Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/csky/kernel/dumpstack.c b/arch/csky/kernel/dumpstack.c
new file mode 100644
index 0000000..d67f977
--- /dev/null
+++ b/arch/csky/kernel/dumpstack.c
@@ -0,0 +1,49 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/ptrace.h>
+
+int kstack_depth_to_print = 48;
+
+void show_trace(unsigned long *stack)
+{
+ unsigned long *stack_end;
+ unsigned long *stack_start;
+ unsigned long *fp;
+ unsigned long addr;
+
+ addr = (unsigned long) stack & THREAD_MASK;
+ stack_start = (unsigned long *) addr;
+ stack_end = (unsigned long *) (addr + THREAD_SIZE);
+
+ fp = stack;
+ pr_info("\nCall Trace:");
+
+ while (fp > stack_start && fp < stack_end) {
+#ifdef CONFIG_STACKTRACE
+ addr = fp[1];
+ fp = (unsigned long *) fp[0];
+#else
+ addr = *fp++;
+#endif
+ if (__kernel_text_address(addr))
+ pr_cont("\n[<%08lx>] %pS", addr, (void *)addr);
+ }
+ pr_cont("\n");
+}
+
+void show_stack(struct task_struct *task, unsigned long *stack)
+{
+ if (!stack) {
+ if (task)
+ stack = (unsigned long *)thread_saved_fp(task);
+ else
+#ifdef CONFIG_STACKTRACE
+ asm volatile("mov %0, r8\n":"=r"(stack)::"memory");
+#else
+ stack = (unsigned long *)&stack;
+#endif
+ }
+
+ show_trace(stack);
+}