Commit 885a86a5 authored by Ben Walker's avatar Ben Walker Committed by Daniel Verkamp
Browse files

event: Modify reactor to avoid calling spdk_get_ticks() 



Minimize the number of times spdk_get_ticks() is called
because it is expensive.

Change-Id: I2f34ca724ec28f42866b76d224dacbe1f31e7a41
Signed-off-by: default avatarBen Walker <benjamin.walker@intel.com>
parent 91d7d20c

lib/event/reactor.c

+17 −7
Original line number Diff line number Diff line
@@ -298,7 +298,7 @@ _spdk_reactor_run(void *arg) 
	struct spdk_reactor	*reactor = arg;

	struct spdk_poller	*poller;

	uint32_t		event_count;

	uint64_t		last_action, now;

	uint64_t		idle_started, now;

	uint64_t		spin_cycles, sleep_cycles;

	uint32_t		sleep_us;
@@ -309,12 +309,14 @@ _spdk_reactor_run(void *arg) 


	spin_cycles = SPDK_REACTOR_SPIN_TIME_US * spdk_get_ticks_hz() / 1000000ULL;

	sleep_cycles = reactor->max_delay_us * spdk_get_ticks_hz() / 1000000ULL;

	last_action = spdk_get_ticks();

	idle_started = 0;



	while (1) {

		bool took_action = false;



		event_count = spdk_event_queue_run_batch(rte_lcore_id());

		if (event_count > 0) {

			last_action = spdk_get_ticks();

			took_action = true;

		}



		poller = TAILQ_FIRST(&reactor->active_pollers);
@@ -328,7 +330,7 @@ _spdk_reactor_run(void *arg) 
				poller->state = SPDK_POLLER_STATE_WAITING;

				TAILQ_INSERT_TAIL(&reactor->active_pollers, poller, tailq);

			}

			last_action = spdk_get_ticks();

			took_action = true;

		}



		poller = TAILQ_FIRST(&reactor->timer_pollers);
@@ -345,14 +347,22 @@ _spdk_reactor_run(void *arg) 
					poller->state = SPDK_POLLER_STATE_WAITING;

					spdk_poller_insert_timer(reactor, poller, now);

				}

				last_action = spdk_get_ticks();

				took_action = true;

			}

		}



		if (took_action) {

			/* We were busy this loop iteration. Reset the idle timer. */

			idle_started = 0;

		} else if (idle_started == 0) {

			/* We were previously busy, but this loop we took no actions. */

			idle_started = spdk_get_ticks();

		}



		/* Determine if the thread can sleep */

		if (sleep_cycles > 0) {

		if (sleep_cycles && idle_started) {

			now = spdk_get_ticks();

			if (now >= (last_action + spin_cycles)) {

			if (now >= (idle_started + spin_cycles)) {

				sleep_us = reactor->max_delay_us;



				poller = TAILQ_FIRST(&reactor->timer_pollers);