Re: [rfc] forked kernel task and mm structures imbalanced on NUMA

Peter Zijlstra
2010-06-01T08:49:59Z

On Tue, 2010-06-01 at 10:16 +0200, Peter Zijlstra wrote:
> I'd have to again look at wth happens to ->cpus_allowed, but I guess
> it should be fixable

Ah, I remember, cgroup_clone was a massive pain, Serge said he'd wanted
to kill that, but I don't think that ever happened.

copy_process():
if (current->nsproxy != p->nsproxy)
ns_cgroup_clone()
cgroup_clone()
mutex_lock(inode->i_mutex)
mutex_lock(cgroup_mutex)
cgroup_attach_task()
ss->can_attach()
ss->attach() [ -> cpuset_attach() ]
cpuset_attach_task()
set_cpus_allowed_ptr();

was the code path that made set_cpus_allowed_ptr() exclusion against
fork interesting.