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

From: Dmitry Kasatkin
Date: Tue Aug 27 2013 - 13:40:32 EST


On Tue, Aug 27, 2013 at 8:39 PM, Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> On Tue, Aug 27, 2013 at 05:16:37PM +0300, Dmitry Kasatkin wrote:
>> On 16/08/13 20:45, Greg KH wrote:
>> > On Fri, Aug 16, 2013 at 08:38:12PM +0300, Dmitry Kasatkin wrote:
>> >> 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",
>> > No, it should look like:
>> >
>> > 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",
>>
>> Hello. Sorry I was distracted so much from the kernel.
>>
>> But putting string to one line make it much over 80 chars.
>> Is that considered OK?
>
> Yes it is.
>

Ok. I sent PATCHv2 patches couple of hours ago assuming this.

Thanks,
Dmitry


--
Thanks,
Dmitry
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