1// SPDX-License-Identifier: GPL-2.0
2/* Copyright (C) 2023. Huawei Technologies Co., Ltd */
3#include <stdbool.h>
4#include <errno.h>
5#include <linux/types.h>
6#include <linux/bpf.h>
7#include <bpf/bpf_helpers.h>
8#include <bpf/bpf_tracing.h>
9
10#define OP_BATCH 64
11
12struct update_ctx {
13 unsigned int from;
14 unsigned int step;
15};
16
17struct {
18 __uint(type, BPF_MAP_TYPE_HASH);
19 __uint(key_size, 4);
20 __uint(map_flags, BPF_F_NO_PREALLOC);
21} htab SEC(".maps");
22
23char _license[] SEC("license") = "GPL";
24
25unsigned char zeroed_value[4096];
26unsigned int nr_thread = 0;
27long op_cnt = 0;
28
29static int write_htab(unsigned int i, struct update_ctx *ctx, unsigned int flags)
30{
31 bpf_map_update_elem(&htab, &ctx->from, zeroed_value, flags);
32 ctx->from += ctx->step;
33
34 return 0;
35}
36
37static int overwrite_htab(unsigned int i, struct update_ctx *ctx)
38{
39 return write_htab(i, ctx, flags: 0);
40}
41
42static int newwrite_htab(unsigned int i, struct update_ctx *ctx)
43{
44 return write_htab(i, ctx, flags: BPF_NOEXIST);
45}
46
47static int del_htab(unsigned int i, struct update_ctx *ctx)
48{
49 bpf_map_delete_elem(&htab, &ctx->from);
50 ctx->from += ctx->step;
51
52 return 0;
53}
54
55SEC("?tp/syscalls/sys_enter_getpgid")
56int overwrite(void *ctx)
57{
58 struct update_ctx update;
59
60 update.from = bpf_get_smp_processor_id();
61 update.step = nr_thread;
62 bpf_loop(OP_BATCH, overwrite_htab, &update, 0);
63 __sync_fetch_and_add(&op_cnt, 1);
64 return 0;
65}
66
67SEC("?tp/syscalls/sys_enter_getpgid")
68int batch_add_batch_del(void *ctx)
69{
70 struct update_ctx update;
71
72 update.from = bpf_get_smp_processor_id();
73 update.step = nr_thread;
74 bpf_loop(OP_BATCH, overwrite_htab, &update, 0);
75
76 update.from = bpf_get_smp_processor_id();
77 bpf_loop(OP_BATCH, del_htab, &update, 0);
78
79 __sync_fetch_and_add(&op_cnt, 2);
80 return 0;
81}
82
83SEC("?tp/syscalls/sys_enter_getpgid")
84int add_only(void *ctx)
85{
86 struct update_ctx update;
87
88 update.from = bpf_get_smp_processor_id() / 2;
89 update.step = nr_thread / 2;
90 bpf_loop(OP_BATCH, newwrite_htab, &update, 0);
91 __sync_fetch_and_add(&op_cnt, 1);
92 return 0;
93}
94
95SEC("?tp/syscalls/sys_enter_getppid")
96int del_only(void *ctx)
97{
98 struct update_ctx update;
99
100 update.from = bpf_get_smp_processor_id() / 2;
101 update.step = nr_thread / 2;
102 bpf_loop(OP_BATCH, del_htab, &update, 0);
103 __sync_fetch_and_add(&op_cnt, 1);
104 return 0;
105}
106

source code of linux/tools/testing/selftests/bpf/progs/htab_mem_bench.c