[PATCH 1/2] nvme-tcp: short-circuit connect retries

Hannes Reinecke
2022-07-14T12:45:17Z

So pass the actual error status to nvme_tcp_reconnect_or_remove()
and short-circuit retries if the DNR bit is set.

Signed-off-by: Hannes Reinecke <hare@suse.de>
---
drivers/nvme/host/tcp.c | 25 ++++++++++++++++++-------
1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
index 70096a2e8762..4220c1ad6b29 100644
--- a/drivers/nvme/host/tcp.c
+++ b/drivers/nvme/host/tcp.c
@@ -2065,8 +2065,10 @@ static void nvme_tcp_teardown_io_queues(struct nvme_ctrl *ctrl,
nvme_tcp_destroy_io_queues(ctrl, remove);
}

-static void nvme_tcp_reconnect_or_remove(struct nvme_ctrl *ctrl)
+static void nvme_tcp_reconnect_or_remove(struct nvme_ctrl *ctrl, int status)
{
+ bool recon = true;
+
/* If we are resetting/deleting then do nothing */
if (ctrl->state != NVME_CTRL_CONNECTING) {
WARN_ON_ONCE(ctrl->state == NVME_CTRL_NEW ||
@@ -2074,7 +2076,12 @@ static void nvme_tcp_reconnect_or_remove(struct nvme_ctrl *ctrl)
return;
}

- if (nvmf_should_reconnect(ctrl)) {
+ if (status > 0 && (status & NVME_SC_DNR)) {
+ dev_info(ctrl->device, "reconnect failure %d\n", status);
+ recon = false;
+ }
+
+ if (recon && nvmf_should_reconnect(ctrl)) {
dev_info(ctrl->device, "Reconnecting in %d seconds...\n",
ctrl->opts->reconnect_delay);
queue_delayed_work(nvme_wq, &to_tcp_ctrl(ctrl)->connect_work,
@@ -2162,10 +2169,12 @@ static void nvme_tcp_reconnect_ctrl_work(struct work_struct *work)
struct nvme_tcp_ctrl *tcp_ctrl = container_of(to_delayed_work(work),
struct nvme_tcp_ctrl, connect_work);
struct nvme_ctrl *ctrl = &tcp_ctrl->ctrl;
+ int ret;

++ctrl->nr_reconnects;

- if (nvme_tcp_setup_ctrl(ctrl, false))
+ ret = nvme_tcp_setup_ctrl(ctrl, false);
+ if (ret)
goto requeue;

dev_info(ctrl->device, "Successfully reconnected (%d attempt)\n",
@@ -2178,7 +2187,7 @@ static void nvme_tcp_reconnect_ctrl_work(struct work_struct *work)
requeue:
dev_info(ctrl->device, "Failed reconnect attempt %d\n",
ctrl->nr_reconnects);
- nvme_tcp_reconnect_or_remove(ctrl);
+ nvme_tcp_reconnect_or_remove(ctrl, ret);
}

static void nvme_tcp_error_recovery_work(struct work_struct *work)
@@ -2203,7 +2212,7 @@ static void nvme_tcp_error_recovery_work(struct work_struct *work)
return;
}

- nvme_tcp_reconnect_or_remove(ctrl);
+ nvme_tcp_reconnect_or_remove(ctrl, -ENOTCONN);
}

static void nvme_tcp_teardown_ctrl(struct nvme_ctrl *ctrl, bool shutdown)
@@ -2229,6 +2238,7 @@ static void nvme_reset_ctrl_work(struct work_struct *work)
{
struct nvme_ctrl *ctrl =
container_of(work, struct nvme_ctrl, reset_work);
+ int ret;

nvme_stop_ctrl(ctrl);
nvme_tcp_teardown_ctrl(ctrl, false);
@@ -2240,14 +2250,15 @@ static void nvme_reset_ctrl_work(struct work_struct *work)
return;
}

- if (nvme_tcp_setup_ctrl(ctrl, false))
+ ret = nvme_tcp_setup_ctrl(ctrl, false);
+ if (ret)
goto out_fail;

return;

out_fail:
++ctrl->nr_reconnects;
- nvme_tcp_reconnect_or_remove(ctrl);
+ nvme_tcp_reconnect_or_remove(ctrl, ret);
}

static void nvme_tcp_free_ctrl(struct nvme_ctrl *nctrl)
--
2.29.2