[PATCH AUTOSEL 5.10 37/39] nvmet: fix false keep-alive timeout when a controller is torn down
From: Sasha Levin <sashal@kernel.org>
Date: 2021-06-03 17:11:19
Also in:
linux-nvme, lkml
Subsystem:
nvm express target driver, the rest · Maintainers:
Christoph Hellwig, Sagi Grimberg, Chaitanya Kulkarni, Linus Torvalds
From: Sagi Grimberg <sagi@grimberg.me> [ Upstream commit aaeadd7075dc9e184bc7876e9dd7b3bada771df2 ] Controller teardown flow may take some time in case it has many I/O queues, and the host may not send us keep-alive during this period. Hence reset the traffic based keep-alive timer so we don't trigger a controller teardown as a result of a keep-alive expiration. Reported-by: Yi Zhang <redacted> Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Reviewed-by: Chaitanya Kulkarni <redacted> Reviewed-by: Hannes Reinecke <hare@suse.de> Tested-by: Yi Zhang <redacted> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sasha Levin <sashal@kernel.org> --- drivers/nvme/target/core.c | 15 +++++++++++---- drivers/nvme/target/nvmet.h | 2 +- 2 files changed, 12 insertions(+), 5 deletions(-)
diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c
index 46e4f7ea34c8..a65a4a810654 100644
--- a/drivers/nvme/target/core.c
+++ b/drivers/nvme/target/core.c@@ -379,10 +379,10 @@ static void nvmet_keep_alive_timer(struct work_struct *work) { struct nvmet_ctrl *ctrl = container_of(to_delayed_work(work), struct nvmet_ctrl, ka_work); - bool cmd_seen = ctrl->cmd_seen; + bool reset_tbkas = ctrl->reset_tbkas; - ctrl->cmd_seen = false; - if (cmd_seen) { + ctrl->reset_tbkas = false; + 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);
@@ -792,6 +792,13 @@ void nvmet_sq_destroy(struct nvmet_sq *sq) percpu_ref_exit(&sq->ref); if (ctrl) { + /* + * The teardown flow may take some time, and the host may not + * send us keep-alive during this period, hence reset the + * traffic based keep-alive timer so we don't trigger a + * controller teardown as a result of a keep-alive expiration. + */ + ctrl->reset_tbkas = true; nvmet_ctrl_put(ctrl); sq->ctrl = NULL; /* allows reusing the queue later */ }
@@ -942,7 +949,7 @@ bool nvmet_req_init(struct nvmet_req *req, struct nvmet_cq *cq, } if (sq->ctrl) - sq->ctrl->cmd_seen = true; + sq->ctrl->reset_tbkas = true; return true;
diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
index ea96487b5424..4bf6d21290c2 100644
--- a/drivers/nvme/target/nvmet.h
+++ b/drivers/nvme/target/nvmet.h@@ -166,7 +166,7 @@ struct nvmet_ctrl { struct nvmet_subsys *subsys; struct nvmet_sq **sqs; - bool cmd_seen; + bool reset_tbkas; struct mutex lock; u64 cap;
--
2.30.2