Jonathan Cameron wrote:
> On Tue, 27 Aug 2024 09:40:05 -0700
> nifan....@gmail.com wrote:
>
> > From: Fan Ni <fan...@samsung.com>
> >
> > When inserting multiple dynamic capacity event records grouped via More
> > flag,
> > we should only trigger interrupt after the last record is inserted into the
> > event log. Achieving the goal by letting cxl_event_insert return true only
> > for the insertion of the last dynamic capacity event record in the sequence.
>
> I'm not sure this one is accurate. We might well have a slow
> system provisioning capacity one extent at time (and interrupting).
>
> The event buffer might also not be large enough to hold all records so
> the device might 'wait' before figuring out the next extent for there
> to be somewhere to put the record.
>
> Overall I think we can interrupt on each one and it should 'work'
> as should interrupt only once there are lots of them or
> every (n).
Indeed I think it should work. But you won't see any extents as they will
be pending in the memdev.
Did this fail in some way? I'm sorry I did not try and use qemu to test
the more bit. Rather I used cxl_test for that.
Ira
>
> Interrupt only fires on a 0 to >= 1 transition anyway, not
> on repeats after that unless the log has been cleared.
> It's up to OS to keep clearing records until it at least
> momentarily hits 0 if it wants to get any more interrupts.
>
> Jonathan
>
>
> >
> > Signed-off-by: Fan Ni <fan...@samsung.com>
> > ---
> > hw/cxl/cxl-events.c | 8 ++++++++
> > include/hw/cxl/cxl_events.h | 1 +
> > 2 files changed, 9 insertions(+)
> >
> > diff --git a/hw/cxl/cxl-events.c b/hw/cxl/cxl-events.c
> > index 12dee2e467..90536c0e68 100644
> > --- a/hw/cxl/cxl-events.c
> > +++ b/hw/cxl/cxl-events.c
> > @@ -135,6 +135,14 @@ bool cxl_event_insert(CXLDeviceState *cxlds,
> > CXLEventLogType log_type,
> > QSIMPLEQ_INSERT_TAIL(&log->events, entry, node);
> > cxl_event_set_status(cxlds, log_type, true);
> >
> > + /*
> > + * For dynamic capacity event records grouped via More flag,
> > + * Only raise interrupt after inserting the last record in the log.
> > + */
> > + if (log_type == CXL_EVENT_TYPE_DYNAMIC_CAP) {
> > + CXLEventDynamicCapacity *dCap = (CXLEventDynamicCapacity *)event;
> > + return (dCap->flags & MORE_FLAG) ? false : true;
> > + }
> > /* Count went from 0 to 1 */
> > return cxl_event_count(log) == 1;
>
> If there are multiple this will fail I think as cxl_event_count(log) will go
> from 0
> to X not 1.
>
> > }
> > diff --git a/include/hw/cxl/cxl_events.h b/include/hw/cxl/cxl_events.h
> > index 38cadaa0f3..b0e5cc89c0 100644
> > --- a/include/hw/cxl/cxl_events.h
> > +++ b/include/hw/cxl/cxl_events.h
> > @@ -170,6 +170,7 @@ typedef struct CXLEventMemoryModule {
> > * CXL r3.1 section Table 8-50: Dynamic Capacity Event Record
> > * All fields little endian.
> > */
> > +#define MORE_FLAG BIT_MASK(0)
> > typedef struct CXLEventDynamicCapacity {
> > CXLEventRecordHdr hdr;
> > uint8_t type;
>
