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-rw-r--r--arch/s390/oprofile/backtrace.c77
1 files changed, 77 insertions, 0 deletions
diff --git a/arch/s390/oprofile/backtrace.c b/arch/s390/oprofile/backtrace.c
new file mode 100644
index 000000000..8a6811b2c
--- /dev/null
+++ b/arch/s390/oprofile/backtrace.c
@@ -0,0 +1,77 @@
+/*
+ * S390 Version
+ * Copyright IBM Corp. 2005
+ * Author(s): Andreas Krebbel <Andreas.Krebbel@de.ibm.com>
+ */
+
+#include <linux/oprofile.h>
+
+#include <asm/processor.h> /* for struct stack_frame */
+
+static unsigned long
+__show_trace(unsigned int *depth, unsigned long sp,
+ unsigned long low, unsigned long high)
+{
+ struct stack_frame *sf;
+ struct pt_regs *regs;
+
+ while (*depth) {
+ sp = sp & PSW_ADDR_INSN;
+ if (sp < low || sp > high - sizeof(*sf))
+ return sp;
+ sf = (struct stack_frame *) sp;
+ (*depth)--;
+ oprofile_add_trace(sf->gprs[8] & PSW_ADDR_INSN);
+
+ /* Follow the backchain. */
+ while (*depth) {
+ 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;
+ (*depth)--;
+ oprofile_add_trace(sf->gprs[8] & PSW_ADDR_INSN);
+
+ }
+
+ if (*depth == 0)
+ break;
+
+ /* 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;
+ (*depth)--;
+ oprofile_add_trace(sf->gprs[8] & PSW_ADDR_INSN);
+ low = sp;
+ sp = regs->gprs[15];
+ }
+ return sp;
+}
+
+void s390_backtrace(struct pt_regs * const regs, unsigned int depth)
+{
+ unsigned long head;
+ struct stack_frame* head_sf;
+
+ if (user_mode(regs))
+ return;
+
+ head = regs->gprs[15];
+ head_sf = (struct stack_frame*)head;
+
+ if (!head_sf->back_chain)
+ return;
+
+ head = head_sf->back_chain;
+
+ head = __show_trace(&depth, head, S390_lowcore.async_stack - ASYNC_SIZE,
+ S390_lowcore.async_stack);
+
+ __show_trace(&depth, head, S390_lowcore.thread_info,
+ S390_lowcore.thread_info + THREAD_SIZE);
+}