */
> +
> +#include <string.h>
> +
> +#include <rte_lcore.h>
> +#include <rte_cycles.h>
> +#include <rte_atomic.h>
> +#include <rte_malloc.h>
> +
> +#include "rte_power.h"
> +#include "rte_power_empty_poll.h"
> +
> +#define INTERVALS_PER_SECOND 100     /* (10ms) */
> +#define SECONDS_TO_TRAIN_FOR  5
> +#define DEFAULT_MED_TO_HIGH_PERCENT_THRESHOLD 70
> +#define DEFAULT_HIGH_TO_MED_PERCENT_THRESHOLD 30
> +#define DEFAULT_CYCLES_PER_PACKET 800
> +
> +static struct ep_params *ep_params;
> +static uint32_t med_to_high_threshold = DEFAULT_MED_TO_HIGH_PERCENT_THRESHOLD;
> +static uint32_t high_to_med_threshold = DEFAULT_HIGH_TO_MED_PERCENT_THRESHOLD;
> +
> +static uint32_t avail_freqs[RTE_MAX_LCORE][NUM_FREQS];
> +
> +static uint32_t total_avail_freqs[RTE_MAX_LCORE];
> +
> +static uint32_t freq_index[NUM_FREQ];
> +
> +static uint32_t
> +get_freq_index(enum freq_val index)
> +{
> +	return freq_index[index];
> +}
> +
> +
> +static int
> +set_power_freq(int lcore_id, enum freq_val freq, bool specific_freq)
> +{
> +	int err = 0;
> +	uint32_t power_freq_index;
> +	if (!specific_freq)
> +		power_freq_index = get_freq_index(freq);
> +	else
> +		power_freq_index = freq;
> +
> +	err = rte_power_set_freq(lcore_id, power_freq_index);
> +
> +	return err;
> +}
> +
> +
> +static inline void __attribute__((always_inline))
> +exit_training_state(struct priority_worker *poll_stats)
> +{
> +	RTE_SET_USED(poll_stats);
> +}
> +
> +static inline void __attribute__((always_inline))
> +enter_training_state(struct priority_worker *poll_stats)
> +{
> +	poll_stats->iter_counter = 0;
> +	poll_stats->cur_freq = LOW;
> +	poll_stats->queue_state = TRAINING;
> +}
> +
> +static inline void __attribute__((always_inline))
> +enter_normal_state(struct priority_worker *poll_stats)
> +{
> +	/* Clear the averages arrays and strs */
> +	memset(poll_stats->edpi_av, 0, sizeof(poll_stats->edpi_av));
> +	poll_stats->ec = 0;
> +	memset(poll_stats->ppi_av, 0, sizeof(poll_stats->ppi_av));
> +	poll_stats->pc = 0;
> +
> +	poll_stats->cur_freq = MED;
> +	poll_stats->iter_counter = 0;
> +	poll_stats->threshold_ctr = 0;
> +	poll_stats->queue_state = MED_NORMAL;
> +	set_power_freq(poll_stats->lcore_id, MED, false);
> +
> +	/* Try here */
> +	poll_stats->thresh[MED].threshold_percent = med_to_high_threshold;
> +	poll_stats->thresh[HGH].threshold_percent = high_to_med_threshold;
> +}
> +
> +static inline void __attribute__((always_inline))
> +enter_busy_state(struct priority_worker *poll_stats)
> +{
> +	memset(poll_stats->edpi_av, 0, sizeof(poll_stats->edpi_av));
> +	poll_stats->ec = 0;
> +	memset(poll_stats->ppi_av, 0, sizeof(poll_stats->ppi_av));
> +	poll_stats->pc = 0;
> +
> +	poll_stats->cur_freq = HGH;
> +	poll_stats->iter_counter = 0;
> +	poll_stats->threshold_ctr = 0;
> +	poll_stats->queue_state = HGH_BUSY;
> +	set_power_freq(poll_stats->lcore_id, HGH, false);
> +}
> +
> +static inline void __attribute__((always_inline))
> +enter_purge_state(struct priority_worker *poll_stats)
> +{
> +	poll_stats->iter_counter = 0;
> +	poll_stats->queue_state = LOW_PURGE;
> +}
> +
> +static inline void __attribute__((always_inline))
> +set_state(struct priority_worker *poll_stats,
> +		enum queue_state new_state)
> +{
> +	enum queue_state old_state = poll_stats->queue_state;
> +	if (old_state != new_state) {
> +
> +		/* Call any old state exit functions */
> +		if (old_state == TRAINING)
> +			exit_training_state(poll_stats);
> +
> +		/* Call any new state entry functions */
> +		if (new_state == TRAINING)
> +			enter_training_state(poll_stats);
> +		if (new_state == MED_NORMAL)
> +			enter_normal_state(poll_stats);
> +		if (new_state == HGH_BUSY)
> +			enter_busy_state(poll_stats);
> +		if (new_state == LOW_PURGE)
> +			enter_purge_state(poll_stats);
> +	}
> +}
> +
> +
> +static void
> +update_training_stats(struct priority_worker *poll_stats,
> +		uint32_t freq,
> +		bool specific_freq,
> +		uint32_t max_train_iter)
> +{
> +	RTE_SET_USED(specific_freq);
> +
> +	char pfi_str[32];
> +	uint64_t p0_empty_deq;
> +
> +	sprintf(pfi_str, "%02d", freq);
> +
> +	if (poll_stats->cur_freq == freq &&
> +			poll_stats->thresh[freq].trained == false) {
> +		if (poll_stats->thresh[freq].cur_train_iter == 0) {
> +
> +			set_power_freq(poll_stats->lcore_id,
> +					freq, specific_freq);
> +
> +			poll_stats->empty_dequeues_prev =
> +				poll_stats->empty_dequeues;
> +
> +			poll_stats->thresh[freq].cur_train_iter++;
> +
> +			return;
> +		} else if (poll_stats->thresh[freq].cur_train_iter
> +				<= max_train_iter) {
> +
> +			p0_empty_deq = poll_stats->empty_dequeues -
> +				poll_stats->empty_dequeues_prev;
> +
> +			poll_stats->empty_dequeues_prev =
> +				poll_stats->empty_dequeues;
> +
> +			poll_stats->thresh[freq].base_edpi += p0_empty_deq;
> +			poll_stats->thresh[freq].cur_train_iter++;
> +
> +		} else {
> +			if (poll_stats->thresh[freq].trained == false) {
> +				poll_stats->thresh[freq].base_edpi =
> +					poll_stats->thresh[freq].base_edpi /
> +					max_train_iter;
> +
> +				/* Add on a factor of 0.05%, this should remove any */
> +				/* false negatives when the system is 0% busy */
> +				poll_stats->thresh[freq].base_edpi +=
> +					poll_stats->thresh[freq].base_edpi / 2000;
> +
> +				poll_stats->thresh[freq].trained = true;
> +				poll_stats->cur_freq++;
> +
> +			}
> +		}
> +	}
> +}
> +
> +static inline uint32_t __attribute__((always_inline))
> +update_stats(struct priority_worker *poll_stats)
> +{
> +	uint64_t tot_edpi = 0, tot_ppi = 0;
> +	uint32_t j, percent;
> +
> +	struct priority_worker *s = poll_stats;
> +
> +	uint64_t cur_edpi = s->empty_dequeues - s->empty_dequeues_prev;
> +
> +	s->empty_dequeues_prev = s->empty_dequeues;
> +
> +	uint64_t ppi = s->num_dequeue_pkts - s->num_dequeue_pkts_prev;
> +
> +	s->num_dequeue_pkts_prev = s->num_dequeue_pkts;
> +
> +	if (s->thresh[s->cur_freq].base_edpi < cur_edpi)
> +		return 1000UL; /* Value to make us fail */
> +
> +	s->edpi_av[s->ec++ % BINS_AV] = cur_edpi;
> +	s->ppi_av[s->pc++ % BINS_AV] = ppi;
> +
> +	for (j = 0; j < BINS_AV; j++) {
> +		tot_edpi += s->edpi_av[j];
> +		tot_ppi += s->ppi_av[j];
> +	}
> +
> +	tot_edpi = tot_edpi / BINS_AV;
> +
> +	percent = 100 - (uint32_t)((float)tot_edpi /
> +			(float)s->thresh[s->cur_freq].base_edpi * 100);
> +
> +	return (uint32_t)percent;
> +}
> +
> +
> +static inline void  __attribute__((always_inline))
> +update_stats_normal(struct priority_worker *poll_stats)
> +{
> +	uint32_t percent;
> +
> +	if (poll_stats->thresh[poll_stats->cur_freq].base_edpi == 0)
> +		return;
> +
> +	percent = update_stats(poll_stats);
> +
> +	if (percent > 100)
> +		return;
> +
> +	if (poll_stats->cur_freq == LOW)
> +		RTE_LOG(INFO, POWER, "Purge Mode is not supported\n");
> +	else if (poll_stats->cur_freq == MED) {
> +
> +		if (percent >
> +			poll_stats->thresh[poll_stats->cur_freq].threshold_percent) {
> +
> +			if (poll_stats->threshold_ctr < INTERVALS_PER_SECOND)
> +				poll_stats->threshold_ctr++;
> +			else
> +				set_state(poll_stats, HGH_BUSY);
> +
> +		} else {
> +			/* reset */
> +			poll_stats->threshold_ctr = 0;
> +		}
> +
> +	} else if (poll_stats->cur_freq == HGH) {
> +
> +		if (percent <
> +			poll_stats->thresh[poll_stats->cur_freq].threshold_percent) {
> +
> +			if (poll_stats->threshold_ctr < INTERVALS_PER_SECOND)
> +				poll_stats->threshold_ctr++;
> +			else
> +				set_state(poll_stats, MED_NORMAL);
> +		} else
> +			/* reset */
> +			poll_stats->threshold_ctr = 0;
> +
> +
> +	}
> +}
> +
> +static int
> +empty_poll_trainning(struct priority_worker *poll_stats,
> +		uint32_t max_train_iter)
> +{
> +
> +	if (poll_stats->iter_counter < INTERVALS_PER_SECOND) {
> +		poll_stats->iter_counter++;
> +		return 0;
> +	}
> +
> +
> +	update_training_stats(poll_stats,
> +			LOW,
> +			false,
> +			max_train_iter);
> +
> +	update_training_stats(poll_stats,
> +			MED,
> +			false,
> +			max_train_iter);
> +
> +	update_training_stats(poll_stats,
> +			HGH,
> +			false,
> +			max_train_iter);
> +
> +
> +	if (poll_stats->thresh[LOW].trained == true
> +			&& poll_stats->thresh[MED].trained == true
> +			&& poll_stats->thresh[HGH].trained == true) {
> +
> +		set_state(poll_stats, MED_NORMAL);
> +
> +		RTE_LOG(INFO, POWER, "Training is Complete for %d\n",
> +				poll_stats->lcore_id);
> +	}
> +
> +	return 0;
> +}
> +
> +static void
> +empty_poll_detection(struct rte_timer *tim,
> +		void *arg)
> +{
> +
> +	uint32_t i;
> +
> +	struct priority_worker *poll_stats;
> +
> +	RTE_SET_USED(tim);
> +
> +	RTE_SET_USED(arg);
> +
> +	for (i = 0; i < NUM_NODES; i++) {
> +
> +		poll_stats = &(ep_params->wrk_data.wrk_stats[i]);
> +
> +		if (rte_lcore_is_enabled(poll_stats->lcore_id) == 0)
> +			continue;
> +
> +		switch (poll_stats->queue_state) {
> +		case(TRAINING):
> +			empty_poll_trainning(poll_stats,
> +					ep_params->max_train_iter);
> +			break;
> +
> +		case(HGH_BUSY):
> +		case(MED_NORMAL):
> +			update_stats_normal(poll_stats);
> +
> +			break;
> +
> +		case(LOW_PURGE):
> +			break;
> +		default:
> +			break;
> +
> +		}
> +
> +	}
> +
> +}
> +
> +int
> +rte_power_empty_poll_stat_init(void)
> +{
> +	uint32_t i;
> +	/* Allocate the ep_params structure */
> +	ep_params = rte_zmalloc_socket(NULL,
> +			sizeof(struct ep_params),
> +			0,
> +			rte_socket_id());
> +
> +	if (!ep_params)
> +		rte_panic("Cannot allocate heap memory for ep_params "
> +				"for socket %d\n", rte_socket_id());
> +
> +	freq_index[LOW] = 14;
> +	freq_index[MED] = 9;
> +	freq_index[HGH] = 1;
> +
> +	RTE_LOG(INFO, POWER, "Initialize the Empty Poll\n");
> +
> +	/* 5 seconds worth of training */
> +	ep_params->max_train_iter = INTERVALS_PER_SECOND * SECONDS_TO_TRAIN_FOR;
> +
> +	struct stats_data *w = &ep_params->wrk_data;
> +
> +	/* initialize all wrk_stats state */
> +	for (i = 0; i < NUM_NODES; i++) {
> +
> +		if (rte_lcore_is_enabled(i) == 0)
> +			continue;
> +
> +		set_state(&w->wrk_stats[i], TRAINING);
> +		/*init the freqs table */
> +		total_avail_freqs[i] = rte_power_freqs(i,
> +				avail_freqs[i],
> +				NUM_FREQS);
> +
> +		if (get_freq_index(LOW) > total_avail_freqs[i])
> +			return -1;
> +
> +	}
> +
> +
> +	return 0;
> +}
> +
> +void
> +rte_power_empty_poll_stat_free(void)
> +{
> +
> +	RTE_LOG(INFO, POWER, "Close the Empty Poll\n");
> +
> +	if (ep_params != NULL)
> +		rte_free(ep_params);
> +}
> +
> +int
> +rte_power_empty_poll_stat_update(unsigned int lcore_id)
> +{
> +	struct priority_worker *poll_stats;
> +
> +	if (lcore_id >= NUM_NODES)
> +		return -1;
> +
> +	poll_stats = &(ep_params->wrk_data.wrk_stats[lcore_id]);
> +
> +	if (poll_stats->lcore_id == 0)
> +		poll_stats->lcore_id = lcore_id;
> +
> +	poll_stats->empty_dequeues++;
> +
> +	return 0;
> +}
> +
> +int
> +rte_power_poll_stat_update(unsigned int lcore_id, uint8_t nb_pkt)
> +{
> +
> +	struct priority_worker *poll_stats;
> +
> +	if (lcore_id >= NUM_NODES)
> +		return -1;
> +
> +	poll_stats = &(ep_params->wrk_data.wrk_stats[lcore_id]);
> +
> +	if (poll_stats->lcore_id == 0)
> +		poll_stats->lcore_id = lcore_id;
> +
> +	poll_stats->num_dequeue_pkts += nb_pkt;
> +
> +	return 0;
> +}
> +
> +
> +uint64_t
> +rte_power_empty_poll_stat_fetch(unsigned int lcore_id)
> +{
> +	struct priority_worker *poll_stats;
> +
> +	if (lcore_id >= NUM_NODES)
> +		return -1;
> +
> +	poll_stats = &(ep_params->wrk_data.wrk_stats[lcore_id]);
> +
> +	if (poll_stats->lcore_id == 0)
> +		poll_stats->lcore_id = lcore_id;
> +
> +	return poll_stats->empty_dequeues;
> +}
> +
> +uint64_t
> +rte_power_poll_stat_fetch(unsigned int lcore_id)
> +{
> +	struct priority_worker *poll_stats;
> +
> +	if (lcore_id >= NUM_NODES)
> +		return -1;
> +
> +	poll_stats = &(ep_params->wrk_data.wrk_stats[lcore_id]);
> +
> +	if (poll_stats->lcore_id == 0)
> +		poll_stats->lcore_id = lcore_id;
> +
> +	return poll_stats->num_dequeue_pkts;
> +}
> +
> +void
> +rte_power_empty_poll_set_freq(enum freq_val index, uint32_t limit)
> +{
> +	switch (index) {
> +
> +	case LOW:
> +		freq_index[LOW] = limit;
> +		break;
> +
> +	case MED:
> +		freq_index[MED] = limit;
> +		break;
> +
> +	case HGH:
> +		freq_index[HGH] = limit;
> +		break;
> +	default:
> +		break;
> +	}
> +}
> +
> +void
> +rte_power_empty_poll_setup_timer(void)
> +{
> +	int lcore_id = rte_lcore_id();
> +	uint64_t hz = rte_get_timer_hz();
> +
> +	struct  ep_params *ep_ptr = ep_params;
> +
> +	ep_ptr->interval_ticks = hz / INTERVALS_PER_SECOND;
> +
> +	rte_timer_reset_sync(&ep_ptr->timer0,
> +			ep_ptr->interval_ticks,
> +			PERIODICAL,
> +			lcore_id,
> +			empty_poll_detection,
> +			(void *)ep_ptr);
> +
> +}
> diff --git a/lib/librte_power/rte_power_empty_poll.h b/lib/librte_power/rte_power_empty_poll.h
> new file mode 100644
> index 0000000..c814784
> --- /dev/null
> +++ b/lib/librte_power/rte_power_empty_poll.h
> @@ -0,0 +1,202 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright(c) 2010-2018 Intel Corporation
> + */
> +
> +#ifndef _RTE_EMPTY_POLL_H
> +#define _RTE_EMPTY_POLL_H
> +
> +/**
> + * @file
> + * RTE Power Management
> + */
> +#include <stdint.h>
> +#include <stdbool.h>
> +#include <sys/queue.h>
> +
> +#include <rte_common.h>
> +#include <rte_byteorder.h>
> +#include <rte_log.h>
> +#include <rte_string_fns.h>
> +#include <rte_power.h>
> +#include <rte_timer.h>
> +
> +#ifdef __cplusplus
> +extern "C" {
> +#endif
> +
> +#define NUM_FREQS 20
> +
> +#define BINS_AV 4 /* Has to be ^2 */
> +
> +#define DROP (NUM_DIRECTIONS * NUM_DEVICES)
> +
> +#define NUM_PRIORITIES          2
> +
> +#define NUM_NODES         31 /* Any reseanable prime number should work*/
> +
> +/* Processor Power State */
> +enum freq_val {
> +	LOW,
> +	MED,
> +	HGH,
> +	NUM_FREQ = NUM_FREQS
> +};
> +
> +
> +/* Queue Polling State */
> +enum queue_state {
> +	TRAINING, /* NO TRAFFIC */
> +	MED_NORMAL,   /* MED */
> +	HGH_BUSY,     /* HIGH */
> +	LOW_PURGE,    /* LOW */
> +};
> +
> +/* Queue Stats */
> +struct freq_threshold {
> +
> +	uint64_t base_edpi;
> +	bool trained;
> +	uint32_t threshold_percent;
> +	uint32_t cur_train_iter;
> +};
> +
> +/* Each Worder Tread Empty Poll Stats */
> +struct priority_worker {
> +
> +	/* Current dequeue and throughput counts */
> +	/* These 2 are written to by the worker threads */
> +	/* So keep them on their own cache line */
> +	uint64_t empty_dequeues;
> +	uint64_t num_dequeue_pkts;
> +
> +	enum queue_state queue_state;
> +
> +	uint64_t empty_dequeues_prev;
> +	uint64_t num_dequeue_pkts_prev;
> +
> +	/* Used for training only */
> +	struct freq_threshold thresh[NUM_FREQ];
> +	enum freq_val cur_freq;
> +
> +	/* bucket arrays to calculate the averages */
> +	uint64_t edpi_av[BINS_AV];
> +	uint32_t  ec;
> +	uint64_t ppi_av[BINS_AV];
> +	uint32_t  pc;
> +
> +	uint32_t lcore_id;
> +	uint32_t iter_counter;
> +	uint32_t threshold_ctr;
> +	uint32_t display_ctr;
> +	uint8_t  dev_id;
> +
> +} __rte_cache_aligned;
> +
> +
> +struct stats_data {
> +
> +	struct priority_worker wrk_stats[NUM_NODES];
> +
> +	/* flag to stop rx threads processing packets until training over */
> +	bool start_rx;
> +
> +};
> +
> +/* Empty Poll Parameters */
> +struct ep_params {
> +
> +	/* Timer related stuff */
> +	uint64_t interval_ticks;
> +	uint32_t max_train_iter;
> +
> +	struct rte_timer timer0;
> +	struct stats_data wrk_data;
> +};
> +
> +
> +/**
> + * Initialize the power management system.
> + *
> + * @param void
> + *
> + * @return
> + *  - 0 on success.
> + *  - Negative on error.
> + */
> +int rte_power_empty_poll_stat_init(void);
> +
> +/**
> + * Free the resource hold by power management system.
> + */
> +void rte_power_empty_poll_stat_free(void);
> +
> +/**
> + * Update specific core empty poll counter
> + * It's not thread safe.
> + *
> + * @param lcore_id
> + *  lcore id
> + *
> + * @return
> + *  - 0 on success.
> + *  - Negative on error.
> + */
> +int rte_power_empty_poll_stat_update(unsigned int lcore_id);
> +
> +/**
> + * Update specific core valid poll counter, not thread safe.
> + *
> + * @param lcore_id
> + *  lcore id.
> + * @param nb_pkt
> + *  The packet number of one valid poll.
> + *
> + * @return
> + *  - 0 on success.
> + *  - Negative on error.
> + */
> +int rte_power_poll_stat_update(unsigned int lcore_id, uint8_t nb_pkt);
> +
> +/**
> + * Fetch specific core empty poll counter.
> + *
> + * @param lcore_id
> + *  lcore id
> + *
> + * @return
> + *  Current lcore empty poll counter value.
> + */
> +uint64_t rte_power_empty_poll_stat_fetch(unsigned int lcore_id);
> +
> +/**
> + * Fetch specific core valid poll counter.
> + *
> + * @param lcore_id
> + *  lcore id
> + *
> + * @return
> + *  Current lcore valid poll counter value.
> + */
> +uint64_t rte_power_poll_stat_fetch(unsigned int lcore_id);
> +
> +/**
> + * Allow user customize the index of power state.
> + *
> + * @param  index
> + *  The type of the queue power state
> + * @param  limit
> + *  The processor P-state offset value for that power state.
> + */
> +void rte_power_empty_poll_set_freq(enum freq_val index, uint32_t limit);
> +
> +/**
> + * Setup the timer/callback to process empty poll counter.
> + * Default timer resolution is 10ms.
> + */
> +void rte_power_empty_poll_setup_timer(void);
> +
> +#ifdef __cplusplus
> +}
> +#endif
> +
> +#endif
> diff --git a/lib/librte_power/rte_power_version.map b/lib/librte_power/rte_power_version.map
> index 96dc42e..8e393e0 100644
> --- a/lib/librte_power/rte_power_version.map
> +++ b/lib/librte_power/rte_power_version.map
> @@ -25,4 +25,16 @@ DPDK_17.11 {
>   	rte_power_freq_enable_turbo;
>   	rte_power_turbo_status;
>   
> -} DPDK_2.0;
> \ No newline at end of file
> +} DPDK_2.0;
> +
> +DPDK_18.08 {
> +	global:
> +
> +	rte_power_empty_poll_set_freq;
> +	rte_power_empty_poll_setup_timer;
> +	rte_power_empty_poll_stat_free;
> +	rte_power_empty_poll_stat_init;
> +	rte_power_empty_poll_stat_update;
> +	rte_power_poll_stat_update;
> +
> +} DPDK_17.11;

Acked-by: David Hunt<david.hunt at intel.com>