diff options
| author | Xiang Chen <chenxiang66@hisilicon.com> | 2021-03-25 11:38:24 +0800 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2021-04-07 10:23:58 +0200 |
| commit | 3431c3f660a39f6ced954548a59dba6541ce3eb1 (patch) | |
| tree | 3064657245bb795be6add23b086560faf710162e | |
| parent | e49d033bddf5b565044e2abe4241353959bc9120 (diff) | |
iommu: Fix a boundary issue to avoid performance drop
After the change of patch ("iommu: Switch gather->end to the
inclusive end"), the performace drops from 1600+K IOPS to 1200K in our
kunpeng ARM64 platform.
We find that the range [start1, end1) actually is joint from the range
[end1, end2), but it is considered as disjoint after the change,
so it needs more times of TLB sync, and spends more time on it.
So fix the boundary issue to avoid performance drop.
Fixes: 862c3715de8f ("iommu: Switch gather->end to the inclusive end")
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/1616643504-120688-1-git-send-email-chenxiang66@hisilicon.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
| -rw-r--r-- | include/linux/iommu.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 5e7fe519430a..9ca6e6b8084d 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -547,7 +547,7 @@ static inline void iommu_iotlb_gather_add_page(struct iommu_domain *domain, * structure can be rewritten. */ if (gather->pgsize != size || - end < gather->start || start > gather->end) { + end + 1 < gather->start || start > gather->end + 1) { if (gather->pgsize) iommu_iotlb_sync(domain, gather); gather->pgsize = size; |