Strangely enough. Good point. Would have to be re-introduced soon, e.g. for the cuckoo distributor patch, though. But at least the "rte_cycles.h" is not needed any longer.
/Jan > -----Original Message----- > From: Ilya Maximets [mailto:[email protected]] > Sent: Friday, 12 January, 2018 13:57 > To: Jan Scheurich <[email protected]>; [email protected] > Subject: Re: [ovs-dev] [PATCH v8 2/2] dpif-netdev: Refactor cycle counting > > On 12.01.2018 15:52, Jan Scheurich wrote: > > Thanks for the info and hint. I will implement that in v9. > > > > I will also include "rte_config.h" in dpif-netdev.c. It didn't break ARM > > build so far because it happened to be included indirectly. > > Maybe it's better to remove include for rte_cycles.h from dpif-netdev.c > instead? > It looks like dpif-netdev does not use any dpdk functions anymore. > > > BR, Jan > > > >> -----Original Message----- > >> From: [email protected] > >> [mailto:[email protected]] On Behalf Of Ilya Maximets > >> Sent: Friday, 12 January, 2018 11:07 > >> To: Jan Scheurich <[email protected]>; [email protected] > >> Subject: Re: [ovs-dev] [PATCH v8 2/2] dpif-netdev: Refactor cycle counting > >> > >> Patch breaks ARMv8 build: > >> > >> In file included from lib/dpif-netdev-perf.c:20: > >> In file included from dpdk/build//include/rte_cycles.h:39: > >> In file included from dpdk/build//include/rte_cycles_32.h:49: > >> In file included from dpdk/build//include/generic/rte_cycles.h:46: > >> In file included from dpdk/build//include/rte_atomic.h:39: > >> dpdk/build//include/rte_atomic_32.h:37:4: error: Platform must be built > >> with CONFIG_RTE_FORCE_INTRINSICS > >> # error Platform must be built with CONFIG_RTE_FORCE_INTRINSICS > >> ^ > >> > >> The issue is that "rte_config.h" is not included. > >> You need following incremental for this patch: > >> ------------------------------------------------------------ > >> diff --git a/lib/dpif-netdev-perf.h b/lib/dpif-netdev-perf.h > >> index 297c184..f6e995b 100644 > >> --- a/lib/dpif-netdev-perf.h > >> +++ b/lib/dpif-netdev-perf.h > >> @@ -23,6 +23,11 @@ > >> #include <string.h> > >> #include <math.h> > >> > >> +#ifdef DPDK_NETDEV > >> +#include <rte_config.h> > >> +#include <rte_cycles.h> > >> +#endif > >> + > >> #include "openvswitch/vlog.h" > >> #include "ovs-atomic.h" > >> #include "timeval.h" > >> ------------------------------------------------------------ > >> > >> And following for the patch #1, because dpif-netdev-perf.c doesn't use > >> any DPDK functions: > >> ------------------------------------------------------------ > >> diff --git a/lib/dpif-netdev-perf.c b/lib/dpif-netdev-perf.c > >> index d609545..53fb41f 100644 > >> --- a/lib/dpif-netdev-perf.c > >> +++ b/lib/dpif-netdev-perf.c > >> @@ -16,10 +16,6 @@ > >> > >> #include <config.h> > >> > >> -#ifdef DPDK_NETDEV > >> -#include <rte_cycles.h> > >> -#endif > >> - > >> #include "openvswitch/dynamic-string.h" > >> #include "openvswitch/vlog.h" > >> #include "dpif-netdev-perf.h" > >> ------------------------------------------------------------ > >> > >> > >> Best regards, Ilya Maximets. > >> > >> On 11.01.2018 19:20, Jan Scheurich wrote: > >>> Simplify the historically grown TSC cycle counting in PMD threads. > >>> Cycles are currently counted for the following purposes: > >>> > >>> 1. Measure PMD ustilization > >>> > >>> PMD utilization is defined as ratio of cycles spent in busy iterations > >>> (at least one packet received or sent) over the total number of cycles. > >>> > >>> This is already done in pmd_perf_start_iteration() and > >>> pmd_perf_end_iteration() based on a TSC timestamp saved in current > >>> iteration at start_iteration() and the actual TSC at end_iteration(). > >>> No dependency on intermediate cycle accounting. > >>> > >>> 2. Measure the processing load per RX queue > >>> > >>> This comprises cycles spend on polling and processing packets received > >>> from the rx queue and the cycles spent on delayed sending of these packets > >>> to tx queues (with time-based batching). > >>> > >>> The previous scheme using cycles_count_start(), > >>> cycles_count_intermediate() > >>> and cycles-count_end() originally introduced to simplify cycle counting > >>> and saving calls to rte_get_tsc_cycles() was rather obscuring things. > >>> > >>> Replace by a nestable cycle_timer with with start and stop functions to > >>> embrace a code segment to be timed. The timed code may contain arbitrary > >>> nested cycle_timers. The duration of nested timers is excluded from the > >>> outer timer. > >>> > >>> The caller must ensure that each call to cycle_timer_start() is > >>> followed by a call to cycle_timer_end(). Failure to do so will lead to > >>> assertion failure or a memory leak. > >>> > >>> The new cycle_timer is used to measure the processing cycles per rx queue. > >>> This is not yet strictly necessary but will be made use of in a subsequent > >>> commit. > >>> > >>> All cycle count functions and data are relocated to module > >>> dpif-netdev-perf. > >>> > >>> Signed-off-by: Jan Scheurich <[email protected]> > >>> --- > >>> lib/dpif-netdev-perf.c | 1 + > >>> lib/dpif-netdev-perf.h | 99 +++++++++++++++++++++++++++++++++++++---- > >>> lib/dpif-netdev.c | 118 > >>> ++++++++++++++----------------------------------- > >>> 3 files changed, 125 insertions(+), 93 deletions(-) > >>> > >>> diff --git a/lib/dpif-netdev-perf.c b/lib/dpif-netdev-perf.c > >>> index bb4cf9d..d609545 100644 > >>> --- a/lib/dpif-netdev-perf.c > >>> +++ b/lib/dpif-netdev-perf.c > >>> @@ -31,6 +31,7 @@ void > >>> pmd_perf_stats_init(struct pmd_perf_stats *s) > >>> { > >>> memset(s, 0 , sizeof(*s)); > >>> + cycles_counter_update(s); > >>> } > >>> > >>> void > >>> diff --git a/lib/dpif-netdev-perf.h b/lib/dpif-netdev-perf.h > >>> index 53d60d3..297c184 100644 > >>> --- a/lib/dpif-netdev-perf.h > >>> +++ b/lib/dpif-netdev-perf.h > >>> @@ -59,10 +59,6 @@ enum pmd_stat_type { > >>> * recirculation. */ > >>> PMD_STAT_SENT_PKTS, /* Packets that have been sent. */ > >>> PMD_STAT_SENT_BATCHES, /* Number of batches sent. */ > >>> - PMD_CYCLES_POLL_IDLE, /* Cycles spent unsuccessful polling. */ > >>> - PMD_CYCLES_POLL_BUSY, /* Cycles spent successfully polling and > >>> - * processing polled packets. */ > >>> - PMD_CYCLES_OVERHEAD, /* Cycles spent for other tasks. */ > >>> PMD_CYCLES_ITER_IDLE, /* Cycles spent in idle iterations. */ > >>> PMD_CYCLES_ITER_BUSY, /* Cycles spent in busy iterations. */ > >>> PMD_N_STATS > >>> @@ -85,11 +81,95 @@ struct pmd_counters { > >>> > >>> struct pmd_perf_stats { > >>> /* Start of the current PMD iteration in TSC cycles.*/ > >>> + uint64_t start_it_tsc; > >>> + /* Latest TSC time stamp taken in PMD. */ > >>> uint64_t last_tsc; > >>> + /* If non-NULL, outermost cycle timer currently running in PMD. */ > >>> + struct cycle_timer *cur_timer; > >>> /* Set of PMD counters with their zero offsets. */ > >>> struct pmd_counters counters; > >>> }; > >>> > >>> +/* Support for accurate timing of PMD execution on TSC clock cycle level. > >>> + * These functions are intended to be invoked in the context of pmd > >>> threads. */ > >>> + > >>> +/* Read the TSC cycle register and cache it. Any function not requiring > >>> clock > >>> + * cycle accuracy should read the cached value using > >>> cycles_counter_get() to > >>> + * avoid the overhead of reading the TSC register. */ > >>> + > >>> +static inline uint64_t > >>> +cycles_counter_update(struct pmd_perf_stats *s) > >>> +{ > >>> +#ifdef DPDK_NETDEV > >>> + return s->last_tsc = rte_get_tsc_cycles(); > >>> +#else > >>> + return s->last_tsc = 0; > >>> +#endif > >>> +} > >>> + > >>> +static inline uint64_t > >>> +cycles_counter_get(struct pmd_perf_stats *s) > >>> +{ > >>> + return s->last_tsc; > >>> +} > >>> + > >>> +/* A nestable timer for measuring execution time in TSC cycles. > >>> + * > >>> + * Usage: > >>> + * struct cycle_timer timer; > >>> + * > >>> + * cycle_timer_start(pmd, &timer); > >>> + * <Timed execution> > >>> + * uint64_t cycles = cycle_timer_stop(pmd, &timer); > >>> + * > >>> + * The caller must guarantee that a call to cycle_timer_start() is always > >>> + * paired with a call to cycle_stimer_stop(). > >>> + * > >>> + * Is is possible to have nested cycles timers within the timed code. The > >>> + * execution time measured by the nested timers is excluded from the time > >>> + * measured by the embracing timer. > >>> + */ > >>> + > >>> +struct cycle_timer { > >>> + uint64_t start; > >>> + uint64_t suspended; > >>> + struct cycle_timer *interrupted; > >>> +}; > >>> + > >>> +static inline void > >>> +cycle_timer_start(struct pmd_perf_stats *s, > >>> + struct cycle_timer *timer) > >>> +{ > >>> + struct cycle_timer *cur_timer = s->cur_timer; > >>> + uint64_t now = cycles_counter_update(s); > >>> + > >>> + if (cur_timer) { > >>> + cur_timer->suspended = now; > >>> + } > >>> + timer->interrupted = cur_timer; > >>> + timer->start = now; > >>> + timer->suspended = 0; > >>> + s->cur_timer = timer; > >>> +} > >>> + > >>> +static inline uint64_t > >>> +cycle_timer_stop(struct pmd_perf_stats *s, > >>> + struct cycle_timer *timer) > >>> +{ > >>> + /* Assert that this is the current cycle timer. */ > >>> + ovs_assert(s->cur_timer == timer); > >>> + uint64_t now = cycles_counter_update(s); > >>> + struct cycle_timer *intr_timer = timer->interrupted; > >>> + > >>> + if (intr_timer) { > >>> + /* Adjust the start offset by the suspended cycles. */ > >>> + intr_timer->start += now - intr_timer->suspended; > >>> + } > >>> + /* Restore suspended timer, if any. */ > >>> + s->cur_timer = intr_timer; > >>> + return now - timer->start; > >>> +} > >>> + > >>> void pmd_perf_stats_init(struct pmd_perf_stats *s); > >>> void pmd_perf_stats_clear(struct pmd_perf_stats *s); > >>> void pmd_perf_read_counters(struct pmd_perf_stats *s, > >>> @@ -115,16 +195,17 @@ pmd_perf_update_counter(struct pmd_perf_stats *s, > >>> } > >>> > >>> static inline void > >>> -pmd_perf_start_iteration(struct pmd_perf_stats *s, uint64_t now_tsc) > >>> +pmd_perf_start_iteration(struct pmd_perf_stats *s) > >>> { > >>> - s->last_tsc = now_tsc; > >>> + /* We rely on here that the last_tsc was updated immediately prior > >>> + * at the end of the previous iteration, or before the first > >>> iteration. */ > >>> + s->start_it_tsc = s->last_tsc; > >>> } > >>> > >>> static inline void > >>> -pmd_perf_end_iteration(struct pmd_perf_stats *s, uint64_t now_tsc, > >>> - int rx_packets) > >>> +pmd_perf_end_iteration(struct pmd_perf_stats *s, int rx_packets) > >>> { > >>> - uint64_t cycles = now_tsc - s->last_tsc; > >>> + uint64_t cycles = cycles_counter_update(s) - s->start_it_tsc; > >>> > >>> if (rx_packets > 0) { > >>> pmd_perf_update_counter(s, PMD_CYCLES_ITER_BUSY, cycles); > >>> diff --git a/lib/dpif-netdev.c b/lib/dpif-netdev.c > >>> index 82d29bb..dc26026 100644 > >>> --- a/lib/dpif-netdev.c > >>> +++ b/lib/dpif-netdev.c > >>> @@ -509,8 +509,6 @@ struct tx_port { > >>> struct dp_netdev_pmd_thread_ctx { > >>> /* Latest measured time. See 'pmd_thread_ctx_time_update()'. */ > >>> long long now; > >>> - /* Used to count cycles. See 'cycles_count_end()' */ > >>> - unsigned long long last_cycles; > >>> }; > >>> > >>> /* PMD: Poll modes drivers. PMD accesses devices via polling to > >>> eliminate > >>> @@ -3111,64 +3109,20 @@ dp_netdev_actions_free(struct dp_netdev_actions > >>> *actions) > >>> free(actions); > >>> } > >>> > > > >>> -static inline unsigned long long > >>> -cycles_counter(void) > >>> -{ > >>> -#ifdef DPDK_NETDEV > >>> - return rte_get_tsc_cycles(); > >>> -#else > >>> - return 0; > >>> -#endif > >>> -} > >>> - > >>> -/* Fake mutex to make sure that the calls to cycles_count_* are balanced > >>> */ > >>> -extern struct ovs_mutex cycles_counter_fake_mutex; > >>> - > >>> -/* Start counting cycles. Must be followed by 'cycles_count_end()' */ > >>> -static inline void > >>> -cycles_count_start(struct dp_netdev_pmd_thread *pmd) > >>> - OVS_ACQUIRES(&cycles_counter_fake_mutex) > >>> - OVS_NO_THREAD_SAFETY_ANALYSIS > >>> -{ > >>> - pmd->ctx.last_cycles = cycles_counter(); > >>> -} > >>> - > >>> -/* Stop counting cycles and add them to the counter 'type' */ > >>> -static inline void > >>> -cycles_count_end(struct dp_netdev_pmd_thread *pmd, > >>> - enum pmd_stat_type type) > >>> - OVS_RELEASES(&cycles_counter_fake_mutex) > >>> - OVS_NO_THREAD_SAFETY_ANALYSIS > >>> -{ > >>> - unsigned long long interval = cycles_counter() - > >>> pmd->ctx.last_cycles; > >>> - > >>> - pmd_perf_update_counter(&pmd->perf_stats, type, interval); > >>> -} > >>> - > >>> -/* Calculate the intermediate cycle result and add to the counter 'type' > >>> */ > >>> -static inline void > >>> -cycles_count_intermediate(struct dp_netdev_pmd_thread *pmd, > >>> - struct dp_netdev_rxq *rxq, > >>> - enum pmd_stat_type type) > >>> - OVS_NO_THREAD_SAFETY_ANALYSIS > >>> +static void > >>> +dp_netdev_rxq_set_cycles(struct dp_netdev_rxq *rx, > >>> + enum rxq_cycles_counter_type type, > >>> + unsigned long long cycles) > >>> { > >>> - unsigned long long new_cycles = cycles_counter(); > >>> - unsigned long long interval = new_cycles - pmd->ctx.last_cycles; > >>> - pmd->ctx.last_cycles = new_cycles; > >>> - > >>> - pmd_perf_update_counter(&pmd->perf_stats, type, interval); > >>> - if (rxq && (type == PMD_CYCLES_POLL_BUSY)) { > >>> - /* Add to the amount of current processing cycles. */ > >>> - non_atomic_ullong_add(&rxq->cycles[RXQ_CYCLES_PROC_CURR], > >>> interval); > >>> - } > >>> + atomic_store_relaxed(&rx->cycles[type], cycles); > >>> } > >>> > >>> static void > >>> -dp_netdev_rxq_set_cycles(struct dp_netdev_rxq *rx, > >>> +dp_netdev_rxq_add_cycles(struct dp_netdev_rxq *rx, > >>> enum rxq_cycles_counter_type type, > >>> unsigned long long cycles) > >>> { > >>> - atomic_store_relaxed(&rx->cycles[type], cycles); > >>> + non_atomic_ullong_add(&rx->cycles[type], cycles); > >>> } > >>> > >>> static uint64_t > >>> @@ -3234,27 +3188,40 @@ dp_netdev_pmd_flush_output_packets(struct > >>> dp_netdev_pmd_thread *pmd) > >>> > >>> static int > >>> dp_netdev_process_rxq_port(struct dp_netdev_pmd_thread *pmd, > >>> - struct netdev_rxq *rx, > >>> + struct dp_netdev_rxq *rxq, > >>> odp_port_t port_no) > >>> { > >>> struct dp_packet_batch batch; > >>> + struct cycle_timer timer; > >>> int error; > >>> int batch_cnt = 0; > >>> > >>> + /* Measure duration for polling and processing rx burst. */ > >>> + cycle_timer_start(&pmd->perf_stats, &timer); > >>> dp_packet_batch_init(&batch); > >>> - error = netdev_rxq_recv(rx, &batch); > >>> + error = netdev_rxq_recv(rxq->rx, &batch); > >>> if (!error) { > >>> + /* At least one packet received. */ > >>> *recirc_depth_get() = 0; > >>> pmd_thread_ctx_time_update(pmd); > >>> > >>> batch_cnt = batch.count; > >>> dp_netdev_input(pmd, &batch, port_no); > >>> dp_netdev_pmd_flush_output_packets(pmd); > >>> - } 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)); > >>> + /* Assign processing cycles to rx queue. */ > >>> + uint64_t cycles = cycle_timer_stop(&pmd->perf_stats, &timer); > >>> + dp_netdev_rxq_add_cycles(rxq, RXQ_CYCLES_PROC_CURR, cycles); > >>> + > >>> + } else { > >>> + /* Discard cycles. */ > >>> + cycle_timer_stop(&pmd->perf_stats, &timer); > >>> + 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(rxq->rx), ovs_strerror(error)); > >>> + } > >>> } > >>> > >>> return batch_cnt; > >>> @@ -3880,30 +3847,22 @@ 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++) { > >>> - process_packets = > >>> - dp_netdev_process_rxq_port(non_pmd, > >>> - port->rxqs[i].rx, > >>> - port->port_no); > >>> - cycles_count_intermediate(non_pmd, NULL, > >>> - process_packets > >>> - ? PMD_CYCLES_POLL_BUSY > >>> - : PMD_CYCLES_POLL_IDLE); > >>> + dp_netdev_process_rxq_port(non_pmd, > >>> + &port->rxqs[i], > >>> + port->port_no); > >>> } > >>> } > >>> } > >>> - cycles_count_end(non_pmd, PMD_CYCLES_POLL_IDLE); > >>> pmd_thread_ctx_time_update(non_pmd); > >>> dpif_netdev_xps_revalidate_pmd(non_pmd, false); > >>> ovs_mutex_unlock(&dp->non_pmd_mutex); > >>> @@ -4082,18 +4041,14 @@ reload: > >>> lc = UINT_MAX; > >>> } > >>> > >>> - cycles_count_start(pmd); > >>> + cycles_counter_update(s); > >>> for (;;) { > >>> uint64_t iter_packets = 0; > >>> - pmd_perf_start_iteration(s, pmd->ctx.last_cycles); > >>> + pmd_perf_start_iteration(s); > >>> for (i = 0; i < poll_cnt; i++) { > >>> process_packets = > >>> - dp_netdev_process_rxq_port(pmd, poll_list[i].rxq->rx, > >>> + dp_netdev_process_rxq_port(pmd, poll_list[i].rxq, > >>> poll_list[i].port_no); > >>> - cycles_count_intermediate(pmd, poll_list[i].rxq, > >>> - process_packets > >>> - ? PMD_CYCLES_POLL_BUSY > >>> - : PMD_CYCLES_POLL_IDLE); > >>> iter_packets += process_packets; > >>> } > >>> > >>> @@ -4115,13 +4070,10 @@ reload: > >>> if (reload) { > >>> break; > >>> } > >>> - cycles_count_intermediate(pmd, NULL, PMD_CYCLES_OVERHEAD); > >>> } > >>> - pmd_perf_end_iteration(s, pmd->ctx.last_cycles, iter_packets); > >>> + pmd_perf_end_iteration(s, iter_packets); > >>> } > >>> > >>> - cycles_count_end(pmd, PMD_CYCLES_OVERHEAD); > >>> - > >>> 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 > >>> @@ -5066,9 +5018,7 @@ handle_packet_upcall(struct dp_netdev_pmd_thread > >>> *pmd, > >>> ovs_mutex_unlock(&pmd->flow_mutex); > >>> emc_probabilistic_insert(pmd, key, netdev_flow); > >>> } > >>> - /* Only error ENOSPC can reach here. We process the packet but do not > >>> - * install a datapath flow. Treat as successful. */ > >>> - return 0; > >>> + return error; > >>> } > >>> > >>> static inline void > >>> > >> _______________________________________________ > >> dev mailing list > >> [email protected] > >> https://mail.openvswitch.org/mailman/listinfo/ovs-dev > > > > > > _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
