From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755944Ab1HWWU2 (ORCPT ); Tue, 23 Aug 2011 18:20:28 -0400 Received: from mail-bw0-f46.google.com ([209.85.214.46]:44641 "EHLO mail-bw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755404Ab1HWWUQ (ORCPT ); Tue, 23 Aug 2011 18:20:16 -0400 From: Tejun Heo To: rjw@sisk.pl, paul@paulmenage.org, lizf@cn.fujitsu.com Cc: linux-pm@lists.linux-foundation.org, linux-kernel@vger.kernel.org, containers@lists.linux-foundation.org, Tejun Heo Subject: [PATCH 5/6] cgroup, cpuset: don't use ss->pre_attach() Date: Wed, 24 Aug 2011 00:19:59 +0200 Message-Id: <1314138000-2049-6-git-send-email-tj@kernel.org> X-Mailer: git-send-email 1.7.6 In-Reply-To: <1314138000-2049-1-git-send-email-tj@kernel.org> References: <1314138000-2049-1-git-send-email-tj@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ->pre_attach() is supposed to be called before migration, which is observed during process migration but task migration does it the other way around. The only ->pre_attach() user is cpuset which can do the same operaitons in ->can_attach(). Collapse cpuset_pre_attach() into cpuset_can_attach(). Signed-off-by: Tejun Heo Cc: Paul Menage Cc: Li Zefan --- Documentation/cgroups/cgroups.txt | 20 -------------------- kernel/cpuset.c | 29 ++++++++++++----------------- 2 files changed, 12 insertions(+), 37 deletions(-) diff --git a/Documentation/cgroups/cgroups.txt b/Documentation/cgroups/cgroups.txt index 2eee7cf..afb7cde 100644 --- a/Documentation/cgroups/cgroups.txt +++ b/Documentation/cgroups/cgroups.txt @@ -610,13 +610,6 @@ called on a fork. If this method returns 0 (success) then this should remain valid while the caller holds cgroup_mutex and it is ensured that either attach() or cancel_attach() will be called in future. -int can_attach_task(struct cgroup *cgrp, struct task_struct *tsk); -(cgroup_mutex held by caller) - -As can_attach, but for operations that must be run once per task to be -attached (possibly many when using cgroup_attach_proc). Called after -can_attach. - void cancel_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, struct cgroup_taskset *tset) (cgroup_mutex held by caller) @@ -627,12 +620,6 @@ function, so that the subsystem can implement a rollback. If not, not necessary. This will be called only about subsystems whose can_attach() operation have succeeded. The parameters are identical to can_attach(). -void pre_attach(struct cgroup *cgrp); -(cgroup_mutex held by caller) - -For any non-per-thread attachment work that needs to happen before -attach_task. Needed by cpuset. - void attach(struct cgroup_subsys *ss, struct cgroup *cgrp, struct cgroup_taskset *tset) (cgroup_mutex held by caller) @@ -641,13 +628,6 @@ Called after the task has been attached to the cgroup, to allow any post-attachment activity that requires memory allocations or blocking. The parameters are identical to can_attach(). -void attach_task(struct cgroup *cgrp, struct task_struct *tsk); -(cgroup_mutex held by caller) - -As attach, but for operations that must be run once per task to be attached, -like can_attach_task. Called before attach. Currently does not support any -subsystem that might need the old_cgrp for every thread in the group. - void fork(struct cgroup_subsy *ss, struct task_struct *task) Called when a task is forked into a cgroup. diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 472ddd6..f0b8df3 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -1367,6 +1367,15 @@ static int fmeter_getrate(struct fmeter *fmp) return val; } +/* + * Protected by cgroup_lock. The nodemasks must be stored globally because + * dynamically allocating them is not allowed in can_attach, and they must + * persist until attach. + */ +static cpumask_var_t cpus_attach; +static nodemask_t cpuset_attach_nodemask_from; +static nodemask_t cpuset_attach_nodemask_to; + /* Called by cgroups to determine if a cpuset is usable; cgroup_mutex held */ static int cpuset_can_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, struct cgroup_taskset *tset) @@ -1393,29 +1402,16 @@ static int cpuset_can_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, if ((ret = security_task_setscheduler(task))) return ret; } - return 0; -} - -/* - * Protected by cgroup_lock. The nodemasks must be stored globally because - * dynamically allocating them is not allowed in pre_attach, and they must - * persist among pre_attach, and attach. - */ -static cpumask_var_t cpus_attach; -static nodemask_t cpuset_attach_nodemask_from; -static nodemask_t cpuset_attach_nodemask_to; - -/* Set-up work for before attaching each task. */ -static void cpuset_pre_attach(struct cgroup *cont) -{ - struct cpuset *cs = cgroup_cs(cont); + /* prepare for attach */ if (cs == &top_cpuset) cpumask_copy(cpus_attach, cpu_possible_mask); else guarantee_online_cpus(cs, cpus_attach); guarantee_online_mems(cs, &cpuset_attach_nodemask_to); + + return 0; } static void cpuset_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, @@ -1901,7 +1897,6 @@ struct cgroup_subsys cpuset_subsys = { .create = cpuset_create, .destroy = cpuset_destroy, .can_attach = cpuset_can_attach, - .pre_attach = cpuset_pre_attach, .attach = cpuset_attach, .populate = cpuset_populate, .post_clone = cpuset_post_clone, -- 1.7.6