Re: [PATCH for-5.0 v5 15/23] ppc/xive: Use the XiveFabric and XivePresenter interfaces

[Greg Kurz <groug@kaod.org>]

On Thu, 21 Nov 2019 08:40:32 +0100
Cédric Le Goater <clg@kaod.org> wrote:

> On 21/11/2019 08:30, Greg Kurz wrote:
> > On Thu, 21 Nov 2019 08:01:44 +0100
> > Cédric Le Goater <clg@kaod.org> wrote:
> > 
> >> On 20/11/2019 19:30, Greg Kurz wrote:
> >>> On Fri, 15 Nov 2019 17:24:28 +0100
> >>> Cédric Le Goater <clg@kaod.org> wrote:
> >>>
> >>>> Now that the machines have handlers implementing the XiveFabric and
> >>>> XivePresenter interfaces, remove xive_presenter_match() and make use
> >>>> of the 'match_nvt' handler of the machine.
> >>>>
> >>>> Signed-off-by: Cédric Le Goater <clg@kaod.org>
> >>>> ---
> >>>>  hw/intc/xive.c | 48 +++++++++++++++++-------------------------------
> >>>>  1 file changed, 17 insertions(+), 31 deletions(-)
> >>>>
> >>>
> >>> Nice diffstat :)
> >>>
> >>>> diff --git a/hw/intc/xive.c b/hw/intc/xive.c
> >>>> index 1c9e58f8deac..ab62bda85788 100644
> >>>> --- a/hw/intc/xive.c
> >>>> +++ b/hw/intc/xive.c
> >>>> @@ -1423,30 +1423,6 @@ int xive_presenter_tctx_match(XivePresenter *xptr, XiveTCTX *tctx,
> >>>>      return -1;
> >>>>  }
> >>>>  
> >>>> -static bool xive_presenter_match(XiveRouter *xrtr, uint8_t format,
> >>>> -                                 uint8_t nvt_blk, uint32_t nvt_idx,
> >>>> -                                 bool cam_ignore, uint8_t priority,
> >>>> -                                 uint32_t logic_serv, XiveTCTXMatch *match)
> >>>> -{
> >>>> -    XivePresenter *xptr = XIVE_PRESENTER(xrtr);
> >>>> -    XivePresenterClass *xpc = XIVE_PRESENTER_GET_CLASS(xptr);
> >>>> -    int count;
> >>>> -
> >>>> -    count = xpc->match_nvt(xptr, format, nvt_blk, nvt_idx, cam_ignore,
> >>>> -                           priority, logic_serv, match);
> >>>> -    if (count < 0) {
> >>>> -        return false;
> >>>> -    }
> >>>> -
> >>>> -    if (!match->tctx) {
> >>>> -        qemu_log_mask(LOG_UNIMP, "XIVE: NVT %x/%x is not dispatched\n",
> >>>> -                      nvt_blk, nvt_idx);
> >>>
> >>> Maybe keep this trace...
> >>
> >> It's in spapr_xive_match_nvt() now.
> >>
> > 
> > Not really... spapr_xive_match_nvt() has a trace for the opposite case of duplicate
> > matches:
> 
> not that one. The one in spapr.c ... Yes I need to change the name.
> 

... and it seems I cannot memorize a change that was made by the
previous patch :-\ Sorry for the noise.

With or without the !!count change:

Reviewed-by: Greg Kurz <groug@kaod.org>

> C.
> 
> > 
> >             if (match->tctx) {
> >                 qemu_log_mask(LOG_GUEST_ERROR, "XIVE: already found a thread "
> >                               "context NVT %x/%x\n", nvt_blk, nvt_idx);
> >                 return -1;
> >             }
> > 
> >>>
> >>>> -        return false;
> >>>> -    }
> >>>> -
> >>>> -    return true;
> >>>> -}
> >>>> -
> >>>>  /*
> >>>>   * This is our simple Xive Presenter Engine model. It is merged in the
> >>>>   * Router as it does not require an extra object.
> >>>> @@ -1462,22 +1438,32 @@ static bool xive_presenter_match(XiveRouter *xrtr, uint8_t format,
> >>>>   *
> >>>>   * The parameters represent what is sent on the PowerBus
> >>>>   */
> >>>> -static bool xive_presenter_notify(XiveRouter *xrtr, uint8_t format,
> >>>> +static bool xive_presenter_notify(uint8_t format,
> >>>>                                    uint8_t nvt_blk, uint32_t nvt_idx,
> >>>>                                    bool cam_ignore, uint8_t priority,
> >>>>                                    uint32_t logic_serv)
> >>>>  {
> >>>> +    XiveFabric *xfb = XIVE_FABRIC(qdev_get_machine());
> >>>> +    XiveFabricClass *xfc = XIVE_FABRIC_GET_CLASS(xfb);
> >>>>      XiveTCTXMatch match = { .tctx = NULL, .ring = 0 };
> >>>> -    bool found;
> >>>> +    int count;
> >>>>  
> >>>> -    found = xive_presenter_match(xrtr, format, nvt_blk, nvt_idx, cam_ignore,
> >>>> -                                 priority, logic_serv, &match);
> >>>> -    if (found) {
> >>>> +    /*
> >>>> +     * Ask the machine to scan the interrupt controllers for a match
> >>>> +     */
> >>>> +    count = xfc->match_nvt(xfb, format, nvt_blk, nvt_idx, cam_ignore,
> >>>> +                           priority, logic_serv, &match);
> >>>> +    if (count < 0) {
> >>>> +        return false;
> >>>> +    }
> >>>> +
> >>>> +    /* handle CPU exception delivery */
> >>>> +    if (count) {
> >>>>          ipb_update(&match.tctx->regs[match.ring], priority);
> >>>>          xive_tctx_notify(match.tctx, match.ring);
> >>>>      }
> >>>
> >>> ... in an else block here ^^ ?
> >>>
> >>>>  
> >>>> -    return found;
> >>>> +    return count;
> >>>
> >>> Implicit cast is ok I guess, but !!count would ensure no paranoid
> >>> compiler ever complains.
> >>
> >> yes. 
> >>
> >> Thanks,
> >>
> >> C.
> >>
> >>
> >>>
> >>>>  }
> >>>>  
> >>>>  /*
> >>>> @@ -1590,7 +1576,7 @@ static void xive_router_end_notify(XiveRouter *xrtr, uint8_t end_blk,
> >>>>          return;
> >>>>      }
> >>>>  
> >>>> -    found = xive_presenter_notify(xrtr, format, nvt_blk, nvt_idx,
> >>>> +    found = xive_presenter_notify(format, nvt_blk, nvt_idx,
> >>>>                            xive_get_field32(END_W7_F0_IGNORE, end.w7),
> >>>>                            priority,
> >>>>                            xive_get_field32(END_W7_F1_LOG_SERVER_ID, end.w7));
> >>>
> >>
> > 
>