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

[Greg Kurz]

On Thu, 21 Nov 2019 10:22:38 +0100
Cédric Le Goater <address@hidden> wrote:

> On 21/11/2019 09:08, Greg Kurz wrote:
> > On Thu, 21 Nov 2019 08:40:32 +0100
> > Cédric Le Goater <address@hidden> wrote:
> > 
> >> On 21/11/2019 08:30, Greg Kurz wrote:
> >>> On Thu, 21 Nov 2019 08:01:44 +0100
> >>> Cédric Le Goater <address@hidden> wrote:
> >>>
> >>>> On 20/11/2019 19:30, Greg Kurz wrote:
> >>>>> On Fri, 15 Nov 2019 17:24:28 +0100
> >>>>> Cédric Le Goater <address@hidden> 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 <address@hidden>
> >>>>>> ---
> >>>>>>  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.
> 
> np but this is problem for gdb ! Any suggestion on the name : 
> 
>    spapr_match_nvt() 
> 

I guess having nvt in the name is enough to identify this as
a XIVE related function. It's ok for me.

BTW, the same problem exists in powernv:

$ git grep pnv_xive_match_nvt
hw/intc/pnv_xive.c:static int pnv_xive_match_nvt(XivePresenter *xptr, uint8_t 
format,
hw/intc/pnv_xive.c:    xpc->match_nvt  = pnv_xive_match_nvt;
hw/ppc/pnv.c:static int pnv_xive_match_nvt(XiveFabric *xfb, uint8_t format,
hw/ppc/pnv.c:    xfc->match_nvt = pnv_xive_match_nvt;

> ?
>   
> > With or without the !!count change:
> 
> I will add the !! 
> 
> C. 
> 
> > 
> > Reviewed-by: Greg Kurz <address@hidden>
> > 
> >> 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));
> >>>>>
> >>>>
> >>>
> >>
> > 
>