Commit feb2c6be authored by Konrad Sztyber's avatar Konrad Sztyber Committed by Darek Stojaczyk
Browse files

lib/ftl: keep resubmitted writes on a queue 



Replaced single IO pointer with a queue. This allows multiple requests
to be queued when the writes cannot be scheduled.

Change-Id: I0cde50e7378108a6aab4ef6fe601cb854244f5d5
Signed-off-by: default avatarKonrad Sztyber <konrad.sztyber@intel.com>
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/455524


Reviewed-by: default avatarWojciech Malikowski <wojciech.malikowski@intel.com>
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
Reviewed-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: default avatarDarek Stojaczyk <dariusz.stojaczyk@intel.com>
Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
parent 8e6a5601

lib/ftl/ftl_core.c

+10 −8
Original line number Diff line number Diff line
@@ -67,8 +67,8 @@ struct ftl_wptr { 
	/* Current erase block */

	struct ftl_chunk		*chunk;



	/* IO that is currently processed */

	struct ftl_io			*current_io;

	/* Pending IO queue */

	TAILQ_HEAD(, ftl_io)		pending_queue;



	/* List link */

	LIST_ENTRY(ftl_wptr)		list_entry;
@@ -405,6 +405,7 @@ ftl_wptr_init(struct ftl_band *band) 
	wptr->band = band;

	wptr->chunk = CIRCLEQ_FIRST(&band->chunks);

	wptr->ppa = wptr->chunk->start_ppa;

	TAILQ_INIT(&wptr->pending_queue);



	return wptr;

}
@@ -1243,15 +1244,14 @@ ftl_submit_write(struct ftl_wptr *wptr, struct ftl_io *io) 
		/* There are no guarantees of the order of completion of NVMe IO submission queue */

		/* so wait until chunk is not busy before submitting another write */

		if (wptr->chunk->busy) {

			wptr->current_io = io;

			TAILQ_INSERT_TAIL(&wptr->pending_queue, io, retry_entry);

			rc = -EAGAIN;

			break;

		}



		rc = ftl_submit_child_write(wptr, io, dev->xfer_size);



		if (rc == -EAGAIN) {

			wptr->current_io = io;

			TAILQ_INSERT_TAIL(&wptr->pending_queue, io, retry_entry);

			break;

		} else if (rc) {

			ftl_io_fail(io, rc);
@@ -1301,11 +1301,13 @@ ftl_wptr_process_writes(struct ftl_wptr *wptr) 
	struct ftl_io		*io;

	struct ftl_ppa		ppa, prev_ppa;



	if (wptr->current_io) {

		if (ftl_submit_write(wptr, wptr->current_io) == -EAGAIN) {

	if (spdk_unlikely(!TAILQ_EMPTY(&wptr->pending_queue))) {

		io = TAILQ_FIRST(&wptr->pending_queue);

		TAILQ_REMOVE(&wptr->pending_queue, io, retry_entry);



		if (ftl_submit_write(wptr, io) == -EAGAIN) {

			return 0;

		}

		wptr->current_io = NULL;

	}



	/* Make sure the band is prepared for writing */