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 <xemul@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/pid.h b/include/linux/pid.h
index 8d19903..c21c7e8 100644
--- a/include/linux/pid.h
+++ b/include/linux/pid.h
@@ -60,7 +60,7 @@
/* 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];
};