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[S390] smp: disable preemption in smp_call_function/smp_call_function_on

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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>
This commit is contained in:
Heiko Carstens
2007-03-05 23:35:41 +01:00
committed by Martin Schwidefsky
parent f794c8279d
commit 25864162c1
1 changed files with 8 additions and 7 deletions
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15
arch/s390/kernel/smp.c
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@@ -94,10 +94,9 @@ static void __smp_call_function_map(void (*func) (void *info), void *info,
int cpu, local = 0; int cpu, local = 0;
/* /*
* Can deadlock when interrupts are disabled or if in wrong context, * Can deadlock when interrupts are disabled or if in wrong context.
* caller must disable preemption
*/ */
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 * Check for local function call. We have to have the same call order
@@ -152,17 +151,18 @@ out:
* Run a function on all other CPUs. * Run a function on all other CPUs.
* *
* You must not call this function with disabled interrupts or from a * You must not call this function with disabled interrupts or from a
* hardware interrupt handler. Must be called with preemption disabled. * hardware interrupt handler. You may call it from a bottom half.
* You may call it from a bottom half.
*/ */
int smp_call_function(void (*func) (void *info), void *info, int nonatomic, int smp_call_function(void (*func) (void *info), void *info, int nonatomic,
int wait) int wait)
{ {
cpumask_t map; cpumask_t map;
preempt_disable();
map = cpu_online_map; map = cpu_online_map;
cpu_clear(smp_processor_id(), map); cpu_clear(smp_processor_id(), map);
__smp_call_function_map(func, info, nonatomic, wait, map); __smp_call_function_map(func, info, nonatomic, wait, map);
preempt_enable();
return 0; return 0;
} }
EXPORT_SYMBOL(smp_call_function); EXPORT_SYMBOL(smp_call_function);
@@ -178,16 +178,17 @@ EXPORT_SYMBOL(smp_call_function);
* Run a function on one processor. * Run a function on one processor.
* *
* You must not call this function with disabled interrupts or from a * You must not call this function with disabled interrupts or from a
* hardware interrupt handler. Must be called with preemption disabled. * hardware interrupt handler. You may call it from a bottom half.
* You may call it from a bottom half.
*/ */
int smp_call_function_on(void (*func) (void *info), void *info, int nonatomic, int smp_call_function_on(void (*func) (void *info), void *info, int nonatomic,
int wait, int cpu) int wait, int cpu)
{ {
cpumask_t map = CPU_MASK_NONE; cpumask_t map = CPU_MASK_NONE;
preempt_disable();
cpu_set(cpu, map); cpu_set(cpu, map);
__smp_call_function_map(func, info, nonatomic, wait, map); __smp_call_function_map(func, info, nonatomic, wait, map);
preempt_enable();
return 0; return 0;
} }
EXPORT_SYMBOL(smp_call_function_on); EXPORT_SYMBOL(smp_call_function_on);