From: Willem de Bruijn <will...@google.com>
The virtchannel control queue is lossy to avoid deadlock. Ensure that
no losses occur in practice. Detect a full queue, when overflows may
have happened.
In practice, virtchnl is synchronous currenty and messages generally
take a single slot. Using up anywhere near the full ring is not
expected.
Tested: Running several traffic tests and no logs seen in the dmesg
Signed-off-by: Willem de Bruijn <will...@google.com>
Signed-off-by: Manoj Vishwanathan <manojvi...@google.com>
---
drivers/net/ethernet/intel/idpf/idpf_virtchnl.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c
b/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c
index 07239afb285e..1852836d81e4 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c
+++ b/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c
@@ -218,6 +218,15 @@ static int idpf_mb_clean(struct idpf_adapter *adapter)
if (err)
goto err_kfree;
+ /* Warn if messages may have been dropped */
+ if (num_q_msg == IDPF_DFLT_MBX_Q_LEN) {
+ static atomic_t mbx_full = ATOMIC_INIT(0);
+ int cnt;
+
+ cnt = atomic_inc_return(&mbx_full);
+ net_warn_ratelimited("%s: ctlq full (%d)\n", __func__, cnt);
+ }
+
for (i = 0; i < num_q_msg; i++) {
if (!q_msg[i])
continue;
--
2.46.0.76.ge559c4bf1a-goog
