Re: [shm][hugetlb] Fix get_policy for stacked shared memory files

From: William Lee Irwin III
Date: Mon Jun 11 2007 - 23:50:57 EST

On Mon, Jun 11, 2007 at 04:34:54PM -0500, Adam Litke wrote:
> Here's another breakage as a result of shared memory stacked files :(
> The NUMA policy for a VMA is determined by checking the following (in
> the order given):
> 1) vma->vm_ops->get_policy() (if defined)
> 2) vma->vm_policy (if defined)
> 3) task->mempolicy (if defined)
> 4) Fall back to default_policy
> By switching to stacked files for shared memory, get_policy() is now
> always set to shm_get_policy which is a wrapper function. This
> causes us to stop at step 1, which yields NULL for hugetlb instead of
> task->mempolicy which was the previous (and correct) result.
> This patch modifies the shm_get_policy() wrapper to maintain steps 1-3 for the
> wrapped vm_ops. Andi and Christoph, does this look right to you?
> Signed-off-by: Adam Litke <agl@xxxxxxxxxx>

Thanks for fielding this. The fix is certainly clear enough.

Acked-by: William Irwin <bill.irwin@xxxxxxxxxx>

-- wli
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