From patchwork Wed Apr 25 15:47:58 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 10363805 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id B60946032C for ; Wed, 25 Apr 2018 16:19:35 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A088A28C56 for ; Wed, 25 Apr 2018 16:19:35 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 92EE528C87; Wed, 25 Apr 2018 16:19:35 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI, T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 377E128C56 for ; Wed, 25 Apr 2018 16:19:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932077AbeDYQSH (ORCPT ); Wed, 25 Apr 2018 12:18:07 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:38586 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754838AbeDYPuN (ORCPT ); Wed, 25 Apr 2018 11:50:13 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=References:In-Reply-To:Message-Id: Date:Subject:Cc:To:From:Sender:Reply-To:MIME-Version:Content-Type: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=Nr/fMNa2EYIfUJMtZ3v5wAxQojen7+SQUINM1QCPTpU=; b=aLOiOIrv4aN8eIYMwpU3V2UkX OomGeBgXz2lIXQdycEJaoO560/UR5UG034l3Rth0uyeY46PSCChYHysosnc6P8QaGRb0/yjKBCLUe byt+UVUkp5txrXTi/BLo6PcbO3aTioGRBhOZBP/99E26xI1aVYa8IDrKNHtZpEJ/x0cNJVOyFpp8w BXL9VywDCw7k4ylWSEnn/4k4/nXQAROqwlhLWRTTTjBoTOyTIkmA0WXApsU0GaMPeyHRsWF2lGWcJ 2a0QCbTzP5Yhi/aJwkvD/vMako4gWIW3CGExnCkL/05EJPWz/q/ijGkR3B3zNugYyop0pn+ql44hb VzkXE6Hyg==; Received: from 089144200182.atnat0009.highway.a1.net ([89.144.200.182] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1fBMfa-0001d3-UY; Wed, 25 Apr 2018 15:49:23 +0000 From: Christoph Hellwig To: Andrew Morton , Alexander Viro Cc: Alexey Dobriyan , Greg Kroah-Hartman , Jiri Slaby , Alessandro Zummo , Alexandre Belloni , linux-acpi@vger.kernel.org, drbd-dev@lists.linbit.com, linux-ide@vger.kernel.org, netdev@vger.kernel.org, linux-rtc@vger.kernel.org, megaraidlinux.pdl@broadcom.com, linux-scsi@vger.kernel.org, devel@driverdev.osuosl.org, linux-afs@lists.infradead.org, linux-ext4@vger.kernel.org, jfs-discussion@lists.sourceforge.net, netfilter-devel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 11/40] ipv6/flowlabel: simplify pid namespace lookup Date: Wed, 25 Apr 2018 17:47:58 +0200 Message-Id: <20180425154827.32251-12-hch@lst.de> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180425154827.32251-1-hch@lst.de> References: <20180425154827.32251-1-hch@lst.de> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The shole seq_file sequence already operates under a single RCU lock pair, so move the pid namespace lookup into it, and stop grabbing a reference and remove all kinds of boilerplate code. Signed-off-by: Christoph Hellwig --- net/ipv6/ip6_flowlabel.c | 28 +++++----------------------- 1 file changed, 5 insertions(+), 23 deletions(-) diff --git a/net/ipv6/ip6_flowlabel.c b/net/ipv6/ip6_flowlabel.c index c05c4e82a7ca..a9f221d45ef9 100644 --- a/net/ipv6/ip6_flowlabel.c +++ b/net/ipv6/ip6_flowlabel.c @@ -754,7 +754,10 @@ static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos) static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos) __acquires(RCU) { + struct ip6fl_iter_state *state = ip6fl_seq_private(seq); + rcu_read_lock_bh(); + state->pid_ns = task_active_pid_ns(current); return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; } @@ -810,36 +813,15 @@ static const struct seq_operations ip6fl_seq_ops = { static int ip6fl_seq_open(struct inode *inode, struct file *file) { - struct seq_file *seq; - struct ip6fl_iter_state *state; - int err; - - err = seq_open_net(inode, file, &ip6fl_seq_ops, + return seq_open_net(inode, file, &ip6fl_seq_ops, sizeof(struct ip6fl_iter_state)); - - if (!err) { - seq = file->private_data; - state = ip6fl_seq_private(seq); - rcu_read_lock(); - state->pid_ns = get_pid_ns(task_active_pid_ns(current)); - rcu_read_unlock(); - } - return err; -} - -static int ip6fl_seq_release(struct inode *inode, struct file *file) -{ - struct seq_file *seq = file->private_data; - struct ip6fl_iter_state *state = ip6fl_seq_private(seq); - put_pid_ns(state->pid_ns); - return seq_release_net(inode, file); } static const struct file_operations ip6fl_seq_fops = { .open = ip6fl_seq_open, .read = seq_read, .llseek = seq_lseek, - .release = ip6fl_seq_release, + .release = seq_release_net, }; static int __net_init ip6_flowlabel_proc_init(struct net *net)