dm mpath: check if scsi_dh module already loaded before trying to load

510193a2 · Mike Snitzer <[email protected]> · 2012-05-12 01:43:21 +01:00

If the requested scsi_dh module is already loaded then skip
request_module().

Multipath table loads can hang in an unnecessary __request_module.

Reported-by: Ben Marzinski <[email protected]>
Cc: [email protected]
Signed-off-by: Mike Snitzer <[email protected]>
Signed-off-by: Alasdair G Kergon <[email protected]>

Commit: 510193a2d3d2e03ae53b95c0ae4f33cdff02cbf8
Parents: 7cab8bf1

Changes

1 files changed · +2 −2

File	Status	Add	Del	Content
drivers/md/dm-mpath.c	modified	+2	−2	View file

drivers/md/dm-mpath.c

View file

diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index 922a338..754f38f 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -718,8 +718,8 @@ static int parse_hw_handler(struct dm_arg_set *as, struct multipath *m)
 		return 0;
 
 	m->hw_handler_name = kstrdup(dm_shift_arg(as), GFP_KERNEL);
-	request_module("scsi_dh_%s", m->hw_handler_name);
-	if (scsi_dh_handler_exist(m->hw_handler_name) == 0) {
+	if (!try_then_request_module(scsi_dh_handler_exist(m->hw_handler_name),
+				     "scsi_dh_%s", m->hw_handler_name)) {
 		ti->error = "unknown hardware handler type";
 		ret = -EINVAL;
 		goto fail;