Semaphore

[Rajath N R]

Hi,
    Once process terminated for what ever reason, kernel should release all
the resources held by that process including lock.
do_exit()-->exit_sem().

thanks,
Rajath
On Tue, Feb 28, 2012 at 1:53 PM, Rajath N R <rajathnr at gmail.com> wrote:

> Hi,
>     I think santosh is talking about user land IPC (semget).
> thread/process which has acquired a sema lock/sem down using semop(2)
> syscall.
>
>
>
> Thanks,
> Rajath
>
>
> On Fri, Feb 24, 2012 at 3:54 PM, Kristof Provost <kristof at sigsegv.be>wrote:
>
>> On 2012-02-24 12:15:03 (+0200), Kosta Zertsekel <zertsekel at gmail.com>
>> wrote:
>> > I think of user land program opening a socket and crashing on
>> > segmentation fault.
>> > In code 'socket' syscall does:
>> >     sock_map_fd --> sock_alloc_file --> alloc_file --> ... get lost ...
>> > Where exactly in this case lock is held - I mean the lock that gets
>> > released when user land process dies?
>>
>> In this case there doesn't appear to be any lock. The sock_map_fd
>> function is most probably called from the socket syscall. This call
>> isn't locked. Multiple processes can be in the socket syscall at the
>> same time.
>> There certainly won't be a (kernel) lock which is held between two system
>> calls.
>>
>> Regards,
>> Kristof
>>
>>
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>
>
>
> --
> Thanks & Regards,
> Rajath N R
>



-- 
Thanks & Regards,
Rajath N R
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