[PATCH v4 34/40] MIPS: sgi-ip27: optimize alloc_level()

From: Yury Norov
Date: Thu Jun 20 2024 - 14:08:43 EST


Simplify alloc_level by using a dedicated atomic find() API, and make
it a nice one-liner wrappers.

Signed-off-by: Yury Norov <yury.norov@xxxxxxxxx>
---
arch/mips/sgi-ip27/ip27-irq.c | 13 +++----------
1 file changed, 3 insertions(+), 10 deletions(-)

diff --git a/arch/mips/sgi-ip27/ip27-irq.c b/arch/mips/sgi-ip27/ip27-irq.c
index 00e63e9ef61d..fc29252860a3 100644
--- a/arch/mips/sgi-ip27/ip27-irq.c
+++ b/arch/mips/sgi-ip27/ip27-irq.c
@@ -13,6 +13,7 @@
#include <linux/ioport.h>
#include <linux/kernel.h>
#include <linux/bitops.h>
+#include <linux/find_atomic.h>
#include <linux/sched.h>

#include <asm/io.h>
@@ -36,17 +37,9 @@ static DEFINE_PER_CPU(unsigned long [2], irq_enable_mask);

static inline int alloc_level(void)
{
- int level;
+ int level = find_and_set_bit(hub_irq_map, IP27_HUB_IRQ_COUNT);

-again:
- level = find_first_zero_bit(hub_irq_map, IP27_HUB_IRQ_COUNT);
- if (level >= IP27_HUB_IRQ_COUNT)
- return -ENOSPC;
-
- if (test_and_set_bit(level, hub_irq_map))
- goto again;
-
- return level;
+ return level < IP27_HUB_IRQ_COUNT ? level : -ENOSPC;
}

static void enable_hub_irq(struct irq_data *d)
--
2.43.0