> > Now I'm going to have a look at the ehci USB2.0 driver; I seems that it > > needs > > 5 seconds to "initialize" (time spent between the "npe: .. ehci0" message > > and "genunix: ehci0 is ..."). > > > > And the USB disk that happens to be connected to that ehci USB 2.0 > > controller > > delays the boot by another five seconds... > > Which makes me wonder, is there anything we can do to "background" > certain device detection probing so that the login > process can start?
The comments in i_ddi_forceattach_drivers() explains why this isn't done for ehci/uhci/ohci: http://src.opensolaris.org/source/s?defs=i_ddi_forceattach_drivers 3165 void 3166 i_ddi_forceattach_drivers() 3167 { 3168 /* 3169 * On i386, the USB drivers need to load and take over from the 3170 * SMM BIOS drivers ASAP after consconfig(), so make sure they 3171 * get loaded right here rather than letting the thread do it. 3172 * 3173 * The order here is important. EHCI must be loaded first, as 3174 * we have observed many systems on which hangs occur if the 3175 * {U,O}HCI companion controllers take over control from the BIOS 3176 * before EHCI does. These hangs are also caused by BIOSes leaving 3177 * interrupt-on-port-change enabled in the ehci controller, so that 3178 * when uhci/ohci reset themselves, it induces a port change on 3179 * the ehci companion controller. Since there's no interrupt handler 3180 * installed at the time, the moment that interrupt is unmasked, an 3181 * interrupt storm will occur. All this is averted when ehci is 3182 * loaded first. And now you know..... the REST of the story. 3183 * 3184 * Regardless of platform, ehci needs to initialize first to avoid 3185 * unnecessary connects and disconnects on the companion controller 3186 * when ehci sets up the routing. 3187 */ 3188 (void) ddi_hold_installed_driver(ddi_name_to_major("ehci")); 3189 (void) ddi_hold_installed_driver(ddi_name_to_major("uhci")); 3190 (void) ddi_hold_installed_driver(ddi_name_to_major("ohci")); 3191 > In other words, do we really need to delay the boot process to detect > USB storage devices unless one of the devices is required to be > mounted *at boot* or is the boot device itself? No, the USB 2.0 HDD that is connected to by system at boot time isn't the boot device itself. Attaching the scsa2usb driver early during boot time seems to just a side effect of force-attaching the ehci driver, which will enumerate the USB devices connected to that usb controller. This message posted from opensolaris.org _______________________________________________ perf-discuss mailing list perf-discuss@opensolaris.org
