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sched/debug: Fix printing large integers on 32-bit platforms
authorPeter Zijlstra <a.p.zijlstra@chello.nl>
Mon, 14 May 2012 12:34:00 +0000 (14:34 +0200)
committerIngo Molnar <mingo@kernel.org>
Mon, 14 May 2012 13:05:28 +0000 (15:05 +0200)
commit13e099d2f77e1da3e4046860c48d956588633613
treef538267ca46bd3647000140f6888045c5114bc0f
parente44bc5c5d00ee9b56dd87db47ed827d52948b9fa
sched/debug: Fix printing large integers on 32-bit platforms

Some numbers like nr_running and nr_uninterruptible are fundamentally
unsigned since its impossible to have a negative amount of tasks, yet
we still print them as signed to easily recognise the underflow
condition.

rq->nr_uninterruptible has 'special' accounting and can in fact very
easily become negative on a per-cpu basis.

It was noted that since the P() macro assumes things are long long and
the promotion of unsigned 'int/long' to long long on 32bit doesn't
sign extend we print silly large numbers instead of the easier to read
signed numbers.

Therefore extend the P() macro to not require the sign extention.

Reported-by: Diwakar Tundlam <dtundlam@nvidia.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-gk5tm8t2n4ix2vkpns42uqqp@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
kernel/sched/debug.c