Re: [patch 2/2] cpusets: add interleave_over_allowed option

Paul Jackson
2007-10-29T20:02:30Z

Lee wrote:
> In libnuma in numactl-1.0.2 that I recently grabbed off Andi's site,
> numa_available() indeed issues this call. But, I don't see any internal
> calls to numa_available() [comments says all other calls undefined when
> numa_available() returns an error] nor any other calls to
> get_mempolicy() with all null/0 args. So, you'd be depending on the
> application to call numa_available().

Aha - good point. It happened to be the numactl command line utility
that I tested with that issued the get_mempolicy(0,0,0,0,0) call.

Yup - this proposed hack, to have the kernel revert to the original
memory policy nodemask numbering if it sees such a getmempolicy call
is now officially dead meat.

Thanks.

> However, you could define an
> additional MPOL_F_* flag to get_mempolicy() that is issued in library
> init code to enable new behavior--again, based on some indication that
> new behavior is desired or not.

Yes - I am intending to define such MPOL_F_* flags, to set and get
which behavior applies to the current task.

--
I won't rest till it's the best ...
Programmer, Linux Scalability
Paul Jackson <pj@sgi.com> 1.925.600.0401