linux-stable/arch/s390/kernel/stacktrace.c
Heiko Carstens a53c8fab3f s390/comments: unify copyright messages and remove file names
Remove the file name from the comment at top of many files. In most
cases the file name was wrong anyway, so it's rather pointless.

Also unify the IBM copyright statement. We did have a lot of sightly
different statements and wanted to change them one after another
whenever a file gets touched. However that never happened. Instead
people start to take the old/"wrong" statements to use as a template
for new files.
So unify all of them in one go.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2012-07-20 11:15:04 +02:00

96 lines
2.4 KiB
C

/*
* Stack trace management functions
*
* Copyright IBM Corp. 2006
* Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
*/
#include <linux/sched.h>
#include <linux/stacktrace.h>
#include <linux/kallsyms.h>
#include <linux/module.h>
static unsigned long save_context_stack(struct stack_trace *trace,
unsigned long sp,
unsigned long low,
unsigned long high,
int savesched)
{
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 (!trace->skip)
trace->entries[trace->nr_entries++] = addr;
else
trace->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 (savesched || !in_sched_functions(addr)) {
if (!trace->skip)
trace->entries[trace->nr_entries++] = addr;
else
trace->skip--;
}
if (trace->nr_entries >= trace->max_entries)
return sp;
low = sp;
sp = regs->gprs[15];
}
}
void save_stack_trace(struct stack_trace *trace)
{
register unsigned long sp asm ("15");
unsigned long orig_sp, new_sp;
orig_sp = sp & PSW_ADDR_INSN;
new_sp = save_context_stack(trace, orig_sp,
S390_lowcore.panic_stack - PAGE_SIZE,
S390_lowcore.panic_stack, 1);
if (new_sp != orig_sp)
return;
new_sp = save_context_stack(trace, new_sp,
S390_lowcore.async_stack - ASYNC_SIZE,
S390_lowcore.async_stack, 1);
if (new_sp != orig_sp)
return;
save_context_stack(trace, new_sp,
S390_lowcore.thread_info,
S390_lowcore.thread_info + THREAD_SIZE, 1);
}
EXPORT_SYMBOL_GPL(save_stack_trace);
void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
{
unsigned long sp, low, high;
sp = tsk->thread.ksp & PSW_ADDR_INSN;
low = (unsigned long) task_stack_page(tsk);
high = (unsigned long) task_pt_regs(tsk);
save_context_stack(trace, sp, low, high, 0);
if (trace->nr_entries < trace->max_entries)
trace->entries[trace->nr_entries++] = ULONG_MAX;
}
EXPORT_SYMBOL_GPL(save_stack_trace_tsk);