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