2009/9/18 Leonidas . <leonidas137@xxxxxxxxx>: > > > On Thu, Sep 17, 2009 at 9:43 PM, Michael Blizek > <michi1@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote: >> >> Hi! >> >> On 17:20 Thu 17 Sep , Leonidas . wrote: >> > Hi List, >> > >> > I am aware of the fact that in interrupt context one should not use >> > mutexes/semaphore >> > and should stick to spinlocks. >> >> Yes, exactly. >> >> > I am developing a module which exposes interfaces which could be called >> > from >> > any/all >> > contexts. And I manipulate complex data structures in my functions. >> > Being on >> > safer side >> > I should stick to spinlocks. But in most of the cases it would not be >> > needed, meaning my >> > functions would get called mostly from process contexts, so spinlocks >> > sounds >> > wasteful >> > since my critical sections are long and painful. >> >> Is there any way to view your code? >> >> 1) Executing long functions in interrupt context is bad, because this >> introduces latencies into the system. Try to put at least the big >> functions >> into a workqueue. >> >> 2) You can try to remove the locking outside of this module and make it >> the >> responsibility of the module user. >> >> -Michi >> -- >> programing a layer 3+4 network protocol for mesh networks >> see http://michaelblizek.twilightparadox.com >> > > Michi, > > Actually, I have not written any code yet, just pondering over design as of > now. > Would start writing only once some of these rough edges are sorted out. > > Yes, I should ideally move out the big functions outside ISRs, but issue > with my > module is, I would not know from where I am getting called. My module will > just > export apis which modules can call from whereever they want, and I cant put > it > as a constraint that they should not call from ISRs, my module is going to > be bit > like profiling module so a user might actually want to call it from ISR to > profile it. > > > Can I do following? > As soon as I enter my functions, I check whether I am running in interupt > context > or process context and spwan a tasklet/workqueue if I am in interrupt > context or proceed in the > same function if I am in process context. This would make more sense right? > This problem is so weird i think. why u need do this check. And you design your functions and why not know the code run in which level ? linux is totally opensouce and transparent for programmers. > But above point does not solve the locking issue? Does it? And I can't move > locking outside > my module and ask user to do so since that might not be possible. I want my > module to be > as reentrant as possible without making user do too many things. > > > -Leo. > > > > -- Best Regards Lin -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
