From 51c1d80e929bace26d2d795bd77fcc14b02ba3bb Mon Sep 17 00:00:00 2001 From: Stefan Richter Date: Mon, 12 Dec 2005 23:03:19 -0500 Subject: [PATCH] ieee1394: run high-level updates before high-level probes 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 Signed-off-by: Jody McIntyre --- drivers/ieee1394/nodemgr.c | 20 +++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-) diff --git a/drivers/ieee1394/nodemgr.c b/drivers/ieee1394/nodemgr.c index 01ab2bfa8d9d..0ec298768621 100644 --- a/drivers/ieee1394/nodemgr.c +++ b/drivers/ieee1394/nodemgr.c @@ -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);