[patch 42/69] fix for bugzilla 8426: massive slowdown on SCSI CD/DVD drive connected to mptspi driver

[Chris Wright]

-stable review patch.  If anyone has any objections, please let us know.
---------------------

From: Doug Chapman <doug.chapman@xxxxxx>

Patch for: http://bugzilla.kernel.org/show_bug.cgi?id=8426

A recent code cleanup that moved code from mptscsih to mptspi inadvertently
change the order some code was called.  This caused a massive slowdown (of
150x to 300x) on the CD/DVD drive on the high-end HP Integrity servers.

Signed-off-by: Doug Chapman <doug.chapman@xxxxxx>
Cc: <Eric.Moore@xxxxxxxx>
Cc: James Bottomley <James.Bottomley@xxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Chris Wright <chrisw@xxxxxxxxxxxx>
---
[chrisw: Why is this not upstream yet?]

 drivers/message/fusion/mptspi.c |    8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

--- linux-2.6.21.1.orig/drivers/message/fusion/mptspi.c
+++ linux-2.6.21.1/drivers/message/fusion/mptspi.c
@@ -726,13 +726,15 @@ static int mptspi_slave_configure(struct
 	struct _MPT_SCSI_HOST *hd =
 		(struct _MPT_SCSI_HOST *)sdev->host->hostdata;
 	VirtTarget *vtarget = scsi_target(sdev)->hostdata;
-	int ret = mptscsih_slave_configure(sdev);
+	int ret;
+
+	mptspi_initTarget(hd, vtarget, sdev);
+
+	ret = mptscsih_slave_configure(sdev);
 
 	if (ret)
 		return ret;
 
-	mptspi_initTarget(hd, vtarget, sdev);
-
 	ddvprintk((MYIOC_s_INFO_FMT "id=%d min_period=0x%02x"
 		" max_offset=0x%02x max_width=%d\n", hd->ioc->name,
 		sdev->id, spi_min_period(scsi_target(sdev)),

-- 
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