Re: [Qemu-devel] [PATCH v1 for-2-12 09/15] s390x/tcg: implement TEST PENDING INTERRUPTION

[Cornelia Huck <cohuck@redhat.com>]

On Mon, 11 Dec 2017 21:32:58 +0100
David Hildenbrand <david@redhat.com> wrote:

> On 11.12.2017 19:01, Cornelia Huck wrote:
> > On Mon, 11 Dec 2017 14:47:34 +0100
> > David Hildenbrand <david@redhat.com> wrote:
> >   
> >> Use s390_cpu_virt_mem_write() so we can actually revert what we did
> >> (re-inject the dequeued IO interrupt).
> >>
> >> Signed-off-by: David Hildenbrand <david@redhat.com>
> >> ---
> >>  target/s390x/helper.h      |  1 +
> >>  target/s390x/insn-data.def |  1 +
> >>  target/s390x/misc_helper.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++
> >>  target/s390x/translate.c   |  8 +++++++
> >>  4 files changed, 63 insertions(+)
> >>  
> >   
> >> +uint32_t HELPER(tpi)(CPUS390XState *env, uint64_t addr)
> >> +{
> >> +    const uintptr_t ra = GETPC();
> >> +    S390CPU *cpu = s390_env_get_cpu(env);
> >> +    QEMUS390FLICState *flic = QEMU_S390_FLIC(s390_get_flic());
> >> +    QEMUS390FlicIO *io = NULL;
> >> +    LowCore *lowcore;
> >> +
> >> +    if (addr & 0x3) {
> >> +        s390_program_interrupt(env, PGM_SPECIFICATION, 4, ra);
> >> +    }
> >> +
> >> +    qemu_mutex_lock_iothread();
> >> +    io = qemu_s390_flic_dequeue_io(flic, env->cregs[6]);
> >> +    if (!io) {
> >> +        qemu_mutex_unlock_iothread();
> >> +        return 0;
> >> +    }
> >> +
> >> +    if (addr) {
> >> +        struct {
> >> +            uint16_t id;
> >> +            uint16_t nr;
> >> +            uint32_t parm;
> >> +        } tmp = {
> >> +            .id = cpu_to_be16(io->id),
> >> +            .nr = cpu_to_be16(io->nr),
> >> +            .parm = cpu_to_be32(io->parm),
> >> +        };  
> > 
> > That's a two-word interruption code; can you call this something better
> > than 'tmp'?  
> 
> IMHO from the context we have here it should be pretty clear what is
> happening. I mean we are defining and initializing the temporary data
> structure.
> 
> But I can change the name if you can come up with a catchy variable name. :)
> 

int_code?