[PATCH 07/11] blackfin: smp: fix msg queue overflow issue

From: Bob Liu
Date: Sun Dec 11 2011 - 22:30:38 EST


From: Steven Miao <realmz6@xxxxxxxxx>

disable preemption when icache flush and use wait mode cross call, hold the msg
queue lock while handle cross function call to avoid overflow

Signed-off-by: Steven Miao <realmz6@xxxxxxxxx>
Signed-off-by: Bob Liu <lliubbo@xxxxxxxxx>
---
arch/blackfin/mach-common/smp.c | 8 +++-----
1 files changed, 3 insertions(+), 5 deletions(-)

diff --git a/arch/blackfin/mach-common/smp.c b/arch/blackfin/mach-common/smp.c
index d346405..ac8f8a4 100644
--- a/arch/blackfin/mach-common/smp.c
+++ b/arch/blackfin/mach-common/smp.c
@@ -193,14 +193,10 @@ static irqreturn_t ipi_handler_int1(int irq, void *dev_instance)
scheduler_ipi();
break;
case BFIN_IPI_CALL_FUNC:
- spin_unlock_irqrestore(&msg_queue->lock, flags);
ipi_call_function(cpu, msg);
- spin_lock_irqsave(&msg_queue->lock, flags);
break;
case BFIN_IPI_CPU_STOP:
- spin_unlock_irqrestore(&msg_queue->lock, flags);
ipi_cpu_stop(cpu);
- spin_lock_irqsave(&msg_queue->lock, flags);
break;
default:
printk(KERN_CRIT "CPU%u: Unknown IPI message 0x%lx\n",
@@ -482,8 +478,10 @@ void smp_icache_flush_range_others(unsigned long start, unsigned long end)
smp_flush_data.start = start;
smp_flush_data.end = end;

- if (smp_call_function(&ipi_flush_icache, &smp_flush_data, 0))
+ preempt_disable();
+ if (smp_call_function(&ipi_flush_icache, &smp_flush_data, 1))
printk(KERN_WARNING "SMP: failed to run I-cache flush request on other CPUs\n");
+ preempt_enable();
}
EXPORT_SYMBOL_GPL(smp_icache_flush_range_others);

--
1.7.0.4


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