From ec61b9b5a68947bf1078ccb2b3523f14af573ded Mon Sep 17 00:00:00 2001
From: Daniel Gnoutcheff <gnoutchd@dan-lap.(none)>
Date: Wed, 17 Dec 2008 13:09:21 -0500
Subject: [PATCH] Experiment with forcing a panic to get a crashdump of schedule_timeout.

---
 drivers/ata/ahci.c         |    3 +++
 include/ahci-force-panic.h |    2 ++
 kernel/timer.c             |    8 ++++++++
 3 files changed, 13 insertions(+), 0 deletions(-)
 create mode 100644 include/ahci-force-panic.h

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index a67b8e7..1af5e3e 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -45,6 +45,7 @@
 #include <scsi/scsi_host.h>
 #include <scsi/scsi_cmnd.h>
 #include <linux/libata.h>
+#include <ahci-force-panic.h>
 
 #define DRV_NAME	"ahci"
 #define DRV_VERSION	"3.0"
@@ -2311,6 +2312,8 @@ static int ahci_pci_device_resume(struct pci_dev *pdev)
 	struct ata_host *host = dev_get_drvdata(&pdev->dev);
 	int rc;
 
+	schedule_timeout_force_panic = 1;
+
 	rc = ata_pci_device_do_resume(pdev);
 	if (rc)
 		return rc;
diff --git a/include/ahci-force-panic.h b/include/ahci-force-panic.h
new file mode 100644
index 0000000..85cce42
--- /dev/null
+++ b/include/ahci-force-panic.h
@@ -0,0 +1,2 @@
+extern int schedule_timeout_force_panic;
+
diff --git a/kernel/timer.c b/kernel/timer.c
index dbd50fa..c239a60 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -19,6 +19,7 @@
  *              Designed by David S. Miller, Alexey Kuznetsov and Ingo Molnar
  */
 
+#include <linux/kernel.h>
 #include <linux/kernel_stat.h>
 #include <linux/module.h>
 #include <linux/interrupt.h>
@@ -44,6 +45,10 @@
 #include <asm/timex.h>
 #include <asm/io.h>
 
+#include <ahci-force-panic.h>
+int schedule_timeout_force_panic = 0;
+EXPORT_SYMBOL(schedule_timeout_force_panic); 
+
 u64 jiffies_64 __cacheline_aligned_in_smp = INITIAL_JIFFIES;
 
 EXPORT_SYMBOL(jiffies_64);
@@ -1284,6 +1289,9 @@ signed long __sched schedule_timeout(signed long timeout)
 
 	setup_timer_on_stack(&timer, process_timeout, (unsigned long)current);
 	__mod_timer(&timer, expire);
+	if (schedule_timeout_force_panic) {
+		panic("schedule_timeout: panic forced.");
+	}
 	schedule();
 	del_singleshot_timer_sync(&timer);
 
-- 
1.5.6.3