1 files changed, 85 insertions, 0 deletions

diff --git a/arch/mips/kernel/stacktrace.c b/arch/mips/kernel/stacktrace.c
new file mode 100644
index 000000000000..4aabe526a68e
--- /dev/null
+++ b/arch/mips/kernel/stacktrace.c
@@ -0,0 +1,85 @@
+/*
+ * arch/mips/kernel/stacktrace.c
+ *
+ * Stack trace management functions
+ *
+ *  Copyright (C) 2006 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
+ */
+#include <linux/sched.h>
+#include <linux/stacktrace.h>
+#include <asm/stacktrace.h>
+
+/*
+ * Save stack-backtrace addresses into a stack_trace buffer:
+ */
+static void save_raw_context_stack(struct stack_trace *trace,
+        unsigned long reg29)
+{
+        unsigned long *sp = (unsigned long *)reg29;
+        unsigned long addr;
+
+        while (!kstack_end(sp)) {
+                addr = *sp++;
+                if (__kernel_text_address(addr)) {
+                        if (trace->skip > 0)
+                                trace->skip--;
+                        else
+                                trace->entries[trace->nr_entries++] = addr;
+                        if (trace->nr_entries >= trace->max_entries)
+                                break;
+                }
+        }
+}
+
+static void save_context_stack(struct stack_trace *trace,
+        struct task_struct *task, struct pt_regs *regs)
+{
+        unsigned long sp = regs->regs[29];
+#ifdef CONFIG_KALLSYMS
+        unsigned long ra = regs->regs[31];
+        unsigned long pc = regs->cp0_epc;
+
+        if (raw_show_trace || !__kernel_text_address(pc)) {
+                unsigned long stack_page =
+                        (unsigned long)task_stack_page(task);
+                if (stack_page && sp >= stack_page &&
+                    sp <= stack_page + THREAD_SIZE - 32)
+                        save_raw_context_stack(trace, sp);
+                return;
+        }
+        do {
+                if (trace->skip > 0)
+                        trace->skip--;
+                else
+                        trace->entries[trace->nr_entries++] = pc;
+                if (trace->nr_entries >= trace->max_entries)
+                        break;
+                pc = unwind_stack(task, &sp, pc, &ra);
+        } while (pc);
+#else
+        save_raw_context_stack(sp);
+#endif
+}
+
+/*
+ * Save stack-backtrace addresses into a stack_trace buffer.
+ */
+void save_stack_trace(struct stack_trace *trace, struct task_struct *task)
+{
+        struct pt_regs dummyregs;
+        struct pt_regs *regs = &dummyregs;
+
+        WARN_ON(trace->nr_entries || !trace->max_entries);
+
+        if (task && task != current) {
+                regs->regs[29] = task->thread.reg29;
+                regs->regs[31] = 0;
+                regs->cp0_epc = task->thread.reg31;
+        } else {
+                if (!task)
+                        task = current;
+                prepare_frametrace(regs);
+        }
+
+        save_context_stack(trace, task, regs);
+}