Re: [Qemu-devel] [PATCH v2 1/2] ps2: add support of auto-repeat

[Amos Kong <akong@redhat.com>]

On Fri, May 31, 2013 at 08:31:17PM +0800, Amos Kong wrote:
> On Thu, May 30, 2013 at 11:48:46AM -0500, Anthony Liguori wrote:
> > Amos Kong <akong@redhat.com> writes:
> > 
> > > Guest driver sets repeat rate and delay time by KBD_CMD_SET_RATE,
> > > but ps2 backend doesn't process it and no auto-repeat implementation.
> > > This patch adds support of auto-repeat feature. The repeated events
> > > from host are ignored and re-implements ps2's auto-repeat.
> > >
> > > Guest ps2 driver sets autorepeat to fastest possible in reset,
> > > period: 250ms, delay: 33ms
> > >
> > > Tested by 'sendkey' monitor command.
> > > Tested by Linux & Windows guests with SDL, VNC, SPICE, GTK+
> > >
> > > referenced: http://www.computer-engineering.org/ps2keyboard/
> > >
> > > Signed-off-by: Amos Kong <akong@redhat.com>
> > > ---
> > >  hw/input/ps2.c | 41 +++++++++++++++++++++++++++++++++++++++++
> > >  1 file changed, 41 insertions(+)
> > >
> > > diff --git a/hw/input/ps2.c b/hw/input/ps2.c
> > > index 3412079..8adbb4a 100644
> > > --- a/hw/input/ps2.c
> > > +++ b/hw/input/ps2.c
> > > @@ -94,6 +94,10 @@ typedef struct {
> > >      int translate;
> > >      int scancode_set; /* 1=XT, 2=AT, 3=PS/2 */
> > >      int ledstate;
> > > +    int repeat_period; /* typematic period, ms */
> > > +    int repeat_delay; /* typematic delay, ms */
> > > +    int repeat_key; /* keycode to repeat */
> > > +    QEMUTimer *repeat_timer;
> > 
> > This state needs to be migrated, no?  I suspect it can/should be done
> > via a subsection too.
> 
> It sounds only reasonable for 'sendkey' command. We want to repeat one
> key for 100 times, the key should be continaully repeated in the dest
> vm until it reaches to 100 times.
> 
> For implement this, we should also migrate key_timer in ui/input.c,
> then it will send a release event to ps2 queue when the key_timer
> is expired. The bottom patch migrates repeat_timer & repeat_key,
> where should we save key_timer for migration?
> 
> ----
> 
> For the VNC/SPICE/SDL/GTK+ windows, qemu gets repeated press events
> from host. After vm migrates to dest host, if we don't touch the
> keyboard, there will be no repeat / release event comes from host,
> 
> 1) continue to repeat? but qemu no long gets press event from host
> 2) stop to repeat? but qemu has not got the release event, auto-repeat
> should continue in real keyboard in this condition.
> 
> I prefect 2), because we need to emulate a release event in the
> prepare stage of migrate.
> 
> For implement 2), we should not load/restart the repeat_timer if
> the migrated key_timer is already expired.
> 
> ---
> 
> Or just migrate the repeat_rate/repeat_period. We don't have
> real request of auto-repeat in libvirt.
> 
> This might be the best solution as Paolo said ;)
> http://lists.nongnu.org/archive/html/qemu-devel/2013-05/msg02207.html
 
ping Anthony, Paolo

I don't think we need to migrate the repeat timer/state.
only need to migrate related setup (rate/delay) as in last patch.

If you agree with this, I can merge those to patches together for
avoiding to break the bisect.
 
Amos.

> diff --git a/hw/input/ps2.c b/hw/input/ps2.c
> index cdb18e6..fdb9912 100644
> --- a/hw/input/ps2.c
> +++ b/hw/input/ps2.c
> @@ -615,7 +615,17 @@ static bool ps2_keyboard_repeatstate_needed(void
> *opaque)
>  {
>      PS2KbdState *s = opaque;
>  
> -    return s->repeat_period || s->repeat_delay;
> +    return s->repeat_period || s->repeat_delay || s->repeat_key ||
> s->repeat_timer;
> +}
> +
> +static int ps2_kbd_repeatstate_load(QEMUFile *f, void *opaque, int
> version_id)
> +{
> +    PS2KbdState *s = opaque;
> +    qemu_get_timer(f, s->repeat_timer);
> +    qemu_mod_timer(s->repeat_timer, qemu_get_clock_ns(vm_clock) +
> +                   muldiv64(get_ticks_per_sec(), s->repeat_period,
> 1000));
> +
> +    return 0;
>  }
>  
>  static bool ps2_keyboard_ledstate_needed(void *opaque)
> @@ -638,9 +648,12 @@ static const VMStateDescription
> vmstate_ps2_keyboard_repeatstate = {
>      .version_id = 3,
>      .minimum_version_id = 2,
>      .minimum_version_id_old = 2,
> +    .load_state_old = ps2_kbd_repeatstate_load,
>      .fields      = (VMStateField[]) {
>          VMSTATE_INT32(repeat_period, PS2KbdState),
>          VMSTATE_INT32(repeat_delay, PS2KbdState),
> +        VMSTATE_INT32(repeat_key, PS2KbdState),
> +        VMSTATE_TIMER(repeat_timer, PS2KbdState),
>          VMSTATE_END_OF_LIST()
>      }
>  };
>