[intel] Exclude time spent in hypervisor from profiling

When profiling, exclude any time spent inside the hypervisor
responding to our MMIO accesses.  This substantially reduces the
variance accumulated on many other profilers.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

diff --git a/src/drivers/net/intel.c b/src/drivers/net/intel.c
index 6684bdbd9c4896aa0c290287580ea37a6c6c8ba7..771a4c82488644a4370499f6c9b08f932cb11611 100644 (file)
--- a/src/drivers/net/intel.c
+++ b/src/drivers/net/intel.c
@@ -496,6 +496,7 @@ void intel_refill_rx ( struct intel_nic *intel ) {
                profile_start ( &intel_vm_refill_profiler );
                writel ( rx_tail, intel->regs + intel->rx.reg + INTEL_xDT );
                profile_stop ( &intel_vm_refill_profiler );
+               profile_exclude ( &intel_vm_refill_profiler );
        }
 }
 
@@ -634,6 +635,7 @@ int intel_transmit ( struct net_device *netdev, struct io_buffer *iobuf ) {
        profile_start ( &intel_vm_tx_profiler );
        writel ( tx_tail, intel->regs + intel->tx.reg + INTEL_xDT );
        profile_stop ( &intel_vm_tx_profiler );
+       profile_exclude ( &intel_vm_tx_profiler );
 
        DBGC2 ( intel, "INTEL %p TX %d is [%llx,%llx)\n", intel, tx_idx,
                ( ( unsigned long long ) address ),
@@ -728,6 +730,7 @@ static void intel_poll ( struct net_device *netdev ) {
        profile_start ( &intel_vm_poll_profiler );
        icr = readl ( intel->regs + INTEL_ICR );
        profile_stop ( &intel_vm_poll_profiler );
+       profile_exclude ( &intel_vm_poll_profiler );
        if ( ! icr )
                return;