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

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



David wrote:
> If something that was previously unaccepted is now allowed with a 
> newly-introduced semantic, that's an API change.

Agreed, as I wrote earlier:
> It should work with libnuma and be
> fully upward compatible with current code (except perhaps code that
> depends on getting an error from requesting MPOL_INTERLEAVE on a node
> not allowed.)

Without at least this sort of change to MPOL_INTERLEAVE nodemasks,
allowing either empty nodemasks (Lee's proposal) or extending them
outside the current cpuset (what I'm cooking up now), there is no way
for a task that is currently confined to a single node cpuset to say
anything about how it wants be interleaved in the event that it is
subsequently moved to a larger cpuset.  Currently, such a task is only
allowed to pass exactly one particular nodemask to set_mempolicy
MPOL_INTERLEAVE calls, with exactly the one bit corresponding to its
current node.  No useful information can be passed via an API that only
allows a single legal value.

But you knew that ...

You were just correcting my erroneously unqualified statement.  Good.

-- 
                  I won't rest till it's the best ...
                  Programmer, Linux Scalability
                  Paul Jackson <[email protected]> 1.925.600.0401
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux