Commit 8832cf92 authored by Sagi Grimberg's avatar Sagi Grimberg Committed by Christoph Hellwig
Browse files

nvmet: use a private workqueue instead of the system workqueue 



Any attempt to flush kernel-global WQs has possibility of deadlock
so we should simply stop using them, instead introduce nvmet_wq
which is the generic nvmet workqueue for work elements that
don't explicitly require a dedicated workqueue (by the mere fact
that they are using the system_wq).

Changes were done using the following replaces:

 - s/schedule_work(/queue_work(nvmet_wq, /g
 - s/schedule_delayed_work(/queue_delayed_work(nvmet_wq, /g
 - s/flush_scheduled_work()/flush_workqueue(nvmet_wq)/g

Reported-by: default avatarTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: default avatarSagi Grimberg <sagi@grimberg.me>
Reviewed-by: default avatarChaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
parent bc360b0b

drivers/nvme/target/admin-cmd.c

+1 −1
Original line number Diff line number Diff line
@@ -988,7 +988,7 @@ void nvmet_execute_async_event(struct nvmet_req *req) 
	ctrl->async_event_cmds[ctrl->nr_async_event_cmds++] = req;

	mutex_unlock(&ctrl->lock);



	schedule_work(&ctrl->async_event_work);

	queue_work(nvmet_wq, &ctrl->async_event_work);

}



void nvmet_execute_keep_alive(struct nvmet_req *req)

drivers/nvme/target/configfs.c

+1 −1
Original line number Diff line number Diff line
@@ -1593,7 +1593,7 @@ static void nvmet_port_release(struct config_item *item) 
	struct nvmet_port *port = to_nvmet_port(item);



	/* Let inflight controllers teardown complete */

	flush_scheduled_work();

	flush_workqueue(nvmet_wq);

	list_del(&port->global_entry);



	kfree(port->ana_state);

drivers/nvme/target/core.c

+18 −6
Original line number Diff line number Diff line
@@ -20,6 +20,9 @@ struct workqueue_struct *zbd_wq; 
static const struct nvmet_fabrics_ops *nvmet_transports[NVMF_TRTYPE_MAX];

static DEFINE_IDA(cntlid_ida);



struct workqueue_struct *nvmet_wq;

EXPORT_SYMBOL_GPL(nvmet_wq);



/*

 * This read/write semaphore is used to synchronize access to configuration

 * information on a target system that will result in discovery log page
@@ -205,7 +208,7 @@ void nvmet_add_async_event(struct nvmet_ctrl *ctrl, u8 event_type, 
	list_add_tail(&aen->entry, &ctrl->async_events);

	mutex_unlock(&ctrl->lock);



	schedule_work(&ctrl->async_event_work);

	queue_work(nvmet_wq, &ctrl->async_event_work);

}



static void nvmet_add_to_changed_ns_log(struct nvmet_ctrl *ctrl, __le32 nsid)
@@ -385,7 +388,7 @@ static void nvmet_keep_alive_timer(struct work_struct *work) 
	if (reset_tbkas) {

		pr_debug("ctrl %d reschedule traffic based keep-alive timer\n",

			ctrl->cntlid);

		schedule_delayed_work(&ctrl->ka_work, ctrl->kato * HZ);

		queue_delayed_work(nvmet_wq, &ctrl->ka_work, ctrl->kato * HZ);

		return;

	}
@@ -403,7 +406,7 @@ void nvmet_start_keep_alive_timer(struct nvmet_ctrl *ctrl) 
	pr_debug("ctrl %d start keep-alive timer for %d secs\n",

		ctrl->cntlid, ctrl->kato);



	schedule_delayed_work(&ctrl->ka_work, ctrl->kato * HZ);

	queue_delayed_work(nvmet_wq, &ctrl->ka_work, ctrl->kato * HZ);

}



void nvmet_stop_keep_alive_timer(struct nvmet_ctrl *ctrl)
@@ -1478,7 +1481,7 @@ void nvmet_ctrl_fatal_error(struct nvmet_ctrl *ctrl) 
	mutex_lock(&ctrl->lock);

	if (!(ctrl->csts & NVME_CSTS_CFS)) {

		ctrl->csts |= NVME_CSTS_CFS;

		schedule_work(&ctrl->fatal_err_work);

		queue_work(nvmet_wq, &ctrl->fatal_err_work);

	}

	mutex_unlock(&ctrl->lock);

}
@@ -1620,9 +1623,15 @@ static int __init nvmet_init(void) 
		goto out_free_zbd_work_queue;

	}



	nvmet_wq = alloc_workqueue("nvmet-wq", WQ_MEM_RECLAIM, 0);

	if (!nvmet_wq) {

		error = -ENOMEM;

		goto out_free_buffered_work_queue;

	}



	error = nvmet_init_discovery();

	if (error)

		goto out_free_work_queue;

		goto out_free_nvmet_work_queue;



	error = nvmet_init_configfs();

	if (error)
@@ -1631,7 +1640,9 @@ static int __init nvmet_init(void) 


out_exit_discovery:

	nvmet_exit_discovery();

out_free_work_queue:

out_free_nvmet_work_queue:

	destroy_workqueue(nvmet_wq);

out_free_buffered_work_queue:

	destroy_workqueue(buffered_io_wq);

out_free_zbd_work_queue:

	destroy_workqueue(zbd_wq);
@@ -1643,6 +1654,7 @@ static void __exit nvmet_exit(void) 
	nvmet_exit_configfs();

	nvmet_exit_discovery();

	ida_destroy(&cntlid_ida);

	destroy_workqueue(nvmet_wq);

	destroy_workqueue(buffered_io_wq);

	destroy_workqueue(zbd_wq);

drivers/nvme/target/fc.c

+4 −4
Original line number Diff line number Diff line
@@ -1491,7 +1491,7 @@ __nvmet_fc_free_assocs(struct nvmet_fc_tgtport *tgtport) 
	list_for_each_entry_rcu(assoc, &tgtport->assoc_list, a_list) {

		if (!nvmet_fc_tgt_a_get(assoc))

			continue;

		if (!schedule_work(&assoc->del_work))

		if (!queue_work(nvmet_wq, &assoc->del_work))

			/* already deleting - release local reference */

			nvmet_fc_tgt_a_put(assoc);

	}
@@ -1546,7 +1546,7 @@ nvmet_fc_invalidate_host(struct nvmet_fc_target_port *target_port, 
			continue;

		assoc->hostport->invalid = 1;

		noassoc = false;

		if (!schedule_work(&assoc->del_work))

		if (!queue_work(nvmet_wq, &assoc->del_work))

			/* already deleting - release local reference */

			nvmet_fc_tgt_a_put(assoc);

	}
@@ -1592,7 +1592,7 @@ nvmet_fc_delete_ctrl(struct nvmet_ctrl *ctrl) 
		nvmet_fc_tgtport_put(tgtport);



		if (found_ctrl) {

			if (!schedule_work(&assoc->del_work))

			if (!queue_work(nvmet_wq, &assoc->del_work))

				/* already deleting - release local reference */

				nvmet_fc_tgt_a_put(assoc);

			return;
@@ -2060,7 +2060,7 @@ nvmet_fc_rcv_ls_req(struct nvmet_fc_target_port *target_port, 
	iod->rqstdatalen = lsreqbuf_len;

	iod->hosthandle = hosthandle;



	schedule_work(&iod->work);

	queue_work(nvmet_wq, &iod->work);



	return 0;

}

drivers/nvme/target/fcloop.c

+8 −8
Original line number Diff line number Diff line
@@ -360,7 +360,7 @@ fcloop_h2t_ls_req(struct nvme_fc_local_port *localport, 
		spin_lock(&rport->lock);

		list_add_tail(&rport->ls_list, &tls_req->ls_list);

		spin_unlock(&rport->lock);

		schedule_work(&rport->ls_work);

		queue_work(nvmet_wq, &rport->ls_work);

		return ret;

	}
@@ -393,7 +393,7 @@ fcloop_h2t_xmt_ls_rsp(struct nvmet_fc_target_port *targetport, 
		spin_lock(&rport->lock);

		list_add_tail(&rport->ls_list, &tls_req->ls_list);

		spin_unlock(&rport->lock);

		schedule_work(&rport->ls_work);

		queue_work(nvmet_wq, &rport->ls_work);

	}



	return 0;
@@ -448,7 +448,7 @@ fcloop_t2h_ls_req(struct nvmet_fc_target_port *targetport, void *hosthandle, 
		spin_lock(&tport->lock);

		list_add_tail(&tport->ls_list, &tls_req->ls_list);

		spin_unlock(&tport->lock);

		schedule_work(&tport->ls_work);

		queue_work(nvmet_wq, &tport->ls_work);

		return ret;

	}
@@ -480,7 +480,7 @@ fcloop_t2h_xmt_ls_rsp(struct nvme_fc_local_port *localport, 
		spin_lock(&tport->lock);

		list_add_tail(&tport->ls_list, &tls_req->ls_list);

		spin_unlock(&tport->lock);

		schedule_work(&tport->ls_work);

		queue_work(nvmet_wq, &tport->ls_work);

	}



	return 0;
@@ -520,7 +520,7 @@ fcloop_tgt_discovery_evt(struct nvmet_fc_target_port *tgtport) 
	tgt_rscn->tport = tgtport->private;

	INIT_WORK(&tgt_rscn->work, fcloop_tgt_rscn_work);



	schedule_work(&tgt_rscn->work);

	queue_work(nvmet_wq, &tgt_rscn->work);

}



static void
@@ -739,7 +739,7 @@ fcloop_fcp_req(struct nvme_fc_local_port *localport, 
	INIT_WORK(&tfcp_req->tio_done_work, fcloop_tgt_fcprqst_done_work);

	kref_init(&tfcp_req->ref);



	schedule_work(&tfcp_req->fcp_rcv_work);

	queue_work(nvmet_wq, &tfcp_req->fcp_rcv_work);



	return 0;

}
@@ -921,7 +921,7 @@ fcloop_fcp_req_release(struct nvmet_fc_target_port *tgtport, 
{

	struct fcloop_fcpreq *tfcp_req = tgt_fcp_req_to_fcpreq(tgt_fcpreq);



	schedule_work(&tfcp_req->tio_done_work);

	queue_work(nvmet_wq, &tfcp_req->tio_done_work);

}



static void
@@ -976,7 +976,7 @@ fcloop_fcp_abort(struct nvme_fc_local_port *localport, 


	if (abortio)

		/* leave the reference while the work item is scheduled */

		WARN_ON(!schedule_work(&tfcp_req->abort_rcv_work));

		WARN_ON(!queue_work(nvmet_wq, &tfcp_req->abort_rcv_work));

	else  {

		/*

		 * as the io has already had the done callback made,