From caafa4324335aeb11bc233d5f87aca8cce30beba Mon Sep 17 00:00:00 2001 From: Pavel Emelyanov Date: Wed, 30 Apr 2008 00:54:31 -0700 Subject: [PATCH] pidns: make pid->level and pid_ns->level unsigned These values represent the nesting level of a namespace and pids living in it, and it's always non-negative. Turning this from int to unsigned int saves some space in pid.c (11 bytes on x86 and 64 on ia64) by letting the compiler optimize the pid_nr_ns a bit. E.g. on ia64 this removes the sign extension calls, which compiler adds to optimize access to pid->nubers[ns->level]. Signed-off-by: Pavel Emelyanov Cc: "Eric W. Biederman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/pid.h | 2 +- include/linux/pid_namespace.h | 2 +- kernel/pid_namespace.c | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) diff --git a/include/linux/pid.h b/include/linux/pid.h index 8d199033c0c..c21c7e8124a 100644 --- a/include/linux/pid.h +++ b/include/linux/pid.h @@ -60,7 +60,7 @@ struct pid /* lists of tasks that use this pid */ struct hlist_head tasks[PIDTYPE_MAX]; struct rcu_head rcu; - int level; + unsigned int level; struct upid numbers[1]; }; diff --git a/include/linux/pid_namespace.h b/include/linux/pid_namespace.h index fcd61fa2c83..caff5283d15 100644 --- a/include/linux/pid_namespace.h +++ b/include/linux/pid_namespace.h @@ -20,7 +20,7 @@ struct pid_namespace { int last_pid; struct task_struct *child_reaper; struct kmem_cache *pid_cachep; - int level; + unsigned int level; struct pid_namespace *parent; #ifdef CONFIG_PROC_FS struct vfsmount *proc_mnt; diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c index 5ca37fa50be..98702b4b885 100644 --- a/kernel/pid_namespace.c +++ b/kernel/pid_namespace.c @@ -66,7 +66,7 @@ err_alloc: return NULL; } -static struct pid_namespace *create_pid_namespace(int level) +static struct pid_namespace *create_pid_namespace(unsigned int level) { struct pid_namespace *ns; int i;