[PATCH v3 08/10] perf/hisi_uncore: Avoid placing cpumask on the stack
Dawei Li
dawei.li at shingroup.cn
Wed Apr 3 08:59:48 PDT 2024
In general it's preferable to avoid placing cpumasks on the stack, as
for large values of NR_CPUS these can consume significant amounts of
stack space and make stack overflows more likely.
Use cpumask_any_and_but() to avoid the need for a temporary cpumask on
the stack.
Suggested-by: Mark Rutland <mark.rutland at arm.com>
Reviewed-by: Mark Rutland <mark.rutland at arm.com>
Signed-off-by: Dawei Li <dawei.li at shingroup.cn>
---
drivers/perf/hisilicon/hisi_uncore_pmu.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/drivers/perf/hisilicon/hisi_uncore_pmu.c b/drivers/perf/hisilicon/hisi_uncore_pmu.c
index 04031450d5fe..ccc9191ad1b6 100644
--- a/drivers/perf/hisilicon/hisi_uncore_pmu.c
+++ b/drivers/perf/hisilicon/hisi_uncore_pmu.c
@@ -504,7 +504,6 @@ int hisi_uncore_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
{
struct hisi_pmu *hisi_pmu = hlist_entry_safe(node, struct hisi_pmu,
node);
- cpumask_t pmu_online_cpus;
unsigned int target;
if (!cpumask_test_and_clear_cpu(cpu, &hisi_pmu->associated_cpus))
@@ -518,9 +517,8 @@ int hisi_uncore_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
hisi_pmu->on_cpu = -1;
/* Choose a new CPU to migrate ownership of the PMU to */
- cpumask_and(&pmu_online_cpus, &hisi_pmu->associated_cpus,
- cpu_online_mask);
- target = cpumask_any_but(&pmu_online_cpus, cpu);
+ target = cpumask_any_and_but(&hisi_pmu->associated_cpus,
+ cpu_online_mask, cpu);
if (target >= nr_cpu_ids)
return 0;
--
2.27.0
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