64 lines · c
1// SPDX-License-Identifier: GPL-2.02/* Copyright (c) 2023 Isovalent */3 4#include "vmlinux.h"5 6#include <bpf/bpf_helpers.h>7#include "bpf_misc.h"8 9char _license[] SEC("license") = "GPL";10 11struct {12 __uint(type, BPF_MAP_TYPE_HASH);13} hash_map_bench SEC(".maps");14 15/* The number of slots to store times */16#define NR_SLOTS 3217#define NR_CPUS 25618#define CPU_MASK (NR_CPUS-1)19 20/* Configured by userspace */21u64 nr_entries;22u64 nr_loops;23u32 __attribute__((__aligned__(8))) key[NR_CPUS];24 25/* Filled by us */26u64 __attribute__((__aligned__(256))) percpu_times_index[NR_CPUS];27u64 __attribute__((__aligned__(256))) percpu_times[NR_CPUS][NR_SLOTS];28 29static inline void patch_key(u32 i)30{31#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__32 key[0] = i + 1;33#else34 key[0] = __builtin_bswap32(i + 1);35#endif36 /* the rest of key is random and is configured by userspace */37}38 39static int lookup_callback(__u32 index, u32 *unused)40{41 patch_key(index);42 return bpf_map_lookup_elem(&hash_map_bench, key) ? 0 : 1;43}44 45static int loop_lookup_callback(__u32 index, u32 *unused)46{47 return bpf_loop(nr_entries, lookup_callback, NULL, 0) ? 0 : 1;48}49 50SEC("fentry/" SYS_PREFIX "sys_getpgid")51int benchmark(void *ctx)52{53 u32 cpu = bpf_get_smp_processor_id();54 u32 times_index;55 u64 start_time;56 57 times_index = percpu_times_index[cpu & CPU_MASK] % NR_SLOTS;58 start_time = bpf_ktime_get_ns();59 bpf_loop(nr_loops, loop_lookup_callback, NULL, 0);60 percpu_times[cpu & CPU_MASK][times_index] = bpf_ktime_get_ns() - start_time;61 percpu_times_index[cpu & CPU_MASK] += 1;62 return 0;63}64