"Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxx> writes:
> This syscall can be used to set a home node for the MPOL_BIND
> and MPOL_PREFERRED_MANY memory policy. Users should use this
> syscall after setting up a memory policy for the specified range
> as shown below.
So I noticed one little thing as I was looking at this...
[...]
> +SYSCALL_DEFINE4(set_mempolicy_home_node, unsigned long, start, unsigned long, len,
> + unsigned long, home_node, unsigned long, flags)
> +{
> + struct mm_struct *mm = current->mm;
> + struct vm_area_struct *vma;
> + struct mempolicy *new;
> + unsigned long vmstart;
> + unsigned long vmend;
> + unsigned long end;
> + int err = -ENOENT;
> +
> + if (start & ~PAGE_MASK)
> + return -EINVAL;
> +
> + len = (len + PAGE_SIZE - 1) & PAGE_MASK;
> + end = start + len;
> +
> + if (end < start)
> + return -EINVAL;
> + if (end == start)
> + return 0;
> + mmap_write_lock(mm);
> + vma = find_vma(mm, start);
> + for (; vma && vma->vm_start < end; vma = vma->vm_next) {
> +
> + vmstart = max(start, vma->vm_start);
> + vmend = min(end, vma->vm_end);
> + new = mpol_dup(vma_policy(vma));
> + if (IS_ERR(new)) {
> + err = PTR_ERR(new);
> + break;
> + }
> + /*
> + * Only update home node if there is an existing vma policy
> + */
> + if (!new)
> + continue;
> + new->home_node = home_node;
> + err = mbind_range(mm, vmstart, vmend, new);
> + if (err)
> + break;
> + }
> + mmap_write_unlock(mm);
> + return err;
> +}
You never do anything with flags; I believe you want to check and ensure
that it's zero if there are no defined flags at this point?
Thanks,
jon
