Re: [PATCH 2/2] xhci:prevent "callbacks suppressed" when debug is not enabled

From: Dmitry Kasatkin
Date: Fri Aug 16 2013 - 13:38:20 EST


On Fri, Aug 16, 2013 at 8:30 PM, Sarah Sharp <sarah.a.sharp@xxxxxxxxx> wrote:
> On Fri, Aug 16, 2013 at 10:26:35AM -0700, Sarah Sharp wrote:
>> On Thu, Aug 15, 2013 at 05:17:16PM -0700, Greg KH wrote:
>> > On Thu, Aug 15, 2013 at 07:04:55PM +0300, Dmitry Kasatkin wrote:
>> > > When debug is not enabled and dev_dbg() will expand to nothing,
>> > > log might be flooded with "callbacks suppressed". If it was not
>> > > done on purpose, better to use dev_dbg_ratelimited() instead.
>> > >
>> > > Signed-off-by: Dmitry Kasatkin <d.kasatkin@xxxxxxxxxxx>
>> > > ---
>> > > drivers/usb/host/xhci-ring.c | 6 ++----
>> > > 1 file changed, 2 insertions(+), 4 deletions(-)
>> >
>> >
>> > Sarah, does this patch conflict with the trace debug patches being
>> > worked on? I'll hold off on applying it for now, let me know if it's ok
>> > or not.
>>
>> It doesn't conflict with the trace debug patches, because those only
>> effect debugging with xhci_dbg with the host device, not dev_dbg with
>> the USB device. This should apply fine to usb-next.
>
> At another glance, the patch removes two if blocks, but doesn't
> re-indent the rest of the lines:
>
>> @@ -3060,8 +3060,7 @@ int xhci_queue_intr_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
>> * to set the polling interval (once the API is added).
>> */
>> if (xhci_interval != ep_interval) {
>> - if (printk_ratelimit())
>> - dev_dbg(&urb->dev->dev, "Driver uses different interval"
>> + dev_dbg_ratelimited(&urb->dev->dev, "Driver uses different interval"
>> " (%d microframe%s) than xHCI "
>> "(%d microframe%s)\n",
>> ep_interval,
>
> That should probably be fixed.

It actually looks correct when patch is applied.

But it depends what you mean of course.
It looks like it was before:
dev_dbg_ratelimited(&urb->dev->dev, "Driver uses different interval"
" (%d microframe%s) than xHCI "
"(%d microframe%s)\n",
ep_interval,
ep_interval == 1 ? "" : "s",

Or may be you mean:
dev_dbg_ratelimited(&urb->dev->dev, "Driver uses different interval"
" (%d microframe%s) than xHCI "
"(%d microframe%s)\n",
ep_interval,
ep_interval == 1 ? "" : "s",

Thanks,
Dmitry

>
> Sarah Sharp
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