nvme-fc: use separate work queue to avoid warning

When tearing down a controller the following warning is issued:

WARNING: CPU: 0 PID: 30681 at ../kernel/workqueue.c:2418 check_flush_dependency

This happens as the err_work workqueue item is scheduled on the
system workqueue (which has WQ_MEM_RECLAIM not set), but is flushed
from a workqueue which has WQ_MEM_RECLAIM set.

Fix this by providing an FC-NVMe specific workqueue.

Fixes: 4cff280a5f ("nvme-fc: resolve io failures during connect")
Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
This commit is contained in:
Hannes Reinecke 2019-05-03 11:43:52 +02:00 committed by Christoph Hellwig
parent 87fd125344
commit 8730c1ddb6

View file

@ -202,7 +202,7 @@ static LIST_HEAD(nvme_fc_lport_list);
static DEFINE_IDA(nvme_fc_local_port_cnt);
static DEFINE_IDA(nvme_fc_ctrl_cnt);
static struct workqueue_struct *nvme_fc_wq;
/*
* These items are short-term. They will eventually be moved into
@ -2054,7 +2054,7 @@ nvme_fc_error_recovery(struct nvme_fc_ctrl *ctrl, char *errmsg)
*/
if (ctrl->ctrl.state == NVME_CTRL_CONNECTING) {
active = atomic_xchg(&ctrl->err_work_active, 1);
if (!active && !schedule_work(&ctrl->err_work)) {
if (!active && !queue_work(nvme_fc_wq, &ctrl->err_work)) {
atomic_set(&ctrl->err_work_active, 0);
WARN_ON(1);
}
@ -3399,6 +3399,10 @@ static int __init nvme_fc_init_module(void)
{
int ret;
nvme_fc_wq = alloc_workqueue("nvme_fc_wq", WQ_MEM_RECLAIM, 0);
if (!nvme_fc_wq)
return -ENOMEM;
/*
* NOTE:
* It is expected that in the future the kernel will combine
@ -3416,7 +3420,7 @@ static int __init nvme_fc_init_module(void)
ret = class_register(&fc_class);
if (ret) {
pr_err("couldn't register class fc\n");
return ret;
goto out_destroy_wq;
}
/*
@ -3440,6 +3444,9 @@ static int __init nvme_fc_init_module(void)
device_destroy(&fc_class, MKDEV(0, 0));
out_destroy_class:
class_unregister(&fc_class);
out_destroy_wq:
destroy_workqueue(nvme_fc_wq);
return ret;
}
@ -3456,6 +3463,7 @@ static void __exit nvme_fc_exit_module(void)
device_destroy(&fc_class, MKDEV(0, 0));
class_unregister(&fc_class);
destroy_workqueue(nvme_fc_wq);
}
module_init(nvme_fc_init_module);