From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tristan Wibberley Date: Tue, 13 Jan 2004 19:05:26 +0000 Subject: Re: about split the udev Message-Id: List-Id: References: <3ACA40606221794F80A5670F0AF15F8402D4EE96@PDSMSX403.ccr.corp.intel.com> In-Reply-To: <3ACA40606221794F80A5670F0AF15F8402D4EE96@PDSMSX403.ccr.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-hotplug@vger.kernel.org -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Greg KH wrote: | I am talking about udev splitting into 2 pieces: | udev - called the same way udev is called today. | creates a tiny message queue message based on the hotplug | event and then exits. This can probably be done in under | 6Kb of binary code. | udevd - receives the udev message queue messages. Orders them | in the proper order (based on the SEQ_NUM from the | hotplug event), and then acts on them. Size should be | about what we have today for the udev binary 50Kb or so. | | We need to do this in order to properly handle out of order hotplug | events. Will that solve the problem? If udevd keeps up with the messages, and the udev that supplies the second message pre-empts the one that provides the first, will udevd process the second message because it doesn't know that there is an earlier one about to come in? If udevd waits for contiguous SEQ_NUMs to ensure this doesn't happen, then a dead/locked-up udev will freeze everything (udevd won't know which of the events it has should wait until after the unknown one). I think a different solution is required. Just what, I don't know - I'm quite new here :) I'm probably way off anyway. - -- Tristan Wibberley -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.4 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://enigmail.mozdev.org iD4DBQFABEF18z3lIaW+LfIRAgKdAKDOg2XGNq7SeAEO9nc0IZednOXXjACVGMsb 4DdwePXa6NP9AvgQ3OadmA= =u3ca -----END PGP SIGNATURE----- ------------------------------------------------------- This SF.net email is sponsored by: Perforce Software. Perforce is the Fast Software Configuration Management System offering advanced branching capabilities and atomic changes on 50+ platforms. Free Eval! http://www.perforce.com/perforce/loadprog.html _______________________________________________ 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