From: Peter Zijlstra Date: Mon, 14 May 2012 12:34:00 +0000 (+0200) Subject: sched/debug: Fix printing large integers on 32-bit platforms X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=13e099d2f77e1da3e4046860c48d956588633613;p=deliverable%2Flinux.git 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 Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/n/tip-gk5tm8t2n4ix2vkpns42uqqp@git.kernel.org Signed-off-by: Ingo Molnar --- diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c index 31e4f61a1629..6f79596e0ea9 100644 --- a/kernel/sched/debug.c +++ b/kernel/sched/debug.c @@ -260,8 +260,14 @@ static void print_cpu(struct seq_file *m, int cpu) SEQ_printf(m, "\ncpu#%d\n", cpu); #endif -#define P(x) \ - SEQ_printf(m, " .%-30s: %Ld\n", #x, (long long)(rq->x)) +#define P(x) \ +do { \ + if (sizeof(rq->x) == 4) \ + SEQ_printf(m, " .%-30s: %ld\n", #x, (long)(rq->x)); \ + else \ + SEQ_printf(m, " .%-30s: %Ld\n", #x, (long long)(rq->x));\ +} while (0) + #define PN(x) \ SEQ_printf(m, " .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rq->x))