A few of the mutex APIs are provided below
| #define mutex_init(mutex) | Initialize the mutex to unlocked state. This Macro invokes the function __mutex_init |
| void __sched mutex_lock(struct mutex *lock) | Acquire the lock |
| void __sched mutex_unlock(struct mutex *lock) | Release the Mutex |
| int __sched mutex_lock_interruptible(struct mutex *lock) | Acquire the Mutex, interruptible by signals. If a signal is delivered while the process is sleeping, this function will return without acquiring the Mutex |
| int __sched mutex_lock_killable(struct mutex *lock) | Acquire the mutex, interruptible by fatal signals. If a signal which will be fatal to the current process is delivered while the process is sleeping, this function will return without acquiring the mutex. |
| int __sched mutex_trylock(struct mutex *lock) | try to acquire the mutex, without waitingTry to acquire the mutex atomically. Returns 1 if the mutex has been acquired successfully, and 0 on contention. |
| int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock) | return holding mutex if we dec to 0return true and hold lock if we dec to 0, return false otherwise |
A sample code showing the usage of static and dynamic allocation mechanisms for the Mutex API is provided below
Static Mutex example code:
Dynamic Mutex example code:
Semaphores in the Linux Kernel
- References
- https://elixir.bootlin.com/linux/latest/source/kernel/locking/mutex.c#L279
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