[PATCH AUTOSEL 5.4 10/12] nvme: introduce helper function to get ctrl state

[Sasha Levin]

From: Keith Busch <kbusch@xxxxxxxxxx>

[ Upstream commit 5c687c287c46fadb14644091823298875a5216aa ]

The controller state is typically written by another CPU, so reading it
should ensure no optimizations are taken. This is a repeated pattern in
the driver, so start with adding a convenience function that returns the
controller state with READ_ONCE().

Reviewed-by: Sagi Grimberg <sagi@xxxxxxxxxxx>
Signed-off-by: Keith Busch <kbusch@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/nvme/host/nvme.h | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index 17c0d6ae3eeeb..c492d7d323987 100644
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -292,6 +292,11 @@ struct nvme_ctrl {
 	struct nvme_fault_inject fault_inject;
 };
 
+static inline enum nvme_ctrl_state nvme_ctrl_state(struct nvme_ctrl *ctrl)
+{
+	return READ_ONCE(ctrl->state);
+}
+
 enum nvme_iopolicy {
 	NVME_IOPOLICY_NUMA,
 	NVME_IOPOLICY_RR,
-- 
2.42.0