From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754208AbaDRTNl (ORCPT ); Fri, 18 Apr 2014 15:13:41 -0400 Received: from mx1.redhat.com ([209.132.183.28]:45483 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752189AbaDRTNS (ORCPT ); Fri, 18 Apr 2014 15:13:18 -0400 Date: Fri, 18 Apr 2014 21:12:59 +0200 From: Oleg Nesterov To: Andrew Morton , Michal Hocko Cc: Peter Chiang , KAMEZAWA Hiroyuki , Balbir Singh , Johannes Weiner , "ccross@android.com" , "lizefan@huawei.com" , "tj@kernel.org" , "pavel@ucw.cz" , "ebiederm@xmission.com" , "guillaume@morinfr.org" , "linux-kernel@vger.kernel.org" Subject: [PATCH 0/1] memcg: kill start_kernel()->mm_init_owner(init_mm) Message-ID: <20140418191259.GA7413@redhat.com> References: <1397617379-26895-1-git-send-email-pchiang@nvidia.com> <80341664FB79C2419999599F48F738410227327881@HKMAIL01.nvidia.com> <80341664FB79C2419999599F48F738410227327888@HKMAIL01.nvidia.com> <20140416135741.GA9407@redhat.com> <80341664FB79C2419999599F48F7384102273279C3@HKMAIL01.nvidia.com> <20140418162359.GA4398@redhat.com> <20140418172631.GA13323@redhat.com> <20140418182444.GB22235@dhcp22.suse.cz> <20140418184441.GA26046@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140418184441.GA26046@redhat.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/18, Oleg Nesterov wrote: > > OTOH, mm->owner is used by mm/memcontrol.c, so perhaps the prefix is fine? > > I do not even understand why do we have CONFIG_MM_OWNER, perhaps it should > die? Seriously what do you think about the patch below? Afaics CONFIG_MM_OWNER is pointless. And I just noticed start_kernel()->mm_init_owner(). It looks simply wrong even if this is harmless, or I missed something? Could you review 1/1 as well? Oleg. --- diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 8967e20..de16272 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -406,7 +406,7 @@ struct mm_struct { spinlock_t ioctx_lock; struct kioctx_table __rcu *ioctx_table; #endif -#ifdef CONFIG_MM_OWNER +#ifdef CONFIG_MEMCG /* * "owner" points to a task that is regarded as the canonical * user/owner of this mm. All of the following must be true in diff --git a/include/linux/sched.h b/include/linux/sched.h index 82fe3da..570a325 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -2947,7 +2947,7 @@ static inline void inc_syscw(struct task_struct *tsk) #define TASK_SIZE_OF(tsk) TASK_SIZE #endif -#ifdef CONFIG_MM_OWNER +#ifdef CONFIG_MEMCG extern void mm_update_next_owner(struct mm_struct *mm); extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p); #else @@ -2958,7 +2958,7 @@ static inline void mm_update_next_owner(struct mm_struct *mm) static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p) { } -#endif /* CONFIG_MM_OWNER */ +#endif /* CONFIG_MEMCG */ static inline unsigned long task_rlimit(const struct task_struct *tsk, unsigned int limit) diff --git a/init/Kconfig b/init/Kconfig index 765018c..143119e 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -933,7 +933,6 @@ config RESOURCE_COUNTERS config MEMCG bool "Memory Resource Controller for Control Groups" depends on RESOURCE_COUNTERS - select MM_OWNER select EVENTFD help Provides a memory resource controller that manages both anonymous @@ -951,9 +950,6 @@ config MEMCG disable memory resource controller and you can avoid overheads. (and lose benefits of memory resource controller) - This config option also selects MM_OWNER config option, which - could in turn add some fork/exit overhead. - config MEMCG_SWAP bool "Memory Resource Controller Swap Extension" depends on MEMCG && SWAP @@ -1173,9 +1169,6 @@ config SCHED_AUTOGROUP desktop applications. Task group autogeneration is currently based upon task session. -config MM_OWNER - bool - config SYSFS_DEPRECATED bool "Enable deprecated sysfs features to support old userspace tools" depends on SYSFS diff --git a/kernel/exit.c b/kernel/exit.c index 429659c..e5c4668 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -313,7 +313,7 @@ kill_orphaned_pgrp(struct task_struct *tsk, struct task_struct *parent) } } -#ifdef CONFIG_MM_OWNER +#ifdef CONFIG_MEMCG /* * A task is exiting. If it owned this mm, find a new owner for the mm. */ @@ -399,7 +399,7 @@ assign_new_owner: task_unlock(c); put_task_struct(c); } -#endif /* CONFIG_MM_OWNER */ +#endif /* CONFIG_MEMCG */ /* * Turn us into a lazy TLB process if we diff --git a/kernel/fork.c b/kernel/fork.c index 54a8d26..ed75cf5 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1099,12 +1099,12 @@ static void rt_mutex_init_task(struct task_struct *p) #endif } -#ifdef CONFIG_MM_OWNER +#ifdef CONFIG_MEMCG void mm_init_owner(struct mm_struct *mm, struct task_struct *p) { mm->owner = p; } -#endif /* CONFIG_MM_OWNER */ +#endif /* CONFIG_MEMCG */ /* * Initialize POSIX timer handling for a single task.