Re: ehci dynamic debug problem

From: Alan Stern
Date: Fri Apr 13 2012 - 11:20:16 EST


On Fri, 13 Apr 2012, Johannes Stezenbach wrote:

> On Fri, Apr 13, 2012 at 10:35:59AM -0400, Alan Stern wrote:
> > On Fri, 13 Apr 2012, Johannes Stezenbach wrote:
> > >
> > > Does dynamic debug offer an "is the message two lines below enabled" test?
> > > Simply changing the "#ifdef DEBUG" for dbg_port_buf()
> > > to "#if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG)"
> > > is probably not acceptable due to the overhead of dbg_port_buf()?
> >
> > I don't understand your question. Doesn't dbg_port_buf need to be
> > defined whenever dynamic debugging is enabled?
> >
> > Alternatively, the definition of dbg_port_buf (and related routines) in
> > the !defined(DEBUG) case could be changed; you could add
> >
> > buf[0] = 0;
> >
> > That way you wouldn't get garbage out, although you wouldn't get
> > anything useful either.
>
> The ideal solution I'm looking for gives useful output
> when dynamic debugging is enabled for ehci, but does no
> useless string formatting when CONFIG_DYNAMIC_DEBUG is y
> but the dynamic debug for ehci is disabled.

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.

Alan Stern

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