Instead of counting all polling cycles as processing cycles, only count the cycles where packets were received from the polling.
Signed-off-by: Georg Schmuecking <georg.schmueck...@ericsson.com> Signed-off-by: Ciara Loftus <ciara.lof...@intel.com> Co-authored-by: Georg Schmuecking <georg.schmueck...@ericsson.com> Acked-by: Kevin Traynor <ktray...@redhat.com> --- v3: - Updated acks & co-author tags - Removed unnecessary PMD_CYCLES_POLLING counter type - Explain terms 'idle' and 'processing' cycles in vswitchd/ovs-vswitchd.8.in v2: - Rebase lib/dpif-netdev.c | 57 ++++++++++++++++++++++++++++++++++------------ vswitchd/ovs-vswitchd.8.in | 5 +++- 2 files changed, 47 insertions(+), 15 deletions(-) diff --git a/lib/dpif-netdev.c b/lib/dpif-netdev.c index 30907b7..6bf6809 100644 --- a/lib/dpif-netdev.c +++ b/lib/dpif-netdev.c @@ -279,8 +279,9 @@ enum dp_stat_type { }; enum pmd_cycles_counter_type { - PMD_CYCLES_POLLING, /* Cycles spent polling NICs. */ - PMD_CYCLES_PROCESSING, /* Cycles spent processing packets */ + PMD_CYCLES_IDLE, /* Cycles spent idle or unsuccessful polling */ + PMD_CYCLES_PROCESSING, /* Cycles spent successfully polling and + * processing polled packets */ PMD_N_CYCLES }; @@ -755,10 +756,10 @@ pmd_info_show_stats(struct ds *reply, } ds_put_format(reply, - "\tpolling cycles:%"PRIu64" (%.02f%%)\n" + "\tidle cycles:%"PRIu64" (%.02f%%)\n" "\tprocessing cycles:%"PRIu64" (%.02f%%)\n", - cycles[PMD_CYCLES_POLLING], - cycles[PMD_CYCLES_POLLING] / (double)total_cycles * 100, + cycles[PMD_CYCLES_IDLE], + cycles[PMD_CYCLES_IDLE] / (double)total_cycles * 100, cycles[PMD_CYCLES_PROCESSING], cycles[PMD_CYCLES_PROCESSING] / (double)total_cycles * 100); @@ -2953,30 +2954,43 @@ cycles_count_end(struct dp_netdev_pmd_thread *pmd, non_atomic_ullong_add(&pmd->cycles.n[type], interval); } -static void +/* Calculate the intermediate cycle result and add to the counter 'type' */ +static inline void +cycles_count_intermediate(struct dp_netdev_pmd_thread *pmd, + enum pmd_cycles_counter_type type) + OVS_NO_THREAD_SAFETY_ANALYSIS +{ + unsigned long long new_cycles = cycles_counter(); + unsigned long long interval = new_cycles - pmd->last_cycles; + pmd->last_cycles = new_cycles; + + non_atomic_ullong_add(&pmd->cycles.n[type], interval); +} + +static int dp_netdev_process_rxq_port(struct dp_netdev_pmd_thread *pmd, struct netdev_rxq *rx, odp_port_t port_no) { struct dp_packet_batch batch; int error; + int batch_cnt = 0; dp_packet_batch_init(&batch); - cycles_count_start(pmd); error = netdev_rxq_recv(rx, &batch); - cycles_count_end(pmd, PMD_CYCLES_POLLING); if (!error) { *recirc_depth_get() = 0; - cycles_count_start(pmd); + batch_cnt = batch.count; dp_netdev_input(pmd, &batch, port_no); - cycles_count_end(pmd, PMD_CYCLES_PROCESSING); } else if (error != EAGAIN && error != EOPNOTSUPP) { static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5); VLOG_ERR_RL(&rl, "error receiving data from %s: %s", netdev_rxq_get_name(rx), ovs_strerror(error)); } + + return batch_cnt; } static struct tx_port * @@ -3438,21 +3452,27 @@ dpif_netdev_run(struct dpif *dpif) struct dp_netdev *dp = get_dp_netdev(dpif); struct dp_netdev_pmd_thread *non_pmd; uint64_t new_tnl_seq; + int process_packets = 0; ovs_mutex_lock(&dp->port_mutex); non_pmd = dp_netdev_get_pmd(dp, NON_PMD_CORE_ID); if (non_pmd) { ovs_mutex_lock(&dp->non_pmd_mutex); + cycles_count_start(non_pmd); HMAP_FOR_EACH (port, node, &dp->ports) { if (!netdev_is_pmd(port->netdev)) { int i; for (i = 0; i < port->n_rxq; i++) { - dp_netdev_process_rxq_port(non_pmd, port->rxqs[i].rx, - port->port_no); + process_packets += + dp_netdev_process_rxq_port(non_pmd, + port->rxqs[i].rx, + port->port_no); } } } + cycles_count_end(non_pmd, process_packets ? PMD_CYCLES_PROCESSING + : PMD_CYCLES_IDLE); dpif_netdev_xps_revalidate_pmd(non_pmd, time_msec(), false); ovs_mutex_unlock(&dp->non_pmd_mutex); @@ -3577,6 +3597,7 @@ pmd_thread_main(void *f_) bool exiting; int poll_cnt; int i; + int process_packets = 0; poll_list = NULL; @@ -3603,10 +3624,12 @@ reload: lc = UINT_MAX; } + cycles_count_start(pmd); for (;;) { for (i = 0; i < poll_cnt; i++) { - dp_netdev_process_rxq_port(pmd, poll_list[i].rx, - poll_list[i].port_no); + process_packets += + dp_netdev_process_rxq_port(pmd, poll_list[i].rx, + poll_list[i].port_no); } if (lc++ > 1024) { @@ -3625,8 +3648,14 @@ reload: break; } } + cycles_count_intermediate(pmd, process_packets ? PMD_CYCLES_PROCESSING + : PMD_CYCLES_IDLE); + process_packets = 0; } + cycles_count_end(pmd, process_packets ? PMD_CYCLES_PROCESSING + : PMD_CYCLES_IDLE); + poll_cnt = pmd_load_queues_and_ports(pmd, &poll_list); exiting = latch_is_set(&pmd->exit_latch); /* Signal here to make sure the pmd finishes diff --git a/vswitchd/ovs-vswitchd.8.in b/vswitchd/ovs-vswitchd.8.in index fc19f3b..2e6e684 100644 --- a/vswitchd/ovs-vswitchd.8.in +++ b/vswitchd/ovs-vswitchd.8.in @@ -253,7 +253,10 @@ The sum of ``emc hits'', ``masked hits'' and ``miss'' is the number of packets received by the datapath. Cycles are counted using the TSC or similar facilities (when available on the platform). To reset these counters use \fBdpif-netdev/pmd-stats-clear\fR. The duration of one cycle depends on the -measuring infrastructure. +measuring infrastructure. ``idle cycles'' refers to cycles spent polling +devices but not receiving any packets. ``processing cycles'' refers to cycles +spent polling devices and sucessfully receiving packets, plus the cycles +spent processing said packets. .IP "\fBdpif-netdev/pmd-stats-clear\fR [\fIdp\fR]" Resets to zero the per pmd thread performance numbers shown by the \fBdpif-netdev/pmd-stats-show\fR command. It will NOT reset datapath or -- 2.4.11 _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev