On 23.12.2016 11:48, Peter Zijlstra wrote:
> On Wed, Dec 21, 2016 at 07:46:33PM +0100, Nicolai Hähnle wrote:
>> diff --git a/include/linux/ww_mutex.h b/include/linux/ww_mutex.h
>> index a5960e5..b2eaaab 100644
>> --- a/include/linux/ww_mutex.h
>> +++ b/include/linux/ww_mutex.h
>> @@ -186,11 +186,6 @@ static inline void ww_acquire_fini(struct
>> ww_acquire_ctx *ctx)
>> #endif
>> }
>>
>> -extern int __must_check __ww_mutex_lock(struct ww_mutex *lock,
>> - struct ww_acquire_ctx *ctx);
>> -extern int __must_check __ww_mutex_lock_interruptible(struct ww_mutex *lock,
>> - struct ww_acquire_ctx
>> *ctx);
>> -
>> /**
>> * ww_mutex_lock - acquire the w/w mutex
>> * @lock: the mutex to be acquired
>> @@ -220,10 +215,8 @@ extern int __must_check
>> __ww_mutex_lock_interruptible(struct ww_mutex *lock,
>> *
>> * A mutex acquired with this function must be released with
>> ww_mutex_unlock.
>> */
>> -static inline int ww_mutex_lock(struct ww_mutex *lock, struct
>> ww_acquire_ctx *ctx)
>> -{
>> - return __ww_mutex_lock(lock, ctx);
>> -}
>> +extern int __must_check ww_mutex_lock(struct ww_mutex *lock,
>> + struct ww_acquire_ctx *ctx);
>>
>> /**
>> * ww_mutex_lock_interruptible - acquire the w/w mutex, interruptible
>> @@ -255,11 +248,8 @@ static inline int ww_mutex_lock(struct ww_mutex *lock,
>> struct ww_acquire_ctx *ct
>> *
>> * A mutex acquired with this function must be released with
>> ww_mutex_unlock.
>> */
>> -static inline int __must_check ww_mutex_lock_interruptible(struct ww_mutex
>> *lock,
>> - struct
>> ww_acquire_ctx *ctx)
>> -{
>> - return __ww_mutex_lock_interruptible(lock, ctx);
>> -}
>> +extern int __must_check ww_mutex_lock_interruptible(struct ww_mutex *lock,
>> + struct ww_acquire_ctx *ctx);
>>
>> /**
>> * ww_mutex_lock_slow - slowpath acquiring of the w/w mutex
>> diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c
>> index a41bec2..282c6de 100644
>
> For some reason this patch appears to make lib/locking-selftest.c really
> unhappy.
>
> I get endless streams of:
>
> ../lib/locking-selftest.c: In function âww_test_fail_acquireâ:
> ../lib/locking-selftest.c:1141:6: error: void value not ignored as it ought
> to be
> ret = WWL(&o, &t);
> ^
>
> Apparently GCC gets confused about __much_check on inline functions or
> something, or I got the patch wrong.
Weird, I'm not getting that, and it makes no sense either from a quick
glimpse of the code. Is there anything beside
CONFIG_DEBUG_LOCKING_API_SELFTESTS I would have to enable to trigger
this? FWIW:
$ gcc --version
gcc (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609
>
>
