From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757845Ab1GKOQe (ORCPT ); Mon, 11 Jul 2011 10:16:34 -0400 Received: from mail-vx0-f174.google.com ([209.85.220.174]:51078 "EHLO mail-vx0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757735Ab1GKOPV (ORCPT ); Mon, 11 Jul 2011 10:15:21 -0400 From: Frederic Weisbecker To: LKML Cc: Frederic Weisbecker , Andrew Morton , Paul Menage , Li Zefan , Johannes Weiner , Aditya Kali Subject: [PATCH 2/7] cgroups: New resource counter inheritance API Date: Mon, 11 Jul 2011 16:15:01 +0200 Message-Id: <1310393706-321-3-git-send-email-fweisbec@gmail.com> X-Mailer: git-send-email 1.7.5.4 In-Reply-To: <1310393706-321-1-git-send-email-fweisbec@gmail.com> References: <1310393706-321-1-git-send-email-fweisbec@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Provide an API to inherit a counter value from a parent. This can be useful to implement cgroup.clone_children on a resource counter. Still the resources of the children are limited by those of the parent, so this is only to provide a default setting behaviour when clone_children is set. Signed-off-by: Frederic Weisbecker Cc: Paul Menage Cc: Li Zefan Cc: Johannes Weiner Cc: Aditya Kali --- include/linux/res_counter.h | 2 ++ kernel/res_counter.c | 25 +++++++++++++++++++++++++ 2 files changed, 27 insertions(+), 0 deletions(-) diff --git a/include/linux/res_counter.h b/include/linux/res_counter.h index 1b3fe05..109d118 100644 --- a/include/linux/res_counter.h +++ b/include/linux/res_counter.h @@ -84,6 +84,8 @@ int res_counter_write(struct res_counter *counter, int member, void res_counter_write_u64(struct res_counter *counter, int member, u64 val); +void res_counter_inherit(struct res_counter *counter, int member); + /* * the field descriptors. one for each member of res_counter */ diff --git a/kernel/res_counter.c b/kernel/res_counter.c index 806d041..8cb0362 100644 --- a/kernel/res_counter.c +++ b/kernel/res_counter.c @@ -198,3 +198,28 @@ int res_counter_write(struct res_counter *counter, int member, return 0; } + +void res_counter_inherit(struct res_counter *counter, int member) +{ + struct res_counter *parent; + unsigned long long *pval, val; + unsigned long flags; + + parent = counter->parent; + if (!parent) + return; + + local_irq_save(flags); + + spin_lock(&counter->lock); + pval = res_counter_member(counter, member); + val = *pval; + spin_unlock(&counter->lock); + + spin_lock(&parent->lock); + pval = res_counter_member(parent, member); + *pval = val; + spin_unlock(&parent->lock); + + local_irq_restore(flags); +} -- 1.7.5.4