nvme: prevent warning triggered by nvme_stop_keep_alive
Delayed keep alive work is queued on system workqueue and may be cancelled
via nvme_stop_keep_alive from nvme_reset_wq, nvme_fc_wq or nvme_wq.
Check_flush_dependency detects mismatched attributes between the work-queue
context used to cancel the keep alive work and system-wq. Specifically
system-wq does not have the WQ_MEM_RECLAIM flag, whereas the contexts used
to cancel keep alive work have WQ_MEM_RECLAIM flag.
Example warning:
workqueue: WQ_MEM_RECLAIM nvme-reset-wq:nvme_fc_reset_ctrl_work [nvme_fc]
is flushing !WQ_MEM_RECLAIM events:nvme_keep_alive_work [nvme_core]
To avoid the flags mismatch, delayed keep alive work is queued on nvme_wq.
However this creates a secondary concern where work and a request to cancel
that work may be in the same work queue - namely err_work in the rdma and
tcp transports, which will want to flush/cancel the keep alive work which
will now be on nvme_wq.
After reviewing the transports, it looks like err_work can be moved to
nvme_reset_wq. In fact that aligns them better with transition into
RESETTING and performing related reset work in nvme_reset_wq.
Change nvme-rdma and nvme-tcp to perform err_work in nvme_reset_wq.
Signed-off-by: Nigel Kirkland <nigel.kirkland@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
index f8fa5c5..49d4373 100644
--- a/drivers/nvme/host/tcp.c
+++ b/drivers/nvme/host/tcp.c
@@ -422,7 +422,7 @@ static void nvme_tcp_error_recovery(struct nvme_ctrl *ctrl)
if (!nvme_change_ctrl_state(ctrl, NVME_CTRL_RESETTING))
return;
- queue_work(nvme_wq, &to_tcp_ctrl(ctrl)->err_work);
+ queue_work(nvme_reset_wq, &to_tcp_ctrl(ctrl)->err_work);
}
static int nvme_tcp_process_nvme_cqe(struct nvme_tcp_queue *queue,