From 76737ce17ab4c88f14e4452076610474108246d7 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Sun, 31 Jan 2016 17:06:16 +0100 Subject: [PATCH] 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 Tested-by: Peter Oberparleiter Signed-off-by: Martin Schwidefsky --- arch/s390/include/asm/processor.h | 8 ++++++++ arch/s390/kernel/dumpstack.c | 16 ++++++++-------- arch/s390/kernel/irq.c | 3 +-- arch/s390/kernel/stacktrace.c | 9 +++------ 4 files changed, 20 insertions(+), 16 deletions(-) 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 @@ unsigned long get_wchan(struct task_struct *p); /* 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 @@ static void show_trace(struct task_struct *task, unsigned long *stack) { 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 @@ static void show_trace(struct task_struct *task, unsigned long *stack) 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 @@ void do_softirq_own_stack(void) { 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 3872d14f..7dd8360 100644 --- a/arch/s390/kernel/stacktrace.c +++ b/arch/s390/kernel/stacktrace.c @@ -77,10 +77,9 @@ static void __save_stack_trace(struct stack_trace *trace, unsigned long sp) 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 @@ void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) 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); -- 2.7.4