From: Dawei Li Date: Wed, 3 Apr 2024 15:59:50 +0000 (+0800) Subject: perf/thunderx2: Avoid placing cpumask on the stack X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=595275ca498485667039e8c190453a9a684687cb;p=linux.git perf/thunderx2: 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 Reviewed-by: Mark Rutland Signed-off-by: Dawei Li Link: https://lore.kernel.org/r/20240403155950.2068109-11-dawei.li@shingroup.cn Signed-off-by: Will Deacon --- diff --git a/drivers/perf/thunderx2_pmu.c b/drivers/perf/thunderx2_pmu.c index f03aa85072ec3..33e8ff3e5265a 100644 --- a/drivers/perf/thunderx2_pmu.c +++ b/drivers/perf/thunderx2_pmu.c @@ -927,9 +927,8 @@ static int tx2_uncore_pmu_online_cpu(unsigned int cpu, static int tx2_uncore_pmu_offline_cpu(unsigned int cpu, struct hlist_node *hpnode) { - int new_cpu; struct tx2_uncore_pmu *tx2_pmu; - struct cpumask cpu_online_mask_temp; + unsigned int new_cpu; tx2_pmu = hlist_entry_safe(hpnode, struct tx2_uncore_pmu, hpnode); @@ -940,11 +939,8 @@ static int tx2_uncore_pmu_offline_cpu(unsigned int cpu, if (tx2_pmu->hrtimer_callback) hrtimer_cancel(&tx2_pmu->hrtimer); - cpumask_copy(&cpu_online_mask_temp, cpu_online_mask); - cpumask_clear_cpu(cpu, &cpu_online_mask_temp); - new_cpu = cpumask_any_and( - cpumask_of_node(tx2_pmu->node), - &cpu_online_mask_temp); + new_cpu = cpumask_any_and_but(cpumask_of_node(tx2_pmu->node), + cpu_online_mask, cpu); tx2_pmu->cpu = new_cpu; if (new_cpu >= nr_cpu_ids)