From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: 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 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> In-Reply-To: <20180425154827.32251-1-hch@lst.de> References: <20180425154827.32251-1-hch@lst.de> Sender: linux-rtc-owner@vger.kernel.org List-ID: 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) -- 2.17.0