Message ID | 1482346000-9927-6-git-send-email-nhaehnle@gmail.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
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 ‘ww_test_fail_acquire’: ../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.
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 ‘ww_test_fail_acquire’: > ../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 > >
On Fri, Dec 23, 2016 at 12:16:03PM +0100, Nicolai Hähnle wrote: > >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 ‘ww_test_fail_acquire’: > >../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? Not entirely sure, I'm building an allmodconfig. > FWIW: > > $ gcc --version > gcc (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609 gcc (Debian 6.2.1-5) 6.2.1 20161124
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 --- a/kernel/locking/mutex.c +++ b/kernel/locking/mutex.c @@ -818,7 +818,7 @@ ww_mutex_deadlock_injection(struct ww_mutex *lock, struct ww_acquire_ctx *ctx) } int __sched -__ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ctx) +ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ctx) { int ret; @@ -831,10 +831,10 @@ __ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ctx) return ret; } -EXPORT_SYMBOL_GPL(__ww_mutex_lock); +EXPORT_SYMBOL_GPL(ww_mutex_lock); int __sched -__ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ctx) +ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ctx) { int ret; @@ -848,7 +848,7 @@ __ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ctx) return ret; } -EXPORT_SYMBOL_GPL(__ww_mutex_lock_interruptible); +EXPORT_SYMBOL_GPL(ww_mutex_lock_interruptible); #endif @@ -1025,7 +1025,7 @@ EXPORT_SYMBOL(mutex_trylock); #ifndef CONFIG_DEBUG_LOCK_ALLOC int __sched -__ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ctx) +ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ctx) { might_sleep(); @@ -1037,10 +1037,10 @@ __ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ctx) return __ww_mutex_lock_slowpath(lock, ctx); } -EXPORT_SYMBOL(__ww_mutex_lock); +EXPORT_SYMBOL(ww_mutex_lock); int __sched -__ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ctx) +ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ctx) { might_sleep(); @@ -1052,7 +1052,7 @@ __ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ctx) return __ww_mutex_lock_interruptible_slowpath(lock, ctx); } -EXPORT_SYMBOL(__ww_mutex_lock_interruptible); +EXPORT_SYMBOL(ww_mutex_lock_interruptible); #endif