[lkml]   [2009]   [Aug]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH 6/6] Makes procs file writable to move all threads by tgid at once
On Mon, Aug 3, 2009 at 12:45 PM, Serge E. Hallyn<> wrote:
> This is probably a stupid idea, but...  what about having zero
> overhead at clone(), and instead, at cgroup_task_migrate(),
> dequeue_task()ing all of the affected threads for the duration of
> the migrate?

Or a simpler alternative - rather than taking the thread group
leader's rwsem in cgroup_fork(), always take current's rwsem. Then
you're always locking a (probably?) local rwsem and minimizing the
overhead. So not quite zero overhead in the fork path, but I'd be
surprised if it was measurable. In cgroup_attach_proc() you then have
to take the rwsem of every thread in the process. Kind of the
equivalent of a per-threadgroup big-reader lock.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2009-08-04 20:53    [W:0.062 / U:0.968 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site