kernel/fork.c:copy_process(): consolidate the lockless CLONE_THREAD checks
authorOleg Nesterov <oleg@redhat.com>
Wed, 3 Jul 2013 22:08:32 +0000 (15:08 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Wed, 3 Jul 2013 23:08:03 +0000 (16:08 -0700)
commit18c830df771f2ba8b4699fea9af1492275ae627b
tree01b1dc470a1a30102a3f94e539bdbf74faa548be
parent8190773985141f063e1d6dc10200527c655abfb5
kernel/fork.c:copy_process(): consolidate the lockless CLONE_THREAD checks

copy_process() does a lot of "chaotic" initializations and checks
CLONE_THREAD twice before it takes tasklist.  In particular it sets
"p->group_leader = p" and then changes it again under tasklist if
!thread_group_leader(p).

This looks a bit confusing, lets create a single "if (CLONE_THREAD)" block
which initializes ->exit_signal, ->group_leader, and ->tgid.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Sergey Dyasly <dserrg@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel/fork.c