Re: [PATCHv2 0/2] remap_file_pages() decommission

["Kirill A. Shutemov" <kirill@shutemov.name>]

On Fri, May 09, 2014 at 08:14:08AM -0700, Linus Torvalds wrote:
> On Fri, May 9, 2014 at 7:05 AM, Kirill A. Shutemov
> <kirill.shutemov@linux.intel.com> wrote:
> >
> > Hm. I'm confused here. Do we have any limit forced per-user?
> 
> Sure we do. See "struct user_struct". We limit max number of
> processes, open files, signals etc.

Okay got it.

BTW, nobody seems use field 'files' of user_struct:

>From 8bb8a0c740ad66126be4d3c092493e1ecc2189ef Mon Sep 17 00:00:00 2001
From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Date: Fri, 9 May 2014 20:25:55 +0300
Subject: [PATCH] kernel: drop unused field 'files' from user_struct

Nobody seems uses it for a long time. Let's drop it.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
---
 include/linux/sched.h | 1 -
 kernel/user.c         | 1 -
 2 files changed, 2 deletions(-)

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 25f54c79f757..f0503ffa7a59 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -745,7 +745,6 @@ static inline int signal_group_exit(const struct signal_struct *sig)
 struct user_struct {
 	atomic_t __count;	/* reference count */
 	atomic_t processes;	/* How many processes does this user have? */
-	atomic_t files;		/* How many open files does this user have? */
 	atomic_t sigpending;	/* How many pending signals does this user have? */
 #ifdef CONFIG_INOTIFY_USER
 	atomic_t inotify_watches; /* How many inotify watches does this user have? */
diff --git a/kernel/user.c b/kernel/user.c
index 294fc6a94168..4efa39350e44 100644
--- a/kernel/user.c
+++ b/kernel/user.c
@@ -87,7 +87,6 @@ static DEFINE_SPINLOCK(uidhash_lock);
 struct user_struct root_user = {
 	.__count	= ATOMIC_INIT(1),
 	.processes	= ATOMIC_INIT(1),
-	.files		= ATOMIC_INIT(0),
 	.sigpending	= ATOMIC_INIT(0),
 	.locked_shm     = 0,
 	.uid		= GLOBAL_ROOT_UID,
-- 
 Kirill A. Shutemov