vmstat's entries type

[Chuck Swiger]

Peter Jeremy wrote:
[ ... ]
> This was based on an examination of /usr/src/sys/*/include/atomic.h.
> It looks like I was overly quick because the RISC architectures are
> using compare-and-swap, rather than test-and-set primitives - sorry
> about the error.  The details are:
[ ... ]
> - ppc doesn't support 64-bit atomic operations

lwarx/stwcx...?

http://publibn.boulder.ibm.com/doc_link/en_US/a_doc_lib/aixassem/alangref/lwarx.htm
http://www-128.ibm.com/developerworks/library/pa-atom/

> - sparc64 uses cas in a loop.
> 
> Whilst true spinlocks are not needed, amd64 is the only architecture
> FreeBSD supports that does not require some sort of loop to perform
> a 64-bit atomic operation.

You can use membar instructions on the SPARCv9 to enforce various memory 
models (RMO, PSO, TSO, if not full sequential consistency).

-- 
-Chuck