VNFs/DPPD-PROX/handle_irq.c

   1 /*
   2 // Copyright (c) 2010-2017 Intel Corporation
   3 //
   4 // Licensed under the Apache License, Version 2.0 (the "License");
   5 // you may not use this file except in compliance with the License.
   6 // You may obtain a copy of the License at
   7 //
   8 //     http://www.apache.org/licenses/LICENSE-2.0
   9 //
  10 // Unless required by applicable law or agreed to in writing, software
  11 // distributed under the License is distributed on an "AS IS" BASIS,
  12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13 // See the License for the specific language governing permissions and
  14 // limitations under the License.
  15 */
  16
  17 #include <rte_cycles.h>
  18
  19 #include "lconf.h"
  20 #include "task_base.h"
  21 #include "task_init.h"
  22 #include "handle_irq.h"
  23 #include "stats_irq.h"
  24 #include "log.h"
  25 #include "unistd.h"
  26 #include "input.h"
  27
  28 #define MAX_INTERRUPT_LENGTH    500000  /* Maximum length of an interrupt is (1 / MAX_INTERRUPT_LENGTH) seconds */
  29 uint64_t irq_bucket_maxtime_micro[] = {1,5,10,50,100,500,1000,5000,10000,50000,100000,500000,UINT64_MAX};
  30 /*
  31  *      This module is not handling any packets.
  32  *      It loops on rdtsc() and checks whether it has been interrupted
  33  *               for more than (1 / MAX_INTERRUPT_LENGTH) sec.
  34  *      This is a debugging only task, useful to check if the system h
  35  *              as been properly configured.
  36 */
  37
  38 static void update_irq_stats(struct task_irq *task, uint64_t irq)
  39 {
  40         if (irq > task->stats.max_irq)
  41                 task->stats.max_irq = irq;
  42         for (uint i = 0; i < IRQ_BUCKETS_COUNT; ++i) {
  43                 if (irq < irq_bucket_maxtime_cycles[i]) {
  44                         task->stats.irq[i]++;
  45                         break;
  46                 }
  47         }
  48 }
  49
  50 void task_irq_show_stats(struct task_irq *task_irq, struct input *input)
  51 {
  52         struct irq_bucket *bucket = &task_irq->buffer[!task_irq->task_use_lt];
  53         if (input->reply) {
  54                 char buf[8192] = {0};
  55                 if (bucket->index == 0) {
  56                         sprintf(buf, "\n");
  57                         input->reply(input, buf, strlen(buf));
  58                         buf[0] = 0;
  59                 }
  60                 for (uint64_t i = 0; i < bucket->index; i++) {
  61                         sprintf(buf + strlen(buf), "%d; %"PRIu64"""; %ld; %ld; %ld; %ld ;",
  62                                 task_irq->lcore_id,
  63                                 i,
  64                                 bucket->info[i].lat,
  65                                 bucket->info[i].lat * 1000000 / rte_get_tsc_hz(),
  66                                 bucket->info[i].tsc - task_irq->start_tsc,
  67                                 (bucket->info[i].tsc - task_irq->start_tsc) * 1000 / rte_get_tsc_hz());
  68                         sprintf(buf+strlen(buf), "\n");
  69                         input->reply(input, buf, strlen(buf));
  70                         buf[0] = 0;
  71                 }
  72         } else {
  73                 for (uint64_t i = 0; i < bucket->index; i++)
  74                         if (bucket->info[i].lat)
  75                                 plog_info("[%d]; Interrupt %"PRIu64": %ld cycles (%ld micro-sec) at %ld cycles (%ld msec)\n",
  76                                           task_irq->lcore_id,
  77                                           i,
  78                                           bucket->info[i].lat,
  79                                           bucket->info[i].lat * 1000000 / rte_get_tsc_hz(),
  80                                           bucket->info[i].tsc - task_irq->start_tsc,
  81                                           (bucket->info[i].tsc - task_irq->start_tsc) * 1000 / rte_get_tsc_hz());
  82         }
  83         task_irq->stats_use_lt = !task_irq->task_use_lt;
  84         bucket->index = 0;
  85 }
  86
  87 static void irq_stop(struct task_base *tbase)
  88 {
  89         struct task_irq *task = (struct task_irq *)tbase;
  90         uint32_t i;
  91         uint32_t lcore_id = rte_lcore_id();
  92         uint64_t lat, max_lat = 0, tot_lat = 0;
  93         int bucket_id;
  94         int n_lat = 0;
  95
  96         if (task->irq_debug) {
  97                 plog_info("Stopping core %u\n", lcore_id);
  98                 sleep(2);       // Make sure all cores are stopped before starting to write
  99                 plog_info("Core ID; Interrupt (nanosec); Time (msec)\n");
 100                 for (int j = 0; j < 2; j++) {
 101                         // Start dumping the oldest bucket first
 102                         if (task->buffer[0].info[0].tsc < task->buffer[1].info[0].tsc)
 103                                 bucket_id = j;
 104                         else
 105                                 bucket_id = !j;
 106                         struct irq_bucket *bucket = &task->buffer[bucket_id];
 107                         for (i=0; i< bucket->index;i++) {
 108                                 if (bucket->info[i].lat != 0) {
 109                                         lat = bucket->info[i].lat * 1000000000 / rte_get_tsc_hz();
 110                                         if (max_lat < lat)
 111                                                 max_lat = lat;
 112                                         n_lat++;
 113                                         tot_lat += lat;
 114                                         plog_info("%d; %ld; %ld\n", lcore_id, lat,
 115                                                 (bucket->info[i].tsc - task->start_tsc) * 1000 / rte_get_tsc_hz());
 116                                 }
 117                         }
 118                 }
 119                 if (n_lat)
 120                         tot_lat = tot_lat / n_lat;
 121                 plog_info("Core %u stopped. max lat is %ld and average is %ld\n", lcore_id, max_lat, tot_lat);
 122         }
 123 }
 124
 125 static inline int handle_irq_bulk(struct task_base *tbase, struct rte_mbuf **mbufs, uint16_t n_pkts)
 126 {
 127         struct task_irq *task = (struct task_irq *)tbase;
 128         uint64_t tsc1;
 129         uint64_t index;
 130
 131         if (task->stats_use_lt != task->task_use_lt)
 132                 task->task_use_lt = task->stats_use_lt;
 133         struct irq_bucket *bucket = &task->buffer[task->task_use_lt];
 134
 135         tsc1 = rte_rdtsc();
 136         if ((tsc1 > task->first_tsc) && (task->tsc != 0)) {
 137                 update_irq_stats(task, tsc1 - task->tsc);
 138                 if (((tsc1 - task->tsc) > task->max_irq) && (bucket->index < MAX_INDEX)) {
 139                         bucket->info[bucket->index].tsc = tsc1;
 140                         bucket->info[bucket->index++].lat = tsc1 - task->tsc;
 141                 }
 142         }
 143         task->tsc = tsc1;
 144         return 0;
 145 }
 146
 147 static void init_task_irq(struct task_base *tbase,
 148                           __attribute__((unused)) struct task_args *targ)
 149 {
 150         struct task_irq *task = (struct task_irq *)tbase;
 151         task->start_tsc = rte_rdtsc();
 152         task->first_tsc = task->start_tsc + 2 * rte_get_tsc_hz();
 153         task->lcore_id = targ->lconf->id;
 154         task->irq_debug = targ->irq_debug;
 155         // max_irq expressed in cycles
 156         task->max_irq = rte_get_tsc_hz() / MAX_INTERRUPT_LENGTH;
 157         plog_info("\tusing irq mode with max irq set to %ld cycles\n", task->max_irq);
 158
 159         for (uint bucket_id = 0; bucket_id < IRQ_BUCKETS_COUNT - 1; bucket_id++)
 160                 irq_bucket_maxtime_cycles[bucket_id] = rte_get_tsc_hz() * irq_bucket_maxtime_micro[bucket_id] / 1000000;
 161         irq_bucket_maxtime_cycles[IRQ_BUCKETS_COUNT - 1] = UINT64_MAX;
 162 }
 163
 164 static struct task_init task_init_irq = {
 165         .mode_str = "irq",
 166         .init = init_task_irq,
 167         .handle = handle_irq_bulk,
 168         .stop = irq_stop,
 169         .flag_features = TASK_FEATURE_NO_RX,
 170         .size = sizeof(struct task_irq)
 171 };
 172
 173 static struct task_init task_init_none;
 174
 175 __attribute__((constructor)) static void reg_task_irq(void)
 176 {
 177         reg_task(&task_init_irq);
 178 }