Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756244AbaGPJpO (ORCPT ); Wed, 16 Jul 2014 05:45:14 -0400 Received: from cantor2.suse.de ([195.135.220.15]:49058 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753938AbaGPJpJ (ORCPT ); Wed, 16 Jul 2014 05:45:09 -0400 Date: Wed, 16 Jul 2014 11:45:07 +0200 From: Michal Hocko To: Tejun Heo Cc: lizefan@huawei.com, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Johannes Weiner , "Aneesh Kumar K.V" Subject: Re: [PATCH 3/6] cgroup: replace cgroup_add_cftypes() with cgroup_add_legacy_cftypes() Message-ID: <20140716094507.GG7121@dhcp22.suse.cz> References: <1405352648-4279-1-git-send-email-tj@kernel.org> <1405352648-4279-4-git-send-email-tj@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1405352648-4279-4-git-send-email-tj@kernel.org> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon 14-07-14 11:44:05, Tejun Heo wrote: > Currently, cftypes added by cgroup_add_cftypes() are used for both the > unified default hierarchy and legacy ones and subsystems can mark each > file with either CFTYPE_ONLY_ON_DFL or CFTYPE_INSANE if it has to > appear only on one of them. This is quite hairy and error-prone. > Also, we may end up exposing interface files to the default hierarchy > without thinking it through. > > cgroup_subsys will grow two separate cftype addition functions and > apply each only on the hierarchies of the matching type. This will > allow organizing cftypes in a lot clearer way and encourage subsystems > to scrutinize the interface which is being exposed in the new default > hierarchy. > > In preparation, this patch adds cgroup_add_legacy_cftypes() which > currently is a simple wrapper around cgroup_add_cftypes() and replaces > all cgroup_add_cftypes() usages with it. > > While at it, this patch drops a completely spurious return from > __hugetlb_cgroup_file_init(). > > This patch doesn't introduce any functional differences. > > Signed-off-by: Tejun Heo > Acked-by: Neil Horman > Cc: Johannes Weiner > Cc: Michal Hocko > Cc: Aneesh Kumar K.V Acked-by: Michal Hocko > --- > block/blk-cgroup.c | 3 ++- > include/linux/cgroup.h | 2 +- > kernel/cgroup.c | 7 ++++++- > mm/hugetlb_cgroup.c | 5 ++--- > mm/memcontrol.c | 3 ++- > net/ipv4/tcp_memcontrol.c | 2 +- > 6 files changed, 14 insertions(+), 8 deletions(-) > > diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c > index 5cfbc72..2541cf0 100644 > --- a/block/blk-cgroup.c > +++ b/block/blk-cgroup.c > @@ -1124,7 +1124,8 @@ int __init blkcg_policy_register(struct blkcg_policy *pol) > > /* everything is in place, add intf files for the new policy */ > if (pol->cftypes) > - WARN_ON(cgroup_add_cftypes(&blkio_cgrp_subsys, pol->cftypes)); > + WARN_ON(cgroup_add_legacy_cftypes(&blkio_cgrp_subsys, > + pol->cftypes)); > ret = 0; > out_unlock: > mutex_unlock(&blkcg_pol_mutex); > diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h > index a6e9c2e..f5f0fee 100644 > --- a/include/linux/cgroup.h > +++ b/include/linux/cgroup.h > @@ -590,7 +590,7 @@ static inline void pr_cont_cgroup_path(struct cgroup *cgrp) > > char *task_cgroup_path(struct task_struct *task, char *buf, size_t buflen); > > -int cgroup_add_cftypes(struct cgroup_subsys *ss, struct cftype *cfts); > +int cgroup_add_legacy_cftypes(struct cgroup_subsys *ss, struct cftype *cfts); > int cgroup_rm_cftypes(struct cftype *cfts); > > bool cgroup_is_descendant(struct cgroup *cgrp, struct cgroup *ancestor); > diff --git a/kernel/cgroup.c b/kernel/cgroup.c > index 6496a83..c275aa4 100644 > --- a/kernel/cgroup.c > +++ b/kernel/cgroup.c > @@ -3170,7 +3170,7 @@ int cgroup_rm_cftypes(struct cftype *cfts) > * function currently returns 0 as long as @cfts registration is successful > * even if some file creation attempts on existing cgroups fail. > */ > -int cgroup_add_cftypes(struct cgroup_subsys *ss, struct cftype *cfts) > +static int cgroup_add_cftypes(struct cgroup_subsys *ss, struct cftype *cfts) > { > int ret; > > @@ -3195,6 +3195,11 @@ int cgroup_add_cftypes(struct cgroup_subsys *ss, struct cftype *cfts) > return ret; > } > > +int cgroup_add_legacy_cftypes(struct cgroup_subsys *ss, struct cftype *cfts) > +{ > + return cgroup_add_cftypes(ss, cfts); > +} > + > /** > * cgroup_task_count - count the number of tasks in a cgroup. > * @cgrp: the cgroup in question > diff --git a/mm/hugetlb_cgroup.c b/mm/hugetlb_cgroup.c > index 493f758..9aae6f4 100644 > --- a/mm/hugetlb_cgroup.c > +++ b/mm/hugetlb_cgroup.c > @@ -358,9 +358,8 @@ static void __init __hugetlb_cgroup_file_init(int idx) > cft = &h->cgroup_files[4]; > memset(cft, 0, sizeof(*cft)); > > - WARN_ON(cgroup_add_cftypes(&hugetlb_cgrp_subsys, h->cgroup_files)); > - > - return; > + WARN_ON(cgroup_add_legacy_cftypes(&hugetlb_cgrp_subsys, > + h->cgroup_files)); > } > > void __init hugetlb_cgroup_file_init(void) > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index 8331f27..b6b3c6f 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -7065,7 +7065,8 @@ __setup("swapaccount=", enable_swap_account); > > static void __init memsw_file_init(void) > { > - WARN_ON(cgroup_add_cftypes(&memory_cgrp_subsys, memsw_cgroup_files)); > + WARN_ON(cgroup_add_legacy_cftypes(&memory_cgrp_subsys, > + memsw_cgroup_files)); > } > > static void __init enable_swap_cgroup(void) > diff --git a/net/ipv4/tcp_memcontrol.c b/net/ipv4/tcp_memcontrol.c > index f7a2ec3..3af5226 100644 > --- a/net/ipv4/tcp_memcontrol.c > +++ b/net/ipv4/tcp_memcontrol.c > @@ -222,7 +222,7 @@ static struct cftype tcp_files[] = { > > static int __init tcp_memcontrol_init(void) > { > - WARN_ON(cgroup_add_cftypes(&memory_cgrp_subsys, tcp_files)); > + WARN_ON(cgroup_add_legacy_cftypes(&memory_cgrp_subsys, tcp_files)); > return 0; > } > __initcall(tcp_memcontrol_init); > -- > 1.9.3 > -- Michal Hocko SUSE Labs -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/