Re: usbmon: Extended text API
"Jon Smirl" <[email protected]>
| Newsgroups | gmane.linux.usb.devel |
|---|---|
| Message-ID | <[email protected]> |
On 2/26/07, Alan Stern <[email protected]> wrote: > On Mon, 26 Feb 2007, Jon Smirl wrote: > > > My instability seems to come from a race between EHCI and UHCI. I have > > one EHCI and four UHCI host controllers (ICH5). > > > > I usually get this at boot: > > bus 1 UHCI-A > > bus 2 UHCI-B > > bus 3 UHCI-C > > bus 4 UHCI-D > > bus 5 EHCI > > > > But occasionally I get this. I don't see a pattern, it feels like a race. > > bus 1 EHCI > > bus 2 UHCI-A > > bus 3 UHCI-B > > bus 4 UHCI-C > > bus 5 UHCI-D > > > > My USB is all loading as modules. I don't see any option to control > > parallel PCI probing in 2.6.20. > > The option is called CONFIG_PCI_MULTITHREAD_PROBE, and it is marked BROKEN > in 2.6.20. So it's probably not the reason. More likely you're just up > against an ordinary race. At some point in the boot process udev starts > up, it spawns lots of modprobe tasks all running at the same time, and any > one of them could end up beating the others. > > You could remove this indeterminism by explicitly loading ehci-hcd and > uhci-hcd (that is the preferred order) in a system start-up script before > udev. In FC6, for example, the modules are loaded from an initramfs > script. In think the usb modules on initramfs with Unbuntu, but they must not be proloading them with a script. But doesn't loading from a script defeat the mechanism of only loading what modules you need? Another way to control this would be to put all of the USB Host IDs into a single module (usbcore), and then that module would load in ehci, uhci, etc. -- Jon Smirl [email protected] ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel