From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Brownell Date: Tue, 08 Oct 2002 18:14:22 +0000 Subject: Re: /sbin/hotplug invocation for USB devices in 2.5.40 Message-Id: List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-hotplug@vger.kernel.org Patrick Mochel wrote: >>>Now I know this overloads the existing DEVICE usage for USB devices, but >>>I think we can determine what do properly (basically just test for >>>DEVFS, and if it's not set, then we are looking at the driverfs entry >>>for the device.) >> >>I'd rather see these changes: >> >> - This new parameter to every (!!) hotplug event gets renamed to >> KFS_DEVICE (assuming that's the new driverfs name). > > > What about DEVPATH, since that's what it is, right? Well, it's different from usb_device->devpath ... devpath is just one component of the KFS path. One that's repeated because of that requirement that names assigned by a bus be unique across the whole system, making it easier to automate that symlinking. :) It's not the only filesystem path used to access the device. Would using KFS_DEVICE really be a problem? >>By the way, what's the cost of a driverfs attribute on a 'struct device'? >>Each USB device now has over a dozen of them. > > > 32 bytes/attribute + size of the function. But, attributes are reused > across devices, so the total data cost is 32 x ~16 = 512. "Reused" meaning shared attributes like "name" and "power", I guess. USB devices have at least one interface, and each will have six attributes (including name+power). So 32 x ~24 = 768 bytes minimum, on top of other costs. These start to add up. - Dave ------------------------------------------------------- This sf.net email is sponsored by:ThinkGeek Welcome to geek heaven. http://thinkgeek.com/sf _______________________________________________ Linux-hotplug-devel mailing list http://linux-hotplug.sourceforge.net Linux-hotplug-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel