From 0654acd8eb7de3d82d0e8dc0235f1c7a67577da4 Mon Sep 17 00:00:00 2001 From: Dawei Li Date: Mon, 15 Apr 2024 17:48:21 +0800 Subject: [PATCH] powercap: DTPM: Avoid explicit cpumask allocation on 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_weight_and() to avoid the need for a temporary cpumask on the stack. Signed-off-by: Dawei Li Signed-off-by: Rafael J. Wysocki --- drivers/powercap/dtpm_cpu.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/drivers/powercap/dtpm_cpu.c b/drivers/powercap/dtpm_cpu.c index bc90126f1b5f..6b6f51b21550 100644 --- a/drivers/powercap/dtpm_cpu.c +++ b/drivers/powercap/dtpm_cpu.c @@ -43,13 +43,11 @@ static u64 set_pd_power_limit(struct dtpm *dtpm, u64 power_limit) struct dtpm_cpu *dtpm_cpu = to_dtpm_cpu(dtpm); struct em_perf_domain *pd = em_cpu_get(dtpm_cpu->cpu); struct em_perf_state *table; - struct cpumask cpus; unsigned long freq; u64 power; int i, nr_cpus; - cpumask_and(&cpus, cpu_online_mask, to_cpumask(pd->cpus)); - nr_cpus = cpumask_weight(&cpus); + nr_cpus = cpumask_weight_and(cpu_online_mask, to_cpumask(pd->cpus)); rcu_read_lock(); table = em_perf_state_from_pd(pd); @@ -123,11 +121,9 @@ static int update_pd_power_uw(struct dtpm *dtpm) struct dtpm_cpu *dtpm_cpu = to_dtpm_cpu(dtpm); struct em_perf_domain *em = em_cpu_get(dtpm_cpu->cpu); struct em_perf_state *table; - struct cpumask cpus; int nr_cpus; - cpumask_and(&cpus, cpu_online_mask, to_cpumask(em->cpus)); - nr_cpus = cpumask_weight(&cpus); + nr_cpus = cpumask_weight_and(cpu_online_mask, to_cpumask(em->cpus)); rcu_read_lock(); table = em_perf_state_from_pd(em);