Re: ehci dynamic debug problem

Alan Stern
2012-04-13T18:14:02Z

On Fri, 13 Apr 2012, Johannes Stezenbach wrote:

> > But there is no such thing as dynamic debug for ehci, is there?
> > There's a separate dynamic debug setting for each dev_dbg statement.
> > So your ideal solution makes no sense.
>
> When CONFIG_DYNAMIC_DEBUG=y but ehci debug is disabled

There is no such thing as ehci debug! So how can it be disabled?
There's only an individual setting for each line of debugging code.

> in /sys/kernel/debug/dynamic_debug/control, then
> dbg_port() calls dbg_port_buf() which would
> format the string, then calls ehci_dbg() which
> calls dev_dbg() which discards it.
>
> Does it make sense now?

No. What happens if dynamic debug is enabled for one line that calls
dbg_port_buf() but not for another? There's no way to avoid the string
formatting in both lines, even though one of them discards the result.

Alan Stern