From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCHSET] cgroup: simplify cgroup removal path Date: Wed, 31 Oct 2012 10:18:49 -0700 Message-ID: <20121031171849.GH2945@htj.dyndns.org> References: <1351657365-25055-1-git-send-email-tj@kernel.org> <50912C6D.6020000@parallels.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; bh=rVv/mV7MmEM1fmUkAHHp+CO5mcoM9yJBFRMIa1FJP5w=; b=tlGpJbHihDq/SfevD10dmgGdgr02PIO48SkVKHylncEgblchAg79lkqdYF64eqBrjz yTJc+Z0ccr+7djoLEjdqqB/Xk3n39zVKBCmFfMvXew9VreP4n2eF+tvg0qLR/jdPlcBl s2csRJ6aZ6uwB8dDojcScTqYFRRZMJbk7y96d//fKSYcoP3Iqt7y7CebVpGtxGkxkdDV R8m4B3xGIsgvMSpKdJCGK8E4lReAt5EF5HFw4RHRbxNNWXEnc2nSDJpAobfspwE0YGOm +Qy7CpDCjUovuseiy8T/KYPTJH7x597Kc1jw+czBy+Bh+13IMNoL0EhFrLkHUbunYccY jiTQ== Content-Disposition: inline In-Reply-To: <50912C6D.6020000-bzQdu9zFT3WakBO8gow8eQ@public.gmane.org> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Glauber Costa Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, mhocko-AlSwsSmVLrQ@public.gmane.org, hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Hello, On Wed, Oct 31, 2012 at 05:49:33PM +0400, Glauber Costa wrote: > The only think that drew my attention is that you are changing the > local_irq_save callsite to local_irq_disable. It shouldn't be a problem, > since this is never expected to be called in interrupt context. > > Still... it makes me wonder if that disabled-interrupt block is still > needed? According to the changelogs, it was introduced in e7c5ec919 for > the css_tryget mechanism. But css_tryget itself will never scan > subsystems, so if we can no longer fail, we should be able to just ditch > it. Unless I am missing something Note both in the commit messages. Thanks. -- tejun From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758358Ab2JaRSz (ORCPT ); Wed, 31 Oct 2012 13:18:55 -0400 Received: from mail-pa0-f46.google.com ([209.85.220.46]:35586 "EHLO mail-pa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751956Ab2JaRSx (ORCPT ); Wed, 31 Oct 2012 13:18:53 -0400 Date: Wed, 31 Oct 2012 10:18:49 -0700 From: Tejun Heo To: Glauber Costa Cc: lizefan@huawei.com, hannes@cmpxchg.org, mhocko@suse.cz, bsingharora@gmail.com, kamezawa.hiroyu@jp.fujitsu.com, containers@lists.linux-foundation.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCHSET] cgroup: simplify cgroup removal path Message-ID: <20121031171849.GH2945@htj.dyndns.org> References: <1351657365-25055-1-git-send-email-tj@kernel.org> <50912C6D.6020000@parallels.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <50912C6D.6020000@parallels.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Wed, Oct 31, 2012 at 05:49:33PM +0400, Glauber Costa wrote: > The only think that drew my attention is that you are changing the > local_irq_save callsite to local_irq_disable. It shouldn't be a problem, > since this is never expected to be called in interrupt context. > > Still... it makes me wonder if that disabled-interrupt block is still > needed? According to the changelogs, it was introduced in e7c5ec919 for > the css_tryget mechanism. But css_tryget itself will never scan > subsystems, so if we can no longer fail, we should be able to just ditch > it. Unless I am missing something Note both in the commit messages. Thanks. -- tejun