[PATCH v2 5/7] irqchip/riscv-aplic-direct: Avoid explicit cpumask allocation on stack

From: Dawei Li
Date: Tue Apr 16 2024 - 04:56:55 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-riscv-aplic-direct.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/irqchip/irq-riscv-aplic-direct.c b/drivers/irqchip/irq-riscv-aplic-direct.c
index 06bace9b7497..4a3ffe856d6c 100644
--- a/drivers/irqchip/irq-riscv-aplic-direct.c
+++ b/drivers/irqchip/irq-riscv-aplic-direct.c
@@ -54,15 +54,12 @@ static int aplic_direct_set_affinity(struct irq_data *d, const struct cpumask *m
struct aplic_direct *direct = container_of(priv, struct aplic_direct, priv);
struct aplic_idc *idc;
unsigned int cpu, val;
- struct cpumask amask;
void __iomem *target;

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

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