cvs commit: src/sys/i386/i386 support.s src/sys/i386/include md_var.h

[Alan Cox]

On Wed, Oct 01, 2003 at 01:39:03AM -0400, Jeff Roberson wrote:
> This moves data 3.8x faster than bzero on my laptop.  In a moment I will
> commit pmap bits to make use of it.  This improved my 'make kernel' times
> by almost 2%.  It will do even better in workloads that demand a lot of
> zero pages.
> 

An sfence at the end of sse2_pagezero() is probably prudent.

Alan

> On Tue, 30 Sep 2003, Jeff Roberson wrote:
> 
> > jeff        2003/09/30 22:25:27 PDT
> >
> >   FreeBSD src repository
> >
> >   Modified files:
> >     sys/i386/i386        support.s
> >     sys/i386/include     md_var.h
> >   Log:
> >    - Add ss2_pagezero() for zeroing pages using the movnti instruction.  This
> >      instruction is enabled with SSE2 but does not use SSE registers.  It is a
> >      "non-temporal" move which bypasses the cache and does not dirty lines.
> >
> >   Revision  Changes    Path
> >   1.98      +14 -0     src/sys/i386/i386/support.s
> >   1.65      +1 -0      src/sys/i386/include/md_var.h
> >