Where did init_MUTEX go to linux kernel version 3.2?

Question

I am following Linux Device Drivers (3rd Edition). When I try to emulate the skull example in chapter 6, an error is reported. It says that:

    error: implicit declaration of function ‘init_MUTEX’ [-Werror=implicit-function-declaration]

Can anyone tell me where init_MUTEX went? By the way, is there a list where I can check all the kernel API changes?

+3

Douglas Su 06 jan. 15 at 15:13

2 answers

Use mutex_init () instead:

struct scull_pipe {
    ...
    struct mutex mutex;
    ...
};

mutex_init(&(lptr->device.mutex));

+2

CL. 06 jan. 15 at 19:53

askb · Accepted Answer · 2015-01-06T15:58:43+0000

init_MUTEX{_LOCKED}()

was originally implemented as a semaphore . Semaphores were only in older 2.6.16 kernels, now replaces the mutex using earlier semaphores, check the bottom api header andlinux/mutex.h

struct mutex { ...
};

mutex_{init,lock,trylock,unlock,lock_interruptible}()