[S390] smp: disable preemption in smp_call_function/smp_call_function_on
Avoid sprinkling a _lot_ of preempt_disable/preempt_enable pairs.
This would be necessary for e.g. the iucv driver. Also this way we
are more consistent with other architectures which disable
preemption at least for smp_call_function.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index ecaa432..97764f7 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -94,10 +94,9 @@
int cpu, local = 0;
/*
- * Can deadlock when interrupts are disabled or if in wrong context,
- * caller must disable preemption
+ * Can deadlock when interrupts are disabled or if in wrong context.
*/
- WARN_ON(irqs_disabled() || in_irq() || preemptible());
+ WARN_ON(irqs_disabled() || in_irq());
/*
* Check for local function call. We have to have the same call order
@@ -152,17 +151,18 @@
* Run a function on all other CPUs.
*
* You must not call this function with disabled interrupts or from a
- * hardware interrupt handler. Must be called with preemption disabled.
- * You may call it from a bottom half.
+ * hardware interrupt handler. You may call it from a bottom half.
*/
int smp_call_function(void (*func) (void *info), void *info, int nonatomic,
int wait)
{
cpumask_t map;
+ preempt_disable();
map = cpu_online_map;
cpu_clear(smp_processor_id(), map);
__smp_call_function_map(func, info, nonatomic, wait, map);
+ preempt_enable();
return 0;
}
EXPORT_SYMBOL(smp_call_function);
@@ -178,16 +178,17 @@
* Run a function on one processor.
*
* You must not call this function with disabled interrupts or from a
- * hardware interrupt handler. Must be called with preemption disabled.
- * You may call it from a bottom half.
+ * hardware interrupt handler. You may call it from a bottom half.
*/
int smp_call_function_on(void (*func) (void *info), void *info, int nonatomic,
int wait, int cpu)
{
cpumask_t map = CPU_MASK_NONE;
+ preempt_disable();
cpu_set(cpu, map);
__smp_call_function_map(func, info, nonatomic, wait, map);
+ preempt_enable();
return 0;
}
EXPORT_SYMBOL(smp_call_function_on);