From: Thomas Gleixner <tglx@linutronix.de>
Date: Tue, 21 Jul 2009 23:06:05 +0200
Subject: core: Do not disable interrupts on RT in kernel/users.c

Use the local_irq_*_nort variants to reduce latencies in RT. The code
is serialized by the locks. No need to disable interrupts.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

---
 kernel/user.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Index: linux-stable/kernel/user.c
===================================================================
--- linux-stable.orig/kernel/user.c
+++ linux-stable/kernel/user.c
@@ -147,11 +147,11 @@ void free_uid(struct user_struct *up)
 	if (!up)
 		return;
 
-	local_irq_save(flags);
+	local_irq_save_nort(flags);
 	if (atomic_dec_and_lock(&up->__count, &uidhash_lock))
 		free_user(up, flags);
 	else
-		local_irq_restore(flags);
+		local_irq_restore_nort(flags);
 }
 
 struct user_struct *alloc_uid(kuid_t uid)