Init_mutex is abolished (resolves error:implicit declaration of function ' Init_mutex ')

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Init_mutex was abolished Resolve Error:implicit declaration of function ' Init_mutex '	Ldd/problem/port/init_mutex

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1 Questions

The following error was prompted during the recent migration drive

Error:implicit declaration of function ' Init_mutex ' [-werror=implicit-function-declaration] 2 causal analysis

In the Linux kernel after 2.6.37, Init_mutex has been abolished and the new version uses the Sema_init function

Check out the definition of an earlier version, see Include/linux/semaphore.h, Version 2.6.36.4, line 42

static inline void Sema_init (struct semaphore *sem, int val)
{
    static struct lock_class_key;
    *sem = (struct semaphore) __semaphore_initializer (*sem, Val);
    Lockdep_init_map (&sem->lock.dep_map, "Semaphore->lock", &__key, 0);
}

#define INIT_MUTEX (SEM)     sema_init (SEM, 1)
#define INIT_MUTEX_LOCKED (SEM)  sema_init (SEM, 0)

3 Solutions

Modify the Init_mutex to Sema_init, or you can define Init_mutex modifications in the drive Init_mutex for Sema_init

#if linux_version_code > Kernel_version (2, 6,) &&!defined (Init_mutex)
    sema_init (&sem, 1);
#else
    Init_mutex (&sem);
#endif

Define Init_mutex as Sema_init

#if linux_version_code > Kernel_version (2, 6) &&!defined (Init_mutex)
#define INIT_MUTEX (SEM)     sema_init (SEM, 1)
#endif

In fact, in the early kernel, the definition of sema_init, so you can not need to add #if #endif macros, directly modify Init_mutex for Sema_init is not a problem.

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