linux-stable/arch/s390/kernel/stacktrace.c
Heiko Carstens d0208639db s390/dumpstack: restore reliable indicator for call traces
Before merging all different stack tracers the call traces printed had
an indicator if an entry can be considered reliable or not.
Unreliable entries were put in braces, reliable not. Currently all
lines contain these extra braces.

This patch restores the old behaviour by adding an extra "reliable"
parameter to the callback functions. Only show_trace makes currently
use of it.

Before:
[    0.804751] Call Trace:
[    0.804753] ([<000000000017d0e0>] try_to_wake_up+0x318/0x5e0)
[    0.804756] ([<0000000000161d64>] create_worker+0x174/0x1c0)

After:
[    0.804751] Call Trace:
[    0.804753] ([<000000000017d0e0>] try_to_wake_up+0x318/0x5e0)
[    0.804756]  [<0000000000161d64>] create_worker+0x174/0x1c0

Fixes: 758d39ebd3 ("s390/dumpstack: merge all four stack tracers")
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-10-17 14:44:30 +02:00

73 lines
1.8 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 int __save_address(void *data, unsigned long address, int nosched)
{
struct stack_trace *trace = data;
if (nosched && in_sched_functions(address))
return 0;
if (trace->skip > 0) {
trace->skip--;
return 0;
}
if (trace->nr_entries < trace->max_entries) {
trace->entries[trace->nr_entries++] = address;
return 0;
}
return 1;
}
static int save_address(void *data, unsigned long address, int reliable)
{
return __save_address(data, address, 0);
}
static int save_address_nosched(void *data, unsigned long address, int reliable)
{
return __save_address(data, address, 1);
}
void save_stack_trace(struct stack_trace *trace)
{
unsigned long sp;
sp = current_stack_pointer();
dump_trace(save_address, trace, NULL, sp);
if (trace->nr_entries < trace->max_entries)
trace->entries[trace->nr_entries++] = ULONG_MAX;
}
EXPORT_SYMBOL_GPL(save_stack_trace);
void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
{
unsigned long sp;
sp = tsk->thread.ksp;
if (tsk == current)
sp = current_stack_pointer();
dump_trace(save_address_nosched, trace, tsk, sp);
if (trace->nr_entries < trace->max_entries)
trace->entries[trace->nr_entries++] = ULONG_MAX;
}
EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
void save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace)
{
unsigned long sp;
sp = kernel_stack_pointer(regs);
dump_trace(save_address, trace, NULL, sp);
if (trace->nr_entries < trace->max_entries)
trace->entries[trace->nr_entries++] = ULONG_MAX;
}
EXPORT_SYMBOL_GPL(save_stack_trace_regs);