On Mon, Feb 28, 2005 at 11:46:42AM -0800, Greg KH wrote: > On Sat, Feb 26, 2005 at 06:53:16AM +0100, Kay Sievers wrote: > > This splits the implicit generation of a hotplug events from > > kobject_add() and kobject_del(), to give the user of of these > > functions control over the time the event is created. > > > > The kobject_register() and unregister functions still have the same > > behavior and emit the events by themselves. > > > > The class, block and device core is changed now to emit the hotplug > > event _after_ the "dev" file, the "device" symlink and the default > > attributes are created. This will save udev from spinning in a stat() loop > > to wait for the files to appear, which is expensive if we have a lot of > > concurrent events. > > So, does this solve the issue that everyone has been complaining about > for years with the hotplug event happening before the sysfs files are > present?
I expect most of them, yes. It is not a guarantee, cause drivers can and will create attributes at any time. :) But the most interesting default ones, that people tend to expect at event time will be there _before_ the event happens. To get this for the whole system and not only the class+block core, a few remainig places that use kobject_register() need to be changed to use kobject_add(), but that is a trivial change and nice too, cause it cleans up some error pathes, where a device needs to be unregistered in the same function and it emits two completely useless events for that. > And if we add this, can we pretty much get rid of all of the > wait_for_sysfs like logic in udev? Yes, that was the motivation to do this. With all the hotplug env vars we have now, we can throw out all the compiled-in lists and if some crazy devices still need to wait, we can add something to udev's rule logic, that a configured rule will wait for that file to show up. Thanks, Kay - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
