Commit 06358c25 authored by Konrad Sztyber's avatar Konrad Sztyber Committed by Jim Harris
Browse files

bdev/nvme: use poll_group's fd_group to register interrupts 



This eliminates the need for nesting epoll instances in the kernel and
allows us to skip one epoll_wait() call.  It shows an around 5-10%
latency improvement.

Signed-off-by: default avatarKonrad Sztyber <konrad.sztyber@intel.com>
Change-Id: Idd6ed70d41760566b82246c8af59016fa80a0610
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/25469


Reviewed-by: default avatarBen Walker <ben@nvidia.com>
Community-CI: Community CI Samsung <spdk.community.ci.samsung@gmail.com>
Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarJim Harris <jim.harris@nvidia.com>
Community-CI: Mellanox Build Bot
Reviewed-by: default avatarAnkit Kumar <ankit.kumar@samsung.com>
parent 1ae735a5

module/bdev/nvme/bdev_nvme.c

+15 −15
Original line number Diff line number Diff line
@@ -3750,26 +3750,19 @@ static struct spdk_nvme_accel_fn_table g_bdev_nvme_accel_fn_table = { 
	.abort_sequence		= bdev_nvme_abort_sequence,

};



static int

bdev_nvme_interrupt_wrapper(void *ctx)

static void

bdev_nvme_poll_group_interrupt_cb(struct spdk_nvme_poll_group *group, void *ctx)

{

	int num_events;

	struct nvme_poll_group *group = ctx;



	num_events = spdk_nvme_poll_group_wait(group->group, bdev_nvme_disconnected_qpair_cb);

	if (spdk_unlikely(num_events < 0)) {

		bdev_nvme_check_io_qpairs(group);

	}



	return num_events;

	bdev_nvme_poll(ctx);

}



static int

bdev_nvme_create_poll_group_cb(void *io_device, void *ctx_buf)

{

	struct nvme_poll_group *group = ctx_buf;

	struct spdk_fd_group *fgrp;

	uint64_t period;

	int fd;

	int rc;



	TAILQ_INIT(&group->qpair_list);
@@ -3789,13 +3782,20 @@ bdev_nvme_create_poll_group_cb(void *io_device, void *ctx_buf) 
	if (spdk_interrupt_mode_is_enabled()) {

		spdk_poller_register_interrupt(group->poller, NULL, NULL);



		fd = spdk_nvme_poll_group_get_fd(group->group);

		if (fd < 0) {

		fgrp = spdk_nvme_poll_group_get_fd_group(group->group);

		if (fgrp == NULL) {

			spdk_nvme_poll_group_destroy(group->group);

			return -1;

		}



		rc = spdk_nvme_poll_group_set_interrupt_callback(group->group,

				bdev_nvme_poll_group_interrupt_cb, group);

		if (rc != 0) {

			spdk_nvme_poll_group_destroy(group->group);

			return -1;

		}



		group->intr = SPDK_INTERRUPT_REGISTER(fd, bdev_nvme_interrupt_wrapper, group);

		group->intr = spdk_interrupt_register_fd_group(fgrp, "bdev_nvme_interrupt");

		if (!group->intr) {

			spdk_nvme_poll_group_destroy(group->group);

			return -1;

test/unit/lib/bdev/nvme/bdev_nvme.c/bdev_nvme_ut.c

+5 −2
Original line number Diff line number Diff line
@@ -81,12 +81,15 @@ DEFINE_STUB_V(spdk_keyring_put_key, (struct spdk_key *k)); 
DEFINE_STUB(spdk_key_get_name, const char *, (struct spdk_key *k), NULL);

DEFINE_STUB(spdk_nvme_scan_attached, int, (const struct spdk_nvme_transport_id *trid), 0);



DEFINE_STUB(spdk_nvme_poll_group_get_fd, int, (struct spdk_nvme_poll_group *group), 0);

DEFINE_STUB(spdk_nvme_poll_group_get_fd_group, struct spdk_fd_group *,

	    (struct spdk_nvme_poll_group *group), NULL);

DEFINE_STUB(spdk_nvme_poll_group_wait, int, (struct spdk_nvme_poll_group *group,

		spdk_nvme_disconnected_qpair_cb disconnected_qpair_cb), 0);

DEFINE_STUB(spdk_nvme_ctrlr_get_admin_qp_fd, int, (struct spdk_nvme_ctrlr *ctrlr,

		struct spdk_event_handler_opts *opts), 0);



DEFINE_STUB(spdk_nvme_poll_group_set_interrupt_callback, int,

	    (struct spdk_nvme_poll_group *group,

	     spdk_nvme_poll_group_interrupt_cb cb_fn, void *ctx), 0);

int

spdk_nvme_ctrlr_get_memory_domains(const struct spdk_nvme_ctrlr *ctrlr,

				   struct spdk_memory_domain **domains, int array_size)