Commit f7ed8cd6 authored by Ankit Kumar's avatar Ankit Kumar Committed by Konrad Sztyber
Browse files

lib/nvme: eventfd to handle disconnected I/O qpair 



In poll mode the process completion API checks for the disconnected
queue pair and calls the specified disconnected_qpair_cb function. In
interrupt mode we need a way to notify the application in case of
disconnected queue pair.
Register an eventfd to the epoll file descriptor of nvme poll group. This
fd will be written after a queue pair disconnection. Thus the next event
on poll group will handle the queue pair disconnection.

Change-Id: I481eeb847c22e710d8e9705c4ea3e9267da93876
Signed-off-by: default avatarAnkit Kumar <ankit.kumar@samsung.com>
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/25387


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Community-CI: Community CI Samsung <spdk.community.ci.samsung@gmail.com>
Community-CI: Broadcom CI <spdk-ci.pdl@broadcom.com>
Community-CI: Mellanox Build Bot
Reviewed-by: default avatarKonrad Sztyber <konrad.sztyber@intel.com>
Reviewed-by: default avatarJim Harris <jim.harris@samsung.com>
parent 6de68644

lib/nvme/nvme_internal.h

+2 −0
Original line number Diff line number Diff line
@@ -539,6 +539,7 @@ struct spdk_nvme_poll_group { 
	bool						in_process_completions;

	bool						enable_interrupts;

	bool						enable_interrupts_is_valid;

	int						disconnect_qpair_fd;

	struct spdk_fd_group				*fgrp;

};
@@ -1234,6 +1235,7 @@ nvme_ctrlr_unlock(struct spdk_nvme_ctrlr *ctrlr) 
/* Poll group management functions. */

int nvme_poll_group_connect_qpair(struct spdk_nvme_qpair *qpair);

int nvme_poll_group_disconnect_qpair(struct spdk_nvme_qpair *qpair);

void nvme_poll_group_write_disconnect_qpair_fd(struct spdk_nvme_poll_group *group);



/* Admin functions */

int	nvme_ctrlr_cmd_identify(struct spdk_nvme_ctrlr *ctrlr,

lib/nvme/nvme_poll_group.c

+76 −2
Original line number Diff line number Diff line
@@ -70,6 +70,7 @@ spdk_nvme_poll_group_create(void *ctx, struct spdk_nvme_accel_fn_table *table) 
#endif

	}



	group->disconnect_qpair_fd = -1;

	group->ctx = ctx;

	STAILQ_INIT(&group->tgroups);
@@ -102,11 +103,73 @@ spdk_nvme_qpair_get_optimal_poll_group(struct spdk_nvme_qpair *qpair) 
	return tgroup->group;

}



#ifdef __linux__

static int

nvme_poll_group_read_disconnect_qpair_fd(void *arg)

{

	return 0;

}



void

nvme_poll_group_write_disconnect_qpair_fd(struct spdk_nvme_poll_group *group)

{

	uint64_t notify = 1;

	int rc;



	if (!group->enable_interrupts) {

		return;

	}



	/* Write to the disconnect qpair fd. This will generate event on the epoll fd of poll

	 * group. We then check for disconnected qpairs in spdk_nvme_poll_group_wait() */

	rc = write(group->disconnect_qpair_fd, &notify, sizeof(notify));

	if (rc < 0) {

		SPDK_ERRLOG("failed to write the disconnect qpair fd: %s.\n", strerror(errno));

	}

}



static int

nvme_poll_group_add_disconnect_qpair_fd(struct spdk_nvme_poll_group *group)

{

	struct spdk_event_handler_opts opts = {};

	int fd;



	fd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);

	if (fd < 0) {

		return fd;

	}



	assert(group->disconnect_qpair_fd == -1);

	group->disconnect_qpair_fd = fd;



	spdk_fd_group_get_default_event_handler_opts(&opts, sizeof(opts));

	opts.fd_type = SPDK_FD_TYPE_EVENTFD;



	return SPDK_FD_GROUP_ADD_EXT(group->fgrp, fd, nvme_poll_group_read_disconnect_qpair_fd,

				     group, &opts);

}



#else



void

nvme_poll_group_write_disconnect_qpair_fd(struct spdk_nvme_poll_group *group)

{

}



static int

nvme_poll_group_add_disconnect_qpair_fd(struct spdk_nvme_poll_group *group)

{

	return -ENOTSUP;

}



#endif



int

spdk_nvme_poll_group_add(struct spdk_nvme_poll_group *group, struct spdk_nvme_qpair *qpair)

{

	struct spdk_nvme_transport_poll_group *tgroup;

	const struct spdk_nvme_transport *transport;

	int rc;



	if (nvme_qpair_get_state(qpair) != NVME_QPAIR_DISCONNECTED) {

		return -EINVAL;
@@ -115,6 +178,12 @@ spdk_nvme_poll_group_add(struct spdk_nvme_poll_group *group, struct spdk_nvme_qp 
	if (!group->enable_interrupts_is_valid) {

		group->enable_interrupts_is_valid = true;

		group->enable_interrupts = qpair->ctrlr->opts.enable_interrupts;

		if (group->enable_interrupts) {

			rc = nvme_poll_group_add_disconnect_qpair_fd(group);

			if (rc != 0) {

				return rc;

			}

		}

	} else if (qpair->ctrlr->opts.enable_interrupts != group->enable_interrupts) {

		SPDK_ERRLOG("Queue pair %s interrupts cannot be added to poll group\n",

			    qpair->ctrlr->opts.enable_interrupts ? "without" : "with");
@@ -333,6 +402,7 @@ int 
spdk_nvme_poll_group_destroy(struct spdk_nvme_poll_group *group)

{

	struct spdk_nvme_transport_poll_group *tgroup, *tmp_tgroup;

	struct spdk_fd_group *fgrp = group->fgrp;



	STAILQ_FOREACH_SAFE(tgroup, &group->tgroups, link, tmp_tgroup) {

		STAILQ_REMOVE(&group->tgroups, tgroup, spdk_nvme_transport_poll_group, link);
@@ -343,8 +413,12 @@ spdk_nvme_poll_group_destroy(struct spdk_nvme_poll_group *group) 


	}



	if (group->fgrp) {

		spdk_fd_group_destroy(group->fgrp);

	if (fgrp) {

		if (group->enable_interrupts) {

			spdk_fd_group_remove(fgrp, group->disconnect_qpair_fd);

			close(group->disconnect_qpair_fd);

		}

		spdk_fd_group_destroy(fgrp);

	}



	free(group);

lib/nvme/nvme_transport.c

+7 −0
Original line number Diff line number Diff line
@@ -589,6 +589,13 @@ nvme_transport_ctrlr_disconnect_qpair_done(struct spdk_nvme_qpair *qpair) 
		nvme_qpair_abort_all_queued_reqs(qpair);

	}

	nvme_qpair_set_state(qpair, NVME_QPAIR_DISCONNECTED);



	/* In interrupt mode qpairs that are added to poll group need an event for the

	 * disconnected qpairs handling to kick in.

	 */

	if (qpair->poll_group) {

		nvme_poll_group_write_disconnect_qpair_fd(qpair->poll_group->group);

	}

}



int