From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kay Sievers Date: Tue, 23 Aug 2005 20:03:27 +0000 Subject: Re: udevsynthesize as a udevstart+coldplug replacement Message-Id: <20050823200327.GB30794@vrfy.org> List-Id: References: <20050823191542.GA29091@vrfy.org> In-Reply-To: <20050823191542.GA29091@vrfy.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To: linux-hotplug@vger.kernel.org On Tue, Aug 23, 2005 at 10:46:43PM +0300, Mika Penttil=C3=A4 wrote: > Kay Sievers wrote: >=20 > >Here is "udevsynthesize" a possible replacement for the udevstart/coldpl= ug > >combination we currently have. Usually very early in the boot process, it > >gets all available devices from sysfs and synthesizes the events these > >devices would have generated at creation time. > >The events are directly passed to the udevd daemom socket. udevd does al= l=20 > >the > >work and runs all the events asynchronously. udevsynthesize itself does > >not read any udev rule. > > > >It scans block and class devices to create the the device nodes for alre= ady > >available devices, which obsoletes the run of udevstart. > >After that, it scans for bus devices, which events may load modules or > >configure the device. If the bus type is known, the usual bus-specific > >values are added to the event environment. > > > >With the "rules-in-daemon" patch, the whole udevstart/coldplug handling > >(700 events) takes less than a second CPU time on a 1.7Ghz laptop. > > > >A typical boot script would do: > > prepare tmpfs on /dev > > create /dev/null > > start /sbin/udevd > > disable /proc/sys/kernel/hotplug (the input layer is still broken and=20 > > needs a kernel patch) > > run /sbin/udevsynthesize > What if udevd receives netlink messages and goes into "ignore unix=20 > socket" mode before/while synthesize? No such mode exists. :) Only events with a SEQNUM set will possibly be ignored if received from userspace after netlink activity is detected. Kay ------------------------------------------------------- SF.Net email is Sponsored by the Better Software Conference & EXPO September 19-22, 2005 * San Francisco, CA * Development Lifecycle Practices Agile & Plan-Driven Development * Managing Projects & Teams * Testing & QA Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf _______________________________________________ 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