diff mbox series

[1/1] RDMA/rtrs: Require holding rcu_read_lock explicitly

Message ID 20230918153646.338878-1-yanjun.zhu@intel.com (mailing list archive)
State Superseded
Headers show
Series [1/1] RDMA/rtrs: Require holding rcu_read_lock explicitly | expand

Commit Message

Zhu Yanjun Sept. 18, 2023, 3:36 p.m. UTC
From: Zhu Yanjun <yanjun.zhu@linux.dev>

No functional change. The function get_next_path_rr needs to hold
rcu_read_lock. As such, if no rcu read lock, warnings will pop out.

Signed-off-by: Zhu Yanjun <yanjun.zhu@linux.dev>
---
 drivers/infiniband/ulp/rtrs/rtrs-clt.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

Comments

Jinpu Wang Sept. 18, 2023, 4:12 p.m. UTC | #1
On Mon, Sep 18, 2023 at 5:37 PM Zhu Yanjun <yanjun.zhu@intel.com> wrote:
>
> From: Zhu Yanjun <yanjun.zhu@linux.dev>
>
> No functional change. The function get_next_path_rr needs to hold
> rcu_read_lock. As such, if no rcu read lock, warnings will pop out.
>
> Signed-off-by: Zhu Yanjun <yanjun.zhu@linux.dev>
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Thx!
> ---
>  drivers/infiniband/ulp/rtrs/rtrs-clt.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt.c b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
> index b6ee801fd0ff..bc4b70318bf4 100644
> --- a/drivers/infiniband/ulp/rtrs/rtrs-clt.c
> +++ b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
> @@ -775,7 +775,7 @@ rtrs_clt_get_next_path_or_null(struct list_head *head, struct rtrs_clt_path *clt
>   * Related to @MP_POLICY_RR
>   *
>   * Locks:
> - *    rcu_read_lock() must be hold.
> + *    rcu_read_lock() must be held.
>   */
>  static struct rtrs_clt_path *get_next_path_rr(struct path_it *it)
>  {
> @@ -783,6 +783,11 @@ static struct rtrs_clt_path *get_next_path_rr(struct path_it *it)
>         struct rtrs_clt_path *path;
>         struct rtrs_clt_sess *clt;
>
> +       /*
> +        * Assert that rcu lock must be held
> +        */
> +       WARN_ON_ONCE(!rcu_read_lock_held());
> +
>         clt = it->clt;
>
>         /*
> --
> 2.40.1
>
Leon Romanovsky Sept. 19, 2023, 7:09 a.m. UTC | #2
On Mon, Sep 18, 2023 at 11:36:46PM +0800, Zhu Yanjun wrote:
> From: Zhu Yanjun <yanjun.zhu@linux.dev>
> 
> No functional change. The function get_next_path_rr needs to hold
> rcu_read_lock. As such, if no rcu read lock, warnings will pop out.
> 
> Signed-off-by: Zhu Yanjun <yanjun.zhu@linux.dev>
> ---
>  drivers/infiniband/ulp/rtrs/rtrs-clt.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt.c b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
> index b6ee801fd0ff..bc4b70318bf4 100644
> --- a/drivers/infiniband/ulp/rtrs/rtrs-clt.c
> +++ b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
> @@ -775,7 +775,7 @@ rtrs_clt_get_next_path_or_null(struct list_head *head, struct rtrs_clt_path *clt
>   * Related to @MP_POLICY_RR
>   *
>   * Locks:
> - *    rcu_read_lock() must be hold.
> + *    rcu_read_lock() must be held.
>   */
>  static struct rtrs_clt_path *get_next_path_rr(struct path_it *it)
>  {
> @@ -783,6 +783,11 @@ static struct rtrs_clt_path *get_next_path_rr(struct path_it *it)
>  	struct rtrs_clt_path *path;
>  	struct rtrs_clt_sess *clt;
>  
> +	/*
> +	 * Assert that rcu lock must be held
> +	 */
> +	WARN_ON_ONCE(!rcu_read_lock_held());

Let's use RCU_LOCKDEP_WARN(..) macro.

Thanks

> +
>  	clt = it->clt;
>  
>  	/*
> -- 
> 2.40.1
>
Zhu Yanjun Sept. 19, 2023, 7:21 a.m. UTC | #3
在 2023/9/19 15:09, Leon Romanovsky 写道:
> On Mon, Sep 18, 2023 at 11:36:46PM +0800, Zhu Yanjun wrote:
>> From: Zhu Yanjun <yanjun.zhu@linux.dev>
>>
>> No functional change. The function get_next_path_rr needs to hold
>> rcu_read_lock. As such, if no rcu read lock, warnings will pop out.
>>
>> Signed-off-by: Zhu Yanjun <yanjun.zhu@linux.dev>
>> ---
>>   drivers/infiniband/ulp/rtrs/rtrs-clt.c | 7 ++++++-
>>   1 file changed, 6 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt.c b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
>> index b6ee801fd0ff..bc4b70318bf4 100644
>> --- a/drivers/infiniband/ulp/rtrs/rtrs-clt.c
>> +++ b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
>> @@ -775,7 +775,7 @@ rtrs_clt_get_next_path_or_null(struct list_head *head, struct rtrs_clt_path *clt
>>    * Related to @MP_POLICY_RR
>>    *
>>    * Locks:
>> - *    rcu_read_lock() must be hold.
>> + *    rcu_read_lock() must be held.
>>    */
>>   static struct rtrs_clt_path *get_next_path_rr(struct path_it *it)
>>   {
>> @@ -783,6 +783,11 @@ static struct rtrs_clt_path *get_next_path_rr(struct path_it *it)
>>   	struct rtrs_clt_path *path;
>>   	struct rtrs_clt_sess *clt;
>>   
>> +	/*
>> +	 * Assert that rcu lock must be held
>> +	 */
>> +	WARN_ON_ONCE(!rcu_read_lock_held());
> Let's use RCU_LOCKDEP_WARN(..) macro.

Got it. Will send v2 very soon.

Zhu Yanjun

>
> Thanks
>
>> +
>>   	clt = it->clt;
>>   
>>   	/*
>> -- 
>> 2.40.1
>>
diff mbox series

Patch

diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt.c b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
index b6ee801fd0ff..bc4b70318bf4 100644
--- a/drivers/infiniband/ulp/rtrs/rtrs-clt.c
+++ b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
@@ -775,7 +775,7 @@  rtrs_clt_get_next_path_or_null(struct list_head *head, struct rtrs_clt_path *clt
  * Related to @MP_POLICY_RR
  *
  * Locks:
- *    rcu_read_lock() must be hold.
+ *    rcu_read_lock() must be held.
  */
 static struct rtrs_clt_path *get_next_path_rr(struct path_it *it)
 {
@@ -783,6 +783,11 @@  static struct rtrs_clt_path *get_next_path_rr(struct path_it *it)
 	struct rtrs_clt_path *path;
 	struct rtrs_clt_sess *clt;
 
+	/*
+	 * Assert that rcu lock must be held
+	 */
+	WARN_ON_ONCE(!rcu_read_lock_held());
+
 	clt = it->clt;
 
 	/*