tree cd3a29086e5274fd08bc8d22d15568deab144755
parent 181ae4005d0a4010802be534d929b38c42b9ac06
author Eric W. Biederman <ebiederm@xmission.com> 1145424016 -0700
committer Linus Torvalds <torvalds@g5.osdl.org> 1145463229 -0700

[PATCH] task: Make task list manipulations RCU safe

While we can currently walk through thread groups, process groups, and
sessions with just the rcu_read_lock, this opens the door to walking the
entire task list.

We already have all of the other RCU guarantees so there is no cost in
doing this, this should be enough so that proc can stop taking the
tasklist lock during readdir.

prev_task was killed because it has no users, and using it will miss new
tasks when doing an rcu traversal.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>