[PATCH] cpuset semaphore depth check optimize

Optimize the deadlock avoidance check on the global cpuset
semaphore cpuset_sem.  Instead of adding a depth counter to the
task struct of each task, rather just two words are enough, one
to store the depth and the other the current cpuset_sem holder.

Thanks to Nikita Danilov for the idea.

Signed-off-by: Paul Jackson <pj@sgi.com>

[ We may want to change this further, but at least it's now
  a totally internal decision to the cpusets code ]

Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 0 insertions, 1 deletions

diff --git a/include/linux/sched.h b/include/linux/sched.h
index ed3bb19d1337..38c8654aaa96 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -785,7 +785,6 @@ struct task_struct {
         short il_next;
 #endif
 #ifdef CONFIG_CPUSETS
-        short cpuset_sem_nest_depth;
         struct cpuset *cpuset;
         nodemask_t mems_allowed;
         int cpuset_mems_generation;