On Tue, Sep 14, 2010 at 10:43 PM, Bond <jamesbond.2k.g@xxxxxxxxx> wrote: > > > On Tue, Sep 14, 2010 at 10:31 PM, Greg Freemyer <greg.freemyer@xxxxxxxxx> > wrote: >> >> I think a mutex will do what you need. >> Have you looked at: Documentation/mutex-design.txt >> >> You should find the Documentation folder at the top level of your >> kernel source tree. >> >> The mutex calls are at the bottom of the file. >> > Ok. >> >> Look around at the kernel source for some example uses. Especially >> where to call mutex_init(). You obviously don't want to call that in >> your write() routine. >> > Why not in write routine? > I discussed this thing with a friend he suggested to implement this in write > routine() . mutex_init() is a way to dynamically _create_ a mutex. I'm sure you can do that in the write routine, but it seems much more natural to create your control mutex in the open routine since it is effectively a one time action. fyi: your driver may be so simple you don't need to create the mutex dynamically. See LLD3 chapter 5 for more: http://lwn.net/images/pdf/LDD3/ch05.pdf Greg -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
