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From: Shijith Thotton <sthotton@marvell.com>
To: <erik.g.carrillo@intel.com>, <jerinj@marvell.com>
Cc: Shijith Thotton <sthotton@marvell.com>, <dev@dpdk.org>,
	<pbhagavatula@marvell.com>, <stable@dpdk.org>
Subject: [PATCH v2] eventdev/timer: fix timeout event wait behavior
Date: Tue, 21 Mar 2023 10:50:23 +0530	[thread overview]
Message-ID: <90fb5b328eda4c7f83cfb11998ba32a01935ff8e.1679375813.git.sthotton@marvell.com> (raw)
In-Reply-To: <d7f77765b09c5333df105c317344e983a2f1ad45.1678867113.git.sthotton@marvell.com>

Improved the accuracy and consistency of timeout event wait behavior by
refactoring it. Previously, the delay function used for waiting could be
inaccurate, leading to inconsistent results. This commit updates the
wait behavior to use a timeout-based approach, enabling the wait for the
exact number of timer ticks before proceeding.

The new function timeout_event_dequeue mimics the behavior of the tested
systems closely. It dequeues timer expiry events until either the
expected number of events have been dequeued or the specified time has
elapsed. The WAIT_TICKS macro defines the waiting behavior based on the
type of timer being used (software or hardware).

Fixes: d1f3385d0076 ("test: add event timer adapter auto-test")

Signed-off-by: Shijith Thotton <sthotton@marvell.com>
---
v2:
- Updated commit message and added fixed tag.

 app/test/test_event_timer_adapter.c | 169 +++++++++++-----------------
 1 file changed, 68 insertions(+), 101 deletions(-)

diff --git a/app/test/test_event_timer_adapter.c b/app/test/test_event_timer_adapter.c
index 5e7feec1c7..510bebcf86 100644
--- a/app/test/test_event_timer_adapter.c
+++ b/app/test/test_event_timer_adapter.c
@@ -57,9 +57,10 @@ static uint64_t global_bkt_tck_ns;
 static uint64_t global_info_bkt_tck_ns;
 static volatile uint8_t arm_done;
 
-#define CALC_TICKS(tks)					\
-	ceil((double)(tks * global_bkt_tck_ns) / global_info_bkt_tck_ns)
+#define CALC_TICKS(tks) ceil((double)((tks) * global_bkt_tck_ns) / global_info_bkt_tck_ns)
 
+/* Wait double timeout ticks for software and an extra tick for hardware */
+#define WAIT_TICKS(tks) (using_services ? 2 * (tks) : tks + 1)
 
 static bool using_services;
 static uint32_t test_lcore1;
@@ -441,10 +442,31 @@ timdev_teardown(void)
 	rte_mempool_free(eventdev_test_mempool);
 }
 
+static inline uint16_t
+timeout_event_dequeue(struct rte_event *evs, uint64_t nb_evs, uint64_t ticks)
+{
+	uint16_t ev_cnt = 0;
+	uint64_t end_cycle;
+
+	if (using_services && nb_evs == MAX_TIMERS)
+		ticks = 2 * ticks;
+
+	end_cycle = rte_rdtsc() + ticks * global_bkt_tck_ns * rte_get_tsc_hz() / 1E9;
+
+	while (ev_cnt < nb_evs && rte_rdtsc() < end_cycle) {
+		ev_cnt += rte_event_dequeue_burst(evdev, TEST_PORT_ID, &evs[ev_cnt], nb_evs, 0);
+		rte_pause();
+	}
+
+	return ev_cnt;
+}
+
 static inline int
 test_timer_state(void)
 {
 	struct rte_event_timer *ev_tim;
+	const uint64_t max_ticks = 100;
+	uint64_t ticks, wait_ticks;
 	struct rte_event ev;
 	const struct rte_event_timer tim = {
 		.ev.op = RTE_EVENT_OP_NEW,
@@ -455,11 +477,10 @@ test_timer_state(void)
 		.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;
-	ev_tim->timeout_ticks = CALC_TICKS(120);
+	ev_tim->timeout_ticks = CALC_TICKS(max_ticks + 20);
 
 	TEST_ASSERT_EQUAL(rte_event_timer_arm_burst(timdev, &ev_tim, 1), 0,
 			"Armed timer exceeding max_timeout.");
@@ -467,8 +488,9 @@ test_timer_state(void)
 			"Improper timer state set expected %d returned %d",
 			RTE_EVENT_TIMER_ERROR_TOOLATE, ev_tim->state);
 
+	ticks = 10;
 	ev_tim->state = RTE_EVENT_TIMER_NOT_ARMED;
-	ev_tim->timeout_ticks = CALC_TICKS(10);
+	ev_tim->timeout_ticks = CALC_TICKS(ticks);
 
 	TEST_ASSERT_EQUAL(rte_event_timer_arm_burst(timdev, &ev_tim, 1), 1,
 			"Failed to arm timer with proper timeout.");
@@ -477,14 +499,15 @@ test_timer_state(void)
 			RTE_EVENT_TIMER_ARMED, ev_tim->state);
 
 	if (!using_services)
-		rte_delay_us(20);
+		wait_ticks = 2 * ticks;
 	else
-		rte_delay_us(1000 + 200);
-	TEST_ASSERT_EQUAL(rte_event_dequeue_burst(evdev, 0, &ev, 1, 0), 1,
-			"Armed timer failed to trigger.");
+		wait_ticks = ticks;
+
+	TEST_ASSERT_EQUAL(timeout_event_dequeue(&ev, 1, WAIT_TICKS(wait_ticks)), 1,
+			  "Armed timer failed to trigger.");
 
 	ev_tim->state = RTE_EVENT_TIMER_NOT_ARMED;
-	ev_tim->timeout_ticks = CALC_TICKS(90);
+	ev_tim->timeout_ticks = CALC_TICKS(max_ticks - 10);
 	TEST_ASSERT_EQUAL(rte_event_timer_arm_burst(timdev, &ev_tim, 1), 1,
 			"Failed to arm timer with proper timeout.");
 	TEST_ASSERT_EQUAL(rte_event_timer_cancel_burst(timdev, &ev_tim, 1),
@@ -1208,8 +1231,9 @@ stat_inc_reset_ev_enq(void)
 	int ret, i, n;
 	int num_evtims = MAX_TIMERS;
 	struct rte_event_timer *evtims[num_evtims];
-	struct rte_event evs[BATCH_SIZE];
+	struct rte_event evs[num_evtims];
 	struct rte_event_timer_adapter_stats stats;
+	uint64_t ticks = 5;
 	const struct rte_event_timer init_tim = {
 		.ev.op = RTE_EVENT_OP_NEW,
 		.ev.queue_id = TEST_QUEUE_ID,
@@ -1217,7 +1241,7 @@ stat_inc_reset_ev_enq(void)
 		.ev.priority = RTE_EVENT_DEV_PRIORITY_NORMAL,
 		.ev.event_type =  RTE_EVENT_TYPE_TIMER,
 		.state = RTE_EVENT_TIMER_NOT_ARMED,
-		.timeout_ticks = CALC_TICKS(5), // expire in .5 sec
+		.timeout_ticks = CALC_TICKS(ticks), /**< expire in .5 sec */
 	};
 
 	ret = rte_mempool_get_bulk(eventdev_test_mempool, (void **)evtims,
@@ -1242,31 +1266,12 @@ stat_inc_reset_ev_enq(void)
 			  "succeeded = %d, rte_errno = %s",
 			  num_evtims, ret, rte_strerror(rte_errno));
 
-	rte_delay_ms(1000);
-
-#define MAX_TRIES num_evtims
-	int sum = 0;
-	int tries = 0;
-	bool done = false;
-	while (!done) {
-		sum += rte_event_dequeue_burst(evdev, TEST_PORT_ID, evs,
-					       RTE_DIM(evs), 10);
-		if (sum >= num_evtims || ++tries >= MAX_TRIES)
-			done = true;
-
-		rte_delay_ms(10);
-	}
-
-	TEST_ASSERT_EQUAL(sum, num_evtims, "Expected %d timer expiry events, "
-			  "got %d", num_evtims, sum);
-
-	TEST_ASSERT(tries < MAX_TRIES, "Exceeded max tries");
-
-	rte_delay_ms(100);
+	n = timeout_event_dequeue(evs, RTE_DIM(evs), WAIT_TICKS(ticks));
+	TEST_ASSERT_EQUAL(n, num_evtims, "Expected %d timer expiry events, got %d",
+			  num_evtims, n);
 
 	/* Make sure the eventdev is still empty */
-	n = rte_event_dequeue_burst(evdev, TEST_PORT_ID, evs, RTE_DIM(evs),
-				      10);
+	n = timeout_event_dequeue(evs, 1, WAIT_TICKS(1));
 
 	TEST_ASSERT_EQUAL(n, 0, "Dequeued unexpected number of timer expiry "
 			  "events from event device");
@@ -1303,6 +1308,7 @@ event_timer_arm(void)
 	struct rte_event_timer_adapter *adapter = timdev;
 	struct rte_event_timer *evtim = NULL;
 	struct rte_event evs[BATCH_SIZE];
+	uint64_t ticks = 5;
 	const struct rte_event_timer init_tim = {
 		.ev.op = RTE_EVENT_OP_NEW,
 		.ev.queue_id = TEST_QUEUE_ID,
@@ -1310,7 +1316,7 @@ event_timer_arm(void)
 		.ev.priority = RTE_EVENT_DEV_PRIORITY_NORMAL,
 		.ev.event_type =  RTE_EVENT_TYPE_TIMER,
 		.state = RTE_EVENT_TIMER_NOT_ARMED,
-		.timeout_ticks = CALC_TICKS(5), // expire in .5 sec
+		.timeout_ticks = CALC_TICKS(ticks), /**< expire in .5 sec */
 	};
 
 	rte_mempool_get(eventdev_test_mempool, (void **)&evtim);
@@ -1337,10 +1343,7 @@ event_timer_arm(void)
 	TEST_ASSERT_EQUAL(rte_errno, EALREADY, "Unexpected rte_errno value "
 			  "after arming already armed timer");
 
-	/* Let timer expire */
-	rte_delay_ms(1000);
-
-	n = rte_event_dequeue_burst(evdev, TEST_PORT_ID, evs, RTE_DIM(evs), 0);
+	n = timeout_event_dequeue(evs, RTE_DIM(evs), WAIT_TICKS(ticks));
 	TEST_ASSERT_EQUAL(n, 1, "Failed to dequeue expected number of expiry "
 			  "events from event device");
 
@@ -1360,6 +1363,7 @@ event_timer_arm_double(void)
 	struct rte_event_timer_adapter *adapter = timdev;
 	struct rte_event_timer *evtim = NULL;
 	struct rte_event evs[BATCH_SIZE];
+	uint64_t ticks = 5;
 	const struct rte_event_timer init_tim = {
 		.ev.op = RTE_EVENT_OP_NEW,
 		.ev.queue_id = TEST_QUEUE_ID,
@@ -1367,7 +1371,7 @@ event_timer_arm_double(void)
 		.ev.priority = RTE_EVENT_DEV_PRIORITY_NORMAL,
 		.ev.event_type =  RTE_EVENT_TYPE_TIMER,
 		.state = RTE_EVENT_TIMER_NOT_ARMED,
-		.timeout_ticks = CALC_TICKS(5), // expire in .5 sec
+		.timeout_ticks = CALC_TICKS(ticks), /**< expire in .5 sec */
 	};
 
 	rte_mempool_get(eventdev_test_mempool, (void **)&evtim);
@@ -1387,10 +1391,7 @@ event_timer_arm_double(void)
 	TEST_ASSERT_EQUAL(rte_errno, EALREADY, "Unexpected rte_errno value "
 			  "after double-arm");
 
-	/* Let timer expire */
-	rte_delay_ms(600);
-
-	n = rte_event_dequeue_burst(evdev, TEST_PORT_ID, evs, RTE_DIM(evs), 0);
+	n = timeout_event_dequeue(evs, RTE_DIM(evs), WAIT_TICKS(ticks));
 	TEST_ASSERT_EQUAL(n, 1, "Dequeued incorrect number of expiry events - "
 			  "expected: 1, actual: %d", n);
 
@@ -1417,6 +1418,7 @@ event_timer_arm_expiry(void)
 		.ev.event_type =  RTE_EVENT_TYPE_TIMER,
 		.state = RTE_EVENT_TIMER_NOT_ARMED,
 	};
+	uint64_t ticks = 30;
 
 	rte_mempool_get(eventdev_test_mempool, (void **)&evtim);
 	if (evtim == NULL) {
@@ -1426,7 +1428,7 @@ event_timer_arm_expiry(void)
 
 	/* Set up an event timer */
 	*evtim = init_tim;
-	evtim->timeout_ticks = CALC_TICKS(30),	// expire in 3 secs
+	evtim->timeout_ticks = CALC_TICKS(ticks); /**< expire in 3 secs */
 	evtim->ev.event_ptr = evtim;
 
 	ret = rte_event_timer_arm_burst(adapter, &evtim, 1);
@@ -1435,17 +1437,10 @@ event_timer_arm_expiry(void)
 	TEST_ASSERT_EQUAL(evtim->state, RTE_EVENT_TIMER_ARMED, "Event "
 			  "timer in incorrect state");
 
-	rte_delay_ms(2999);
-
-	n = rte_event_dequeue_burst(evdev, TEST_PORT_ID, evs, RTE_DIM(evs), 0);
+	n = timeout_event_dequeue(evs, RTE_DIM(evs), ticks - 1);
 	TEST_ASSERT_EQUAL(n, 0, "Dequeued unexpected timer expiry event");
 
-	/* Delay 100 ms to account for the adapter tick window - should let us
-	 * dequeue one event
-	 */
-	rte_delay_ms(100);
-
-	n = rte_event_dequeue_burst(evdev, TEST_PORT_ID, evs, RTE_DIM(evs), 0);
+	n = timeout_event_dequeue(evs, RTE_DIM(evs), WAIT_TICKS(1));
 	TEST_ASSERT_EQUAL(n, 1, "Dequeued incorrect number (%d) of timer "
 			  "expiry events", n);
 	TEST_ASSERT_EQUAL(evs[0].event_type, RTE_EVENT_TYPE_TIMER,
@@ -1477,6 +1472,7 @@ event_timer_arm_rearm(void)
 		.ev.event_type = RTE_EVENT_TYPE_TIMER,
 		.state = RTE_EVENT_TIMER_NOT_ARMED,
 	};
+	uint64_t ticks = 1;
 
 	rte_mempool_get(eventdev_test_mempool, (void **)&evtim);
 	if (evtim == NULL) {
@@ -1486,7 +1482,7 @@ event_timer_arm_rearm(void)
 
 	/* Set up a timer */
 	*evtim = init_tim;
-	evtim->timeout_ticks = CALC_TICKS(1);  // expire in 0.1 sec
+	evtim->timeout_ticks = CALC_TICKS(ticks); /**< expire in 0.1 sec */
 	evtim->ev.event_ptr = evtim;
 
 	/* Arm it */
@@ -1494,10 +1490,7 @@ event_timer_arm_rearm(void)
 	TEST_ASSERT_EQUAL(ret, 1, "Failed to arm event timer: %s\n",
 			  rte_strerror(rte_errno));
 
-	/* Add 100ms to account for the adapter tick window */
-	rte_delay_ms(100 + 100);
-
-	n = rte_event_dequeue_burst(evdev, TEST_PORT_ID, evs, RTE_DIM(evs), 0);
+	n = timeout_event_dequeue(evs, RTE_DIM(evs), WAIT_TICKS(ticks));
 	TEST_ASSERT_EQUAL(n, 1, "Failed to dequeue expected number of expiry "
 			  "events from event device");
 
@@ -1514,10 +1507,7 @@ event_timer_arm_rearm(void)
 	TEST_ASSERT_EQUAL(ret, 1, "Failed to arm event timer: %s\n",
 			  rte_strerror(rte_errno));
 
-	/* Add 100ms to account for the adapter tick window */
-	rte_delay_ms(100 + 100);
-
-	n = rte_event_dequeue_burst(evdev, TEST_PORT_ID, evs, RTE_DIM(evs), 0);
+	n = timeout_event_dequeue(evs, RTE_DIM(evs), WAIT_TICKS(ticks));
 	TEST_ASSERT_EQUAL(n, 1, "Failed to dequeue expected number of expiry "
 			  "events from event device");
 
@@ -1539,7 +1529,8 @@ event_timer_arm_max(void)
 	int ret, i, n;
 	int num_evtims = MAX_TIMERS;
 	struct rte_event_timer *evtims[num_evtims];
-	struct rte_event evs[BATCH_SIZE];
+	struct rte_event evs[num_evtims];
+	uint64_t ticks = 5;
 	const struct rte_event_timer init_tim = {
 		.ev.op = RTE_EVENT_OP_NEW,
 		.ev.queue_id = TEST_QUEUE_ID,
@@ -1547,7 +1538,7 @@ event_timer_arm_max(void)
 		.ev.priority = RTE_EVENT_DEV_PRIORITY_NORMAL,
 		.ev.event_type =  RTE_EVENT_TYPE_TIMER,
 		.state = RTE_EVENT_TIMER_NOT_ARMED,
-		.timeout_ticks = CALC_TICKS(5), // expire in .5 sec
+		.timeout_ticks = CALC_TICKS(ticks), /**< expire in .5 sec */
 	};
 
 	ret = rte_mempool_get_bulk(eventdev_test_mempool, (void **)evtims,
@@ -1567,31 +1558,12 @@ event_timer_arm_max(void)
 			  "succeeded = %d, rte_errno = %s",
 			  num_evtims, ret, rte_strerror(rte_errno));
 
-	rte_delay_ms(1000);
-
-#define MAX_TRIES num_evtims
-	int sum = 0;
-	int tries = 0;
-	bool done = false;
-	while (!done) {
-		sum += rte_event_dequeue_burst(evdev, TEST_PORT_ID, evs,
-					       RTE_DIM(evs), 10);
-		if (sum >= num_evtims || ++tries >= MAX_TRIES)
-			done = true;
-
-		rte_delay_ms(10);
-	}
-
-	TEST_ASSERT_EQUAL(sum, num_evtims, "Expected %d timer expiry events, "
-			  "got %d", num_evtims, sum);
-
-	TEST_ASSERT(tries < MAX_TRIES, "Exceeded max tries");
-
-	rte_delay_ms(100);
+	n = timeout_event_dequeue(evs, RTE_DIM(evs), WAIT_TICKS(ticks));
+	TEST_ASSERT_EQUAL(n, num_evtims, "Expected %d timer expiry events, got %d",
+			  num_evtims, n);
 
 	/* Make sure the eventdev is still empty */
-	n = rte_event_dequeue_burst(evdev, TEST_PORT_ID, evs, RTE_DIM(evs),
-				    10);
+	n = timeout_event_dequeue(evs, 1, WAIT_TICKS(1));
 
 	TEST_ASSERT_EQUAL(n, 0, "Dequeued unexpected number of timer expiry "
 			  "events from event device");
@@ -1711,6 +1683,7 @@ event_timer_cancel(void)
 		.ev.event_type =  RTE_EVENT_TYPE_TIMER,
 		.state = RTE_EVENT_TIMER_NOT_ARMED,
 	};
+	uint64_t ticks = 30;
 
 	rte_mempool_get(eventdev_test_mempool, (void **)&evtim);
 	if (evtim == NULL) {
@@ -1728,7 +1701,7 @@ event_timer_cancel(void)
 	/* Set up a timer */
 	*evtim = init_tim;
 	evtim->ev.event_ptr = evtim;
-	evtim->timeout_ticks = CALC_TICKS(30);  // expire in 3 sec
+	evtim->timeout_ticks = CALC_TICKS(ticks); /**< expire in 3 sec */
 
 	/* Check that cancelling an inited but unarmed timer fails */
 	ret = rte_event_timer_cancel_burst(adapter, &evtim, 1);
@@ -1752,10 +1725,8 @@ event_timer_cancel(void)
 	TEST_ASSERT_EQUAL(evtim->state, RTE_EVENT_TIMER_CANCELED,
 			  "evtim in incorrect state");
 
-	rte_delay_ms(3000);
-
 	/* Make sure that no expiry event was generated */
-	n = rte_event_dequeue_burst(evdev, TEST_PORT_ID, evs, RTE_DIM(evs), 0);
+	n = timeout_event_dequeue(evs, RTE_DIM(evs), WAIT_TICKS(ticks));
 	TEST_ASSERT_EQUAL(n, 0, "Dequeued unexpected timer expiry event\n");
 
 	rte_mempool_put(eventdev_test_mempool, evtim);
@@ -1778,8 +1749,8 @@ event_timer_cancel_double(void)
 		.ev.priority = RTE_EVENT_DEV_PRIORITY_NORMAL,
 		.ev.event_type =  RTE_EVENT_TYPE_TIMER,
 		.state = RTE_EVENT_TIMER_NOT_ARMED,
-		.timeout_ticks = CALC_TICKS(5), // expire in .5 sec
 	};
+	uint64_t ticks = 30;
 
 	rte_mempool_get(eventdev_test_mempool, (void **)&evtim);
 	if (evtim == NULL) {
@@ -1790,7 +1761,7 @@ event_timer_cancel_double(void)
 	/* Set up a timer */
 	*evtim = init_tim;
 	evtim->ev.event_ptr = evtim;
-	evtim->timeout_ticks = CALC_TICKS(30);  // expire in 3 sec
+	evtim->timeout_ticks = CALC_TICKS(ticks); /**< expire in 3 sec */
 
 	ret = rte_event_timer_arm_burst(adapter, &evtim, 1);
 	TEST_ASSERT_EQUAL(ret, 1, "Failed to arm event timer: %s\n",
@@ -1812,10 +1783,8 @@ event_timer_cancel_double(void)
 	TEST_ASSERT_EQUAL(rte_errno, EALREADY, "Unexpected rte_errno value "
 			  "after double-cancel: rte_errno = %d", rte_errno);
 
-	rte_delay_ms(3000);
-
 	/* Still make sure that no expiry event was generated */
-	n = rte_event_dequeue_burst(evdev, TEST_PORT_ID, evs, RTE_DIM(evs), 0);
+	n = timeout_event_dequeue(evs, RTE_DIM(evs), WAIT_TICKS(ticks));
 	TEST_ASSERT_EQUAL(n, 0, "Dequeued unexpected timer expiry event\n");
 
 	rte_mempool_put(eventdev_test_mempool, evtim);
@@ -1973,9 +1942,7 @@ test_timer_ticks_remaining(void)
 		rte_delay_ms(100);
 	}
 
-	rte_delay_ms(100);
-
-	TEST_ASSERT_EQUAL(rte_event_dequeue_burst(evdev, 0, &ev, 1, 0), 1,
+	TEST_ASSERT_EQUAL(timeout_event_dequeue(&ev, 1, WAIT_TICKS(1)), 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",
-- 
2.25.1


  parent reply	other threads:[~2023-03-21  5:21 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-15  8:00 [PATCH v1] eventdev/timer: use loop to check for timeout events Shijith Thotton
2023-03-20 16:54 ` Jerin Jacob
2023-03-21  5:20 ` Shijith Thotton [this message]
2023-04-04 10:52   ` [PATCH v2] eventdev/timer: fix timeout event wait behavior Jerin Jacob
2023-04-12 20:00   ` Carrillo, Erik G
2023-04-21  5:50     ` Jerin Jacob

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