Re: Is there a way to obtain a machine's cache line size?

[Eduardo Horvath <eeh%NetBSD.org@localhost>]

On Thu, 20 Jan 2011, Dennis Ferguson wrote:

> On 20 Jan 2011, at 11:59 , Dennis Ferguson wrote:
> > Is there a way to obtain the correct cache line size for the machine
> > code is running on, both in the kernel and at user level?
> 
> I found it.  It is "coherency_unit" in the kernel (it is an
> appropriately small number, rather than the cache line size,
> in uniprocessor kernels), but doesn't seem to be exposed outside
> of there.

What type of machine are we talking here?  The powerpc ports have a system 
call to tell userland what the CPU's cache line size is.  I needed to add 
it to support IBM403s (or was it 401s?) which ISTR have a 16-byte cache 
line.  Look at the libc memcpy/memset code.

Edaurdo