From: Oleg Nesterov <oleg@tv-sign.ru>
Date: Mon, 2 Oct 2006 09:18:54 +0000 (-0700)
Subject: [PATCH] proc: drop tasklist lock in task_state()
X-Git-Tag: v2.6.19-rc1~384
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b0fa9db6abdb2875a6d3069ddc6a2846a73fa5cd;p=pandora-kernel.git

[PATCH] proc: drop tasklist lock in task_state()

task_state() needs tasklist_lock to protect ->parent/->real_parent.  However
task->parent points to nowhere only when the actions below happen in order

	1) release_task(task)
	2) release_task(task->parent)
	3) a grace period passed

But 3) implies that the memory ops from 1) should be finished, so pid_alive()
can't be true in such a case.

Otherwise, we don't care if ->parent/->real_parent changes under us.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---

Reading git-diff-tree failed