perf/hisi_pcie: 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>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20240403155950.2068109-8-dawei.li@shingroup.cn
Signed-off-by: Will Deacon <will@kernel.org>

diff --git a/drivers/perf/hisilicon/hisi_pcie_pmu.c b/drivers/perf/hisilicon/hisi_pcie_pmu.c
index 5d1f0e9fdb08d2ecdbff6170b8172859b196c12d..06b192cc31d5c397c1b95a5a3d4cacd9ef83fcbf 100644 (file)
--- a/drivers/perf/hisilicon/hisi_pcie_pmu.c
+++ b/drivers/perf/hisilicon/hisi_pcie_pmu.c
@@ -673,7 +673,6 @@ static int hisi_pcie_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
 {
        struct hisi_pcie_pmu *pcie_pmu = hlist_entry_safe(node, struct hisi_pcie_pmu, node);
        unsigned int target;
-       cpumask_t mask;
        int numa_node;
 
        /* Nothing to do if this CPU doesn't own the PMU */
@@ -684,10 +683,10 @@ static int hisi_pcie_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
 
        /* Choose a local CPU from all online cpus. */
        numa_node = dev_to_node(&pcie_pmu->pdev->dev);
-       if (cpumask_and(&mask, cpumask_of_node(numa_node), cpu_online_mask) &&
-           cpumask_andnot(&mask, &mask, cpumask_of(cpu)))
-               target = cpumask_any(&mask);
-       else
+
+       target = cpumask_any_and_but(cpumask_of_node(numa_node),
+                                    cpu_online_mask, cpu);
+       if (target >= nr_cpu_ids)
                target = cpumask_any_but(cpu_online_mask, cpu);
 
        if (target >= nr_cpu_ids) {