sched: use show_regs() to improve __schedule_bug() output
A full register dump along with stack backtrace would make the
"scheduling while atomic" message more helpful. Use show_regs() instead
of dump_stack() for this. We already know we're atomic in here (that is
why this function was called) so show_regs()'s atomicity expectations
are guaranteed.
Also, modify the output of the "BUG: scheduling while atomic:" header a
bit to keep task->comm and task->pid together and preempt_count() after
them.
Signed-off-by: Satyam Sharma <satyam@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/sched.c b/kernel/sched.c
index af02a4d..d1e6663 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -66,6 +66,7 @@
#include <linux/pagemap.h>
#include <asm/tlb.h>
+#include <asm/irq_regs.h>
/*
* Scheduler clock - returns current time in nanosec units.
@@ -3507,12 +3508,19 @@
*/
static noinline void __schedule_bug(struct task_struct *prev)
{
- printk(KERN_ERR "BUG: scheduling while atomic: %s/0x%08x/%d\n",
- prev->comm, preempt_count(), task_pid_nr(prev));
+ struct pt_regs *regs = get_irq_regs();
+
+ printk(KERN_ERR "BUG: scheduling while atomic: %s/%d/0x%08x\n",
+ prev->comm, prev->pid, preempt_count());
+
debug_show_held_locks(prev);
if (irqs_disabled())
print_irqtrace_events(prev);
- dump_stack();
+
+ if (regs)
+ show_regs(regs);
+ else
+ dump_stack();
}
/*