Revert "sched: improve preempt debugging"
authorIngo Molnar <mingo@elte.hu>
Mon, 12 Jan 2009 12:00:50 +0000 (13:00 +0100)
committerIngo Molnar <mingo@elte.hu>
Mon, 12 Jan 2009 12:00:50 +0000 (13:00 +0100)
This reverts commit 7317d7b87edb41a9135e30be1ec3f7ef817c53dd.

This has been reported (and bisected) by Alexey Zaytsev and
Kamalesh Babulal to produce annoying warnings during bootup
on both x86 and powerpc.

kernel_locked() is not a valid test in IRQ context (we update the
BKL's ->lock_depth and the preempt count separately and non-atomicalyy),
so we cannot put it into the generic preempt debugging checks which
can run in IRQ contexts too.

Reported-and-bisected-by: Alexey Zaytsev <alexey.zaytsev@gmail.com>
Reported-and-bisected-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
kernel/sched.c

index 8be2c13b50d018cc69280829e14e31612d4deddd..3b630d8826605eb4e579a2b2ae48208b52f2de22 100644 (file)
@@ -4440,7 +4440,7 @@ void __kprobes sub_preempt_count(int val)
        /*
         * Underflow?
         */
-       if (DEBUG_LOCKS_WARN_ON(val > preempt_count() - (!!kernel_locked())))
+       if (DEBUG_LOCKS_WARN_ON(val > preempt_count()))
                return;
        /*
         * Is the spinlock portion underflowing?