Re: PATCH] Use -mpreferred-stack-boundary=3 on x86-64 if supported

Andi Kleen
2012-06-23T16:13:32Z

> This patch uses -mpreferred-stack-boundary=3 on x86-64 if it is supported.
> I have been running 3.4 kernel compiled with this option for weeks.

But why?

All the SSE code in the kernel should adjust manually. And the other
code doesn't need it.

Besides the entry points do not guarantee alignment.

For the kernel it would be probably more useful to have a attribute
per function that forces alignment.

-Andi
--
ak@linux.intel.com -- Speaking for myself only.