Notes: find_next_offset searches for an available "cleaned bit"
in the respective pid bitmap (page), so returns the offset if found,
otherwise it returns a value equals to BITS_PER_PAGE (invalid offset).
For example, suppose find_next_offset didn't find any available
bit, so there's no purpose to call mk_pid (Wasteful Cpu Cycles)
since it only computes a new PID based on a *valid* offset of
the current map.
Therefore, I found it could be better to call mk_pid after
the checking (offset < BITS_PER_PAGE) returned sucessfully!
Signed-off-by: Raphael S.Carvalho <[email protected]>
---
kernel/pid.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/kernel/pid.c b/kernel/pid.c
index 047dc62..7ecb09a 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -190,8 +190,8 @@ static int alloc_pidmap(struct pid_namespace *pid_ns)
return pid;
}
offset = find_next_offset(map, offset);
- pid = mk_pid(pid_ns, map, offset);
- } while (offset < BITS_PER_PAGE && pid < pid_max);
+ } while (offset < BITS_PER_PAGE &&
+ (pid = mk_pid(pid_ns, map, offset)) < pid_max);
}
if (map < &pid_ns->pidmap[(pid_max-1)/BITS_PER_PAGE]) {
++map;
--
1.7.2.5