1 /**
2 * arch/s390/oprofile/backtrace.c
3 *
4 * S390 Version
5 * Copyright (C) 2005 IBM Corporation, IBM Deutschland Entwicklung GmbH.
6 * Author(s): Andreas Krebbel <Andreas.Krebbel@de.ibm.com>
7 */
8
9 #include <linux/oprofile.h>
10
11 #include <asm/processor.h> /* for struct stack_frame */
12
13 static unsigned long
__show_trace(unsigned int * depth,unsigned long sp,unsigned long low,unsigned long high)14 __show_trace(unsigned int *depth, unsigned long sp,
15 unsigned long low, unsigned long high)
16 {
17 struct stack_frame *sf;
18 struct pt_regs *regs;
19
20 while (*depth) {
21 sp = sp & PSW_ADDR_INSN;
22 if (sp < low || sp > high - sizeof(*sf))
23 return sp;
24 sf = (struct stack_frame *) sp;
25 (*depth)--;
26 oprofile_add_trace(sf->gprs[8] & PSW_ADDR_INSN);
27
28 /* Follow the backchain. */
29 while (*depth) {
30 low = sp;
31 sp = sf->back_chain & PSW_ADDR_INSN;
32 if (!sp)
33 break;
34 if (sp <= low || sp > high - sizeof(*sf))
35 return sp;
36 sf = (struct stack_frame *) sp;
37 (*depth)--;
38 oprofile_add_trace(sf->gprs[8] & PSW_ADDR_INSN);
39
40 }
41
42 if (*depth == 0)
43 break;
44
45 /* Zero backchain detected, check for interrupt frame. */
46 sp = (unsigned long) (sf + 1);
47 if (sp <= low || sp > high - sizeof(*regs))
48 return sp;
49 regs = (struct pt_regs *) sp;
50 (*depth)--;
51 oprofile_add_trace(sf->gprs[8] & PSW_ADDR_INSN);
52 low = sp;
53 sp = regs->gprs[15];
54 }
55 return sp;
56 }
57
s390_backtrace(struct pt_regs * const regs,unsigned int depth)58 void s390_backtrace(struct pt_regs * const regs, unsigned int depth)
59 {
60 unsigned long head;
61 struct stack_frame* head_sf;
62
63 if (user_mode (regs))
64 return;
65
66 head = regs->gprs[15];
67 head_sf = (struct stack_frame*)head;
68
69 if (!head_sf->back_chain)
70 return;
71
72 head = head_sf->back_chain;
73
74 head = __show_trace(&depth, head, S390_lowcore.async_stack - ASYNC_SIZE,
75 S390_lowcore.async_stack);
76
77 __show_trace(&depth, head, S390_lowcore.thread_info,
78 S390_lowcore.thread_info + THREAD_SIZE);
79 }
80