Commit 42ad32da authored by Shuhei Matsumoto's avatar Shuhei Matsumoto Committed by Tomasz Zawadzki
Browse files

thread: Change if-else_if to switch-case blocks of spdk_poller_pause/resume() 



It will be sufficiently reasonable to check if the caller thread is valid
even if spdk_poller_pause() or spdk_poller_resume() does nothing.
Besides, let's write all possibles states explicitly in switch - cases.

This refactoring clarifies the logic and makes the following patches easier.

Signed-off-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Change-Id: I1163eff388fe741d6b6924f474a82b1aa7d18acb
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/7665


Community-CI: Mellanox Build Bot
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
Reviewed-by: default avatarKonrad Sztyber <konrad.sztyber@intel.com>
Reviewed-by: default avatarAleksey Marchuk <alexeymar@mellanox.com>
Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
parent 3f45ed24

lib/thread/thread.c

+24 −16
Original line number Diff line number Diff line
@@ -1391,11 +1391,6 @@ spdk_poller_pause(struct spdk_poller *poller) 
{

	struct spdk_thread *thread;



	if (poller->state == SPDK_POLLER_STATE_PAUSED ||

	    poller->state == SPDK_POLLER_STATE_PAUSING) {

		return;

	}



	thread = spdk_get_thread();

	if (!thread) {

		assert(false);
@@ -1414,9 +1409,11 @@ spdk_poller_pause(struct spdk_poller *poller) 
	 * allows a poller to be paused from another one's context without

	 * breaking the TAILQ_FOREACH_REVERSE_SAFE iteration.

	 */

	if (poller->state != SPDK_POLLER_STATE_RUNNING) {

		poller->state = SPDK_POLLER_STATE_PAUSING;

	} else {

	switch (poller->state) {

	case SPDK_POLLER_STATE_PAUSED:

	case SPDK_POLLER_STATE_PAUSING:

		break;

	case SPDK_POLLER_STATE_RUNNING:

		if (poller->period_ticks > 0) {

			TAILQ_REMOVE(&thread->timed_pollers, poller, tailq);

		} else {
@@ -1425,6 +1422,13 @@ spdk_poller_pause(struct spdk_poller *poller) 


		TAILQ_INSERT_TAIL(&thread->paused_pollers, poller, tailq);

		poller->state = SPDK_POLLER_STATE_PAUSED;

		break;

	case SPDK_POLLER_STATE_WAITING:

		poller->state = SPDK_POLLER_STATE_PAUSING;

		break;

	default:

		assert(false);

		break;

	}

}
@@ -1433,11 +1437,6 @@ spdk_poller_resume(struct spdk_poller *poller) 
{

	struct spdk_thread *thread;



	if (poller->state != SPDK_POLLER_STATE_PAUSED &&

	    poller->state != SPDK_POLLER_STATE_PAUSING) {

		return;

	}



	thread = spdk_get_thread();

	if (!thread) {

		assert(false);
@@ -1456,12 +1455,21 @@ spdk_poller_resume(struct spdk_poller *poller) 
	 * we just need to flip its state back to waiting, as it's already on

	 * the appropriate list.

	 */

	if (poller->state == SPDK_POLLER_STATE_PAUSED) {

	switch (poller->state) {

	case SPDK_POLLER_STATE_PAUSED:

		TAILQ_REMOVE(&thread->paused_pollers, poller, tailq);

		thread_insert_poller(thread, poller);

	}



	/* fallthrough */

	case SPDK_POLLER_STATE_PAUSING:

		poller->state = SPDK_POLLER_STATE_WAITING;

		break;

	case SPDK_POLLER_STATE_RUNNING:

	case SPDK_POLLER_STATE_WAITING:

		break;

	default:

		assert(false);

		break;

	}

}



const char *