ARM: 7703/1: Disable preemption in broadcast_tlb*_a15_erratum()
Commit 93dc688 (ARM: 7684/1: errata: Workaround for Cortex-A15 erratum
798181 (TLBI/DSB operations)) introduces calls to smp_processor_id() and
smp_call_function_many() with preemption enabled. This patch disables
preemption and also optimises the smp_processor_id() call in
broadcast_tlb_mm_a15_erratum(). The broadcast_tlb_a15_erratum() function
is changed to use smp_call_function() which disables preemption.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Geoff Levand <geoff@infradead.org>
Reported-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/kernel/smp_tlb.c b/arch/arm/kernel/smp_tlb.c
index e82e1d2..9a52a07 100644
--- a/arch/arm/kernel/smp_tlb.c
+++ b/arch/arm/kernel/smp_tlb.c
@@ -98,21 +98,21 @@
return;
dummy_flush_tlb_a15_erratum();
- smp_call_function_many(cpu_online_mask, ipi_flush_tlb_a15_erratum,
- NULL, 1);
+ smp_call_function(ipi_flush_tlb_a15_erratum, NULL, 1);
}
static void broadcast_tlb_mm_a15_erratum(struct mm_struct *mm)
{
- int cpu;
+ int cpu, this_cpu;
cpumask_t mask = { CPU_BITS_NONE };
if (!erratum_a15_798181())
return;
dummy_flush_tlb_a15_erratum();
+ this_cpu = get_cpu();
for_each_online_cpu(cpu) {
- if (cpu == smp_processor_id())
+ if (cpu == this_cpu)
continue;
/*
* We only need to send an IPI if the other CPUs are running
@@ -127,6 +127,7 @@
cpumask_set_cpu(cpu, &mask);
}
smp_call_function_many(&mask, ipi_flush_tlb_a15_erratum, NULL, 1);
+ put_cpu();
}
void flush_tlb_all(void)