From: kernelnewbies-bounce@xxxxxxxxxxxx 代理 Rajat Jain
Sent: 4/11/2007 (水) 10:18 午前
To: pradeep singh
Cc: kernelnewbies@xxxxxxxxxxxxxxxxx
Subject: Re: recursive locks in linux
On 4/11/07, pradeep singh <2500.pradeep@xxxxxxxxx>
wrote:
> Hi All,
> This may sound stupid but how can i implement a
recursive lock in Linux kernel?
> I guess Mutex and semaphores
cannot be used.
>
> Spinlocks can be i guess.
> Can somebody
give me some pointers or links for this?
> Googling didn't help
much.
Spinlocks, semaphores & Mutexes defnitely can't be
used.
Although the RW semaphores and RW spinlocks allow recursive
locking
(since multiple threads can simultaneously hold reader
locks).
--------------- response from Gaurav Dhiman starts -----------------------
Rajat read-write locks are not recursive in nature, as the same thread can not again acquire the lock once it has already acquired the lock. There are no recursive lock avaialble and should not be avialable, as recursive locks lead to deadlock. When thread tries to acquire the lock for second time recursively, it will be put on hold or spin forever waiting for the lock to be release which the thread has itself acquired, leading it to deadlock.
regards,
Gaurav
Just curious, why do you need
it?
Thanks,
Rajat
>
> Thank
you
>
> ~psr
>
> --
> play the
game
>
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