[PATCH] bus: arm-ccn: Handle correctly no-more-cpus case
Pawel Moll
pawel.moll at arm.com
Thu May 14 03:50:24 PDT 2015
When migrating events the driver picks another cpu using
cpumask_any_but() function, which returns value >= nr_cpu_ids
when there is none available, not a negative value as the code
assumed. Fixed now.
Reported-by: Dan Carpenter <dan.carpenter at oracle.com>
Signed-off-by: Pawel Moll <pawel.moll at arm.com>
---
Another day, another arm-ccn.c update...
This time Dan's static checker spotted unsigned int target
being expected to carry negative values. Fixed now.
Interestingly enough, cpumask_any_but() implementation (and its
normal prototype) returns int, but version for NR_CPUS == 1 case,
inlined in linux/cpumask.h returns unsigned int...
drivers/bus/arm-ccn.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/bus/arm-ccn.c b/drivers/bus/arm-ccn.c
index 7d9879e..cc322fb 100644
--- a/drivers/bus/arm-ccn.c
+++ b/drivers/bus/arm-ccn.c
@@ -1184,7 +1184,7 @@ static int arm_ccn_pmu_cpu_notifier(struct notifier_block *nb,
if (!cpumask_test_and_clear_cpu(cpu, &dt->cpu))
break;
target = cpumask_any_but(cpu_online_mask, cpu);
- if (target < 0)
+ if (target >= nr_cpu_ids)
break;
perf_pmu_migrate_context(&dt->pmu, cpu, target);
cpumask_set_cpu(target, &dt->cpu);
--
2.1.0
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