Merge branch 'x86-threadinfo-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[linux-2.6-microblaze.git] / arch / x86 / kernel / dumpstack_32.c

diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c
index f2a1770..5abd4cd 100644 (file)
--- a/arch/x86/kernel/dumpstack_32.c
+++ b/arch/x86/kernel/dumpstack_32.c
@@ -16,12 +16,35 @@
 
 #include <asm/stacktrace.h>
 
+static void *is_irq_stack(void *p, void *irq)
+{
+       if (p < irq || p >= (irq + THREAD_SIZE))
+               return NULL;
+       return irq + THREAD_SIZE;
+}
+
+
+static void *is_hardirq_stack(unsigned long *stack, int cpu)
+{
+       void *irq = per_cpu(hardirq_stack, cpu);
+
+       return is_irq_stack(stack, irq);
+}
+
+static void *is_softirq_stack(unsigned long *stack, int cpu)
+{
+       void *irq = per_cpu(softirq_stack, cpu);
+
+       return is_irq_stack(stack, irq);
+}
 
 void dump_trace(struct task_struct *task, struct pt_regs *regs,
                unsigned long *stack, unsigned long bp,
                const struct stacktrace_ops *ops, void *data)
 {
+       const unsigned cpu = get_cpu();
        int graph = 0;
+       u32 *prev_esp;
 
        if (!task)
                task = current;
@@ -30,7 +53,7 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs,
                unsigned long dummy;
 
                stack = &dummy;
-               if (task && task != current)
+               if (task != current)
                        stack = (unsigned long *)task->thread.sp;
        }
 
@@ -39,18 +62,31 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs,
 
        for (;;) {
                struct thread_info *context;
+               void *end_stack;
+
+               end_stack = is_hardirq_stack(stack, cpu);
+               if (!end_stack)
+                       end_stack = is_softirq_stack(stack, cpu);
 
-               context = (struct thread_info *)
-                       ((unsigned long)stack & (~(THREAD_SIZE - 1)));
-               bp = ops->walk_stack(context, stack, bp, ops, data, NULL, &graph);
+               context = task_thread_info(task);
+               bp = ops->walk_stack(context, stack, bp, ops, data,
+                                    end_stack, &graph);
 
-               stack = (unsigned long *)context->previous_esp;
+               /* Stop if not on irq stack */
+               if (!end_stack)
+                       break;
+
+               /* The previous esp is saved on the bottom of the stack */
+               prev_esp = (u32 *)(end_stack - THREAD_SIZE);
+               stack = (unsigned long *)*prev_esp;
                if (!stack)
                        break;
+
                if (ops->stack(data, "IRQ") < 0)
                        break;
                touch_nmi_watchdog();
        }
+       put_cpu();
 }
 EXPORT_SYMBOL(dump_trace);