lkml.org 
[lkml]   [2007]   [Aug]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
Subjectcpuset: 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/

\
 
 \ /
  Last update: 2007-08-25 18:27    [W:0.041 / U:0.936 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site