perf/qcom_l2: Avoid placing cpumask on the stack

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@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Dawei Li <dawei.li@shingroup.cn>
Link: https://lore.kernel.org/r/20240403155950.2068109-10-dawei.li@shingroup.cn
Signed-off-by: Will Deacon <will@kernel.org>

diff --git a/drivers/perf/qcom_l2_pmu.c b/drivers/perf/qcom_l2_pmu.c
index 148df5ae8ef8322e8ca577868b64cbb3099c0cc2..b5a44dc1dc3a56f8895043779dcd405f9432836b 100644 (file)
--- a/drivers/perf/qcom_l2_pmu.c
+++ b/drivers/perf/qcom_l2_pmu.c
@@ -801,9 +801,8 @@ static int l2cache_pmu_online_cpu(unsigned int cpu, struct hlist_node *node)
 
 static int l2cache_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
 {
-       struct cluster_pmu *cluster;
        struct l2cache_pmu *l2cache_pmu;
-       cpumask_t cluster_online_cpus;
+       struct cluster_pmu *cluster;
        unsigned int target;
 
        l2cache_pmu = hlist_entry_safe(node, struct l2cache_pmu, node);
@@ -820,9 +819,8 @@ static int l2cache_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
        cluster->on_cpu = -1;
 
        /* Any other CPU for this cluster which is still online */
-       cpumask_and(&cluster_online_cpus, &cluster->cluster_cpus,
-                   cpu_online_mask);
-       target = cpumask_any_but(&cluster_online_cpus, cpu);
+       target = cpumask_any_and_but(&cluster->cluster_cpus,
+                                    cpu_online_mask, cpu);
        if (target >= nr_cpu_ids) {
                disable_irq(cluster->irq);
                return 0;