Messages in this thread Patch in this message | | | From | Dawei Li <> | Subject | [PATCH v3 07/10] perf/hisi_pcie: Avoid placing cpumask on the stack | Date | Wed, 3 Apr 2024 23:59:47 +0800 |
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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> --- drivers/perf/hisilicon/hisi_pcie_pmu.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/drivers/perf/hisilicon/hisi_pcie_pmu.c b/drivers/perf/hisilicon/hisi_pcie_pmu.c index 5d1f0e9fdb08..06b192cc31d5 100644 --- 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) { -- 2.27.0
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