Re: [PATCH 1/3] mm/migrate: clean up useless code in migrate_vma_collect_pmd()

[Matthew Wilcox]

This needs something beyond the subject line.  Maybe ...

After these assignments, we either restart the loop with a fresh variable,
or we assign to the variable again without using the value we've assigned.

Reviewed-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>

>  			goto next;
>  		}
> -		pfn = page_to_pfn(page);

After you've done all this, as far as I can tell, the 'pfn' variable is
only used in one arm of the conditions, so it can be moved there.

ie something like:

-               unsigned long mpfn, pfn;
+               unsigned long mpfn;
...
-               pfn = pte_pfn(pte);
...
+                       unsigned long pfn = pte_pfn(pte);
+