tools/testing/selftests/bpf/benchs/bench_bpf_loop.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Copyright (c) 2021 Facebook */
   3
   4 #include <argp.h>
   5 #include "bench.h"
   6 #include "bpf_loop_bench.skel.h"
   7
   8 /* BPF triggering benchmarks */
   9 static struct ctx {
  10         struct bpf_loop_bench *skel;
  11 } ctx;
  12
  13 static struct {
  14         __u32 nr_loops;
  15 } args = {
  16         .nr_loops = 10,
  17 };
  18
  19 enum {
  20         ARG_NR_LOOPS = 4000,
  21 };
  22
  23 static const struct argp_option opts[] = {
  24         { "nr_loops", ARG_NR_LOOPS, "nr_loops", 0,
  25                 "Set number of loops for the bpf_loop helper"},
  26         {},
  27 };
  28
  29 static error_t parse_arg(int key, char *arg, struct argp_state *state)
  30 {
  31         switch (key) {
  32         case ARG_NR_LOOPS:
  33                 args.nr_loops = strtol(arg, NULL, 10);
  34                 break;
  35         default:
  36                 return ARGP_ERR_UNKNOWN;
  37         }
  38
  39         return 0;
  40 }
  41
  42 /* exported into benchmark runner */
  43 const struct argp bench_bpf_loop_argp = {
  44         .options = opts,
  45         .parser = parse_arg,
  46 };
  47
  48 static void validate(void)
  49 {
  50         if (env.consumer_cnt != 0) {
  51                 fprintf(stderr, "benchmark doesn't support consumer!\n");
  52                 exit(1);
  53         }
  54 }
  55
  56 static void *producer(void *input)
  57 {
  58         while (true)
  59                 /* trigger the bpf program */
  60                 syscall(__NR_getpgid);
  61
  62         return NULL;
  63 }
  64
  65 static void measure(struct bench_res *res)
  66 {
  67         res->hits = atomic_swap(&ctx.skel->bss->hits, 0);
  68 }
  69
  70 static void setup(void)
  71 {
  72         struct bpf_link *link;
  73
  74         setup_libbpf();
  75
  76         ctx.skel = bpf_loop_bench__open_and_load();
  77         if (!ctx.skel) {
  78                 fprintf(stderr, "failed to open skeleton\n");
  79                 exit(1);
  80         }
  81
  82         link = bpf_program__attach(ctx.skel->progs.benchmark);
  83         if (!link) {
  84                 fprintf(stderr, "failed to attach program!\n");
  85                 exit(1);
  86         }
  87
  88         ctx.skel->bss->nr_loops = args.nr_loops;
  89 }
  90
  91 const struct bench bench_bpf_loop = {
  92         .name = "bpf-loop",
  93         .argp = &bench_bpf_loop_argp,
  94         .validate = validate,
  95         .setup = setup,
  96         .producer_thread = producer,
  97         .measure = measure,
  98         .report_progress = ops_report_progress,
  99         .report_final = ops_report_final,
 100 };