On 12/07/2019 03:15, David Gibson wrote: > On Wed, Jul 03, 2019 at 07:54:57AM +0200, Cédric Le Goater wrote: >> On 03/07/2019 04:07, David Gibson wrote: >>> On Sun, Jun 30, 2019 at 10:45:59PM +0200, Cédric Le Goater wrote: >>>> This is to perform lookups in the NVT table when a vCPU is dispatched >>>> and possibly resend interrupts. >>> >>> I'm slightly confused by this one. Aren't there multiple router >>> objects, each of which can deliver to any thread? In which case what >>> router object is associated with a specific TCTX? >> >> when a vCPU is dispatched on a HW thread, the hypervisor does a store >> on the CAM line to store the VP id. At that time, it checks the IPB in >> the associated NVT structure and notifies the thread if an interrupt is >> pending. >> >> We need to do a NVT lookup, just like the presenter in HW, hence the >> router pointer. You should look at the following patch which clarifies >> the resend sequence. > > Hm, ok. > >>>> Future XIVE chip will use a different class for the model of the >>>> interrupt controller. So use an 'Object *' instead of a 'XiveRouter *'. >>> >>> This seems odd to me, shouldn't it be an interface pointer or >>> something in that case? >> >> I have duplicated most of the XIVE models for P10 because the internal >> structures have changed. I managed to keep the XiveSource and XiveTCTX >> but we now have a Xive10Router, this is the reason why. > > Right, but XiveRouter and Xive10Router must have something in common > if they can both be used here. Usually that's expressed as a shared > QOM interface - in which case you can use a pointer to the interface, > rathe than using Object * which kind of implies *anything* can go > here.
Yeah. I also think it would be better to have a common base object but the class don't have much in common. Here is what I have for now : P9: typedef struct XiveRouterClass { SysBusDeviceClass parent; /* XIVE table accessors */ int (*get_eas)(XiveRouter *xrtr, uint8_t eas_blk, uint32_t eas_idx, XiveEAS *eas); int (*get_end)(XiveRouter *xrtr, uint8_t end_blk, uint32_t end_idx, XiveEND *end); int (*write_end)(XiveRouter *xrtr, uint8_t end_blk, uint32_t end_idx, XiveEND *end, uint8_t word_number); int (*get_nvt)(XiveRouter *xrtr, uint8_t nvt_blk, uint32_t nvt_idx, XiveNVT *nvt); int (*write_nvt)(XiveRouter *xrtr, uint8_t nvt_blk, uint32_t nvt_idx, XiveNVT *nvt, uint8_t word_number); XiveTCTX *(*get_tctx)(XiveRouter *xrtr, CPUState *cs); uint8_t (*get_block_id)(XiveRouter *xrtr); } XiveRouterClass; and P10: typedef struct Xive10RouterClass { SysBusDeviceClass parent; /* XIVE table accessors */ int (*get_eas)(Xive10Router *xrtr, uint8_t eas_blk, uint32_t eas_idx, Xive10EAS *eas); int (*get_end)(Xive10Router *xrtr, uint8_t end_blk, uint32_t end_idx, Xive10END *end); int (*write_end)(Xive10Router *xrtr, uint8_t end_blk, uint32_t end_idx, Xive10END *end, uint8_t word_number); int (*get_nvp)(Xive10Router *xrtr, uint8_t nvt_blk, uint32_t nvt_idx, Xive10NVP *nvt); int (*write_nvp)(Xive10Router *xrtr, uint8_t nvt_blk, uint32_t nvt_idx, Xive10NVP *nvt, uint8_t word_number); XiveTCTX *(*get_tctx)(Xive10Router *xrtr, CPUState *cs); uint8_t (*get_block_id)(XiveRouter *xrtr); uint32_t (*get_config)(Xive10Router *xrtr); } Xive10RouterClass; Only get_tctx() is common. The XIVE structures (END, NV*) used by the routing algo have changed a lot. Even the presenter has changed, because all the CAM lines have a slightly different format. C.