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1// SPDX-License-Identifier: GPL-2.02/* Copyright (c) 2021 Facebook */3#include "vmlinux.h"4#include <bpf/bpf_helpers.h>5#include <bpf/bpf_tracing.h>6 7char _license[] SEC("license") = "GPL";8 9__u64 test1_hits = 0;10__u64 address_low = 0;11__u64 address_high = 0;12int wasted_entries = 0;13long total_entries = 0;14 15#define ENTRY_CNT 3216struct perf_branch_entry entries[ENTRY_CNT] = {};17 18static inline bool gbs_in_range(__u64 val)19{20 return (val >= address_low) && (val < address_high);21}22 23SEC("fexit/bpf_testmod_loop_test")24int BPF_PROG(test1, int n, int ret)25{26 long i;27 28 total_entries = bpf_get_branch_snapshot(entries, sizeof(entries), 0);29 total_entries /= sizeof(struct perf_branch_entry);30 31 for (i = 0; i < ENTRY_CNT; i++) {32 if (i >= total_entries)33 break;34 if (gbs_in_range(entries[i].from) && gbs_in_range(entries[i].to))35 test1_hits++;36 else if (!test1_hits)37 wasted_entries++;38 }39 return 0;40}41