What is the use of downgrade_write(struct rw_semaphore *sem)?
I am aware of how semaphores work. We can hold the rwsemaphore for writing the shared data structure using down_write and down_write_trylock and release the semaphore using up_write. Why do we need to use downgrade_write()? What is the difference between down_write() and downgrade_write()?
semaphore
asked Nov 14 '18 at 5:51
AkibAkib
132
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I am aware of how semaphores work. We can hold the rwsemaphore for writing the shared data structure using down_write and down_write_trylock and release the semaphore using up_write. Why do we need to use downgrade_write()? What is the difference between down_write() and downgrade_write()?
semaphore
asked Nov 14 '18 at 5:51
AkibAkib
132
add a comment |
I am aware of how semaphores work. We can hold the rwsemaphore for writing the shared data structure using down_write and down_write_trylock and release the semaphore using up_write. Why do we need to use downgrade_write()? What is the difference between down_write() and downgrade_write()?
semaphore
asked Nov 14 '18 at 5:51
AkibAkib
132
I am aware of how semaphores work. We can hold the rwsemaphore for writing the shared data structure using down_write and down_write_trylock and release the semaphore using up_write. Why do we need to use downgrade_write()? What is the difference between down_write() and downgrade_write()?
semaphore
semaphore
asked Nov 14 '18 at 5:51
AkibAkib
132
asked Nov 14 '18 at 5:51
AkibAkib
132
asked Nov 14 '18 at 5:51
AkibAkib
132
asked Nov 14 '18 at 5:51
AkibAkib
132
asked Nov 14 '18 at 5:51
AkibAkib
132
132
add a comment |
add a comment |
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