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[S390] smp_call_function/smp_call_function_on locking.

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smp_call_function and smp_call_function_on share the same lock and
smp_call_function_on disables softirq's so it can be called from
softirq context as well. Hence smp_call_function muss disable
softirqs as well to avoid deadlocks.

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 2007-02-12 15:47:04 +01:00 committed by Martin Schwidefsky
parent 509cb37e17
commit 0ec67667ab
1 changed files with 9 additions and 6 deletions
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15
arch/s390/kernel/smp.c
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@ -57,7 +57,7 @@ static void smp_ext_bitcall(int, ec_bit_sig);
static void smp_ext_bitcall_others(ec_bit_sig);
/*
5B * Structure and data for smp_call_function(). This is designed to minimise
* Structure and data for smp_call_function(). This is designed to minimise
* static memory requirements. It also looks cleaner.
*/
static DEFINE_SPINLOCK(call_lock);
@ -104,7 +104,7 @@ int smp_call_function (void (*func) (void *info), void *info, int nonatomic,
* remote CPUs are nearly ready to execute <<func>> or are or have executed.
*
* You must not call this function with disabled interrupts or from a
* hardware interrupt handler or from a bottom half handler.
* hardware interrupt handler.
*/
{
struct call_data_struct data;
@ -113,8 +113,8 @@ int smp_call_function (void (*func) (void *info), void *info, int nonatomic,
if (cpus <= 0)
return 0;
/* Can deadlock when called with interrupts disabled */
WARN_ON(irqs_disabled());
/* Can deadlock when interrupts are disabled or if in wrong context */
WARN_ON(irqs_disabled() || in_irq());
data.func = func;
data.info = info;
@ -123,7 +123,7 @@ int smp_call_function (void (*func) (void *info), void *info, int nonatomic,
if (wait)
atomic_set(&data.finished, 0);
spin_lock(&call_lock);
spin_lock_bh(&call_lock);
call_data = &data;
/* Send a message to all other CPUs and wait for them to respond */
smp_ext_bitcall_others(ec_call_function);
@ -135,7 +135,7 @@ int smp_call_function (void (*func) (void *info), void *info, int nonatomic,
if (wait)
while (atomic_read(&data.finished) != cpus)
cpu_relax();
spin_unlock(&call_lock);
spin_unlock_bh(&call_lock);
return 0;
}
@ -159,6 +159,9 @@ int smp_call_function_on(void (*func) (void *info), void *info,
if (!cpu_online(cpu))
return -EINVAL;
/* Can deadlock when interrupts are disabled or if in wrong context */
WARN_ON(irqs_disabled() || in_irq());
/* disable preemption for local function call */
curr_cpu = get_cpu();