aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorJoerg Roedel <joerg.roedel@amd.com>2008-09-04 19:01:02 +0200
committerIngo Molnar <mingo@elte.hu>2008-09-19 12:59:08 +0200
commit5507eef835c9c941e69d6d96e4b43af23eeb4ac9 (patch)
tree3072e37193035e1f2ff6a37e265a8bddadbad640
parent1c65577398589bb44ab0980f9b9d30804b48a5db (diff)
downloadkernel_samsung_smdk4412-5507eef835c9c941e69d6d96e4b43af23eeb4ac9.zip
kernel_samsung_smdk4412-5507eef835c9c941e69d6d96e4b43af23eeb4ac9.tar.gz
kernel_samsung_smdk4412-5507eef835c9c941e69d6d96e4b43af23eeb4ac9.tar.bz2
AMD IOMMU: add branch hints to completion wait checks
This patch adds branch hints to the cecks if a completion_wait is necessary. The completion_waits in the mapping paths are unlikly because they will only happen on software implementations of AMD IOMMU which don't exists today or with lazy IO/TLB flushing when the allocator wraps around the address space. With lazy IO/TLB flushing the completion_wait in the unmapping path is unlikely too. Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
-rw-r--r--arch/x86/kernel/amd_iommu.c12
1 files changed, 6 insertions, 6 deletions
diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index 679f2a8..d743aa0 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -876,7 +876,7 @@ static dma_addr_t map_single(struct device *dev, phys_addr_t paddr,
if (addr == bad_dma_address)
goto out;
- if (iommu->need_sync)
+ if (unlikely(iommu->need_sync))
iommu_completion_wait(iommu);
out:
@@ -905,7 +905,7 @@ static void unmap_single(struct device *dev, dma_addr_t dma_addr,
__unmap_single(iommu, domain->priv, dma_addr, size, dir);
- if (iommu->need_sync)
+ if (unlikely(iommu->need_sync))
iommu_completion_wait(iommu);
spin_unlock_irqrestore(&domain->lock, flags);
@@ -968,7 +968,7 @@ static int map_sg(struct device *dev, struct scatterlist *sglist,
goto unmap;
}
- if (iommu->need_sync)
+ if (unlikely(iommu->need_sync))
iommu_completion_wait(iommu);
out:
@@ -1014,7 +1014,7 @@ static void unmap_sg(struct device *dev, struct scatterlist *sglist,
s->dma_address = s->dma_length = 0;
}
- if (iommu->need_sync)
+ if (unlikely(iommu->need_sync))
iommu_completion_wait(iommu);
spin_unlock_irqrestore(&domain->lock, flags);
@@ -1061,7 +1061,7 @@ static void *alloc_coherent(struct device *dev, size_t size,
goto out;
}
- if (iommu->need_sync)
+ if (unlikely(iommu->need_sync))
iommu_completion_wait(iommu);
out:
@@ -1093,7 +1093,7 @@ static void free_coherent(struct device *dev, size_t size,
__unmap_single(iommu, domain->priv, dma_addr, size, DMA_BIDIRECTIONAL);
- if (iommu->need_sync)
+ if (unlikely(iommu->need_sync))
iommu_completion_wait(iommu);
spin_unlock_irqrestore(&domain->lock, flags);