Re: [RFC v9 24/29] hw/arm/smmuv3: Fill the IOTLBEntry leaf field on NH_VA invalidation

From: Kunkun Jiang <jiangkunkun@huawei.com>
To: Eric Auger <eric.auger@redhat.com>, <eric.auger.pro@gmail.com>,
	<qemu-devel@nongnu.org>, <qemu-arm@nongnu.org>,
	<alex.williamson@redhat.com>
Cc: peter.maydell@linaro.org, jacob.jun.pan@linux.intel.com,
	jean-philippe@linaro.org, tn@semihalf.com,
	chenxiang66@hisilicon.com, shameerali.kolothum.thodi@huawei.com,
	nicoleotsuka@gmail.com, vivek.gautam@arm.com, vdumpa@nvidia.com,
	yi.l.liu@intel.com, peterx@redhat.com, zhangfei.gao@gmail.com,
	yuzenghui@huawei.com, wanghaibin.wang@huawei.com,
	zhukeqian1@huawei.com
Subject: Re: [RFC v9 24/29] hw/arm/smmuv3: Fill the IOTLBEntry leaf field on NH_VA invalidation
Date: Thu, 13 May 2021 15:09:21 +0800	[thread overview]
Message-ID: <1c70fb86-fb4b-e26c-8022-bd19b073d8fe@huawei.com> (raw)
In-Reply-To: <20210411120912.15770-25-eric.auger@redhat.com>

Hi Eric,

On 2021/4/11 20:09, Eric Auger wrote:
> Let's propagate the leaf attribute throughout the invalidation path.
> This hint is used to reduce the scope of the invalidations to the
> last level of translation. Not enforcing it induces large performance
> penalties in nested mode.
>
> Signed-off-by: Eric Auger <eric.auger@redhat.com>
> ---
>   hw/arm/smmuv3.c | 9 +++++----
>   1 file changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/hw/arm/smmuv3.c b/hw/arm/smmuv3.c
> index 7beb55cd89..74a6408146 100644
> --- a/hw/arm/smmuv3.c
> +++ b/hw/arm/smmuv3.c
> @@ -799,7 +799,7 @@ epilogue:
>   static void smmuv3_notify_iova(IOMMUMemoryRegion *mr,
>                                  IOMMUNotifier *n,
>                                  int asid, dma_addr_t iova,
> -                               uint8_t tg, uint64_t num_pages)
> +                               uint8_t tg, uint64_t num_pages, bool leaf)
>   {
>       SMMUDevice *sdev = container_of(mr, SMMUDevice, iommu);
>       IOMMUTLBEvent event = {};
> @@ -834,6 +834,7 @@ static void smmuv3_notify_iova(IOMMUMemoryRegion *mr,
>       event.entry.perm = IOMMU_NONE;
>       event.entry.flags = IOMMU_INV_FLAGS_ARCHID;
>       event.entry.arch_id = asid;
> +    event.entry.leaf = leaf;
>   
>       memory_region_notify_iommu_one(n, &event);
>   }
> @@ -865,7 +866,7 @@ static void smmuv3_notify_asid(IOMMUMemoryRegion *mr,
>   
>   /* invalidate an asid/iova range tuple in all mr's */
>   static void smmuv3_inv_notifiers_iova(SMMUState *s, int asid, dma_addr_t iova,
> -                                      uint8_t tg, uint64_t num_pages)
> +                                      uint8_t tg, uint64_t num_pages, bool leaf)
>   {
>       SMMUDevice *sdev;
Does the parameter 'leaf' need to be added to the trace?
> trace_smmuv3_inv_notifiers_iova(mr->parent_obj.name, asid, iova,
>                                         tg, num_pages);

Thanks,
Kunkun Jiang
>   
> @@ -877,7 +878,7 @@ static void smmuv3_inv_notifiers_iova(SMMUState *s, int asid, dma_addr_t iova,
>                                           tg, num_pages);
>   
>           IOMMU_NOTIFIER_FOREACH(n, mr) {
> -            smmuv3_notify_iova(mr, n, asid, iova, tg, num_pages);
> +            smmuv3_notify_iova(mr, n, asid, iova, tg, num_pages, leaf);
>           }
>       }
>   }
> @@ -915,7 +916,7 @@ static void smmuv3_s1_range_inval(SMMUState *s, Cmd *cmd)
>           count = mask + 1;
>   
>           trace_smmuv3_s1_range_inval(vmid, asid, addr, tg, count, ttl, leaf);
> -        smmuv3_inv_notifiers_iova(s, asid, addr, tg, count);
> +        smmuv3_inv_notifiers_iova(s, asid, addr, tg, count, leaf);
>           smmu_iotlb_inv_iova(s, asid, addr, tg, count, ttl);
>   
>           num_pages -= count;