From: Yong Zhang <yong.zhang@xxxxxxxxxxxxx> 1) call_function.lock used in smp_call_function_many() is just to protect call_function.queue and &data->refs, cpu_online_mask is outside of the lock. And it's not necessary to protect cpu_online_mask, because data->cpumask is pre-calculate and even if a cpu is brougt up when calling arch_send_call_function_ipi_mask(), it's harmless because validation test in generic_smp_call_function_interrupt() will take care of it. 2) For cpu down issue, stop_machine() will guarantee that no concurrent smp_call_fuction() is processing. Signed-off-by: Yong Zhang <yong.zhang0@xxxxxxxxx> Cc: Tony Luck <tony.luck@xxxxxxxxx> Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx> Cc: linux-ia64@xxxxxxxxxxxxxxx --- arch/ia64/kernel/smpboot.c | 2 -- 1 files changed, 0 insertions(+), 2 deletions(-) diff --git a/arch/ia64/kernel/smpboot.c b/arch/ia64/kernel/smpboot.c index 1113b8a..963d2db 100644 --- a/arch/ia64/kernel/smpboot.c +++ b/arch/ia64/kernel/smpboot.c @@ -382,7 +382,6 @@ smp_callin (void) set_numa_node(cpu_to_node_map[cpuid]); set_numa_mem(local_memory_node(cpu_to_node_map[cpuid])); - ipi_call_lock_irq(); spin_lock(&vector_lock); /* Setup the per cpu irq handling data structures */ __setup_vector_irq(cpuid); @@ -390,7 +389,6 @@ smp_callin (void) set_cpu_online(cpuid, true); per_cpu(cpu_state, cpuid) = CPU_ONLINE; spin_unlock(&vector_lock); - ipi_call_unlock_irq(); smp_setup_percpu_timer(); -- 1.7.5.4 -- To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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