From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756689AbcH3P5r (ORCPT ); Tue, 30 Aug 2016 11:57:47 -0400 Received: from mail-qk0-f195.google.com ([209.85.220.195]:35068 "EHLO mail-qk0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755955AbcH3P5q (ORCPT ); Tue, 30 Aug 2016 11:57:46 -0400 Date: Tue, 30 Aug 2016 11:57:42 -0400 From: Tejun Heo To: Linus Torvalds Cc: Li Zefan , Johannes Weiner , cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Balbir Singh Subject: [GIT PULL] cgroup fixes for v4.8-rc4 Message-ID: <20160830155742.GA12660@htj.duckdns.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.7.0 (2016-08-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, Linus. Two fixes for cgroup. * There still was a hole in enforcing cpuset rules, fixed by Li. * Recent switch to global percpu_rwseom for threadgroup locking revealed a couple issues in how percpu_rwsem is implemented and used by cgroup. Balbir found that the read locking section was too wide unnecessarily including operations which can often depend on IOs. With percpu_rwsem updates (coming through a different tree) and reduction of read locking section, all the reported locking latency issues, including the android one, are resolved. It looks like we can keep global percpu_rwsem locking for now. If there actually are cases which can't be resolved, we can go back to more complex per-signal_struct locking. Thanks. The following changes since commit 29b4817d4018df78086157ea3a55c1d9424a7cfc: Linux 4.8-rc1 (2016-08-07 18:18:00 -0700) are available in the git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup.git for-4.8-fixes for you to fetch changes up to 568ac888215c7fb2fabe8ea739b00ec3c1f5d440: cgroup: reduce read locked section of cgroup_threadgroup_rwsem during fork (2016-08-17 09:54:52 -0400) ---------------------------------------------------------------- Balbir Singh (1): cgroup: reduce read locked section of cgroup_threadgroup_rwsem during fork Zefan Li (1): cpuset: make sure new tasks conform to the current config of the cpuset kernel/cpuset.c | 15 +++++++++++++++ kernel/fork.c | 4 ++-- 2 files changed, 17 insertions(+), 2 deletions(-) -- tejun