Re: [PATCH] cgroup: drop unneeded semicolon

[Waiman Long <longman@redhat.com>]

On 8/1/26 3:09 PM, Julia Lawall wrote:
> When a function-like macro expands to an expression, that expression
> doesn't need a semicolon after it.  All uses have been verified to
> have their own semicolons.
>
> This was found using the following Coccinelle semantic patch:
>
> @r@
> identifier i : script:ocaml() { String.lowercase_ascii i = i };
> expression e;
> @@
>
> *#define i(...) e;
>
> Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
>
> ---
>   kernel/cgroup/cgroup.c |    2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
> index 38f8d9df8..f87fc4550 100644
> --- a/kernel/cgroup/cgroup.c
> +++ b/kernel/cgroup/cgroup.c
> @@ -104,7 +104,7 @@ DEFINE_PERCPU_RWSEM(cgroup_threadgroup_rwsem);
>   #define cgroup_assert_mutex_or_rcu_locked()				\
>   	RCU_LOCKDEP_WARN(!rcu_read_lock_held() &&			\
>   			   !lockdep_is_held(&cgroup_mutex),		\
> -			   "cgroup_mutex or RCU read lock required");
> +			   "cgroup_mutex or RCU read lock required")
>   
>   /*
>    * cgroup destruction makes heavy use of work items and there can be a lot
>
The RCU_LOCKDEP_WARN() macro is basically a "do { ...} while (0...)" 
statement. It doesn't have a ';' at the end.  So your commit log isn't 
right.

An additional semicolon at the end doesn't harm. By removing the 
semicolon, even if not needed, may make people wonder if it is right 
when reading the code wasting their time to figure out if it is all 
right. So I don't see any advantage in removing it.

Cheers,
Longman