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From: ebiederm@xmission.com (Eric W. Biederman)
To: Andrew Morton <akpm@osdl.org>
Cc: <linux-kernel@vger.kernel.org>
Subject: [PATCH 10/23] proc: Fix the link count for /proc/<pid>/task
Date: Thu, 23 Feb 2006 09:10:41 -0700	[thread overview]
Message-ID: <m1d5heginy.fsf_-_@ebiederm.dsl.xmission.com> (raw)
In-Reply-To: <m1hd6qgirv.fsf_-_@ebiederm.dsl.xmission.com> (Eric W. Biederman's message of "Thu, 23 Feb 2006 09:08:20 -0700")


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 <ebiederm@xmission.com>


---

 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


  reply	other threads:[~2006-02-23 16:11 UTC|newest]

Thread overview: 49+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-02-23 15:52 [PATCH 00/23] proc cleanup Eric W. Biederman
2006-02-23 15:54 ` [PATCH 01/23] tref: Implement task references Eric W. Biederman
2006-02-23 15:56   ` [PATCH 02/23] proc: Fix the .. inode number on /proc/<pid>/fd Eric W. Biederman
2006-02-23 15:57     ` [PATCH 03/23] proc: Remove useless BKL in proc_pid_readlink Eric W. Biederman
2006-02-23 15:58       ` [PATCH 04/23] proc: Remove unnecessary and misleading assignments from proc_pid_make_inode Eric W. Biederman
2006-02-23 16:00         ` [PATCH 05/23] proc: Simplify the ownership rules for /proc Eric W. Biederman
2006-02-23 16:02           ` Eric W. Biederman
2006-02-23 16:04           ` [PATCH 06/23] proc: Replace proc_inode.type with proc_inode.fd Eric W. Biederman
2006-02-23 16:05             ` [PATCH 07/23] proc: Remove bogus proc_task_permission Eric W. Biederman
2006-02-23 16:06               ` [PATCH 08/23] proc: Kill proc_mem_inode_operations Eric W. Biederman
2006-02-23 16:08                 ` [PATCH 09/23] proc: Properly filter out files that are not visible to a process Eric W. Biederman
2006-02-23 16:10                   ` Eric W. Biederman [this message]
2006-02-23 16:12                     ` [PATCH 11/23] proc: Move proc_maps_operations into task_mmu.c Eric W. Biederman
2006-02-23 16:15                       ` [PATCH 12/23] proc: Rewrite the proc dentry flush on exit optimization Eric W. Biederman
2006-02-23 16:16                         ` [PATCH 13/23] proc: Close the race of a process dying durning lookup Eric W. Biederman
2006-02-23 16:18                           ` [PATCH 14/23] proc: Make PROC_NUMBUF the buffer size for holding a integers as strings Eric W. Biederman
2006-02-23 16:20                             ` [PATCH 15/23] proc: refactor reading directories of tasks Eric W. Biederman
2006-02-23 16:23                               ` [PATCH 16/23] proc: Don't lock task_structs indefinitely Eric W. Biederman
2006-02-23 16:24                                 ` [PATCH 17/23] proc: Give the root directory a task Eric W. Biederman
2006-02-23 16:25                                   ` [PATCH 18/23] proc: Reorder the functions in base.c Eric W. Biederman
2006-02-23 16:27                                     ` [PATCH 19/23] proc: Modify proc_pident_lookup to be completely table driven Eric W. Biederman
2006-02-23 16:28                                       ` [PATCH 20/23] proc: Make the generation of the self symlink " Eric W. Biederman
2006-02-23 16:30                                         ` [PATCH 21/23] proc: Factor out an instantiate method from every lookup method Eric W. Biederman
2006-02-23 16:32                                           ` [PATCH 22/23] proc: Remove the hard coded inode numbers Eric W. Biederman
2006-02-23 16:34                                             ` [PATCH 23/23] proc: Merge proc_tid_attr and proc_tgid_attr Eric W. Biederman
2006-02-23 16:49   ` [PATCH 01/23] tref: Implement task references Eric W. Biederman
2006-03-02 19:16     ` Oleg Nesterov
2006-03-02 20:37       ` Oleg Nesterov
2006-03-02 22:19       ` Eric W. Biederman
2006-03-03 16:56         ` Oleg Nesterov
2006-03-03 17:48           ` Eric W. Biederman
2006-03-04 11:16           ` Eric W. Biederman
2006-03-04 12:31             ` Oleg Nesterov
2006-03-04 17:30               ` Oleg Nesterov
2006-03-06 21:06         ` Oleg Nesterov
2006-03-06 22:18           ` Eric W. Biederman
2006-03-07 20:44             ` Oleg Nesterov
2006-03-07  1:39           ` Eric W. Biederman
2006-03-07 20:38             ` Oleg Nesterov
2006-03-07 13:12           ` Eric W. Biederman
2006-03-07 21:02             ` Oleg Nesterov
2006-03-07 23:00               ` Eric W. Biederman
2006-03-03 19:23     ` Oleg Nesterov
2006-03-04 10:51       ` Eric W. Biederman
2006-02-25 12:27 ` [PATCH 00/23] proc cleanup Andrew Morton
2006-02-25 13:34   ` Eric W. Biederman
2006-02-25 15:20   ` Eric W. Biederman
2006-02-27 15:26 ` Serge E. Hallyn
2006-02-27 15:56   ` Eric W. Biederman

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