sched: Get rid of lock_depth

Neil Brown pointed out that lock_depth somehow escaped the BKL
removal work.  Let's get rid of it now.

Note that the perf scripting utilities still have a bunch of
code for dealing with common_lock_depth in tracepoints; I have
left that in place in case anybody wants to use that code with
older kernels.

Suggested-by: Neil Brown <neilb@suse.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20110422111910.456c0e84@bike.lwn.net
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 1 insertions, 10 deletions

diff --git a/kernel/sched.c b/kernel/sched.c
index 8cb0a5769a16..9cde2dd229c9 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -4121,12 +4121,6 @@ static inline void schedule_debug(struct task_struct *prev)
         profile_hit(SCHED_PROFILING, __builtin_return_address(0));
 
         schedstat_inc(this_rq(), sched_count);
-#ifdef CONFIG_SCHEDSTATS
-        if (unlikely(prev->lock_depth >= 0)) {
-                schedstat_inc(this_rq(), rq_sched_info.bkl_count);
-                schedstat_inc(prev, sched_info.bkl_count);
-        }
-#endif
 }
 
 static void put_prev_task(struct rq *rq, struct task_struct *prev)
@@ -5852,11 +5846,8 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu)
         raw_spin_unlock_irqrestore(&rq->lock, flags);
 
         /* Set the preempt count _outside_ the spinlocks! */
-#if defined(CONFIG_PREEMPT)
-        task_thread_info(idle)->preempt_count = (idle->lock_depth >= 0);
-#else
         task_thread_info(idle)->preempt_count = 0;
-#endif
+
         /*
          * The idle tasks have their own, simple scheduling class:
          */