[EXT] [PATCH v2] eventdev/timer: add API to get remaining ticks

[Pavan Nikhilesh Bhagavatula]

> -----Original Message-----
> From: Erik Gabriel Carrillo <erik.g.carrillo at intel.com>
> Sent: Tuesday, December 20, 2022 1:29 AM
> To: Jerin Jacob Kollanukkaran <jerinj at marvell.com>
> Cc: hofors at lysator.liu.se; s.v.naga.harish.k at intel.com;
> jay.jayatheerthan at intel.com; Pavan Nikhilesh Bhagavatula
> <pbhagavatula at marvell.com>; Shijith Thotton <sthotton at marvell.com>;
> dev at dpdk.org
> Subject: [EXT] [PATCH v2] eventdev/timer: add API to get remaining ticks
> 
> External Email
> 
> ----------------------------------------------------------------------
> Introduce an event timer adapter API which allows users to determine how
> many adapter ticks remain until an event timer fires.
> 
> Signed-off-by: Erik Gabriel Carrillo <erik.g.carrillo at intel.com>
> ---
> v2:
> * Rename API to rte_event_timer_get_remaining_ticks
> * Assert that API out param is non-NULL instead of checking and returning
>   error
> 
>  app/test/test_event_timer_adapter.c    | 68
> ++++++++++++++++++++++++++
>  lib/eventdev/event_timer_adapter_pmd.h |  7 +++
>  lib/eventdev/rte_event_timer_adapter.c | 52 ++++++++++++++++++++
>  lib/eventdev/rte_event_timer_adapter.h | 27 ++++++++++
>  lib/eventdev/version.map               |  3 ++
>  5 files changed, 157 insertions(+)
> 
> diff --git a/app/test/test_event_timer_adapter.c
> b/app/test/test_event_timer_adapter.c
> index 1a440dfd10..1a1fb48b24 100644
> --- a/app/test/test_event_timer_adapter.c
> +++ b/app/test/test_event_timer_adapter.c
> @@ -1920,6 +1920,72 @@ adapter_create_max(void)
>  	return TEST_SUCCESS;
>  }
> 
> +static inline int
> +test_timer_ticks_remaining(void)
> +{
> +	uint64_t ticks_remaining = UINT64_MAX;
> +	struct rte_event_timer *ev_tim;
> +	struct rte_event ev;
> +	int ret, i;
> +	const struct rte_event_timer tim = {
> +		.ev.op = RTE_EVENT_OP_NEW,
> +		.ev.queue_id = 0,
> +		.ev.sched_type = RTE_SCHED_TYPE_ATOMIC,
> +		.ev.priority = RTE_EVENT_DEV_PRIORITY_NORMAL,
> +		.ev.event_type =  RTE_EVENT_TYPE_TIMER,
> +		.state = RTE_EVENT_TIMER_NOT_ARMED,
> +	};
> +
> +	rte_mempool_get(eventdev_test_mempool, (void **)&ev_tim);
> +	*ev_tim = tim;
> +	ev_tim->ev.event_ptr = ev_tim;
> +#define TEST_TICKS 5
> +	ev_tim->timeout_ticks = CALC_TICKS(TEST_TICKS);
> +
> +	/* Test that unarmed timer returns error */
> +	TEST_ASSERT_FAIL(rte_event_timer_get_remaining_ticks(timdev,
> ev_tim,
> +							     &ticks_remaining),
> +			 "Didn't fail to get ticks for unarmed event timer");

Please handle ENOSUP case.

> +
> +	TEST_ASSERT_EQUAL(rte_event_timer_arm_burst(timdev,
> &ev_tim, 1), 1,
> +			  "Failed to arm timer with proper timeout.");
> +	TEST_ASSERT_EQUAL(ev_tim->state, RTE_EVENT_TIMER_ARMED,
> +			  "Improper timer state set expected %d returned
> %d",
> +			  RTE_EVENT_TIMER_ARMED, ev_tim->state);
> +
> +	for (i = 0; i < TEST_TICKS; i++) {
> +		ret = rte_event_timer_get_remaining_ticks(timdev, ev_tim,
> +							  &ticks_remaining);
> +		if (ret < 0)
> +			return TEST_FAILED;
> +
> +		TEST_ASSERT_EQUAL((int)ticks_remaining, TEST_TICKS - i,
> +				  "Expected %d ticks remaining, got
> %"PRIu64"",
> +				  TEST_TICKS - i, ticks_remaining);
> +
> +		rte_delay_ms(100);
> +	}
> +
> +	rte_delay_ms(100);
> +
> +	TEST_ASSERT_EQUAL(rte_event_dequeue_burst(evdev, 0, &ev, 1,
> 0), 1,
> +			  "Armed timer failed to trigger.");
> +	TEST_ASSERT_EQUAL(ev_tim->state,
> RTE_EVENT_TIMER_NOT_ARMED,
> +			  "Improper timer state set expected %d returned
> %d",
> +			  RTE_EVENT_TIMER_NOT_ARMED, ev_tim->state);
> +
> +	/* Test that timer that fired returns error */
> +	TEST_ASSERT_FAIL(rte_event_timer_get_remaining_ticks(timdev,
> ev_tim,
> +							   &ticks_remaining),
> +			 "Didn't fail to get ticks for unarmed event timer");
> +
> +	rte_mempool_put(eventdev_test_mempool, (void *)ev_tim);
> +
> +#undef TEST_TICKS
> +	return TEST_SUCCESS;
> +}
> +
> +
>  static struct unit_test_suite event_timer_adptr_functional_testsuite  = {
>  	.suite_name = "event timer functional test suite",
>  	.setup = testsuite_setup,
> @@ -1982,6 +2048,8 @@ static struct unit_test_suite
> event_timer_adptr_functional_testsuite  = {
>  		TEST_CASE_ST(timdev_setup_msec, timdev_teardown,
>  				adapter_tick_resolution),
>  		TEST_CASE(adapter_create_max),
> +		TEST_CASE_ST(timdev_setup_msec, timdev_teardown,
> +				test_timer_ticks_remaining),
>  		TEST_CASES_END() /**< NULL terminate unit test array */
>  	}
>  };
> diff --git a/lib/eventdev/event_timer_adapter_pmd.h
> b/lib/eventdev/event_timer_adapter_pmd.h
> index 189017b5c1..7ba9df463b 100644
> --- a/lib/eventdev/event_timer_adapter_pmd.h
> +++ b/lib/eventdev/event_timer_adapter_pmd.h
> @@ -52,6 +52,11 @@ typedef int (*rte_event_timer_adapter_stats_get_t)(
>  typedef int (*rte_event_timer_adapter_stats_reset_t)(
>  		const struct rte_event_timer_adapter *adapter);
>  /**< @internal Reset statistics for event timer adapter */
> +typedef int (*rte_event_timer_get_remaining_ticks_t)(
> +		const struct rte_event_timer_adapter *adapter,
> +		const struct rte_event_timer *evtim,
> +		uint64_t *ticks_remaining);
> +/**< @internal Get remaining ticks for event timer */
> 
>  /**
>   * @internal Structure containing the functions exported by an event timer
> @@ -74,6 +79,8 @@ struct event_timer_adapter_ops {
>  	/**< Arm event timers with same expiration time */
>  	rte_event_timer_cancel_burst_t		cancel_burst;
>  	/**< Cancel one or more event timers */
> +	rte_event_timer_get_remaining_ticks_t	get_remaining_ticks;
> +	/**< Get remaining ticks for event timer */
>  };
> 
>  /**
> diff --git a/lib/eventdev/rte_event_timer_adapter.c
> b/lib/eventdev/rte_event_timer_adapter.c
> index a0f14bf861..ff762bb5f1 100644
> --- a/lib/eventdev/rte_event_timer_adapter.c
> +++ b/lib/eventdev/rte_event_timer_adapter.c
> @@ -8,6 +8,7 @@
>  #include <inttypes.h>
>  #include <stdbool.h>
>  #include <stdlib.h>
> +#include <math.h>
> 
>  #include <rte_memzone.h>
>  #include <rte_errno.h>
> @@ -458,6 +459,21 @@ rte_event_timer_adapter_stats_reset(struct
> rte_event_timer_adapter *adapter)
>  	return adapter->ops->stats_reset(adapter);
>  }
> 
> +int
> +rte_event_timer_get_remaining_ticks(
> +			const struct rte_event_timer_adapter *adapter,
> +			const struct rte_event_timer *evtim,
> +			uint64_t *ticks_remaining)
> +{
> +	ADAPTER_VALID_OR_ERR_RET(adapter, -EINVAL);
> +	FUNC_PTR_OR_ERR_RET(adapter->ops->get_remaining_ticks, -
> ENOTSUP);
> +
> +	RTE_ASSERT(ticks_remaining != NULL);
> +
> +	return adapter->ops->get_remaining_ticks(adapter, evtim,
> +						 ticks_remaining);
> +}
> +
>  /*
>   * Software event timer adapter buffer helper functions
>   */
> @@ -1072,6 +1088,41 @@ swtim_stats_reset(const struct
> rte_event_timer_adapter *adapter)
>  	return 0;
>  }
> 
> +static int
> +swtim_get_remaining_ticks(const struct rte_event_timer_adapter
> *adapter,
> +			  const struct rte_event_timer *evtim,
> +			  uint64_t *ticks_remaining)
> +{
> +	uint64_t nsecs_per_adapter_tick, opaque, cycles_remaining;
> +	enum rte_event_timer_state n_state;
> +	double nsecs_per_cycle;
> +	struct rte_timer *tim;
> +	uint64_t cur_cycles;
> +
> +	/* Check that timer is armed */
> +	n_state = __atomic_load_n(&evtim->state, __ATOMIC_ACQUIRE);
> +	if (n_state != RTE_EVENT_TIMER_ARMED)
> +		return -EINVAL;
> +
> +	opaque = evtim->impl_opaque[0];
> +	tim = (struct rte_timer *)(uintptr_t)opaque;
> +
> +	cur_cycles = rte_get_timer_cycles();
> +	if (cur_cycles > tim->expire) {
> +		*ticks_remaining = 0;
> +		return 0;
> +	}
> +
> +	cycles_remaining = tim->expire - cur_cycles;
> +	nsecs_per_cycle = (double)NSECPERSEC / rte_get_timer_hz();
> +	nsecs_per_adapter_tick = adapter->data->conf.timer_tick_ns;
> +
> +	*ticks_remaining = (uint64_t)ceil((cycles_remaining *
> nsecs_per_cycle) /
> +					  nsecs_per_adapter_tick);
> +
> +	return 0;
> +}
> +
>  static uint16_t
>  __swtim_arm_burst(const struct rte_event_timer_adapter *adapter,
>  		struct rte_event_timer **evtims,
> @@ -1286,6 +1337,7 @@ static const struct event_timer_adapter_ops
> swtim_ops = {
>  	.arm_burst = swtim_arm_burst,
>  	.arm_tmo_tick_burst = swtim_arm_tmo_tick_burst,
>  	.cancel_burst = swtim_cancel_burst,
> +	.get_remaining_ticks = swtim_get_remaining_ticks,
>  };
> 
>  static int
> diff --git a/lib/eventdev/rte_event_timer_adapter.h
> b/lib/eventdev/rte_event_timer_adapter.h
> index cd10db19e4..1e43c09612 100644
> --- a/lib/eventdev/rte_event_timer_adapter.h
> +++ b/lib/eventdev/rte_event_timer_adapter.h
> @@ -678,6 +678,33 @@ rte_event_timer_cancel_burst(const struct
> rte_event_timer_adapter *adapter,
>  	return adapter->cancel_burst(adapter, evtims, nb_evtims);
>  }
> 
> +/**
> + * @warning
> + * @b EXPERIMENTAL: this API may change without prior notice
> + *
> + * Get the number of ticks remaining until an event timer fires.
> + *
> + * @param adapter
> + *   A pointer to an event timer adapter structure
> + * @param evtim
> + *   A pointer to an rte_event_timer structure
> + * @param[out] ticks_remaining
> + *   Pointer to variable into which to write the number of ticks remaining
> + *   until the event timer fires
> + *
> + * @return
> + *   - 0: Success
> + *   - -EINVAL Invalid timer adapter identifier or the event timer is not in
> + *   the armed state
> + *   - -ENOTSUP The timer adapter implementation does not support this
> API.
> + */
> +__rte_experimental
> +int
> +rte_event_timer_get_remaining_ticks(
> +			const struct rte_event_timer_adapter *adapter,
> +			const struct rte_event_timer *evtim,
> +			uint64_t *ticks_remaining);
> +
>  #ifdef __cplusplus
>  }
>  #endif
> diff --git a/lib/eventdev/version.map b/lib/eventdev/version.map
> index dd63ec6f68..2b702b6b15 100644
> --- a/lib/eventdev/version.map
> +++ b/lib/eventdev/version.map
> @@ -118,6 +118,9 @@ EXPERIMENTAL {
>  	rte_event_eth_tx_adapter_instance_get;
>  	rte_event_eth_tx_adapter_queue_start;
>  	rte_event_eth_tx_adapter_queue_stop;
> +
> +	# added in 23.03
> +	rte_event_timer_get_remaining_ticks;
>  };
> 
>  INTERNAL {
> --
> 2.23.0