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cpuidle: Avoid explicit cpumask allocation on stack

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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_first_and_and() and cpumask_weight_and() to avoid the need
for a temporary cpumask on the stack.

Signed-off-by: Dawei Li <dawei.li@shingroup.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240416085454.3547175-8-dawei.li@shingroup.cn
This commit is contained in:
Dawei Li 2024-04-16 16:54:54 +08:00 committed by Thomas Gleixner
parent a7fb69ffd7
commit 6f28c4a852
1 changed files with 3 additions and 10 deletions
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13
drivers/cpuidle/coupled.c
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@ -439,13 +439,8 @@ static int cpuidle_coupled_clear_pokes(int cpu)
static bool cpuidle_coupled_any_pokes_pending(struct cpuidle_coupled *coupled)
{
cpumask_t cpus;
int ret;
cpumask_and(&cpus, cpu_online_mask, &coupled->coupled_cpus);
ret = cpumask_and(&cpus, &cpuidle_coupled_poke_pending, &cpus);
return ret;
return cpumask_first_and_and(cpu_online_mask, &coupled->coupled_cpus,
&cpuidle_coupled_poke_pending) < nr_cpu_ids;
}
/**
@ -626,9 +621,7 @@ out:
static void cpuidle_coupled_update_online_cpus(struct cpuidle_coupled *coupled)
{
cpumask_t cpus;
cpumask_and(&cpus, cpu_online_mask, &coupled->coupled_cpus);
coupled->online_count = cpumask_weight(&cpus);
coupled->online_count = cpumask_weight_and(cpu_online_mask, &coupled->coupled_cpus);
}
/**