On Fri, Aug 29, 2025 at 11:57 PM Richard Henderson
<richard.hender...@linaro.org> wrote:
>
> On 8/30/25 01:31, Paolo Bonzini wrote:
> > @@ -624,8 +624,7 @@ static target_ulong h_confer(PowerPCCPU *cpu,
> > SpaprMachineState *spapr,
> > }
> >
> > cs->exception_index = EXCP_YIELD;
> > - qatomic_set(&cs->exit_request, true);
> > - cpu_loop_exit(cs);
> > + cpu_exit(cs);
> >
> > return H_SUCCESS;
> > }
>
> cpu_loop_exit does a longjmp; cpu_exit does not.
>
> This may be a bug fix, but it's hard to tell.
> If it is a bug fix, it should be separated.
The longjmp is overkill but works. Not doing the longjmp also works
because gen_sc() finishes the TB and then you go all the way (check
interrupt_request -> check exit_request -> write exception_index ->
cpu_exec_end) out of tcg_cpu_exec().
I like cpu_loop_exit() to signify that I am in the middle of the TB.
That said, I'm always conflicted between renaming badly-named
functions and keeping historical names. qemu_wait_io_event() is also
horrible.
> > +++ b/system/cpu-timers.c
> > @@ -246,14 +246,14 @@ void qemu_timer_notify_cb(void *opaque, QEMUClockType
> > type)
> >
> > if (qemu_in_vcpu_thread()) {
> > /*
> > - * A CPU is currently running; kick it back out to the
> > + * A CPU is currently running; kick it back out of the
> > * tcg_cpu_exec() loop so it will recalculate its
> > * icount deadline immediately.
> > */
> > - qemu_cpu_kick(current_cpu);
> > + cpu_exit(current_cpu);
>
> where the comment still says kick and we're replacing kick with exit.
>
> I guess the root of this problem is that "kick" isn't a precise term, we
> ought to name it
> something else, and we should paint the bike shed green.
Yes, I agree. "send it out of" can work too in this case, I'll chanbge it.
Paolo
