rcutorture: remove useless INIT_LIST_HEAD()

[PATCH] rcutorture: remove useless INIT_LIST_HEAD()

Posted by Haowen Bai 3 years, 12 months ago

list rcu_torture_freelist has been inited staticly through LIST_HEAD,
so there's no need to call another INIT_LIST_HEAD. Simply remove
it.

Signed-off-by: Haowen Bai <baihaowen@meizu.com>
---
 kernel/rcu/rcutorture.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index faf6b4c7a757..0005e259c4ce 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -3247,7 +3247,6 @@ rcu_torture_init(void)
 
 	/* Set up the freelist. */
 
-	INIT_LIST_HEAD(&rcu_torture_freelist);
 	for (i = 0; i < ARRAY_SIZE(rcu_tortures); i++) {
 		rcu_tortures[i].rtort_mbtest = 0;
 		list_add_tail(&rcu_tortures[i].rtort_free,
-- 
2.7.4

Re: [PATCH] rcutorture: remove useless INIT_LIST_HEAD()

Posted by Paul E. McKenney 3 years, 12 months ago

On Wed, May 11, 2022 at 10:47:04AM +0800, Haowen Bai wrote:
> list rcu_torture_freelist has been inited staticly through LIST_HEAD,
> so there's no need to call another INIT_LIST_HEAD. Simply remove
> it.
> 
> Signed-off-by: Haowen Bai <baihaowen@meizu.com>

For kernels with built-in rcutorture that starts automatically at
boot, you are quite correct.

But wouldn't there be trouble in the case where someone does a series of
"modprobe rcutorture" "rmmod rcutorture" commands?

							Thanx, Paul

> ---
>  kernel/rcu/rcutorture.c | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
> index faf6b4c7a757..0005e259c4ce 100644
> --- a/kernel/rcu/rcutorture.c
> +++ b/kernel/rcu/rcutorture.c
> @@ -3247,7 +3247,6 @@ rcu_torture_init(void)
>  
>  	/* Set up the freelist. */
>  
> -	INIT_LIST_HEAD(&rcu_torture_freelist);
>  	for (i = 0; i < ARRAY_SIZE(rcu_tortures); i++) {
>  		rcu_tortures[i].rtort_mbtest = 0;
>  		list_add_tail(&rcu_tortures[i].rtort_free,
> -- 
> 2.7.4
>

Re: [PATCH] rcutorture: remove useless INIT_LIST_HEAD()

Posted by baihaowen 3 years, 12 months ago

在 2022/5/11 上午11:01, Paul E. McKenney 写道:
> On Wed, May 11, 2022 at 10:47:04AM +0800, Haowen Bai wrote:
>> list rcu_torture_freelist has been inited staticly through LIST_HEAD,
>> so there's no need to call another INIT_LIST_HEAD. Simply remove
>> it.
>>
>> Signed-off-by: Haowen Bai <baihaowen@meizu.com>
> For kernels with built-in rcutorture that starts automatically at
> boot, you are quite correct.
>
> But wouldn't there be trouble in the case where someone does a series of
> "modprobe rcutorture" "rmmod rcutorture" commands?
>
> 							Thanx, Paul
>
>> ---
>>  kernel/rcu/rcutorture.c | 1 -
>>  1 file changed, 1 deletion(-)
>>
>> diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
>> index faf6b4c7a757..0005e259c4ce 100644
>> --- a/kernel/rcu/rcutorture.c
>> +++ b/kernel/rcu/rcutorture.c
>> @@ -3247,7 +3247,6 @@ rcu_torture_init(void)
>>  
>>  	/* Set up the freelist. */
>>  
>> -	INIT_LIST_HEAD(&rcu_torture_freelist);
>>  	for (i = 0; i < ARRAY_SIZE(rcu_tortures); i++) {
>>  		rcu_tortures[i].rtort_mbtest = 0;
>>  		list_add_tail(&rcu_tortures[i].rtort_free,
>> -- 
>> 2.7.4
>>
Thank you for kindly reply, got it.

-- 
Haowen Bai