| From: Stanislaw Gruszka <sgruszka@redhat.com> |
| Date: Wed, 4 Jul 2012 13:10:02 +0200 |
| Subject: rt2x00usb: fix indexes ordering on RX queue kick |
| |
| commit efd821182cec8c92babef6e00a95066d3252fda4 upstream. |
| |
| On rt2x00_dmastart() we increase index specified by Q_INDEX and on |
| rt2x00_dmadone() we increase index specified by Q_INDEX_DONE. So entries |
| between Q_INDEX_DONE and Q_INDEX are those we currently process in the |
| hardware. Entries between Q_INDEX and Q_INDEX_DONE are those we can |
| submit to the hardware. |
| |
| According to that fix rt2x00usb_kick_queue(), as we need to submit RX |
| entries that are not processed by the hardware. It worked before only |
| for empty queue, otherwise was broken. |
| |
| Note that for TX queues indexes ordering are ok. We need to kick entries |
| that have filled skb, but was not submitted to the hardware, i.e. |
| started from Q_INDEX_DONE and have ENTRY_DATA_PENDING bit set. |
| |
| From practical standpoint this fixes RX queue stall, usually reproducible |
| in AP mode, like for example reported here: |
| https://bugzilla.redhat.com/show_bug.cgi?id=828824 |
| |
| Reported-and-tested-by: Franco Miceli <fmiceli@plan.ceibal.edu.uy> |
| Reported-and-tested-by: Tom Horsley <horsley1953@gmail.com> |
| Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> |
| Signed-off-by: John W. Linville <linville@tuxdriver.com> |
| Signed-off-by: Ben Hutchings <ben@decadent.org.uk> |
| --- |
| drivers/net/wireless/rt2x00/rt2x00usb.c | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| diff --git a/drivers/net/wireless/rt2x00/rt2x00usb.c b/drivers/net/wireless/rt2x00/rt2x00usb.c |
| index d357d1e..74ecc33 100644 |
| --- a/drivers/net/wireless/rt2x00/rt2x00usb.c |
| +++ b/drivers/net/wireless/rt2x00/rt2x00usb.c |
| @@ -436,8 +436,8 @@ void rt2x00usb_kick_queue(struct data_queue *queue) |
| case QID_RX: |
| if (!rt2x00queue_full(queue)) |
| rt2x00queue_for_each_entry(queue, |
| - Q_INDEX_DONE, |
| Q_INDEX, |
| + Q_INDEX_DONE, |
| NULL, |
| rt2x00usb_kick_rx_entry); |
| break; |
