ieee1394: run high-level updates before high-level probes (51c1d80e) · Commits · 戴 / test

After a bus reset, let nodemgr call high-level update hooks first for nodes which do not need to be probed. The main benefit is for a bus with more than one SBP-2 device: SBP-2 reconnects will be performed before SBP-2 logins, thus have a much higher chance to succeed, and their SCSI devices will not be blocked much longer than necessary. This was demonstrated for Linux 2.4 by Dave Cinege a while ago. A better approach would be to perform time-consuming probes in parallel by a subthread. I actually plan to implement this for sbp2 but it may take a while to get that done and tested. Until then, this tweak is a huge improvement for users with multiple SBP-2 devices. Signed-off-by:

Stefan Richter <stefanr@s5r6.in-berlin.de> Signed-off-by:

Jody McIntyre <scjody@modernduck.com>

drivers/ieee1394/nodemgr.c

+17 −3

Original line number	Diff line number	Diff line
		@@ -1407,14 +1407,28 @@ static void nodemgr_node_probe(struct host_info *hi, int generation)
		struct hpsb_host *host = hi->host;
		struct class *class = &nodemgr_ne_class;
		struct class_device *cdev;
		struct node_entry *ne;

		/* Do some processing of the nodes we've probed. This pulls them
		* into the sysfs layer if needed, and can result in processing of
		* unit-directories, or just updating the node and it's
		* unit-directories. */
		* unit-directories.
		*
		* Run updates before probes. Usually, updates are time-critical
		* while probes are time-consuming. (Well, those probes need some
		* improvement...) */

		down_read(&class->subsys.rwsem);
		list_for_each_entry(cdev, &class->children, node)
		nodemgr_probe_ne(hi, container_of(cdev, struct node_entry, class_dev), generation);
		list_for_each_entry(cdev, &class->children, node) {
		ne = container_of(cdev, struct node_entry, class_dev);
		if (!ne->needs_probe)
		nodemgr_probe_ne(hi, ne, generation);
		}
		list_for_each_entry(cdev, &class->children, node) {
		ne = container_of(cdev, struct node_entry, class_dev);
		if (ne->needs_probe)
		nodemgr_probe_ne(hi, ne, generation);
		}
		up_read(&class->subsys.rwsem);

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