Re: [PATCH] irqchip/gic-v3: Use wmb() instead of smb_wmb() in gic_raise_softirq()

From: Barry Song
Date: Fri Feb 18 2022 - 06:28:14 EST


> --- a/drivers/irqchip/irq-gic-v3.c
> +++ b/drivers/irqchip/irq-gic-v3.c
> @@ -688,7 +688,7 @@ static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
> * Ensure that stores to Normal memory are visible to the
> * other CPUs before issuing the IPI.
> */
> - smp_wmb();
> + wmb();

Sorry for waking up the old thread. isn't dsb(ishst) enough here as we only
need to guarantee the visibility of data to other CPUs in smp inner domain
before we send the ipi?

>
> for_each_cpu(cpu, mask) {
> u64 cluster_id = MPIDR_TO_SGI_CLUSTER_ID(cpu_logical_map(cpu));

Thanks
Barry