| 1 | |
| 2 | |
| 3 | *
|
| 4 | * This program is free software; you can redistribute it and/or
|
| 5 | * modify it under the terms of version 2 of the GNU General Public
|
| 6 | * License as published by the Free Software Foundation.
|
| 7 | *
|
| 8 | * Example program for Host Bandwidth Management
|
| 9 | *
|
| 10 | * This program loads a cgroup skb BPF program to enforce cgroup output
|
| 11 | * (egress) or input (ingress) bandwidth limits.
|
| 12 | *
|
| 13 | * USAGE: hbm [-d] [-l] [-n <id>] [-r <rate>] [-s] [-t <secs>] [-w] [-h] [prog]
|
| 14 | * Where:
|
| 15 | * -d Print BPF trace debug buffer
|
| 16 | * -l Also limit flows doing loopback
|
| 17 | * -n <#> To create cgroup \"/hbm#\" and attach prog
|
| 18 | * Default is /hbm1
|
| 19 | * --no_cn Do not return cn notifications
|
| 20 | * -r <rate> Rate limit in Mbps
|
| 21 | * -s Get HBM stats (marked, dropped, etc.)
|
| 22 | * -t <time> Exit after specified seconds (default is 0)
|
| 23 | * -w Work conserving flag. cgroup can increase its bandwidth
|
| 24 | * beyond the rate limit specified while there is available
|
| 25 | * bandwidth. Current implementation assumes there is only
|
| 26 | * NIC (eth0), but can be extended to support multiple NICs.
|
| 27 | * Currently only supported for egress.
|
| 28 | * -h Print this info
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| 29 | * prog BPF program file name. Name defaults to hbm_out_kern.o
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| 30 |
|
| 31 |
|
| 32 | #define _GNU_SOURCE
|
| 33 |
|
| 34 | #include <stdio.h>
|
| 35 | #include <stdlib.h>
|
| 36 | #include <assert.h>
|
| 37 | #include <sys/time.h>
|
| 38 | #include <unistd.h>
|
| 39 | #include <errno.h>
|
| 40 | #include <fcntl.h>
|
| 41 | #include <linux/unistd.h>
|
| 42 | #include <linux/compiler.h>
|
| 43 |
|
| 44 | #include <linux/bpf.h>
|
| 45 | #include <bpf/bpf.h>
|
| 46 | #include <getopt.h>
|
| 47 |
|
| 48 | #include "cgroup_helpers.h"
|
| 49 | #include "hbm.h"
|
| 50 | #include "bpf_util.h"
|
| 51 | #include <bpf/libbpf.h>
|
| 52 |
|
| 53 | bool outFlag = true;
|
| 54 | int minRate = 1000;
|
| 55 | int rate = 1000;
|
| 56 | int dur = 1;
|
| 57 | bool stats_flag;
|
| 58 | bool loopback_flag;
|
| 59 | bool debugFlag;
|
| 60 | bool work_conserving_flag;
|
| 61 | bool no_cn_flag;
|
| 62 | bool edt_flag;
|
| 63 |
|
| 64 | static void Usage(void);
|
| 65 | static void read_trace_pipe2(void);
|
| 66 | static void do_error(char *msg, bool errno_flag);
|
| 67 |
|
| 68 | #define TRACEFS "/sys/kernel/tracing/"
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| 69 |
|
| 70 | static struct bpf_program *bpf_prog;
|
| 71 | static struct bpf_object *obj;
|
| 72 | static int queue_stats_fd;
|
| 73 |
|
| 74 | static void read_trace_pipe2(void)
|
| 75 | {
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| 76 | int trace_fd;
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| 77 | FILE *outf;
|
| 78 | char *outFname = "hbm_out.log";
|
| 79 |
|
| 80 | trace_fd = open(TRACEFS "trace_pipe", O_RDONLY, 0);
|
| 81 | if (trace_fd < 0) {
|
| 82 | printf("Error opening trace_pipe\n");
|
| 83 | return;
|
| 84 | }
|
| 85 |
|
| 86 | |
| 87 | |
| 88 | |
| 89 | outf = fopen(outFname, "w");
|
| 90 |
|
| 91 | if (outf == NULL)
|
| 92 | printf("Error creating %s\n", outFname);
|
| 93 |
|
| 94 | while (1) {
|
| 95 | static char buf[4097];
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| 96 | ssize_t sz;
|
| 97 |
|
| 98 | sz = read(trace_fd, buf, sizeof(buf) - 1);
|
| 99 | if (sz > 0) {
|
| 100 | buf[sz] = 0;
|
| 101 | puts(buf);
|
| 102 | if (outf != NULL) {
|
| 103 | fprintf(outf, "%s\n", buf);
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| 104 | fflush(outf);
|
| 105 | }
|
| 106 | }
|
| 107 | }
|
| 108 | }
|
| 109 |
|
| 110 | static void do_error(char *msg, bool errno_flag)
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| 111 | {
|
| 112 | if (errno_flag)
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| 113 | printf("ERROR: %s, errno: %d\n", msg, errno);
|
| 114 | else
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| 115 | printf("ERROR: %s\n", msg);
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| 116 | exit(1);
|
| 117 | }
|
| 118 |
|
| 119 | static int prog_load(char *prog)
|
| 120 | {
|
| 121 | struct bpf_program *pos;
|
| 122 | const char *sec_name;
|
| 123 |
|
| 124 | obj = bpf_object__open_file(prog, NULL);
|
| 125 | if (libbpf_get_error(obj)) {
|
| 126 | printf("ERROR: opening BPF object file failed\n");
|
| 127 | return 1;
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| 128 | }
|
| 129 |
|
| 130 |
|
| 131 | if (bpf_object__load(obj)) {
|
| 132 | printf("ERROR: loading BPF object file failed\n");
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| 133 | goto err;
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| 134 | }
|
| 135 |
|
| 136 | bpf_object__for_each_program(pos, obj) {
|
| 137 | sec_name = bpf_program__section_name(pos);
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| 138 | if (sec_name && !strcmp(sec_name, "cgroup_skb/egress")) {
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| 139 | bpf_prog = pos;
|
| 140 | break;
|
| 141 | }
|
| 142 | }
|
| 143 | if (!bpf_prog) {
|
| 144 | printf("ERROR: finding a prog in obj file failed\n");
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| 145 | goto err;
|
| 146 | }
|
| 147 |
|
| 148 | queue_stats_fd = bpf_object__find_map_fd_by_name(obj, "queue_stats");
|
| 149 | if (queue_stats_fd < 0) {
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| 150 | printf("ERROR: finding a map in obj file failed\n");
|
| 151 | goto err;
|
| 152 | }
|
| 153 |
|
| 154 | return 0;
|
| 155 |
|
| 156 | err:
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| 157 | bpf_object__close(obj);
|
| 158 | return 1;
|
| 159 | }
|
| 160 |
|
| 161 | static int run_bpf_prog(char *prog, int cg_id)
|
| 162 | {
|
| 163 | struct hbm_queue_stats qstats = {0};
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| 164 | char cg_dir[100], cg_pin_path[100];
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| 165 | struct bpf_link *link = NULL;
|
| 166 | int key = 0;
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| 167 | int cg1 = 0;
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| 168 | int rc = 0;
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| 169 |
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| 170 | sprintf(cg_dir, "/hbm%d", cg_id);
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| 171 | rc = prog_load(prog);
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| 172 | if (rc != 0)
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| 173 | return rc;
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| 174 |
|
| 175 | if (setup_cgroup_environment()) {
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| 176 | printf("ERROR: setting cgroup environment\n");
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| 177 | goto err;
|
| 178 | }
|
| 179 | cg1 = create_and_get_cgroup(cg_dir);
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| 180 | if (!cg1) {
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| 181 | printf("ERROR: create_and_get_cgroup\n");
|
| 182 | goto err;
|
| 183 | }
|
| 184 | if (join_cgroup(cg_dir)) {
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| 185 | printf("ERROR: join_cgroup\n");
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| 186 | goto err;
|
| 187 | }
|
| 188 |
|
| 189 | qstats.rate = rate;
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| 190 | qstats.stats = stats_flag ? 1 : 0;
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| 191 | qstats.loopback = loopback_flag ? 1 : 0;
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| 192 | qstats.no_cn = no_cn_flag ? 1 : 0;
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| 193 | if (bpf_map_update_elem(queue_stats_fd, &key, &qstats, BPF_ANY)) {
|
| 194 | printf("ERROR: Could not update map element\n");
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| 195 | goto err;
|
| 196 | }
|
| 197 |
|
| 198 | if (!outFlag)
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| 199 | bpf_program__set_expected_attach_type(bpf_prog, BPF_CGROUP_INET_INGRESS);
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| 200 |
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| 201 | link = bpf_program__attach_cgroup(bpf_prog, cg1);
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| 202 | if (libbpf_get_error(link)) {
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| 203 | fprintf(stderr, "ERROR: bpf_program__attach_cgroup failed\n");
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| 204 | goto err;
|
| 205 | }
|
| 206 |
|
| 207 | sprintf(cg_pin_path, "/sys/fs/bpf/hbm%d", cg_id);
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| 208 | rc = bpf_link__pin(link, cg_pin_path);
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| 209 | if (rc < 0) {
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| 210 | printf("ERROR: bpf_link__pin failed: %d\n", rc);
|
| 211 | goto err;
|
| 212 | }
|
| 213 |
|
| 214 | if (work_conserving_flag) {
|
| 215 | struct timeval t0, t_last, t_new;
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| 216 | FILE *fin;
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| 217 | unsigned long long last_eth_tx_bytes, new_eth_tx_bytes;
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| 218 | signed long long last_cg_tx_bytes, new_cg_tx_bytes;
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| 219 | signed long long delta_time, delta_bytes, delta_rate;
|
| 220 | int delta_ms;
|
| 221 | #define DELTA_RATE_CHECK 10000
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| 222 | #define RATE_THRESHOLD 9500000000
|
| 223 |
|
| 224 | bpf_map_lookup_elem(queue_stats_fd, &key, &qstats);
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| 225 | if (gettimeofday(&t0, NULL) < 0)
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| 226 | do_error("gettimeofday failed", true);
|
| 227 | t_last = t0;
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| 228 | fin = fopen("/sys/class/net/eth0/statistics/tx_bytes", "r");
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| 229 | if (fscanf(fin, "%llu", &last_eth_tx_bytes) != 1)
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| 230 | do_error("fscanf fails", false);
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| 231 | fclose(fin);
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| 232 | last_cg_tx_bytes = qstats.bytes_total;
|
| 233 | while (true) {
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| 234 | usleep(DELTA_RATE_CHECK);
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| 235 | if (gettimeofday(&t_new, NULL) < 0)
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| 236 | do_error("gettimeofday failed", true);
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| 237 | delta_ms = (t_new.tv_sec - t0.tv_sec) * 1000 +
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| 238 | (t_new.tv_usec - t0.tv_usec)/1000;
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| 239 | if (delta_ms > dur * 1000)
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| 240 | break;
|
| 241 | delta_time = (t_new.tv_sec - t_last.tv_sec) * 1000000 +
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| 242 | (t_new.tv_usec - t_last.tv_usec);
|
| 243 | if (delta_time == 0)
|
| 244 | continue;
|
| 245 | t_last = t_new;
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| 246 | fin = fopen("/sys/class/net/eth0/statistics/tx_bytes",
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| 247 | "r");
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| 248 | if (fscanf(fin, "%llu", &new_eth_tx_bytes) != 1)
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| 249 | do_error("fscanf fails", false);
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| 250 | fclose(fin);
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| 251 | printf(" new_eth_tx_bytes:%llu\n",
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| 252 | new_eth_tx_bytes);
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| 253 | bpf_map_lookup_elem(queue_stats_fd, &key, &qstats);
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| 254 | new_cg_tx_bytes = qstats.bytes_total;
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| 255 | delta_bytes = new_eth_tx_bytes - last_eth_tx_bytes;
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| 256 | last_eth_tx_bytes = new_eth_tx_bytes;
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| 257 | delta_rate = (delta_bytes * 8000000) / delta_time;
|
| 258 | printf("%5d - eth_rate:%.1fGbps cg_rate:%.3fGbps",
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| 259 | delta_ms, delta_rate/1000000000.0,
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| 260 | rate/1000.0);
|
| 261 | if (delta_rate < RATE_THRESHOLD) {
|
| 262 | |
| 263 | * check if we are using the current limit.
|
| 264 | * Currently increasing by 6.25%, unknown
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| 265 | * if that is the optimal rate.
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| 266 |
|
| 267 | int rate_diff100;
|
| 268 |
|
| 269 | delta_bytes = new_cg_tx_bytes -
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| 270 | last_cg_tx_bytes;
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| 271 | last_cg_tx_bytes = new_cg_tx_bytes;
|
| 272 | delta_rate = (delta_bytes * 8000000) /
|
| 273 | delta_time;
|
| 274 | printf(" rate:%.3fGbps",
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| 275 | delta_rate/1000000000.0);
|
| 276 | rate_diff100 = (((long long)rate)*1000000 -
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| 277 | delta_rate) * 100 /
|
| 278 | (((long long) rate) * 1000000);
|
| 279 | printf(" rdiff:%d", rate_diff100);
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| 280 | if (rate_diff100 <= 3) {
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| 281 | rate += (rate >> 4);
|
| 282 | if (rate > RATE_THRESHOLD / 1000000)
|
| 283 | rate = RATE_THRESHOLD / 1000000;
|
| 284 | qstats.rate = rate;
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| 285 | printf(" INC\n");
|
| 286 | } else {
|
| 287 | printf("\n");
|
| 288 | }
|
| 289 | } else {
|
| 290 | |
| 291 | * Currently decreasing by 12.5%, unknown
|
| 292 | * if that is optimal
|
| 293 |
|
| 294 | printf(" DEC\n");
|
| 295 | rate -= (rate >> 3);
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| 296 | if (rate < minRate)
|
| 297 | rate = minRate;
|
| 298 | qstats.rate = rate;
|
| 299 | }
|
| 300 | if (bpf_map_update_elem(queue_stats_fd, &key, &qstats, BPF_ANY))
|
| 301 | do_error("update map element fails", false);
|
| 302 | }
|
| 303 | } else {
|
| 304 | sleep(dur);
|
| 305 | }
|
| 306 | |
| 307 | if (stats_flag && bpf_map_lookup_elem(queue_stats_fd, &key, &qstats)) {
|
| 308 | char fname[100];
|
| 309 | FILE *fout;
|
| 310 |
|
| 311 | if (!outFlag)
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| 312 | sprintf(fname, "hbm.%d.in", cg_id);
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| 313 | else
|
| 314 | sprintf(fname, "hbm.%d.out", cg_id);
|
| 315 | fout = fopen(fname, "w");
|
| 316 | fprintf(fout, "id:%d\n", cg_id);
|
| 317 | fprintf(fout, "ERROR: Could not lookup queue_stats\n");
|
| 318 | fclose(fout);
|
| 319 | } else if (stats_flag && qstats.lastPacketTime >
|
| 320 | qstats.firstPacketTime) {
|
| 321 | long long delta_us = (qstats.lastPacketTime -
|
| 322 | qstats.firstPacketTime)/1000;
|
| 323 | unsigned int rate_mbps = ((qstats.bytes_total -
|
| 324 | qstats.bytes_dropped) * 8 /
|
| 325 | delta_us);
|
| 326 | double percent_pkts, percent_bytes;
|
| 327 | char fname[100];
|
| 328 | FILE *fout;
|
| 329 | int k;
|
| 330 | static const char *returnValNames[] = {
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| 331 | "DROP_PKT",
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| 332 | "ALLOW_PKT",
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| 333 | "DROP_PKT_CWR",
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| 334 | "ALLOW_PKT_CWR"
|
| 335 | };
|
| 336 | #define RET_VAL_COUNT 4
|
| 337 |
|
| 338 | |
| 339 | |
| 340 | |
| 341 | |
| 342 | sprintf(fname, "hbm.%d.out", cg_id);
|
| 343 | fout = fopen(fname, "w");
|
| 344 | fprintf(fout, "id:%d\n", cg_id);
|
| 345 | fprintf(fout, "rate_mbps:%d\n", rate_mbps);
|
| 346 | fprintf(fout, "duration:%.1f secs\n",
|
| 347 | (qstats.lastPacketTime - qstats.firstPacketTime) /
|
| 348 | 1000000000.0);
|
| 349 | fprintf(fout, "packets:%d\n", (int)qstats.pkts_total);
|
| 350 | fprintf(fout, "bytes_MB:%d\n", (int)(qstats.bytes_total /
|
| 351 | 1000000));
|
| 352 | fprintf(fout, "pkts_dropped:%d\n", (int)qstats.pkts_dropped);
|
| 353 | fprintf(fout, "bytes_dropped_MB:%d\n",
|
| 354 | (int)(qstats.bytes_dropped /
|
| 355 | 1000000));
|
| 356 | |
| 357 | percent_pkts = (qstats.pkts_marked * 100.0) /
|
| 358 | (qstats.pkts_total + 1);
|
| 359 | percent_bytes = (qstats.bytes_marked * 100.0) /
|
| 360 | (qstats.bytes_total + 1);
|
| 361 | fprintf(fout, "pkts_marked_percent:%6.2f\n", percent_pkts);
|
| 362 | fprintf(fout, "bytes_marked_percent:%6.2f\n", percent_bytes);
|
| 363 |
|
| 364 | |
| 365 | percent_pkts = (qstats.pkts_dropped * 100.0) /
|
| 366 | (qstats.pkts_total + 1);
|
| 367 | percent_bytes = (qstats.bytes_dropped * 100.0) /
|
| 368 | (qstats.bytes_total + 1);
|
| 369 | fprintf(fout, "pkts_dropped_percent:%6.2f\n", percent_pkts);
|
| 370 | fprintf(fout, "bytes_dropped_percent:%6.2f\n", percent_bytes);
|
| 371 |
|
| 372 | |
| 373 | percent_pkts = (qstats.pkts_ecn_ce * 100.0) /
|
| 374 | (qstats.pkts_total + 1);
|
| 375 | fprintf(fout, "pkts_ecn_ce:%6.2f (%d)\n", percent_pkts,
|
| 376 | (int)qstats.pkts_ecn_ce);
|
| 377 |
|
| 378 | |
| 379 | fprintf(fout, "avg cwnd:%d\n",
|
| 380 | (int)(qstats.sum_cwnd / (qstats.sum_cwnd_cnt + 1)));
|
| 381 | |
| 382 | fprintf(fout, "avg rtt:%d\n",
|
| 383 | (int)(qstats.sum_rtt / (qstats.pkts_total + 1)));
|
| 384 | |
| 385 | if (edt_flag)
|
| 386 | fprintf(fout, "avg credit_ms:%.03f\n",
|
| 387 | (qstats.sum_credit /
|
| 388 | (qstats.pkts_total + 1.0)) / 1000000.0);
|
| 389 | else
|
| 390 | fprintf(fout, "avg credit:%d\n",
|
| 391 | (int)(qstats.sum_credit /
|
| 392 | (1500 * ((int)qstats.pkts_total ) + 1)));
|
| 393 |
|
| 394 | |
| 395 | for (k = 0; k < RET_VAL_COUNT; k++) {
|
| 396 | percent_pkts = (qstats.returnValCount[k] * 100.0) /
|
| 397 | (qstats.pkts_total + 1);
|
| 398 | fprintf(fout, "%s:%6.2f (%d)\n", returnValNames[k],
|
| 399 | percent_pkts, (int)qstats.returnValCount[k]);
|
| 400 | }
|
| 401 | fclose(fout);
|
| 402 | }
|
| 403 |
|
| 404 | if (debugFlag)
|
| 405 | read_trace_pipe2();
|
| 406 | goto cleanup;
|
| 407 |
|
| 408 | err:
|
| 409 | rc = 1;
|
| 410 |
|
| 411 | cleanup:
|
| 412 | bpf_link__destroy(link);
|
| 413 | bpf_object__close(obj);
|
| 414 |
|
| 415 | if (cg1 != -1)
|
| 416 | close(cg1);
|
| 417 |
|
| 418 | if (rc != 0)
|
| 419 | cleanup_cgroup_environment();
|
| 420 | return rc;
|
| 421 | }
|
| 422 |
|
| 423 | static void Usage(void)
|
| 424 | {
|
| 425 | printf("This program loads a cgroup skb BPF program to enforce\n"
|
| 426 | "cgroup output (egress) bandwidth limits.\n\n"
|
| 427 | "USAGE: hbm [-o] [-d] [-l] [-n <id>] [--no_cn] [-r <rate>]\n"
|
| 428 | " [-s] [-t <secs>] [-w] [-h] [prog]\n"
|
| 429 | " Where:\n"
|
| 430 | " -o indicates egress direction (default)\n"
|
| 431 | " -d print BPF trace debug buffer\n"
|
| 432 | " --edt use fq's Earliest Departure Time\n"
|
| 433 | " -l also limit flows using loopback\n"
|
| 434 | " -n <#> to create cgroup \"/hbm#\" and attach prog\n"
|
| 435 | " Default is /hbm1\n"
|
| 436 | " --no_cn disable CN notifications\n"
|
| 437 | " -r <rate> Rate in Mbps\n"
|
| 438 | " -s Update HBM stats\n"
|
| 439 | " -t <time> Exit after specified seconds (default is 0)\n"
|
| 440 | " -w Work conserving flag. cgroup can increase\n"
|
| 441 | " bandwidth beyond the rate limit specified\n"
|
| 442 | " while there is available bandwidth. Current\n"
|
| 443 | " implementation assumes there is only eth0\n"
|
| 444 | " but can be extended to support multiple NICs\n"
|
| 445 | " -h print this info\n"
|
| 446 | " prog BPF program file name. Name defaults to\n"
|
| 447 | " hbm_out_kern.o\n");
|
| 448 | }
|
| 449 |
|
| 450 | int main(int argc, char **argv)
|
| 451 | {
|
| 452 | char *prog = "hbm_out_kern.o";
|
| 453 | int k;
|
| 454 | int cg_id = 1;
|
| 455 | char *optstring = "iodln:r:st:wh";
|
| 456 | struct option loptions[] = {
|
| 457 | {"no_cn", 0, NULL, 1},
|
| 458 | {"edt", 0, NULL, 2},
|
| 459 | {NULL, 0, NULL, 0}
|
| 460 | };
|
| 461 |
|
| 462 | while ((k = getopt_long(argc, argv, optstring, loptions, NULL)) != -1) {
|
| 463 | switch (k) {
|
| 464 | case 1:
|
| 465 | no_cn_flag = true;
|
| 466 | break;
|
| 467 | case 2:
|
| 468 | prog = "hbm_edt_kern.o";
|
| 469 | edt_flag = true;
|
| 470 | break;
|
| 471 | case'o':
|
| 472 | break;
|
| 473 | case 'd':
|
| 474 | debugFlag = true;
|
| 475 | break;
|
| 476 | case 'l':
|
| 477 | loopback_flag = true;
|
| 478 | break;
|
| 479 | case 'n':
|
| 480 | cg_id = atoi(optarg);
|
| 481 | break;
|
| 482 | case 'r':
|
| 483 | minRate = atoi(optarg) * 1.024;
|
| 484 | rate = minRate;
|
| 485 | break;
|
| 486 | case 's':
|
| 487 | stats_flag = true;
|
| 488 | break;
|
| 489 | case 't':
|
| 490 | dur = atoi(optarg);
|
| 491 | break;
|
| 492 | case 'w':
|
| 493 | work_conserving_flag = true;
|
| 494 | break;
|
| 495 | case '?':
|
| 496 | if (optopt == 'n' || optopt == 'r' || optopt == 't')
|
| 497 | fprintf(stderr,
|
| 498 | "Option -%c requires an argument.\n\n",
|
| 499 | optopt);
|
| 500 | case 'h':
|
| 501 | default:
|
| 502 | Usage();
|
| 503 | return 0;
|
| 504 | }
|
| 505 | }
|
| 506 |
|
| 507 | if (optind < argc)
|
| 508 | prog = argv[optind];
|
| 509 | printf("HBM prog: %s\n", prog != NULL ? prog : "NULL");
|
| 510 |
|
| 511 |
|
| 512 | libbpf_set_strict_mode(LIBBPF_STRICT_ALL);
|
| 513 |
|
| 514 | return run_bpf_prog(prog, cg_id);
|
| 515 | }
|