[PATCH v2 6/7] irqchip/sifive-plic: Avoid explicit cpumask allocation on stack

From: Dawei Li
Date: Tue Apr 16 2024 - 04:57:04 EST


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

Signed-off-by: Dawei Li <dawei.li@xxxxxxxxxxxx>
---
drivers/irqchip/irq-sifive-plic.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c
index f3d4cb9e34f7..8fb183ced1e7 100644
--- a/drivers/irqchip/irq-sifive-plic.c
+++ b/drivers/irqchip/irq-sifive-plic.c
@@ -164,15 +164,12 @@ static int plic_set_affinity(struct irq_data *d,
const struct cpumask *mask_val, bool force)
{
unsigned int cpu;
- struct cpumask amask;
struct plic_priv *priv = irq_data_get_irq_chip_data(d);

- cpumask_and(&amask, &priv->lmask, mask_val);
-
if (force)
- cpu = cpumask_first(&amask);
+ cpu = cpumask_first_and(&priv->lmask, mask_val);
else
- cpu = cpumask_any_and(&amask, cpu_online_mask);
+ cpu = cpumask_first_and_and(&priv->lmask, mask_val, cpu_online_mask);

if (cpu >= nr_cpu_ids)
return -EINVAL;
--
2.27.0