On Tue, 26 Nov 2019 07:13:55 +0900, Richard Weinberger wrote: > > On Fri, Nov 8, 2019 at 6:03 AM Hajime Tazaki <thehajime@xxxxxxxxx> wrote: > > > > From: Octavian Purdila <tavi.purdila@xxxxxxxxx> > > > > Add APIs that allows the host to reserve and free and interrupt number > > and also to trigger an interrupt. > > > > The trigger operation will simply store the interrupt data in > > queue. The interrupt handler is run later, at the first opportunity it > > has to avoid races with any kernel threads. > > > > Currently, interrupts are run on the first interrupt enable operation > > if interrupts are disabled and if we are not already in interrupt > > context. > > > > When triggering an interrupt, it uses GCC's built-in functions for > > atomic memory access to synchronize and simple boolean flags. > > > > Signed-off-by: Hajime Tazaki <thehajime@xxxxxxxxx> > > Signed-off-by: Michael Zimmermann <sigmaepsilon92@xxxxxxxxx> > > Signed-off-by: Octavian Purdila <tavi.purdila@xxxxxxxxx> > > --- > > arch/um/lkl/include/asm/irq.h | 13 ++ > > arch/um/lkl/include/uapi/asm/irq.h | 36 ++++ > > arch/um/lkl/include/uapi/asm/sigcontext.h | 16 ++ > > arch/um/lkl/kernel/irq.c | 193 ++++++++++++++++++++++ > > Like I said before, this also something to unify with UML. > I'm aware that this is easily said but we cannot have too much duplication. > > Feel free to ask if UML internals give you headache. :-) Same as nommu implementation, I left this part as-is. Triggering interrupts with fd events (delivered by epoll&co) is a hard part to implement host-independent interrupts of LKL. OTOH, the v3 patchset shows that it is doable to use UML drivers with the LKL interrupt facility. I may also need more time to evaluate/find a right direction, though. Your comments are always welcome. -- Hajime
