Hi Julien,
On 4/29/19 4:44 PM, Julien Grall wrote:
> its_irq_compose_msi_msg() may be called from non-preemptible context.
> However, on RT, iommu_dma_map_msi_msg requires to be called from a
> preemptible context.
>
> A recent change split iommu_dma_map_msi_msg() in two new functions:
> one that should be called in preemptible context, the other does
> not have any requirement.
>
> The GICv3 ITS driver is reworked to avoid executing preemptible code in
> non-preemptible context. This can be achieved by preparing the MSI
> maping when allocating the MSI interrupt.
mapping
>
> Signed-off-by: Julien Grall <julien.grall@xxxxxxx>
>
> ---
> Changes in v2:
> - Rework the commit message to use imperative mood
> ---
> drivers/irqchip/irq-gic-v3-its.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
> index 7577755bdcf4..12ddbcfe1b1e 100644
> --- a/drivers/irqchip/irq-gic-v3-its.c
> +++ b/drivers/irqchip/irq-gic-v3-its.c
> @@ -1179,7 +1179,7 @@ static void its_irq_compose_msi_msg(struct irq_data *d, struct msi_msg *msg)
> msg->address_hi = upper_32_bits(addr);
> msg->data = its_get_event_id(d);
>
> - iommu_dma_map_msi_msg(d->irq, msg);
> + iommu_dma_compose_msi_msg(irq_data_get_msi_desc(d), msg);
> }
>
> static int its_irq_set_irqchip_state(struct irq_data *d,
> @@ -2566,6 +2566,7 @@ static int its_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
> {
> msi_alloc_info_t *info = args;
> struct its_device *its_dev = info->scratchpad[0].ptr;
> + struct its_node *its = its_dev->its;
> irq_hw_number_t hwirq;
> int err;
> int i;
> @@ -2574,6 +2575,8 @@ static int its_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
> if (err)
> return err;
>
> + err = iommu_dma_prepare_msi(info->desc, its->get_msi_base(its_dev));
Test err as in gicv2m driver?
> +
> for (i = 0; i < nr_irqs; i++) {
> err = its_irq_gic_domain_alloc(domain, virq + i, hwirq + i);
> if (err)
>
Besides
Reviewed-by: Eric Auger <eric.auger@xxxxxxxxxx>
Thanks
Eric
