s390: add current_stack_pointer() helper function
Implement current_stack_pointer() helper function and use it
everywhere, instead of having several different inline assembly
variants.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Tested-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h
index 1c4fe12..073e18b 100644
--- a/arch/s390/include/asm/processor.h
+++ b/arch/s390/include/asm/processor.h
@@ -203,6 +203,14 @@
/* Has task runtime instrumentation enabled ? */
#define is_ri_task(tsk) (!!(tsk)->thread.ri_cb)
+static inline unsigned long current_stack_pointer(void)
+{
+ unsigned long sp;
+
+ asm volatile("la %0,0(15)" : "=a" (sp));
+ return sp;
+}
+
static inline unsigned short stap(void)
{
unsigned short cpu_address;
diff --git a/arch/s390/kernel/dumpstack.c b/arch/s390/kernel/dumpstack.c
index 02bd02f..feda48f 100644
--- a/arch/s390/kernel/dumpstack.c
+++ b/arch/s390/kernel/dumpstack.c
@@ -67,12 +67,11 @@
{
const unsigned long frame_size =
STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
- register unsigned long __r15 asm ("15");
unsigned long sp;
sp = (unsigned long) stack;
if (!sp)
- sp = task ? task->thread.ksp : __r15;
+ sp = task ? task->thread.ksp : current_stack_pointer();
printk("Call Trace:\n");
#ifdef CONFIG_CHECK_STACK
sp = __show_trace(sp,
@@ -95,15 +94,16 @@
void show_stack(struct task_struct *task, unsigned long *sp)
{
- register unsigned long *__r15 asm ("15");
unsigned long *stack;
int i;
- if (!sp)
- stack = task ? (unsigned long *) task->thread.ksp : __r15;
- else
- stack = sp;
-
+ stack = sp;
+ if (!stack) {
+ if (!task)
+ stack = (unsigned long *)current_stack_pointer();
+ else
+ stack = (unsigned long *)task->thread.ksp;
+ }
for (i = 0; i < 20; i++) {
if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
break;
diff --git a/arch/s390/kernel/irq.c b/arch/s390/kernel/irq.c
index f41d520..c373a1d 100644
--- a/arch/s390/kernel/irq.c
+++ b/arch/s390/kernel/irq.c
@@ -164,8 +164,7 @@
{
unsigned long old, new;
- /* Get current stack pointer. */
- asm volatile("la %0,0(15)" : "=a" (old));
+ old = current_stack_pointer();
/* Check against async. stack address range. */
new = S390_lowcore.async_stack;
if (((new - old) >> (PAGE_SHIFT + THREAD_ORDER)) != 0) {
diff --git a/arch/s390/kernel/stacktrace.c b/arch/s390/kernel/stacktrace.c
index 3872d14..7dd8360 100644
--- a/arch/s390/kernel/stacktrace.c
+++ b/arch/s390/kernel/stacktrace.c
@@ -77,10 +77,9 @@
void save_stack_trace(struct stack_trace *trace)
{
- register unsigned long r15 asm ("15");
unsigned long sp;
- sp = r15;
+ sp = current_stack_pointer();
__save_stack_trace(trace, sp);
if (trace->nr_entries < trace->max_entries)
trace->entries[trace->nr_entries++] = ULONG_MAX;
@@ -92,10 +91,8 @@
unsigned long sp, low, high;
sp = tsk->thread.ksp;
- if (tsk == current) {
- /* Get current stack pointer. */
- asm volatile("la %0,0(15)" : "=a" (sp));
- }
+ if (tsk == current)
+ sp = current_stack_pointer();
low = (unsigned long) task_stack_page(tsk);
high = (unsigned long) task_pt_regs(tsk);
save_context_stack(trace, sp, low, high, 1);