2007-05-21 19:21:57

by Chris Wright

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

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

From: Doug Chapman <[email protected]>

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 <[email protected]>
Cc: <[email protected]>
Cc: James Bottomley <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Chris Wright <[email protected]>
---
[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)),

--