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Miller" , Luc Van Oostenryck , Chris Li , "Paul E. McKenney" , Alexander Potapenko , Arnd Bergmann , Bart Van Assche , Christoph Hellwig , Dmitry Vyukov , Eric Dumazet , Frederic Weisbecker , Greg Kroah-Hartman , Herbert Xu , Ian Rogers , Jann Horn , Joel Fernandes , Johannes Berg , Jonathan Corbet , Josh Triplett , Justin Stitt , Kees Cook , Kentaro Takeda , Lukas Bulwahn , Mark Rutland , Mathieu Desnoyers , Miguel Ojeda , Nathan Chancellor , Neeraj Upadhyay , Nick Desaulniers , Steven Rostedt , Tetsuo Handa , Thomas Gleixner , Thomas Graf , Uladzislau Rezki , Waiman Long , kasan-dev@googlegroups.com, linux-crypto@vger.kernel.org, linux-doc@vger.kernel.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-security-module@vger.kernel.org, linux-sparse@vger.kernel.org, linux-wireless@vger.kernel.org, llvm@lists.linux.dev, rcu@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Add support for Clang's context analysis for mutex. Signed-off-by: Marco Elver Reported-by: Bart Van Assche --- v5: * Rename "context guard" -> "context lock". v4: * Rename capability -> context analysis. v3: * Switch to DECLARE_LOCK_GUARD_1_ATTRS() (suggested by Peter) * __assert -> __assume rename --- Documentation/dev-tools/context-analysis.rst | 2 +- include/linux/mutex.h | 38 +++++++----- include/linux/mutex_types.h | 4 +- lib/test_context-analysis.c | 64 ++++++++++++++++++++ 4 files changed, 90 insertions(+), 18 deletions(-) diff --git a/Documentation/dev-tools/context-analysis.rst b/Documentation/d= ev-tools/context-analysis.rst index 746a2d275fb2..1864b6cba4d1 100644 --- a/Documentation/dev-tools/context-analysis.rst +++ b/Documentation/dev-tools/context-analysis.rst @@ -79,7 +79,7 @@ Supported Kernel Primitives ~~~~~~~~~~~~~~~~~~~~~~~~~~~ =20 Currently the following synchronization primitives are supported: -`raw_spinlock_t`, `spinlock_t`, `rwlock_t`. +`raw_spinlock_t`, `spinlock_t`, `rwlock_t`, `mutex`. =20 For context locks with an initialization function (e.g., `spin_lock_init()= `), calling this function before initializing any guarded members or globals diff --git a/include/linux/mutex.h b/include/linux/mutex.h index bf535f0118bb..89977c215cbd 100644 --- a/include/linux/mutex.h +++ b/include/linux/mutex.h @@ -62,6 +62,7 @@ do { \ static struct lock_class_key __key; \ \ __mutex_init((mutex), #mutex, &__key); \ + __assume_ctx_lock(mutex); \ } while (0) =20 /** @@ -182,13 +183,13 @@ static inline int __must_check __devm_mutex_init(stru= ct device *dev, struct mute * Also see Documentation/locking/mutex-design.rst. */ #ifdef CONFIG_DEBUG_LOCK_ALLOC -extern void mutex_lock_nested(struct mutex *lock, unsigned int subclass); +extern void mutex_lock_nested(struct mutex *lock, unsigned int subclass) _= _acquires(lock); extern void _mutex_lock_nest_lock(struct mutex *lock, struct lockdep_map *= nest_lock); extern int __must_check mutex_lock_interruptible_nested(struct mutex *lock, - unsigned int subclass); + unsigned int subclass) __cond_acquires(0, lock); extern int __must_check _mutex_lock_killable(struct mutex *lock, - unsigned int subclass, struct lockdep_map *nest_lock); -extern void mutex_lock_io_nested(struct mutex *lock, unsigned int subclass= ); + unsigned int subclass, struct lockdep_map *nest_lock) __cond_acquires(0,= lock); +extern void mutex_lock_io_nested(struct mutex *lock, unsigned int subclass= ) __acquires(lock); =20 #define mutex_lock(lock) mutex_lock_nested(lock, 0) #define mutex_lock_interruptible(lock) mutex_lock_interruptible_nested(loc= k, 0) @@ -211,10 +212,10 @@ do { \ _mutex_lock_killable(lock, subclass, NULL) =20 #else -extern void mutex_lock(struct mutex *lock); -extern int __must_check mutex_lock_interruptible(struct mutex *lock); -extern int __must_check mutex_lock_killable(struct mutex *lock); -extern void mutex_lock_io(struct mutex *lock); +extern void mutex_lock(struct mutex *lock) __acquires(lock); +extern int __must_check mutex_lock_interruptible(struct mutex *lock) __con= d_acquires(0, lock); +extern int __must_check mutex_lock_killable(struct mutex *lock) __cond_acq= uires(0, lock); +extern void mutex_lock_io(struct mutex *lock) __acquires(lock); =20 # define mutex_lock_nested(lock, subclass) mutex_lock(lock) # define mutex_lock_interruptible_nested(lock, subclass) mutex_lock_interr= uptible(lock) @@ -232,7 +233,7 @@ extern void mutex_lock_io(struct mutex *lock); */ =20 #ifdef CONFIG_DEBUG_LOCK_ALLOC -extern int _mutex_trylock_nest_lock(struct mutex *lock, struct lockdep_map= *nest_lock); +extern int _mutex_trylock_nest_lock(struct mutex *lock, struct lockdep_map= *nest_lock) __cond_acquires(true, lock); =20 #define mutex_trylock_nest_lock(lock, nest_lock) \ ( \ @@ -242,17 +243,24 @@ extern int _mutex_trylock_nest_lock(struct mutex *loc= k, struct lockdep_map *nest =20 #define mutex_trylock(lock) _mutex_trylock_nest_lock(lock, NULL) #else -extern int mutex_trylock(struct mutex *lock); +extern int mutex_trylock(struct mutex *lock) __cond_acquires(true, lock); #define mutex_trylock_nest_lock(lock, nest_lock) mutex_trylock(lock) #endif =20 -extern void mutex_unlock(struct mutex *lock); +extern void mutex_unlock(struct mutex *lock) __releases(lock); =20 -extern int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock); +extern int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock) __= cond_acquires(true, lock); =20 -DEFINE_GUARD(mutex, struct mutex *, mutex_lock(_T), mutex_unlock(_T)) -DEFINE_GUARD_COND(mutex, _try, mutex_trylock(_T)) -DEFINE_GUARD_COND(mutex, _intr, mutex_lock_interruptible(_T), _RET =3D=3D = 0) +DEFINE_LOCK_GUARD_1(mutex, struct mutex, mutex_lock(_T->lock), mutex_unloc= k(_T->lock)) +DEFINE_LOCK_GUARD_1_COND(mutex, _try, mutex_trylock(_T->lock)) +DEFINE_LOCK_GUARD_1_COND(mutex, _intr, mutex_lock_interruptible(_T->lock),= _RET =3D=3D 0) + +DECLARE_LOCK_GUARD_1_ATTRS(mutex, __acquires(_T), __releases(*(struct mute= x **)_T)) +#define class_mutex_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(mutex, _T) +DECLARE_LOCK_GUARD_1_ATTRS(mutex_try, __acquires(_T), __releases(*(struct = mutex **)_T)) +#define class_mutex_try_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(mutex_try,= _T) +DECLARE_LOCK_GUARD_1_ATTRS(mutex_intr, __acquires(_T), __releases(*(struct= mutex **)_T)) +#define class_mutex_intr_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(mutex_int= r, _T) =20 extern unsigned long mutex_get_owner(struct mutex *lock); =20 diff --git a/include/linux/mutex_types.h b/include/linux/mutex_types.h index fdf7f515fde8..80975935ec48 100644 --- a/include/linux/mutex_types.h +++ b/include/linux/mutex_types.h @@ -38,7 +38,7 @@ * - detects multi-task circular deadlocks and prints out all affected * locks and tasks (and only those tasks) */ -struct mutex { +context_lock_struct(mutex) { atomic_long_t owner; raw_spinlock_t wait_lock; #ifdef CONFIG_MUTEX_SPIN_ON_OWNER @@ -59,7 +59,7 @@ struct mutex { */ #include =20 -struct mutex { +context_lock_struct(mutex) { struct rt_mutex_base rtmutex; #ifdef CONFIG_DEBUG_LOCK_ALLOC struct lockdep_map dep_map; diff --git a/lib/test_context-analysis.c b/lib/test_context-analysis.c index 273fa9d34657..2b28d20c5f51 100644 --- a/lib/test_context-analysis.c +++ b/lib/test_context-analysis.c @@ -5,6 +5,7 @@ */ =20 #include +#include #include =20 /* @@ -144,3 +145,66 @@ TEST_SPINLOCK_COMMON(read_lock, read_unlock, read_trylock, TEST_OP_RO); + +struct test_mutex_data { + struct mutex mtx; + int counter __guarded_by(&mtx); +}; + +static void __used test_mutex_init(struct test_mutex_data *d) +{ + mutex_init(&d->mtx); + d->counter =3D 0; +} + +static void __used test_mutex_lock(struct test_mutex_data *d) +{ + mutex_lock(&d->mtx); + d->counter++; + mutex_unlock(&d->mtx); + mutex_lock_io(&d->mtx); + d->counter++; + mutex_unlock(&d->mtx); +} + +static void __used test_mutex_trylock(struct test_mutex_data *d, atomic_t = *a) +{ + if (!mutex_lock_interruptible(&d->mtx)) { + d->counter++; + mutex_unlock(&d->mtx); + } + if (!mutex_lock_killable(&d->mtx)) { + d->counter++; + mutex_unlock(&d->mtx); + } + if (mutex_trylock(&d->mtx)) { + d->counter++; + mutex_unlock(&d->mtx); + } + if (atomic_dec_and_mutex_lock(a, &d->mtx)) { + d->counter++; + mutex_unlock(&d->mtx); + } +} + +static void __used test_mutex_assert(struct test_mutex_data *d) +{ + lockdep_assert_held(&d->mtx); + d->counter++; +} + +static void __used test_mutex_guard(struct test_mutex_data *d) +{ + guard(mutex)(&d->mtx); + d->counter++; +} + +static void __used test_mutex_cond_guard(struct test_mutex_data *d) +{ + scoped_cond_guard(mutex_try, return, &d->mtx) { + d->counter++; + } + scoped_cond_guard(mutex_intr, return, &d->mtx) { + d->counter++; + } +} --=20 2.52.0.322.g1dd061c0dc-goog