| Message ID | 20240905204709.556577-3-bvanassche@acm.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | e837d833a13461c10f265a65ce6612e6dd43e76f |
| Headers | show |
| Series | Fix a lockdep complaint related to USB role switching | expand |
On Thu, Sep 5, 2024 at 11:47 PM Bart Van Assche <bvanassche@acm.org> wrote: > > The following pattern occurs 5 times in kernel drivers: > > lockdep_register_key(key); > __mutex_init(mutex, name, key); > > In several cases the 'name' argument matches #mutex. Hence, introduce > the mutex_init_with_key() macro. This macro derives the 'name' argument > from the 'mutex' argument. FWIW, Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
diff --git a/include/linux/mutex.h b/include/linux/mutex.h index ef617089db19..2bf91b57591b 100644 --- a/include/linux/mutex.h +++ b/include/linux/mutex.h @@ -64,6 +64,17 @@ do { \ __mutex_init((mutex), #mutex, &__key); \ } while (0) +/** + * mutex_init_with_key - initialize a mutex with a given lockdep key + * @mutex: the mutex to be initialized + * @key: the lockdep key to be associated with the mutex + * + * Initialize the mutex to the unlocked state. + * + * It is not allowed to initialize an already locked mutex. + */ +#define mutex_init_with_key(mutex, key) __mutex_init((mutex), #mutex, (key)) + #ifndef CONFIG_PREEMPT_RT #define __MUTEX_INITIALIZER(lockname) \ { .owner = ATOMIC_LONG_INIT(0) \
The following pattern occurs 5 times in kernel drivers: lockdep_register_key(key); __mutex_init(mutex, name, key); In several cases the 'name' argument matches #mutex. Hence, introduce the mutex_init_with_key() macro. This macro derives the 'name' argument from the 'mutex' argument. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Bart Van Assche <bvanassche@acm.org> --- include/linux/mutex.h | 11 +++++++++++ 1 file changed, 11 insertions(+)