On Tue, Oct 02, 2012 at 01:20:58PM -0700, Yinghai Lu wrote: > On Tue, Oct 2, 2012 at 10:47 AM, Greg Kroah-Hartman > <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > > On Tue, Oct 02, 2012 at 10:39:25AM -0700, Yinghai Lu wrote: > >> On Tue, Oct 2, 2012 at 6:33 AM, Greg Kroah-Hartman > >> Those patches address Bjorn's request: > >> 1. kill acpi_pci_root_start in drivers/acpi/pci_root.c > >> 2. register pci device to device as soon as possible, so for_each_pci_device > >> could be used early before pci_bus_add_devices. > >> > >> please check change log patch2-4. > > > > Sorry, I still don't see what is so special about PCI that they have to > > do something different here. What am I missing? > > That is something that core related with hotplug: > > for booting and hotplug, we have different code path. > 1. for booting, all device are enumerated and registered, and later > driver get registered, driver is attached to the devices. > 2. for hotplug, one device on the bus is found, and then registered > and driver is attached, after that > another device on the bus is found, and then > registered and driver is attached... > > The reason for the difference, device driver is not registered later > during booting path. But on each case, the code path in the driver core is the same, and you don't know if for 1) a driver is not already registered in the system (think drivers built into the kernel). > We should make the two path have same sequence. the solution that I > suggest is adding per device drivers_autoprobe. No, now you have 2 code paths in the driver core, do not do that. > and thanking for bus_type notifier that we could toggle that bit > during device_add, so could make all device on same > bus get probed and registered but driver get skipped. and after that > call device_attach for all device at one batch. > > That will remove those hotplug related hacks like acpi_pci_root_start > that try to delay registering of pci devices. > and make the code lesser and readable. I don't know what you are doing in the acpi code, but I do not think it requires a driver core change like this. Again, why is PCI different from any other bus type? (hint, it shouldn't be...) greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
