[patch 02/47] cio: Dump ccw device information in case of timeout.

From: Martin Schwidefsky
Date: Thu Dec 20 2007 - 10:23:04 EST


From: Sebastian Ott <sebott@xxxxxxxxxx>

Information about a ccw device will be dumped in
case of a ccw timeout. This can be enabled with
the kernel parameter ccw_timeout_log.

Signed-off-by: Sebastian Ott <sebott@xxxxxxxxxx>
Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
---

Documentation/kernel-parameters.txt | 3 ++
Documentation/s390/CommonIO | 5 +++
drivers/s390/cio/device_fsm.c | 50 ++++++++++++++++++++++++++++++++++++
3 files changed, 58 insertions(+)

Index: quilt-2.6/Documentation/kernel-parameters.txt
===================================================================
--- quilt-2.6.orig/Documentation/kernel-parameters.txt
+++ quilt-2.6/Documentation/kernel-parameters.txt
@@ -369,6 +369,9 @@ and is between 256 and 4096 characters.
configured. Potentially dangerous and should only be
used if you are entirely sure of the consequences.

+ ccw_timeout_log [S390]
+ See Documentation/s390/CommonIO for details.
+
checkreqprot [SELINUX] Set initial checkreqprot flag value.
Format: { "0" | "1" }
See security/selinux/Kconfig help text.
Index: quilt-2.6/Documentation/s390/CommonIO
===================================================================
--- quilt-2.6.orig/Documentation/s390/CommonIO
+++ quilt-2.6/Documentation/s390/CommonIO
@@ -4,6 +4,11 @@ S/390 common I/O-Layer - command line pa
Command line parameters
-----------------------

+* ccw_timeout_log
+
+ Enable logging of debug information in case of ccw device timeouts.
+
+
* cio_msg = yes | no

Determines whether information on found devices and sensed device
Index: quilt-2.6/drivers/s390/cio/device_fsm.c
===================================================================
--- quilt-2.6.orig/drivers/s390/cio/device_fsm.c
+++ quilt-2.6/drivers/s390/cio/device_fsm.c
@@ -25,6 +25,8 @@
#include "ioasm.h"
#include "chp.h"

+static int timeout_log_enabled;
+
int
device_is_online(struct subchannel *sch)
{
@@ -82,6 +84,52 @@ int device_trigger_verify(struct subchan
return 0;
}

+static int __init ccw_timeout_log_setup(char *unused)
+{
+ timeout_log_enabled = 1;
+ return 1;
+}
+
+__setup("ccw_timeout_log", ccw_timeout_log_setup);
+
+static void ccw_timeout_log(struct ccw_device *cdev)
+{
+ struct schib schib;
+ struct subchannel *sch;
+ int cc;
+
+ sch = to_subchannel(cdev->dev.parent);
+ cc = stsch(sch->schid, &schib);
+
+ printk(KERN_WARNING "cio: ccw device timeout occurred at %llx, "
+ "device information:\n", get_clock());
+ printk(KERN_WARNING "cio: orb:\n");
+ print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
+ &sch->orb, sizeof(sch->orb), 0);
+ printk(KERN_WARNING "cio: ccw device bus id: %s\n", cdev->dev.bus_id);
+ printk(KERN_WARNING "cio: subchannel bus id: %s\n", sch->dev.bus_id);
+ printk(KERN_WARNING "cio: subchannel lpm: %02x, opm: %02x, "
+ "vpm: %02x\n", sch->lpm, sch->opm, sch->vpm);
+
+ if ((void *)(addr_t)sch->orb.cpa == &sch->sense_ccw ||
+ (void *)(addr_t)sch->orb.cpa == cdev->private->iccws)
+ printk(KERN_WARNING "cio: last channel program (intern):\n");
+ else
+ printk(KERN_WARNING "cio: last channel program:\n");
+
+ print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
+ (void *)(addr_t)sch->orb.cpa, sizeof(struct ccw1), 0);
+ printk(KERN_WARNING "cio: ccw device state: %d\n",
+ cdev->private->state);
+ printk(KERN_WARNING "cio: store subchannel returned: cc=%d\n", cc);
+ printk(KERN_WARNING "cio: schib:\n");
+ print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
+ &schib, sizeof(schib), 0);
+ printk(KERN_WARNING "cio: ccw device flags:\n");
+ print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
+ &cdev->private->flags, sizeof(cdev->private->flags), 0);
+}
+
/*
* Timeout function. It just triggers a DEV_EVENT_TIMEOUT.
*/
@@ -92,6 +140,8 @@ ccw_device_timeout(unsigned long data)

cdev = (struct ccw_device *) data;
spin_lock_irq(cdev->ccwlock);
+ if (timeout_log_enabled)
+ ccw_timeout_log(cdev);
dev_fsm_event(cdev, DEV_EVENT_TIMEOUT);
spin_unlock_irq(cdev->ccwlock);
}

--
blue skies,
Martin.

"Reality continues to ruin my life." - Calvin.

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