Re: [RFC PATCH v1 2/4] irqchip: GICv3: set non-percpu irqs status with _IRQ_MOVE_PCNTXT

From: Jiang Liu
Date: Sun Sep 06 2015 - 01:57:05 EST


On 2015/9/6 12:23, Yang Yingliang wrote:
> Use irq_settings_set_move_pcntxt() helper irqs status with
> _IRQ_MOVE_PCNTXT. So that it can do set affinity when calling
> irq_set_affinity_locked().
Hi Yingliang,
We could only set _IRQ_MOVE_PCNTCT flag to enable migrating
IRQ in process context if your hardware platform supports atomically
change IRQ configuration. Not sure whether that's true for GICv3.
If GICv3 doesn't support atomically change irq configuration, this
change may cause trouble.
Thanks!
Gerry

>
> Cc: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx>
> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
> Cc: Mark Rutland <mark.rutland@xxxxxxx>
> Cc: Will Deacon <will.deacon@xxxxxxx>
> Cc: Russell King - ARM Linux <linux@xxxxxxxxxxxxxxxx>
> Cc: Hanjun Guo <hanjun.guo@xxxxxxxxxx>
> Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx>
> ---
> drivers/irqchip/irq-gic-v3.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
> index e406bc5..9108387 100644
> --- a/drivers/irqchip/irq-gic-v3.c
> +++ b/drivers/irqchip/irq-gic-v3.c
> @@ -688,6 +688,7 @@ static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
> irq_domain_set_info(d, irq, hw, &gic_chip, d->host_data,
> handle_fasteoi_irq, NULL, NULL);
> set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
> + irq_set_move_pcntxt(irq);
> }
> /* LPIs */
> if (hw >= 8192 && hw < GIC_ID_NR) {
> @@ -696,6 +697,7 @@ static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
> irq_domain_set_info(d, irq, hw, &gic_chip, d->host_data,
> handle_fasteoi_irq, NULL, NULL);
> set_irq_flags(irq, IRQF_VALID);
> + irq_set_move_pcntxt(irq);
> }
>
> return 0;
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/