@@ -148,6 +148,8 @@ static bool rt2800usb_txstatus_timeout(struct rt2x00_dev *rt2x00dev)
return false;
}
+#define TXSTATUS_READ_INTERVAL 1000000
+
static bool rt2800usb_tx_sta_fifo_read_completed(struct rt2x00_dev *rt2x00dev,
int urb_status, u32 tx_status)
{
@@ -176,8 +178,9 @@ static bool rt2800usb_tx_sta_fifo_read_completed(struct rt2x00_dev *rt2x00dev,
queue_work(rt2x00dev->workqueue, &rt2x00dev->txdone_work);
if (rt2800usb_txstatus_pending(rt2x00dev)) {
- /* Read register after 250 us */
- hrtimer_start(&rt2x00dev->txstatus_timer, ktime_set(0, 250000),
+ /* Read register after 1 ms */
+ hrtimer_start(&rt2x00dev->txstatus_timer,
+ ktime_set(0, TXSTATUS_READ_INTERVAL),
HRTIMER_MODE_REL);
return false;
}
@@ -202,8 +205,9 @@ static void rt2800usb_async_read_tx_status(struct rt2x00_dev *rt2x00dev)
if (test_and_set_bit(TX_STATUS_READING, &rt2x00dev->flags))
return;
- /* Read TX_STA_FIFO register after 500 us */
- hrtimer_start(&rt2x00dev->txstatus_timer, ktime_set(0, 500000),
+ /* Read TX_STA_FIFO register after 2 ms */
+ hrtimer_start(&rt2x00dev->txstatus_timer,
+ ktime_set(0, 2*TXSTATUS_READ_INTERVAL),
HRTIMER_MODE_REL);
}
This is a note to let you know that I have just added a patch titled rt2800usb: slow down TX status polling to the linux-3.11.y-queue branch of the 3.11.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.11.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.11.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From 44b18df1e8f5290e05d3f045e3648798288e7100 Mon Sep 17 00:00:00 2001 From: Stanislaw Gruszka <sgruszka@redhat.com> Date: Fri, 18 Oct 2013 11:36:54 +0200 Subject: rt2800usb: slow down TX status polling commit 36165fd5b00bf8163f89c21bb16a3e9834555b10 upstream. Polling TX statuses too frequently has two negative effects. First is randomly peek CPU usage, causing overall system functioning delays. Second bad effect is that device is not able to fill TX statuses in H/W register on some workloads and we get lot of timeouts like below: ieee80211 phy4: rt2800usb_entry_txstatus_timeout: Warning - TX status timeout for entry 7 in queue 2 ieee80211 phy4: rt2800usb_entry_txstatus_timeout: Warning - TX status timeout for entry 7 in queue 2 ieee80211 phy4: rt2800usb_txdone: Warning - Got TX status for an empty queue 2, dropping This not only cause flood of messages in dmesg, but also bad throughput, since rate scaling algorithm can not work optimally. In the future, we should probably make polling interval be adjusted automatically, but for now just increase values, this make mentioned problems gone. Resolve: https://bugzilla.kernel.org/show_bug.cgi?id=62781 Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- drivers/net/wireless/rt2x00/rt2800usb.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) -- 1.8.3.2