projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 5bdc9b44 HC |
1 | /* |
| 2 | * arch/s390/kernel/stacktrace.c | |
| 3 | * | |
| 4 | * Stack trace management functions | |
| 5 | * | |
| 6 | * Copyright (C) IBM Corp. 2006 | |
| 7 | * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com> | |
| 8 | */ | |
| 9 | ||
| 10 | #include <linux/sched.h> | |
| 11 | #include <linux/stacktrace.h> | |
| 12 | #include <linux/kallsyms.h> | |
| 13 | ||
| 4d284cac HC |
14 | static unsigned long save_context_stack(struct stack_trace *trace, |
| 15 | unsigned int *skip, | |
| 16 | unsigned long sp, | |
| 17 | unsigned long low, | |
| 18 | unsigned long high) | |
| 5bdc9b44 HC |
19 | { |
| 20 | struct stack_frame *sf; | |
| 21 | struct pt_regs *regs; | |
| 22 | unsigned long addr; | |
| 23 | ||
| 24 | while(1) { | |
| 25 | sp &= PSW_ADDR_INSN; | |
| 26 | if (sp < low || sp > high) | |
| 27 | return sp; | |
| 28 | sf = (struct stack_frame *)sp; | |
| 29 | while(1) { | |
| 30 | addr = sf->gprs[8] & PSW_ADDR_INSN; | |
| 31 | if (!(*skip)) | |
| 32 | trace->entries[trace->nr_entries++] = addr; | |
| 33 | else | |
| 34 | (*skip)--; | |
| 35 | if (trace->nr_entries >= trace->max_entries) | |
| 36 | return sp; | |
| 37 | low = sp; | |
| 38 | sp = sf->back_chain & PSW_ADDR_INSN; | |
| 39 | if (!sp) | |
| 40 | break; | |
| 41 | if (sp <= low || sp > high - sizeof(*sf)) | |
| 42 | return sp; | |
| 43 | sf = (struct stack_frame *)sp; | |
| 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 | addr = regs->psw.addr & PSW_ADDR_INSN; | |
| 51 | if (!(*skip)) | |
| 52 | trace->entries[trace->nr_entries++] = addr; | |
| 53 | else | |
| 54 | (*skip)--; | |
| 55 | if (trace->nr_entries >= trace->max_entries) | |
| 56 | return sp; | |
| 57 | low = sp; | |
| 58 | sp = regs->gprs[15]; | |
| 59 | } | |
| 60 | } | |
| 61 | ||
| ab1b6f03 | 62 | void save_stack_trace(struct stack_trace *trace) |
| 5bdc9b44 HC |
63 | { |
| 64 | register unsigned long sp asm ("15"); | |
| 75e9de18 | 65 | unsigned long orig_sp, new_sp; |
| 5bdc9b44 | 66 | |
| 75e9de18 | 67 | orig_sp = sp & PSW_ADDR_INSN; |
| 5bdc9b44 | 68 | |
| 75e9de18 | 69 | new_sp = save_context_stack(trace, &trace->skip, orig_sp, |
| 5bdc9b44 HC |
70 | S390_lowcore.panic_stack - PAGE_SIZE, |
| 71 | S390_lowcore.panic_stack); | |
| ab1b6f03 | 72 | if (new_sp != orig_sp) |
| 5bdc9b44 | 73 | return; |
| 75e9de18 | 74 | new_sp = save_context_stack(trace, &trace->skip, new_sp, |
| 5bdc9b44 HC |
75 | S390_lowcore.async_stack - ASYNC_SIZE, |
| 76 | S390_lowcore.async_stack); | |
| ab1b6f03 | 77 | if (new_sp != orig_sp) |
| 5bdc9b44 | 78 | return; |
| ab1b6f03 CH |
79 | |
| 80 | save_context_stack(trace, &trace->skip, new_sp, | |
| 81 | S390_lowcore.thread_info, | |
| 82 | S390_lowcore.thread_info + THREAD_SIZE); | |
| 5bdc9b44 HC |
83 | return; |
| 84 | } |