Re: [PATCH v2] separate usb_address0 mutexes for each bus

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On Sat, May 17, 2014 at 10:43:14AM -0400, Alan Stern wrote:
> On Fri, 16 May 2014, Todd E Brandt wrote:
> 
> > This patch creates a separate instance of the usb_address0 mutex for each USB
> > bus, and attaches it to the usb_bus device struct. This allows devices on
> > separate buses to be enumerated in parallel; saving time.
> > 
> > In the current code, there is a single, global instance of the usb_address0
> > mutex which is used for all devices on all buses. This isn't completely
> > necessary, as this mutex is only needed to prevent address0 collisions for
> > devices on the *same* bus (usb 2.0 spec, sec 4.6.1). This superfluous coverage
> > can cause additional delay in system resume on systems with multiple hosts
> > (up to several seconds depending on what devices are attached).
> > 
> > v2: May 16, 2014
> >  [in response to Greg KH]
> >  - removed kmalloc failure debug prints
> >  [in response to Alan Stern]
> >  - moved the usb_address0_mutex to the usb_bus struct instead of usb_hcd
> >  - no longer mallocing the mutex, it's just statically defined now
> 
> These update descriptions really belong below the "---" tear line.  
> Having them in the final git commit doesn't do any good.

Yea I've already been told that, sorry. I'll do a v3 release with the proper
format changes.

> 
> > Signed-off-by: Todd Brandt <todd.e.brandt@xxxxxxxxxxxxxxx>
> 
> Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
> 
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