From patchwork Mon Mar 23 04:54:18 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tejun Heo X-Patchwork-Id: 6070311 Return-Path: X-Original-To: patchwork-linux-fsdevel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id D654F9F318 for ; Mon, 23 Mar 2015 05:18:49 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 0AAFE201FA for ; Mon, 23 Mar 2015 05:18:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3A835200E7 for ; Mon, 23 Mar 2015 05:18:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752189AbbCWEz1 (ORCPT ); Mon, 23 Mar 2015 00:55:27 -0400 Received: from mail-qc0-f169.google.com ([209.85.216.169]:35368 "EHLO mail-qc0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751465AbbCWEzU (ORCPT ); Mon, 23 Mar 2015 00:55:20 -0400 Received: by qcbkw5 with SMTP id kw5so136820863qcb.2; Sun, 22 Mar 2015 21:55:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references; bh=6QhiKnG6awNOOoUyM/l2PLv1fwkjCAIuOPIXvUwqjBQ=; b=txlTzYWhgQ2rQfuMO4N4ZhR3fUre0G/uOibwyd2szu6WaZrZPeu1InQ0fIsl+Bss8c PjIL/sSHshypWNcFGZDnZZ2evApD28mEb1dBif26CdJGdmhI0yAFcHeBvB6r8fikWTWt SH8l4boBG/F+m4uESEkHSsXCdiOkSXyCpxGxFj58+yKDVSGmnvjdx/aaDD2X+Kpod1Ua UXRn97aUqXxzuXHM+z20oInP6EBuEj6UUBjew8su3lN17/MgX/CcwyA5ewrczFNq0qlr kL/3/89ULm057KrDB+oS6uFqWs38TvYhHdtu19jb1ZeY0bTM3ehUGtHbnqhXf8tcdnaN j/wA== X-Received: by 10.229.26.69 with SMTP id d5mr115974981qcc.9.1427086519965; Sun, 22 Mar 2015 21:55:19 -0700 (PDT) Received: from htj.duckdns.org.lan (207-38-238-8.c3-0.wsd-ubr1.qens-wsd.ny.cable.rcn.com. [207.38.238.8]) by mx.google.com with ESMTPSA id n20sm8504159qgd.48.2015.03.22.21.55.18 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 22 Mar 2015 21:55:19 -0700 (PDT) From: Tejun Heo To: axboe@kernel.dk Cc: linux-kernel@vger.kernel.org, jack@suse.cz, hch@infradead.org, hannes@cmpxchg.org, linux-fsdevel@vger.kernel.org, vgoyal@redhat.com, lizefan@huawei.com, cgroups@vger.kernel.org, linux-mm@kvack.org, mhocko@suse.cz, clm@fb.com, fengguang.wu@intel.com, david@fromorbit.com, gthelen@google.com, Tejun Heo Subject: [PATCH 07/48] blkcg: implement task_get_blkcg_css() Date: Mon, 23 Mar 2015 00:54:18 -0400 Message-Id: <1427086499-15657-8-git-send-email-tj@kernel.org> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1427086499-15657-1-git-send-email-tj@kernel.org> References: <1427086499-15657-1-git-send-email-tj@kernel.org> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Spam-Status: No, score=-6.8 required=5.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID,T_RP_MATCHES_RCVD,UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Implement a wrapper around task_get_css() to acquire the blkcg css for a given task. The wrapper is necessary for cgroup writeback support as there will be places outside blkcg proper trying to acquire blkcg_css and blkio_cgrp_id will be undefined when !CONFIG_BLK_CGROUP. Signed-off-by: Tejun Heo --- include/linux/blk-cgroup.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h index 65f0c17..4dc643f 100644 --- a/include/linux/blk-cgroup.h +++ b/include/linux/blk-cgroup.h @@ -195,6 +195,12 @@ static inline struct blkcg *bio_blkcg(struct bio *bio) return task_blkcg(current); } +static inline struct cgroup_subsys_state * +task_get_blkcg_css(struct task_struct *task) +{ + return task_get_css(task, blkio_cgrp_id); +} + /** * blkcg_parent - get the parent of a blkcg * @blkcg: blkcg of interest @@ -573,6 +579,12 @@ struct blkcg_policy { #define blkcg_root_css ((struct cgroup_subsys_state *)ERR_PTR(-EINVAL)) +static inline struct cgroup_subsys_state * +task_get_blkcg_css(struct task_struct *task) +{ + return NULL; +} + #ifdef CONFIG_BLOCK static inline struct blkcg_gq *blkg_lookup(struct blkcg *blkcg, void *key) { return NULL; }