[PATCH 1/2] KVM: lib: use jump label to handle resource release in irq_bypass_register_consumer()

From: linmiaohe
Date: Thu Dec 05 2019 - 21:54:20 EST


From: Miaohe Lin <linmiaohe@xxxxxxxxxx>

Use out_err jump label to handle resource release. It's a
good practice to release resource in one place and help
eliminate some duplicated code.

Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
---
virt/lib/irqbypass.c | 19 ++++++++++---------
1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/virt/lib/irqbypass.c b/virt/lib/irqbypass.c
index 43de8ae78fa1..cb0c801b3bc2 100644
--- a/virt/lib/irqbypass.c
+++ b/virt/lib/irqbypass.c
@@ -179,6 +179,7 @@ int irq_bypass_register_consumer(struct irq_bypass_consumer *consumer)
{
struct irq_bypass_consumer *tmp;
struct irq_bypass_producer *producer;
+ int ret;

if (!consumer->token ||
!consumer->add_producer || !consumer->del_producer)
@@ -193,20 +194,16 @@ int irq_bypass_register_consumer(struct irq_bypass_consumer *consumer)

list_for_each_entry(tmp, &consumers, node) {
if (tmp->token == consumer->token || tmp == consumer) {
- mutex_unlock(&lock);
- module_put(THIS_MODULE);
- return -EBUSY;
+ ret = -EBUSY;
+ goto out_err;
}
}

list_for_each_entry(producer, &producers, node) {
if (producer->token == consumer->token) {
- int ret = __connect(producer, consumer);
- if (ret) {
- mutex_unlock(&lock);
- module_put(THIS_MODULE);
- return ret;
- }
+ ret = __connect(producer, consumer);
+ if (ret)
+ goto out_err;
break;
}
}
@@ -216,6 +213,10 @@ int irq_bypass_register_consumer(struct irq_bypass_consumer *consumer)
mutex_unlock(&lock);

return 0;
+out_err:
+ mutex_unlock(&lock);
+ module_put(THIS_MODULE);
+ return ret;
}
EXPORT_SYMBOL_GPL(irq_bypass_register_consumer);

--
2.19.1