On Mon, Sep 27, 2021 at 03:24:47PM -0700, Song Liu wrote:
> OTOH, does it make sense to block writes within khugepaged, like:
> @@ -1652,6 +1653,11 @@ static void collapse_file(struct mm_struct *mm,
> /* Only allocate from the target node */
> gfp = alloc_hugepage_khugepaged_gfpmask() | __GFP_THISNODE;
>
> + if (deny_write_access(file)) {
> + result = SCAN_BUSY_WRITE;
> + return;
> + }
The problem is that it denies, rather than blocking. That means that the
writer gets ETXTBSY instead of waiting until khugepaged is done.
