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. > Signed-off-by: Todd Brandt <todd.e.brandt@xxxxxxxxxxxxxxx> Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
