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a1270fe9 | 1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* Copyright (c) 2019 Facebook | |
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 Managment | |
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 | |
ffd81558 | 19 | * --no_cn Do not return cn notifications |
a1270fe9 | 20 | * -r <rate> Rate limit in Mbps |
21 | * -s Get HBM stats (marked, dropped, etc.) | |
5b4f21b2 | 22 | * -t <time> Exit after specified seconds (default is 0) |
a1270fe9 | 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 | * Currrently only supported for egress. | |
28 | * -h Print this info | |
29 | * prog BPF program file name. Name defaults to hbm_out_kern.o | |
30 | */ | |
31 | ||
32 | #define _GNU_SOURCE | |
33 | ||
34 | #include <stdio.h> | |
35 | #include <stdlib.h> | |
36 | #include <assert.h> | |
37 | #include <sys/resource.h> | |
38 | #include <sys/time.h> | |
39 | #include <unistd.h> | |
40 | #include <errno.h> | |
41 | #include <fcntl.h> | |
42 | #include <linux/unistd.h> | |
43 | ||
44 | #include <linux/bpf.h> | |
45 | #include <bpf/bpf.h> | |
ffd81558 | 46 | #include <getopt.h> |
a1270fe9 | 47 | |
48 | #include "bpf_load.h" | |
49 | #include "bpf_rlimit.h" | |
50 | #include "cgroup_helpers.h" | |
51 | #include "hbm.h" | |
52 | #include "bpf_util.h" | |
4d18f6de DL |
53 | #include "bpf.h" |
54 | #include "libbpf.h" | |
a1270fe9 | 55 | |
56 | bool outFlag = true; | |
57 | int minRate = 1000; /* cgroup rate limit in Mbps */ | |
58 | int rate = 1000; /* can grow if rate conserving is enabled */ | |
59 | int dur = 1; | |
60 | bool stats_flag; | |
61 | bool loopback_flag; | |
62 | bool debugFlag; | |
63 | bool work_conserving_flag; | |
ffd81558 | 64 | bool no_cn_flag; |
71634d7f | 65 | bool edt_flag; |
a1270fe9 | 66 | |
67 | static void Usage(void); | |
68 | static void read_trace_pipe2(void); | |
69 | static void do_error(char *msg, bool errno_flag); | |
70 | ||
71 | #define DEBUGFS "/sys/kernel/debug/tracing/" | |
72 | ||
73 | struct bpf_object *obj; | |
74 | int bpfprog_fd; | |
75 | int cgroup_storage_fd; | |
76 | ||
77 | static void read_trace_pipe2(void) | |
78 | { | |
79 | int trace_fd; | |
80 | FILE *outf; | |
81 | char *outFname = "hbm_out.log"; | |
82 | ||
83 | trace_fd = open(DEBUGFS "trace_pipe", O_RDONLY, 0); | |
84 | if (trace_fd < 0) { | |
85 | printf("Error opening trace_pipe\n"); | |
86 | return; | |
87 | } | |
88 | ||
89 | // Future support of ingress | |
90 | // if (!outFlag) | |
91 | // outFname = "hbm_in.log"; | |
92 | outf = fopen(outFname, "w"); | |
93 | ||
94 | if (outf == NULL) | |
95 | printf("Error creating %s\n", outFname); | |
96 | ||
97 | while (1) { | |
98 | static char buf[4097]; | |
99 | ssize_t sz; | |
100 | ||
101 | sz = read(trace_fd, buf, sizeof(buf) - 1); | |
102 | if (sz > 0) { | |
103 | buf[sz] = 0; | |
104 | puts(buf); | |
105 | if (outf != NULL) { | |
106 | fprintf(outf, "%s\n", buf); | |
107 | fflush(outf); | |
108 | } | |
109 | } | |
110 | } | |
111 | } | |
112 | ||
113 | static void do_error(char *msg, bool errno_flag) | |
114 | { | |
115 | if (errno_flag) | |
116 | printf("ERROR: %s, errno: %d\n", msg, errno); | |
117 | else | |
118 | printf("ERROR: %s\n", msg); | |
119 | exit(1); | |
120 | } | |
121 | ||
122 | static int prog_load(char *prog) | |
123 | { | |
124 | struct bpf_prog_load_attr prog_load_attr = { | |
125 | .prog_type = BPF_PROG_TYPE_CGROUP_SKB, | |
126 | .file = prog, | |
127 | .expected_attach_type = BPF_CGROUP_INET_EGRESS, | |
128 | }; | |
129 | int map_fd; | |
130 | struct bpf_map *map; | |
131 | ||
132 | int ret = 0; | |
133 | ||
134 | if (access(prog, O_RDONLY) < 0) { | |
135 | printf("Error accessing file %s: %s\n", prog, strerror(errno)); | |
136 | return 1; | |
137 | } | |
138 | if (bpf_prog_load_xattr(&prog_load_attr, &obj, &bpfprog_fd)) | |
139 | ret = 1; | |
140 | if (!ret) { | |
141 | map = bpf_object__find_map_by_name(obj, "queue_stats"); | |
142 | map_fd = bpf_map__fd(map); | |
143 | if (map_fd < 0) { | |
144 | printf("Map not found: %s\n", strerror(map_fd)); | |
145 | ret = 1; | |
146 | } | |
147 | } | |
148 | ||
149 | if (ret) { | |
150 | printf("ERROR: load_bpf_file failed for: %s\n", prog); | |
151 | printf(" Output from verifier:\n%s\n------\n", bpf_log_buf); | |
152 | ret = -1; | |
153 | } else { | |
154 | ret = map_fd; | |
155 | } | |
156 | ||
157 | return ret; | |
158 | } | |
159 | ||
160 | static int run_bpf_prog(char *prog, int cg_id) | |
161 | { | |
162 | int map_fd; | |
163 | int rc = 0; | |
164 | int key = 0; | |
165 | int cg1 = 0; | |
166 | int type = BPF_CGROUP_INET_EGRESS; | |
167 | char cg_dir[100]; | |
168 | struct hbm_queue_stats qstats = {0}; | |
169 | ||
170 | sprintf(cg_dir, "/hbm%d", cg_id); | |
171 | map_fd = prog_load(prog); | |
172 | if (map_fd == -1) | |
173 | return 1; | |
174 | ||
175 | if (setup_cgroup_environment()) { | |
176 | printf("ERROR: setting cgroup environment\n"); | |
177 | goto err; | |
178 | } | |
179 | cg1 = create_and_get_cgroup(cg_dir); | |
180 | if (!cg1) { | |
181 | printf("ERROR: create_and_get_cgroup\n"); | |
182 | goto err; | |
183 | } | |
184 | if (join_cgroup(cg_dir)) { | |
185 | printf("ERROR: join_cgroup\n"); | |
186 | goto err; | |
187 | } | |
188 | ||
189 | qstats.rate = rate; | |
190 | qstats.stats = stats_flag ? 1 : 0; | |
191 | qstats.loopback = loopback_flag ? 1 : 0; | |
ffd81558 | 192 | qstats.no_cn = no_cn_flag ? 1 : 0; |
a1270fe9 | 193 | if (bpf_map_update_elem(map_fd, &key, &qstats, BPF_ANY)) { |
194 | printf("ERROR: Could not update map element\n"); | |
195 | goto err; | |
196 | } | |
197 | ||
198 | if (!outFlag) | |
199 | type = BPF_CGROUP_INET_INGRESS; | |
200 | if (bpf_prog_attach(bpfprog_fd, cg1, type, 0)) { | |
201 | printf("ERROR: bpf_prog_attach fails!\n"); | |
202 | log_err("Attaching prog"); | |
203 | goto err; | |
204 | } | |
205 | ||
206 | if (work_conserving_flag) { | |
207 | struct timeval t0, t_last, t_new; | |
208 | FILE *fin; | |
209 | unsigned long long last_eth_tx_bytes, new_eth_tx_bytes; | |
210 | signed long long last_cg_tx_bytes, new_cg_tx_bytes; | |
211 | signed long long delta_time, delta_bytes, delta_rate; | |
212 | int delta_ms; | |
213 | #define DELTA_RATE_CHECK 10000 /* in us */ | |
214 | #define RATE_THRESHOLD 9500000000 /* 9.5 Gbps */ | |
215 | ||
216 | bpf_map_lookup_elem(map_fd, &key, &qstats); | |
217 | if (gettimeofday(&t0, NULL) < 0) | |
218 | do_error("gettimeofday failed", true); | |
219 | t_last = t0; | |
220 | fin = fopen("/sys/class/net/eth0/statistics/tx_bytes", "r"); | |
221 | if (fscanf(fin, "%llu", &last_eth_tx_bytes) != 1) | |
222 | do_error("fscanf fails", false); | |
223 | fclose(fin); | |
224 | last_cg_tx_bytes = qstats.bytes_total; | |
225 | while (true) { | |
226 | usleep(DELTA_RATE_CHECK); | |
227 | if (gettimeofday(&t_new, NULL) < 0) | |
228 | do_error("gettimeofday failed", true); | |
229 | delta_ms = (t_new.tv_sec - t0.tv_sec) * 1000 + | |
230 | (t_new.tv_usec - t0.tv_usec)/1000; | |
231 | if (delta_ms > dur * 1000) | |
232 | break; | |
233 | delta_time = (t_new.tv_sec - t_last.tv_sec) * 1000000 + | |
234 | (t_new.tv_usec - t_last.tv_usec); | |
235 | if (delta_time == 0) | |
236 | continue; | |
237 | t_last = t_new; | |
238 | fin = fopen("/sys/class/net/eth0/statistics/tx_bytes", | |
239 | "r"); | |
240 | if (fscanf(fin, "%llu", &new_eth_tx_bytes) != 1) | |
241 | do_error("fscanf fails", false); | |
242 | fclose(fin); | |
243 | printf(" new_eth_tx_bytes:%llu\n", | |
244 | new_eth_tx_bytes); | |
245 | bpf_map_lookup_elem(map_fd, &key, &qstats); | |
246 | new_cg_tx_bytes = qstats.bytes_total; | |
247 | delta_bytes = new_eth_tx_bytes - last_eth_tx_bytes; | |
248 | last_eth_tx_bytes = new_eth_tx_bytes; | |
249 | delta_rate = (delta_bytes * 8000000) / delta_time; | |
250 | printf("%5d - eth_rate:%.1fGbps cg_rate:%.3fGbps", | |
251 | delta_ms, delta_rate/1000000000.0, | |
252 | rate/1000.0); | |
253 | if (delta_rate < RATE_THRESHOLD) { | |
254 | /* can increase cgroup rate limit, but first | |
255 | * check if we are using the current limit. | |
256 | * Currently increasing by 6.25%, unknown | |
257 | * if that is the optimal rate. | |
258 | */ | |
259 | int rate_diff100; | |
260 | ||
261 | delta_bytes = new_cg_tx_bytes - | |
262 | last_cg_tx_bytes; | |
263 | last_cg_tx_bytes = new_cg_tx_bytes; | |
264 | delta_rate = (delta_bytes * 8000000) / | |
265 | delta_time; | |
266 | printf(" rate:%.3fGbps", | |
267 | delta_rate/1000000000.0); | |
268 | rate_diff100 = (((long long)rate)*1000000 - | |
269 | delta_rate) * 100 / | |
270 | (((long long) rate) * 1000000); | |
271 | printf(" rdiff:%d", rate_diff100); | |
272 | if (rate_diff100 <= 3) { | |
273 | rate += (rate >> 4); | |
274 | if (rate > RATE_THRESHOLD / 1000000) | |
275 | rate = RATE_THRESHOLD / 1000000; | |
276 | qstats.rate = rate; | |
277 | printf(" INC\n"); | |
278 | } else { | |
279 | printf("\n"); | |
280 | } | |
281 | } else { | |
282 | /* Need to decrease cgroup rate limit. | |
283 | * Currently decreasing by 12.5%, unknown | |
284 | * if that is optimal | |
285 | */ | |
286 | printf(" DEC\n"); | |
287 | rate -= (rate >> 3); | |
288 | if (rate < minRate) | |
289 | rate = minRate; | |
290 | qstats.rate = rate; | |
291 | } | |
292 | if (bpf_map_update_elem(map_fd, &key, &qstats, BPF_ANY)) | |
293 | do_error("update map element fails", false); | |
294 | } | |
295 | } else { | |
296 | sleep(dur); | |
297 | } | |
298 | // Get stats! | |
299 | if (stats_flag && bpf_map_lookup_elem(map_fd, &key, &qstats)) { | |
300 | char fname[100]; | |
301 | FILE *fout; | |
302 | ||
303 | if (!outFlag) | |
304 | sprintf(fname, "hbm.%d.in", cg_id); | |
305 | else | |
306 | sprintf(fname, "hbm.%d.out", cg_id); | |
307 | fout = fopen(fname, "w"); | |
308 | fprintf(fout, "id:%d\n", cg_id); | |
309 | fprintf(fout, "ERROR: Could not lookup queue_stats\n"); | |
310 | } else if (stats_flag && qstats.lastPacketTime > | |
311 | qstats.firstPacketTime) { | |
312 | long long delta_us = (qstats.lastPacketTime - | |
313 | qstats.firstPacketTime)/1000; | |
314 | unsigned int rate_mbps = ((qstats.bytes_total - | |
315 | qstats.bytes_dropped) * 8 / | |
316 | delta_us); | |
317 | double percent_pkts, percent_bytes; | |
318 | char fname[100]; | |
319 | FILE *fout; | |
d58c6f72 | 320 | int k; |
321 | static const char *returnValNames[] = { | |
322 | "DROP_PKT", | |
323 | "ALLOW_PKT", | |
324 | "DROP_PKT_CWR", | |
325 | "ALLOW_PKT_CWR" | |
326 | }; | |
327 | #define RET_VAL_COUNT 4 | |
a1270fe9 | 328 | |
329 | // Future support of ingress | |
330 | // if (!outFlag) | |
331 | // sprintf(fname, "hbm.%d.in", cg_id); | |
332 | // else | |
333 | sprintf(fname, "hbm.%d.out", cg_id); | |
334 | fout = fopen(fname, "w"); | |
335 | fprintf(fout, "id:%d\n", cg_id); | |
336 | fprintf(fout, "rate_mbps:%d\n", rate_mbps); | |
337 | fprintf(fout, "duration:%.1f secs\n", | |
338 | (qstats.lastPacketTime - qstats.firstPacketTime) / | |
339 | 1000000000.0); | |
340 | fprintf(fout, "packets:%d\n", (int)qstats.pkts_total); | |
341 | fprintf(fout, "bytes_MB:%d\n", (int)(qstats.bytes_total / | |
342 | 1000000)); | |
343 | fprintf(fout, "pkts_dropped:%d\n", (int)qstats.pkts_dropped); | |
344 | fprintf(fout, "bytes_dropped_MB:%d\n", | |
345 | (int)(qstats.bytes_dropped / | |
346 | 1000000)); | |
347 | // Marked Pkts and Bytes | |
348 | percent_pkts = (qstats.pkts_marked * 100.0) / | |
349 | (qstats.pkts_total + 1); | |
350 | percent_bytes = (qstats.bytes_marked * 100.0) / | |
351 | (qstats.bytes_total + 1); | |
352 | fprintf(fout, "pkts_marked_percent:%6.2f\n", percent_pkts); | |
353 | fprintf(fout, "bytes_marked_percent:%6.2f\n", percent_bytes); | |
354 | ||
355 | // Dropped Pkts and Bytes | |
356 | percent_pkts = (qstats.pkts_dropped * 100.0) / | |
357 | (qstats.pkts_total + 1); | |
358 | percent_bytes = (qstats.bytes_dropped * 100.0) / | |
359 | (qstats.bytes_total + 1); | |
360 | fprintf(fout, "pkts_dropped_percent:%6.2f\n", percent_pkts); | |
361 | fprintf(fout, "bytes_dropped_percent:%6.2f\n", percent_bytes); | |
d58c6f72 | 362 | |
363 | // ECN CE markings | |
364 | percent_pkts = (qstats.pkts_ecn_ce * 100.0) / | |
365 | (qstats.pkts_total + 1); | |
366 | fprintf(fout, "pkts_ecn_ce:%6.2f (%d)\n", percent_pkts, | |
367 | (int)qstats.pkts_ecn_ce); | |
368 | ||
369 | // Average cwnd | |
370 | fprintf(fout, "avg cwnd:%d\n", | |
371 | (int)(qstats.sum_cwnd / (qstats.sum_cwnd_cnt + 1))); | |
372 | // Average rtt | |
373 | fprintf(fout, "avg rtt:%d\n", | |
374 | (int)(qstats.sum_rtt / (qstats.pkts_total + 1))); | |
375 | // Average credit | |
71634d7f | 376 | if (edt_flag) |
377 | fprintf(fout, "avg credit_ms:%.03f\n", | |
378 | (qstats.sum_credit / | |
379 | (qstats.pkts_total + 1.0)) / 1000000.0); | |
380 | else | |
381 | fprintf(fout, "avg credit:%d\n", | |
382 | (int)(qstats.sum_credit / | |
383 | (1500 * ((int)qstats.pkts_total ) + 1))); | |
d58c6f72 | 384 | |
385 | // Return values stats | |
386 | for (k = 0; k < RET_VAL_COUNT; k++) { | |
387 | percent_pkts = (qstats.returnValCount[k] * 100.0) / | |
388 | (qstats.pkts_total + 1); | |
389 | fprintf(fout, "%s:%6.2f (%d)\n", returnValNames[k], | |
390 | percent_pkts, (int)qstats.returnValCount[k]); | |
391 | } | |
a1270fe9 | 392 | fclose(fout); |
393 | } | |
394 | ||
395 | if (debugFlag) | |
396 | read_trace_pipe2(); | |
397 | return rc; | |
398 | err: | |
399 | rc = 1; | |
400 | ||
401 | if (cg1) | |
402 | close(cg1); | |
403 | cleanup_cgroup_environment(); | |
404 | ||
405 | return rc; | |
406 | } | |
407 | ||
408 | static void Usage(void) | |
409 | { | |
410 | printf("This program loads a cgroup skb BPF program to enforce\n" | |
411 | "cgroup output (egress) bandwidth limits.\n\n" | |
ffd81558 | 412 | "USAGE: hbm [-o] [-d] [-l] [-n <id>] [--no_cn] [-r <rate>]\n" |
413 | " [-s] [-t <secs>] [-w] [-h] [prog]\n" | |
a1270fe9 | 414 | " Where:\n" |
415 | " -o indicates egress direction (default)\n" | |
416 | " -d print BPF trace debug buffer\n" | |
71634d7f | 417 | " --edt use fq's Earliest Departure Time\n" |
a1270fe9 | 418 | " -l also limit flows using loopback\n" |
419 | " -n <#> to create cgroup \"/hbm#\" and attach prog\n" | |
420 | " Default is /hbm1\n" | |
2ed99339 | 421 | " --no_cn disable CN notifications\n" |
a1270fe9 | 422 | " -r <rate> Rate in Mbps\n" |
423 | " -s Update HBM stats\n" | |
5b4f21b2 | 424 | " -t <time> Exit after specified seconds (default is 0)\n" |
a1270fe9 | 425 | " -w Work conserving flag. cgroup can increase\n" |
426 | " bandwidth beyond the rate limit specified\n" | |
427 | " while there is available bandwidth. Current\n" | |
428 | " implementation assumes there is only eth0\n" | |
429 | " but can be extended to support multiple NICs\n" | |
430 | " -h print this info\n" | |
431 | " prog BPF program file name. Name defaults to\n" | |
432 | " hbm_out_kern.o\n"); | |
433 | } | |
434 | ||
435 | int main(int argc, char **argv) | |
436 | { | |
437 | char *prog = "hbm_out_kern.o"; | |
438 | int k; | |
439 | int cg_id = 1; | |
440 | char *optstring = "iodln:r:st:wh"; | |
ffd81558 | 441 | struct option loptions[] = { |
442 | {"no_cn", 0, NULL, 1}, | |
71634d7f | 443 | {"edt", 0, NULL, 2}, |
ffd81558 | 444 | {NULL, 0, NULL, 0} |
445 | }; | |
a1270fe9 | 446 | |
ffd81558 | 447 | while ((k = getopt_long(argc, argv, optstring, loptions, NULL)) != -1) { |
a1270fe9 | 448 | switch (k) { |
ffd81558 | 449 | case 1: |
450 | no_cn_flag = true; | |
451 | break; | |
71634d7f | 452 | case 2: |
453 | prog = "hbm_edt_kern.o"; | |
454 | edt_flag = true; | |
455 | break; | |
a1270fe9 | 456 | case'o': |
457 | break; | |
458 | case 'd': | |
459 | debugFlag = true; | |
460 | break; | |
461 | case 'l': | |
462 | loopback_flag = true; | |
463 | break; | |
464 | case 'n': | |
465 | cg_id = atoi(optarg); | |
466 | break; | |
467 | case 'r': | |
468 | minRate = atoi(optarg) * 1.024; | |
469 | rate = minRate; | |
470 | break; | |
471 | case 's': | |
472 | stats_flag = true; | |
473 | break; | |
474 | case 't': | |
475 | dur = atoi(optarg); | |
476 | break; | |
477 | case 'w': | |
478 | work_conserving_flag = true; | |
479 | break; | |
480 | case '?': | |
481 | if (optopt == 'n' || optopt == 'r' || optopt == 't') | |
482 | fprintf(stderr, | |
483 | "Option -%c requires an argument.\n\n", | |
484 | optopt); | |
485 | case 'h': | |
486 | // fallthrough | |
487 | default: | |
488 | Usage(); | |
489 | return 0; | |
490 | } | |
491 | } | |
492 | ||
493 | if (optind < argc) | |
494 | prog = argv[optind]; | |
495 | printf("HBM prog: %s\n", prog != NULL ? prog : "NULL"); | |
496 | ||
497 | return run_bpf_prog(prog, cg_id); | |
498 | } |