Re: Slow boot due perhaps to locks in mouse and platform system

[Arjan van de Ven <arjan@infradead.org>]

On Tue, 14 Oct 2008 11:48:37 -0400
Dmitry Torokhov <dmitry.torokhov@gmail.com> wrote:

> On Tue, Oct 14, 2008 at 11:37:49AM -0400, Arjan van de Ven wrote:
> > On Tue, 14 Oct 2008 11:29:55 -0400
> > Dmitry Torokhov <dmitry.torokhov@gmail.com> wrote:
> > 
> > > On Tue, Oct 14, 2008 at 11:12:36AM -0400, Arjan van de Ven wrote:
> > > > On Tue, 14 Oct 2008 10:54:36 -0400
> > > > Dmitry Torokhov <dmitry.torokhov@gmail.com> wrote:
> > > > > On Tue, Oct 14, 2008 at 03:19:28PM +0100, Phil Endecott wrote:
> > > > > > What can be done about this?  Is it unreasonable for the
> > > > > > mouse probing to take 2 seconds?  Should it not be holding
> > > > > > the conflicting lock while it is probing?  Does the platform
> > > > > > matching code really need to hold the lock when it's just
> > > > > > comparing the string names of the device and driver?
> > > > > >
> > > > 
> > > > the real thing is to not wait on this while booting;
> > > > my fastboot git tree has the patches to fix that part..
> > > > 
> > > 
> > > Could you please be more specific?
> > \
> > oh btw you could make the mouse be exempt from this waiting that'd
> > be a much simpler/nicer solution ;-)
> > 
> 
> Like I said, mouse probing is done in kseriod which is a separate
> thread. If you look at the trace psmouse_init returned way way before,
> its pcspkr got stuck for some reason (after completing
> pcspkr_probe)...
but without that locking issue we still have the delay.
Because you run as a probe, and the kernel code waits until ALL probes
are done:
        /* wait for the known devices to complete their probing */
        while (driver_probe_done() != 0)
                msleep(100);


if the serio stuff wouldn't run as a "probe"... we wouldn't wait on it 
before mounting the root fs.

(and whoever comes up with "but I have my root fs on my mouse....
"LALALALALALA" <fingers in ears>)


> 


-- 
Arjan van de Ven 	Intel Open Source Technology Centre
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