Re: [PATCH v2 3/4] iommu/iova: Extend rbtree node caching

2017-09-19 Thread Robin Murphy
On 19/09/17 10:42, Leizhen (ThunderTown) wrote: [...] static void __cached_rbnode_delete_update(struct iova_domain *iovad, struct iova *free) { struct iova *cached_iova; -struct rb_node *curr; +struct rb_node **curr = NULL; -if

Re: [PATCH v2 3/4] iommu/iova: Extend rbtree node caching

2017-09-19 Thread Robin Murphy
On 19/09/17 10:42, Leizhen (ThunderTown) wrote: [...] static void __cached_rbnode_delete_update(struct iova_domain *iovad, struct iova *free) { struct iova *cached_iova; -struct rb_node *curr; +struct rb_node **curr = NULL; -if

Re: [PATCH v2 3/4] iommu/iova: Extend rbtree node caching

2017-09-19 Thread Leizhen (ThunderTown)
On 2017/7/31 19:42, Robin Murphy wrote: > Hi Nate, > > On 29/07/17 04:57, Nate Watterson wrote: >> Hi Robin, >> I am seeing a crash when performing very basic testing on this series >> with a Mellanox CX4 NIC. I dug into the crash a bit, and think this >> patch is the culprit, but this rcache

Re: [PATCH v2 3/4] iommu/iova: Extend rbtree node caching

2017-09-19 Thread Leizhen (ThunderTown)
On 2017/7/31 19:42, Robin Murphy wrote: > Hi Nate, > > On 29/07/17 04:57, Nate Watterson wrote: >> Hi Robin, >> I am seeing a crash when performing very basic testing on this series >> with a Mellanox CX4 NIC. I dug into the crash a bit, and think this >> patch is the culprit, but this rcache

Re: [PATCH v2 3/4] iommu/iova: Extend rbtree node caching

2017-08-31 Thread Leizhen (ThunderTown)
On 2017/8/4 3:41, Nate Watterson wrote: > Hi Robin, > > On 7/31/2017 7:42 AM, Robin Murphy wrote: >> Hi Nate, >> >> On 29/07/17 04:57, Nate Watterson wrote: >>> Hi Robin, >>> I am seeing a crash when performing very basic testing on this series >>> with a Mellanox CX4 NIC. I dug into the crash

Re: [PATCH v2 3/4] iommu/iova: Extend rbtree node caching

2017-08-31 Thread Leizhen (ThunderTown)
On 2017/8/4 3:41, Nate Watterson wrote: > Hi Robin, > > On 7/31/2017 7:42 AM, Robin Murphy wrote: >> Hi Nate, >> >> On 29/07/17 04:57, Nate Watterson wrote: >>> Hi Robin, >>> I am seeing a crash when performing very basic testing on this series >>> with a Mellanox CX4 NIC. I dug into the crash

Re: [PATCH v2 3/4] iommu/iova: Extend rbtree node caching

2017-08-03 Thread Nate Watterson
Hi Robin, On 7/31/2017 7:42 AM, Robin Murphy wrote: Hi Nate, On 29/07/17 04:57, Nate Watterson wrote: Hi Robin, I am seeing a crash when performing very basic testing on this series with a Mellanox CX4 NIC. I dug into the crash a bit, and think this patch is the culprit, but this rcache

Re: [PATCH v2 3/4] iommu/iova: Extend rbtree node caching

2017-08-03 Thread Nate Watterson
Hi Robin, On 7/31/2017 7:42 AM, Robin Murphy wrote: Hi Nate, On 29/07/17 04:57, Nate Watterson wrote: Hi Robin, I am seeing a crash when performing very basic testing on this series with a Mellanox CX4 NIC. I dug into the crash a bit, and think this patch is the culprit, but this rcache

Re: [PATCH v2 3/4] iommu/iova: Extend rbtree node caching

2017-07-31 Thread Robin Murphy
Hi Nate, On 29/07/17 04:57, Nate Watterson wrote: > Hi Robin, > I am seeing a crash when performing very basic testing on this series > with a Mellanox CX4 NIC. I dug into the crash a bit, and think this > patch is the culprit, but this rcache business is still mostly > witchcraft to me. > > #

Re: [PATCH v2 3/4] iommu/iova: Extend rbtree node caching

2017-07-31 Thread Robin Murphy
Hi Nate, On 29/07/17 04:57, Nate Watterson wrote: > Hi Robin, > I am seeing a crash when performing very basic testing on this series > with a Mellanox CX4 NIC. I dug into the crash a bit, and think this > patch is the culprit, but this rcache business is still mostly > witchcraft to me. > > #

Re: [PATCH v2 3/4] iommu/iova: Extend rbtree node caching

2017-07-28 Thread Nate Watterson
Hi Robin, I am seeing a crash when performing very basic testing on this series with a Mellanox CX4 NIC. I dug into the crash a bit, and think this patch is the culprit, but this rcache business is still mostly witchcraft to me. # ifconfig eth5 up # ifconfig eth5 down Unable to handle kernel

Re: [PATCH v2 3/4] iommu/iova: Extend rbtree node caching

2017-07-28 Thread Nate Watterson
Hi Robin, I am seeing a crash when performing very basic testing on this series with a Mellanox CX4 NIC. I dug into the crash a bit, and think this patch is the culprit, but this rcache business is still mostly witchcraft to me. # ifconfig eth5 up # ifconfig eth5 down Unable to handle kernel

[PATCH v2 3/4] iommu/iova: Extend rbtree node caching

2017-07-21 Thread Robin Murphy
The cached node mechanism provides a significant performance benefit for allocations using a 32-bit DMA mask, but in the case of non-PCI devices or where the 32-bit space is full, the loss of this benefit can be significant - on large systems there can be many thousands of entries in the tree,

[PATCH v2 3/4] iommu/iova: Extend rbtree node caching

2017-07-21 Thread Robin Murphy
The cached node mechanism provides a significant performance benefit for allocations using a 32-bit DMA mask, but in the case of non-PCI devices or where the 32-bit space is full, the loss of this benefit can be significant - on large systems there can be many thousands of entries in the tree,