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drm/ttm: Use VM_PFNMAP for shared bo maps

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VM_PFNMAP is faster than VM_MIXEDMAP due to reduced page administration so
use it for shared maps where we don't have any Copy-On-Write pages. For
private maps, we continue to use VM_MIXEDMAP.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
This commit is contained in:
Thomas Hellstrom 2014-01-03 09:21:54 +01:00
parent 859ae233cd
commit 7dfe8b6187
1 changed files with 15 additions and 3 deletions
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18
drivers/gpu/drm/ttm/ttm_bo_vm.c
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@ -220,7 +220,11 @@ static int ttm_bo_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
pfn = page_to_pfn(page);
}
ret = vm_insert_mixed(&cvma, address, pfn);
if (vma->vm_flags & VM_MIXEDMAP)
ret = vm_insert_mixed(&cvma, address, pfn);
else
ret = vm_insert_pfn(&cvma, address, pfn);
/*
* Somebody beat us to this PTE or prefaulting to
* an already populated PTE, or prefaulting error.
@ -319,7 +323,14 @@ int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma,
*/
vma->vm_private_data = bo;
vma->vm_flags |= VM_IO | VM_MIXEDMAP | VM_DONTEXPAND | VM_DONTDUMP;
/*
* PFNMAP is faster than MIXEDMAP due to reduced page
* administration. So use MIXEDMAP only if private VMA, where
* we need to support COW.
*/
vma->vm_flags |= (vma->vm_flags & VM_SHARED) ? VM_PFNMAP : VM_MIXEDMAP;
vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
return 0;
out_unref:
ttm_bo_unref(&bo);
@ -334,7 +345,8 @@ int ttm_fbdev_mmap(struct vm_area_struct *vma, struct ttm_buffer_object *bo)
vma->vm_ops = &ttm_bo_vm_ops;
vma->vm_private_data = ttm_bo_reference(bo);
vma->vm_flags |= VM_IO | VM_MIXEDMAP | VM_DONTEXPAND;
vma->vm_flags |= (vma->vm_flags & VM_SHARED) ? VM_PFNMAP : VM_MIXEDMAP;
vma->vm_flags |= VM_IO | VM_DONTEXPAND;
return 0;
}
EXPORT_SYMBOL(ttm_fbdev_mmap);