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
12 struct update_ctx {
13 unsigned int from;
14 unsigned int step;
15 };
16
17 struct {
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
23 char _license[] SEC("license") = "GPL";
24
25 unsigned char zeroed_value[4096];
26 unsigned int nr_thread = 0;
27 long op_cnt = 0;
28
write_htab(unsigned int i,struct update_ctx * ctx,unsigned int flags)29 static 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
overwrite_htab(unsigned int i,struct update_ctx * ctx)37 static int overwrite_htab(unsigned int i, struct update_ctx *ctx)
38 {
39 return write_htab(i, ctx, 0);
40 }
41
newwrite_htab(unsigned int i,struct update_ctx * ctx)42 static int newwrite_htab(unsigned int i, struct update_ctx *ctx)
43 {
44 return write_htab(i, ctx, BPF_NOEXIST);
45 }
46
del_htab(unsigned int i,struct update_ctx * ctx)47 static 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
55 SEC("?tp/syscalls/sys_enter_getpgid")
overwrite(void * ctx)56 int 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
67 SEC("?tp/syscalls/sys_enter_getpgid")
batch_add_batch_del(void * ctx)68 int 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
83 SEC("?tp/syscalls/sys_enter_getpgid")
add_only(void * ctx)84 int 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
95 SEC("?tp/syscalls/sys_enter_getppid")
del_only(void * ctx)96 int 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