1// SPDX-License-Identifier: GPL-2.0
2#include <subcmd/parse-options.h>
3#include "bench.h"
4
5#include <uapi/linux/filter.h>
6#include <sys/types.h>
7#include <sys/time.h>
8#include <linux/unistd.h>
9#include <sys/syscall.h>
10#include <sys/ioctl.h>
11#include <linux/time64.h>
12#include <uapi/linux/seccomp.h>
13#include <sys/prctl.h>
14
15#include <unistd.h>
16#include <limits.h>
17#include <stddef.h>
18#include <stdint.h>
19#include <stdio.h>
20#include <stdlib.h>
21#include <signal.h>
22#include <sys/wait.h>
23#include <string.h>
24#include <errno.h>
25#include <err.h>
26#include <inttypes.h>
27
28#define LOOPS_DEFAULT 1000000UL
29static uint64_t loops = LOOPS_DEFAULT;
30static bool sync_mode;
31
32static const struct option options[] = {
33 OPT_U64('l', "loop", &loops, "Specify number of loops"),
34 OPT_BOOLEAN('s', "sync-mode", &sync_mode,
35 "Enable the synchronous mode for seccomp notifications"),
36 OPT_END()
37};
38
39static const char * const bench_seccomp_usage[] = {
40 "perf bench sched secccomp-notify <options>",
41 NULL
42};
43
44static int seccomp(unsigned int op, unsigned int flags, void *args)
45{
46 return syscall(__NR_seccomp, op, flags, args);
47}
48
49static int user_notif_syscall(int nr, unsigned int flags)
50{
51 struct sock_filter filter[] = {
52 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
53 offsetof(struct seccomp_data, nr)),
54 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, nr, 0, 1),
55 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_USER_NOTIF),
56 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
57 };
58
59 struct sock_fprog prog = {
60 .len = (unsigned short)ARRAY_SIZE(filter),
61 .filter = filter,
62 };
63
64 return seccomp(SECCOMP_SET_MODE_FILTER, flags, args: &prog);
65}
66
67#define USER_NOTIF_MAGIC INT_MAX
68static void user_notification_sync_loop(int listener)
69{
70 struct seccomp_notif_resp resp;
71 struct seccomp_notif req;
72 uint64_t nr;
73
74 for (nr = 0; nr < loops; nr++) {
75 memset(&req, 0, sizeof(req));
76 if (ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req))
77 err(EXIT_FAILURE, "SECCOMP_IOCTL_NOTIF_RECV failed");
78
79 if (req.data.nr != __NR_gettid)
80 errx(EXIT_FAILURE, "unexpected syscall: %d", req.data.nr);
81
82 resp.id = req.id;
83 resp.error = 0;
84 resp.val = USER_NOTIF_MAGIC;
85 resp.flags = 0;
86 if (ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp))
87 err(EXIT_FAILURE, "SECCOMP_IOCTL_NOTIF_SEND failed");
88 }
89}
90
91#ifndef SECCOMP_USER_NOTIF_FD_SYNC_WAKE_UP
92#define SECCOMP_USER_NOTIF_FD_SYNC_WAKE_UP (1UL << 0)
93#define SECCOMP_IOCTL_NOTIF_SET_FLAGS SECCOMP_IOW(4, __u64)
94#endif
95int bench_sched_seccomp_notify(int argc, const char **argv)
96{
97 struct timeval start, stop, diff;
98 unsigned long long result_usec = 0;
99 int status, listener;
100 pid_t pid;
101 long ret;
102
103 argc = parse_options(argc, argv, options, bench_seccomp_usage, 0);
104
105 gettimeofday(&start, NULL);
106
107 prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
108 listener = user_notif_syscall(__NR_gettid,
109 SECCOMP_FILTER_FLAG_NEW_LISTENER);
110 if (listener < 0)
111 err(EXIT_FAILURE, "can't create a notification descriptor");
112
113 pid = fork();
114 if (pid < 0)
115 err(EXIT_FAILURE, "fork");
116 if (pid == 0) {
117 if (prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0))
118 err(EXIT_FAILURE, "can't set the parent death signal");
119 while (1) {
120 ret = syscall(__NR_gettid);
121 if (ret == USER_NOTIF_MAGIC)
122 continue;
123 break;
124 }
125 _exit(1);
126 }
127
128 if (sync_mode) {
129 if (ioctl(listener, SECCOMP_IOCTL_NOTIF_SET_FLAGS,
130 SECCOMP_USER_NOTIF_FD_SYNC_WAKE_UP, 0))
131 err(EXIT_FAILURE,
132 "can't set SECCOMP_USER_NOTIF_FD_SYNC_WAKE_UP");
133 }
134 user_notification_sync_loop(listener);
135
136 kill(pid, SIGKILL);
137 if (waitpid(pid, &status, 0) != pid)
138 err(EXIT_FAILURE, "waitpid(%d) failed", pid);
139 if (!WIFSIGNALED(status) || WTERMSIG(status) != SIGKILL)
140 errx(EXIT_FAILURE, "unexpected exit code: %d", status);
141
142 gettimeofday(&stop, NULL);
143 timersub(&stop, &start, &diff);
144
145 switch (bench_format) {
146 case BENCH_FORMAT_DEFAULT:
147 printf("# Executed %" PRIu64 " system calls\n\n",
148 loops);
149
150 result_usec = diff.tv_sec * USEC_PER_SEC;
151 result_usec += diff.tv_usec;
152
153 printf(" %14s: %lu.%03lu [sec]\n\n", "Total time",
154 (unsigned long) diff.tv_sec,
155 (unsigned long) (diff.tv_usec / USEC_PER_MSEC));
156
157 printf(" %14lf usecs/op\n",
158 (double)result_usec / (double)loops);
159 printf(" %14d ops/sec\n",
160 (int)((double)loops /
161 ((double)result_usec / (double)USEC_PER_SEC)));
162 break;
163
164 case BENCH_FORMAT_SIMPLE:
165 printf("%lu.%03lu\n",
166 (unsigned long) diff.tv_sec,
167 (unsigned long) (diff.tv_usec / USEC_PER_MSEC));
168 break;
169
170 default:
171 /* reaching here is something disaster */
172 fprintf(stderr, "Unknown format:%d\n", bench_format);
173 exit(1);
174 break;
175 }
176
177 return 0;
178}
179

source code of linux/tools/perf/bench/sched-seccomp-notify.c