diff options
| author | Kevin Traynor <ktraynor@redhat.com> | 2017-11-23 19:41:55 +0000 |
|---|---|---|
| committer | Ian Stokes <ian.stokes@intel.com> | 2017-12-08 21:42:54 +0000 |
| commit | a130f1a89bd8ec1176ac8d35a98c284a5e3f5691 (patch) | |
| tree | e08562c4525420c765fc65bc15104eb66eb9c57a /lib | |
| parent | 255b7bda98974c9732c435c3d500d50e20bd728e (diff) | |
| download | openvswitch-a130f1a89bd8ec1176ac8d35a98c284a5e3f5691.tar.gz | |
dpif-netdev: Add port/queue tiebreaker to rxq_cycle_sort.
rxq_cycle_sort is used to compare rx queues by their measured number
of cycles. In the event that they are equal, 0 could be returned.
However, it is observed that returning 0 results in a different sort
order on Windows/Linux. This is ok in practice but it causes a unit
test failure for
"1007: PMD - pmd-cpu-mask/distribution of rx queues" when running
on different OS's.
In order to have a consistent sort result across multiple OS's,
introduce a tiebreaker of port/queue.
Fixes: 655856ef39b9 ("dpif-netdev: Change rxq_scheduling to use rxq processing cycles.")
Reported-by: Alin Gabriel Serdean <aserdean@ovn.org>
Tested-by: Alin Gabriel Serdean <aserdean@ovn.org>
Co-authored-by: Ilya Maximets <i.maximets@samsung.com>
Signed-off-by: Ilya Maximets <i.maximets@samsung.com>
Signed-off-by: Kevin Traynor <ktraynor@redhat.com>
Signed-off-by: Ian Stokes <ian.stokes@intel.com>
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/dpif-netdev.c | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/lib/dpif-netdev.c b/lib/dpif-netdev.c index b1ef9a6a5..b5a1bfec3 100644 --- a/lib/dpif-netdev.c +++ b/lib/dpif-netdev.c @@ -3463,10 +3463,19 @@ rxq_cycle_sort(const void *a, const void *b) dp_netdev_rxq_set_cycles(qa, RXQ_CYCLES_PROC_HIST, total_qa); dp_netdev_rxq_set_cycles(qb, RXQ_CYCLES_PROC_HIST, total_qb); - if (total_qa >= total_qb) { - return -1; + if (total_qa != total_qb) { + return (total_qa < total_qb) ? 1 : -1; + } else { + /* Cycles are the same so tiebreak on port/queue id. + * Tiebreaking (as opposed to return 0) ensures consistent + * sort results across multiple OS's. */ + if (qa->port->port_no != qb->port->port_no) { + return (qa->port->port_no > qb->port->port_no) ? 1 : -1; + } else { + return netdev_rxq_get_queue_id(qa->rx) + - netdev_rxq_get_queue_id(qb->rx); + } } - return 1; } /* Assign pmds to queues. If 'pinned' is true, assign pmds to pinned |