xfs_vm_readpage(
	struct file		*unused,
	struct page		*page)
{
	trace_xfs_vm_readpage(page->mapping->host, 1);
	return mpage_readpage(page, xfs_get_blocks);
}

The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.