Messages in this thread Patch in this message | | | Date | Wed, 4 Jun 2008 01:40:59 -0700 | From | Andrew Morton <> | Subject | Re: [PATCH] proc: calculate the correct /proc/<pid> link count |
| |
On Tue, 3 Jun 2008 15:16:59 +0200 Vegard Nossum <vegard.nossum@gmail.com> wrote:
> From: Vegard Nossum <vegard.nossum@gmail.com> > Date: Mon, 2 Jun 2008 08:57:45 +0200 > Subject: [PATCH] proc: calculate the correct /proc/<pid> link count > > commit e9720acd728a46cb40daa52c99a979f7c4ff195c
Linus gets upset when we refer to commits only by their hash.
I did this:
This patch:
commit e9720acd728a46cb40daa52c99a979f7c4ff195c Author: Pavel Emelyanov <xemul@openvz.org> Date: Fri Mar 7 11:08:40 2008 -0800
[NET]: Make /proc/net a symlink on /proc/self/net (v3)
introduced a /proc/self/net directory without bumping the corresponding link count for /proc/self.
> introduced a > /proc/self/net directory without bumping the corresponding link count > for /proc/self. > > This patch replaces the static link count initializations with a call > that counts the number of directory entries in the given pid_entry > table whenever it is instantiated, and thus relieves the burden of > manually keeping the two in sync.
Seems much saner.
> diff --git a/fs/proc/base.c b/fs/proc/base.c > index c447e07..334ce46 100644 > --- a/fs/proc/base.c > +++ b/fs/proc/base.c > @@ -127,6 +127,23 @@ struct pid_entry { > NULL, &proc_single_file_operations, \ > { .proc_show = &proc_##OTYPE } ) > > +/* Count the number of hardlinks for the pid_entry table, excluding the . > + * and .. links. */
Like this:
/* * Count the number of hardlinks for the pid_entry table, excluding the . * and .. links. */
please.
> +static unsigned int pid_entry_count_dirs(const struct pid_entry *entries, > + unsigned int n) > +{ > + unsigned int i; > + unsigned int count; > + > + count = 0; > + for (i = 0; i < n; ++i) { > + if (S_ISDIR(entries[i].mode)) > + ++count; > + } > + > + return count; > +}
I'm unable to correlate the code with the comment. There is nothing in here which handles . and ..?
> @@ -2585,10 +2602,9 @@ static struct dentry *proc_pid_instantiate(struct inode *dir, > inode->i_op = &proc_tgid_base_inode_operations; > inode->i_fop = &proc_tgid_base_operations; > inode->i_flags|=S_IMMUTABLE; > - inode->i_nlink = 5; > -#ifdef CONFIG_SECURITY > - inode->i_nlink += 1; > -#endif > + > + inode->i_nlink = 2 + pid_entry_count_dirs(tgid_base_stuff, > + ARRAY_SIZE(tgid_base_stuff)); >
oh, can we do that? Is it possible for some code somewhere to come along and add a new entry to /proc/pid which doesn't appear in these static tables?
I guess that doesn't happen. In which case can we not calculate the unmber of directories in these two tables just a single time, at bootup?
I think I'm missing things here...
| |