On Wed, 11 Dec 2013, Dave Hansen wrote: > > The write-argument to cmpxchg_double() must be 16-byte aligned. > We used to align 'struct page' itself in order to guarantee this, > but that wastes 8-bytes per page. Instead, we take 8-bytes > internal to the page before page->counters and move freelist > between there and the existing 8-bytes after counters. That way, > no matter how 'stuct page' itself is aligned, we can ensure that > we have a 16-byte area with which to to this cmpxchg.
Well this adds additional branching to the fast paths. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
