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Message-ID: <b53b3a3d-6417-44b7-8cc4-42643608deac@salutedevices.com>
Date: Sat, 16 Dec 2023 14:47:31 +0300
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Subject: Re: [PATCH 1/2] locking/mutex: Clean up mutex.h
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To: Waiman Long <longman@redhat.com>, Peter Zijlstra <peterz@infradead.org>,
	Ingo Molnar <mingo@redhat.com>, Will Deacon <will@kernel.org>, Boqun Feng
	<boqun.feng@gmail.com>, Andrew Morton <akpm@linux-foundation.org>
CC: <linux-kernel@vger.kernel.org>
References: <20231216013656.1382213-1-longman@redhat.com>
From: George Stark <gnstark@salutedevices.com>
In-Reply-To: <20231216013656.1382213-1-longman@redhat.com>
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Hello Waiman

Thanks for this patch! It'll be much easier to extend mutex.h with this 
change.

Just curious is there a reason we can't move mutex_init macro outside 
big #ifdef to eliminate duplicated declaration too?

Either way,
Reviewed-by: George Stark <gnstark@salutedevices.com>

On 12/16/23 04:36, Waiman Long wrote:
> CONFIG_DEBUG_MUTEXES and CONFIG_PREEMPT_RT are mutually exclusive. They
> can't be both set at the same time.  Move down the mutex_destroy()
> function declaration to the bottom of mutex.h to eliminate duplicated
> mutex_destroy() declaration.
> 
> Also remove the duplicated mutex_trylock() function declaration in the
> CONFIG_PREEMPT_RT section.
> 
> Signed-off-by: Waiman Long <longman@redhat.com>
> ---
>   include/linux/mutex.h | 23 +++++++++++------------
>   1 file changed, 11 insertions(+), 12 deletions(-)
> 
> diff --git a/include/linux/mutex.h b/include/linux/mutex.h
> index a33aa9eb9fc3..f3ae911580bf 100644
> --- a/include/linux/mutex.h
> +++ b/include/linux/mutex.h
> @@ -77,18 +77,10 @@ struct mutex {
>   };
>   
>   #ifdef CONFIG_DEBUG_MUTEXES
> -
> -#define __DEBUG_MUTEX_INITIALIZER(lockname)				\
> +# define __DEBUG_MUTEX_INITIALIZER(lockname)				\
>   	, .magic = &lockname
> -
> -extern void mutex_destroy(struct mutex *lock);
> -
>   #else
> -
>   # define __DEBUG_MUTEX_INITIALIZER(lockname)
> -
> -static inline void mutex_destroy(struct mutex *lock) {}
> -
>   #endif
>   
>   /**
> @@ -151,9 +143,6 @@ struct mutex {
>   
>   extern void __mutex_rt_init(struct mutex *lock, const char *name,
>   			    struct lock_class_key *key);
> -extern int mutex_trylock(struct mutex *lock);
> -
> -static inline void mutex_destroy(struct mutex *lock) { }
>   
>   #define mutex_is_locked(l)	rt_mutex_base_is_locked(&(l)->rtmutex)
>   
> @@ -220,6 +209,16 @@ extern void mutex_unlock(struct mutex *lock);
>   
>   extern int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock);
>   
> +#ifdef CONFIG_DEBUG_MUTEXES
> +
> +extern void mutex_destroy(struct mutex *lock);
> +
> +#else
> +
> +static inline void mutex_destroy(struct mutex *lock) {}
> +
> +#endif
> +
>   DEFINE_GUARD(mutex, struct mutex *, mutex_lock(_T), mutex_unlock(_T))
>   DEFINE_FREE(mutex, struct mutex *, if (_T) mutex_unlock(_T))
>   

-- 
Best regards
George