From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751590AbWBWQLv (ORCPT ); Thu, 23 Feb 2006 11:11:51 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751594AbWBWQLv (ORCPT ); Thu, 23 Feb 2006 11:11:51 -0500 Received: from ebiederm.dsl.xmission.com ([166.70.28.69]:10135 "EHLO ebiederm.dsl.xmission.com") by vger.kernel.org with ESMTP id S1751587AbWBWQLu (ORCPT ); Thu, 23 Feb 2006 11:11:50 -0500 To: Andrew Morton Cc: Subject: [PATCH 10/23] proc: Fix the link count for /proc//task References:

From: ebiederm@xmission.com (Eric W. Biederman) Date: Thu, 23 Feb 2006 09:10:41 -0700 In-Reply-To: (Eric W. Biederman's message of "Thu, 23 Feb 2006 09:08:20 -0700") Message-ID: User-Agent: Gnus/5.1007 (Gnus v5.10.7) Emacs/21.4 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Use getattr to get an accurate link count when needed. This is cheaper and more accurate than trying to derive it by walking the thread list of a process. Signed-off-by: Eric W. Biederman --- fs/proc/base.c | 21 +++++++++++++++++++-- 1 files changed, 19 insertions(+), 2 deletions(-) eec5c7327c53b862025a595985a72fa01509c5e4 diff --git a/fs/proc/base.c b/fs/proc/base.c index 81c2f2a..1a39258 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -1466,6 +1466,7 @@ out: static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir); static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd); +static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat); static struct file_operations proc_fd_operations = { .read = generic_read_dir, @@ -1486,6 +1487,7 @@ static struct inode_operations proc_fd_i static struct inode_operations proc_task_inode_operations = { .lookup = proc_task_lookup, + .getattr = proc_task_getattr, }; #ifdef CONFIG_SECURITY @@ -1592,7 +1594,7 @@ static struct dentry *proc_pident_lookup */ switch(p->type) { case PROC_TGID_TASK: - inode->i_nlink = 2 + get_tid_list(2, NULL, dir); + inode->i_nlink = 2; inode->i_op = &proc_task_inode_operations; inode->i_fop = &proc_task_operations; break; @@ -2189,7 +2191,6 @@ static int proc_task_readdir(struct file } nr_tids = get_tid_list(pos, tid_array, inode); - inode->i_nlink = pos + nr_tids; for (i = 0; i < nr_tids; i++) { unsigned long j = PROC_NUMBUF; @@ -2209,3 +2210,19 @@ out: filp->f_pos = pos; return retval; } + +static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) +{ + struct inode *inode = dentry->d_inode; + struct task_struct *p = proc_task(inode); + generic_fillattr(inode, stat); + + if (pid_alive(p)) { + task_lock(p); + if (p->signal) + stat->nlink += atomic_read(&p->signal->count); + task_unlock(p); + } + + return 0; +} -- 1.2.2.g709a