From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH] cgroup.c: Use built-in RCU list checking Date: Wed, 12 Feb 2020 17:12:49 -0500 Message-ID: <20200212221249.GJ80993@mtj.thefacebook.com> References: <20200118031051.28776-1-madhuparnabhowmik10@gmail.com> Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=htZSNJ3oIZAPreJh5xh8HpLPmxowkMMDY5AHwsIFPU4=; b=JgbLnHXZBEJ6fny9Cf39uzWywqhTZCEc9XA7HjonBYcbbBVxey3E8jGB1bPKWVrUdH MDi2aKPGMfYktEAwxum6w8vAcuQKbRKfvpUwLIGwLk3/YmeHtcygHekDiNYf5+9Q3/ti zacH6LhE208pGea8c9ESgsdYtAeXB4ezKvDfBqcv9jlPHtgoFYltXKi/V/yrcVbYwnku X3bNAPwE8YMLtOxeeS52qw2JNI4UFj3sP6w3f4vVctpZ6uj6fLe0Dq1xLddiXOyyjYKa A7dAQszw4h0EP/fqdq1NQXGkBCDWNQkAIM2qeUiWaw6Udu9cErLrvXzo/wABUaU4uD/W FynQ== Content-Disposition: inline In-Reply-To: <20200118031051.28776-1-madhuparnabhowmik10@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: madhuparnabhowmik10@gmail.com Cc: lizefan@huawei.com, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, joel@joelfernandes.org, rcu@vger.kernel.org, frextrite@gmail.com On Sat, Jan 18, 2020 at 08:40:51AM +0530, madhuparnabhowmik10@gmail.com wrote: > From: Madhuparna Bhowmik > > list_for_each_entry_rcu has built-in RCU and lock checking. > Pass cond argument to list_for_each_entry_rcu() to silence > false lockdep warning when CONFIG_PROVE_RCU_LIST is enabled > by default. > > Even though the function css_next_child() already checks if > cgroup_mutex or rcu_read_lock() is held using > cgroup_assert_mutex_or_rcu_locked(), there is a need to pass > cond to list_for_each_entry_rcu() to avoid false positive > lockdep warning. > > Signed-off-by: Madhuparna Bhowmik Applied to cgroup/for-5.7. Thanks. -- tejun