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-rw-r--r--arch/s390/kernel/stacktrace.c90
1 files changed, 90 insertions, 0 deletions
diff --git a/arch/s390/kernel/stacktrace.c b/arch/s390/kernel/stacktrace.c
new file mode 100644
index 00000000000..de83f38288d
--- /dev/null
+++ b/arch/s390/kernel/stacktrace.c
@@ -0,0 +1,90 @@
+/*
+ * arch/s390/kernel/stacktrace.c
+ *
+ * Stack trace management functions
+ *
+ * Copyright (C) IBM Corp. 2006
+ * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
+ */
+
+#include <linux/sched.h>
+#include <linux/stacktrace.h>
+#include <linux/kallsyms.h>
+
+static inline unsigned long save_context_stack(struct stack_trace *trace,
+ unsigned int *skip,
+ unsigned long sp,
+ unsigned long low,
+ unsigned long high)
+{
+ struct stack_frame *sf;
+ struct pt_regs *regs;
+ unsigned long addr;
+
+ while(1) {
+ sp &= PSW_ADDR_INSN;
+ if (sp < low || sp > high)
+ return sp;
+ sf = (struct stack_frame *)sp;
+ while(1) {
+ addr = sf->gprs[8] & PSW_ADDR_INSN;
+ if (!(*skip))
+ trace->entries[trace->nr_entries++] = addr;
+ else
+ (*skip)--;
+ if (trace->nr_entries >= trace->max_entries)
+ return sp;
+ low = sp;
+ sp = sf->back_chain & PSW_ADDR_INSN;
+ if (!sp)
+ break;
+ if (sp <= low || sp > high - sizeof(*sf))
+ return sp;
+ sf = (struct stack_frame *)sp;
+ }
+ /* Zero backchain detected, check for interrupt frame. */
+ sp = (unsigned long)(sf + 1);
+ if (sp <= low || sp > high - sizeof(*regs))
+ return sp;
+ regs = (struct pt_regs *)sp;
+ addr = regs->psw.addr & PSW_ADDR_INSN;
+ if (!(*skip))
+ trace->entries[trace->nr_entries++] = addr;
+ else
+ (*skip)--;
+ if (trace->nr_entries >= trace->max_entries)
+ return sp;
+ low = sp;
+ sp = regs->gprs[15];
+ }
+}
+
+void save_stack_trace(struct stack_trace *trace,
+ struct task_struct *task, int all_contexts,
+ unsigned int skip)
+{
+ register unsigned long sp asm ("15");
+ unsigned long orig_sp;
+
+ sp &= PSW_ADDR_INSN;
+ orig_sp = sp;
+
+ sp = save_context_stack(trace, &skip, sp,
+ S390_lowcore.panic_stack - PAGE_SIZE,
+ S390_lowcore.panic_stack);
+ if ((sp != orig_sp) && !all_contexts)
+ return;
+ sp = save_context_stack(trace, &skip, sp,
+ S390_lowcore.async_stack - ASYNC_SIZE,
+ S390_lowcore.async_stack);
+ if ((sp != orig_sp) && !all_contexts)
+ return;
+ if (task)
+ save_context_stack(trace, &skip, sp,
+ (unsigned long) task_stack_page(task),
+ (unsigned long) task_stack_page(task) + THREAD_SIZE);
+ else
+ save_context_stack(trace, &skip, sp, S390_lowcore.thread_info,
+ S390_lowcore.thread_info + THREAD_SIZE);
+ return;
+}