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| author |   Joerg Roedel <joerg.roedel@amd.com> | 2008-09-04 19:01:02 +0200 |
|---|---|---|
| committer |   Ingo Molnar <mingo@elte.hu> | 2008-09-19 12:59:08 +0200 |
| commit | 5507eef835c9c941e69d6d96e4b43af23eeb4ac9 (patch) | |
| tree | 3072e37193035e1f2ff6a37e265a8bddadbad640 /arch/x86/kernel/amd_iommu.c | |
| parent | AMD IOMMU: implement lazy IO/TLB flushing (diff) | |
| download | linux-dev-5507eef835c9c941e69d6d96e4b43af23eeb4ac9.tar.xz linux-dev-5507eef835c9c941e69d6d96e4b43af23eeb4ac9.zip | |
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>
Diffstat (limited to 'arch/x86/kernel/amd_iommu.c')
| -rw-r--r-- | arch/x86/kernel/amd_iommu.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index 679f2a8e22ee..d743aa0adccc 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); |