Re: [PATCH v4] Drivers: hv: vmbus: Expose counters for interrupts and full conditions

[Sasha Levin]

On Mon, Feb 04, 2019 at 04:25:34PM +0000, Michael Kelley wrote:
> From: Kimberly Brown <kimbrownkd@xxxxxxxxx> Sent: Sunday, February 3, 2019 11:13 PM
> > Counter values for per-channel interrupts and ring buffer full
> > conditions are useful for investigating performance.
> >
> > Expose counters in sysfs for 2 types of guest to host interrupts:
> > 1) Interrupts caused by the channel's outbound ring buffer transitioning
> > from empty to not empty
> > 2) Interrupts caused by the channel's inbound ring buffer transitioning
> > from full to not full while a packet is waiting for enough buffer space to
> > become available
> >
> > Expose 2 counters in sysfs for the number of times that write operations
> > encountered a full outbound ring buffer:
> > 1) The total number of write operations that encountered a full
> > condition
> > 2) The number of write operations that were the first to encounter a
> > full condition
> >
> > Increment the outbound full condition counters in the
> > hv_ringbuffer_write() function because, for most drivers, a full
> > outbound ring buffer is detected in that function. Also increment the
> > outbound full condition counters in the set_channel_pending_send_size()
> > function. In the hv_sock driver, a full outbound ring buffer is detected
> > and set_channel_pending_send_size() is called before
> > hv_ringbuffer_write() is called.
> >
> > I tested this patch by confirming that the sysfs files were created and
> > observing the counter values. The values seemed to increase by a
> > reasonable amount when the Hyper-v related drivers were in use.
> >
> > Signed-off-by: Kimberly Brown <kimbrownkd@xxxxxxxxx>
> > ---
> Reviewed-by:  Michael Kelley <mikelley@xxxxxxxxxxxxx>

Queued for hyperv-next, thanks Kimberly!

--
Thanks,
Sasha