On 30 March 2016 at 22:10, <[email protected]> wrote: > From: Ben Greear <[email protected]> > > I believe the CE tx buffer reaping logic may be able to fall > behind in certain cases (lots of serial console logging, lots > of WMI messages). > > Dropping WMI messages is a very serious problem, so it is worth > waiting a bit in hopes the tx buffers become available again. > > Signed-off-by: Ben Greear <[email protected]> > --- > > Probably the ath10k_err should be made dbg or rate-limited before > this goes upstream..in meantime, it might help shed some light on > this problem. > > drivers/net/wireless/ath/ath10k/wmi.c | 15 ++++++++++++++- > 1 file changed, 14 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/wireless/ath/ath10k/wmi.c > b/drivers/net/wireless/ath/ath10k/wmi.c > index f042711..43d23fc 100644 > --- a/drivers/net/wireless/ath/ath10k/wmi.c > +++ b/drivers/net/wireless/ath/ath10k/wmi.c > @@ -1819,6 +1819,7 @@ static void ath10k_wmi_op_ep_tx_credits(struct ath10k > *ar) > int ath10k_wmi_cmd_send(struct ath10k *ar, struct sk_buff *skb, u32 cmd_id) > { > int ret = -EOPNOTSUPP; > + int retry = 1000; > > might_sleep(); > > @@ -1832,7 +1833,19 @@ int ath10k_wmi_cmd_send(struct ath10k *ar, struct > sk_buff *skb, u32 cmd_id) > /* try to send pending beacons first. they take priority */ > ath10k_wmi_tx_beacons_nowait(ar); > > - ret = ath10k_wmi_cmd_send_nowait(ar, skb, cmd_id); > + while (--retry) { > + ret = ath10k_wmi_cmd_send_nowait(ar, skb, cmd_id); > + if ((ret == -ENOBUFS) && > + !test_bit(ATH10K_FLAG_CRASH_FLUSH, > &ar->dev_flags)) { > + /* CE transport logic is full, maybe we > cannot reap entries fast > + * enough? > + */ > + ath10k_err(ar, "CE transport is full, > sleeping for 1ms\n"); > + msleep(1); > + continue; > + } > + break; > + }
This looks like a workaround to me. This problem shouldn't be happening in the first place as far as design is concerned. If it does the only reason I can think of is if MSI-range support is exercised. Anyway, It'd be a lot more sane to instead poll WMI's CE Tx pipe when processing WMI's CE Rx pipe (but that's still -arguably- unnecessary) instead of retrying in WMI.. Michał _______________________________________________ ath10k mailing list [email protected] http://lists.infradead.org/mailman/listinfo/ath10k
