Messages in this thread | | | Date | Sat, 25 Aug 2007 20:26:06 +0400 | From | Oleg Nesterov <> | Subject | cpuset: attach_task() vs sched_setaffinity() race? |
| |
After the brief look at kernel/cpuset.c, it seems that attach_task() should guarantee that the task can't use CPUs outside of cpuset->cpus_allowed.
But this looks racy wrt sched_setaffinity() which does
cpus_allowed = cpuset_cpus_allowed(p); // callback_mutex is free set_cpus_allowed(p);
What if attach_task()->set_cpus_allowed() happens in between?
Another question: update_cpumask(cs) does nothing with the tasks attached to that cpuset, why? It may take a while before the task actually migrates to the new CPU.
Thanks,
Oleg.
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |