summaryrefslogtreecommitdiffstats
path: root/tools/perf/bench/sched-seccomp-notify.c
blob: 269c1f4a6852ce49584674322943f1b71e9a77cd (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
// SPDX-License-Identifier: GPL-2.0
#include <subcmd/parse-options.h>
#include "bench.h"

#include <uapi/linux/filter.h>
#include <sys/types.h>
#include <sys/time.h>
#include <linux/unistd.h>
#include <sys/syscall.h>
#include <sys/ioctl.h>
#include <linux/time64.h>
#include <uapi/linux/seccomp.h>
#include <sys/prctl.h>

#include <unistd.h>
#include <limits.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <sys/wait.h>
#include <string.h>
#include <errno.h>
#include <err.h>
#include <inttypes.h>

#define LOOPS_DEFAULT 1000000UL
static uint64_t loops = LOOPS_DEFAULT;
static bool sync_mode;

static const struct option options[] = {
	OPT_U64('l', "loop",	&loops,		"Specify number of loops"),
	OPT_BOOLEAN('s', "sync-mode", &sync_mode,
		    "Enable the synchronous mode for seccomp notifications"),
	OPT_END()
};

static const char * const bench_seccomp_usage[] = {
	"perf bench sched secccomp-notify <options>",
	NULL
};

static int seccomp(unsigned int op, unsigned int flags, void *args)
{
	return syscall(__NR_seccomp, op, flags, args);
}

static int user_notif_syscall(int nr, unsigned int flags)
{
	struct sock_filter filter[] = {
		BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
			offsetof(struct seccomp_data, nr)),
		BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, nr, 0, 1),
		BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_USER_NOTIF),
		BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
	};

	struct sock_fprog prog = {
		.len = (unsigned short)ARRAY_SIZE(filter),
		.filter = filter,
	};

	return seccomp(SECCOMP_SET_MODE_FILTER, flags, &prog);
}

#define USER_NOTIF_MAGIC INT_MAX
static void user_notification_sync_loop(int listener)
{
	struct seccomp_notif_resp resp;
	struct seccomp_notif req;
	uint64_t nr;

	for (nr = 0; nr < loops; nr++) {
		memset(&req, 0, sizeof(req));
		if (ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req))
			err(EXIT_FAILURE, "SECCOMP_IOCTL_NOTIF_RECV failed");

		if (req.data.nr != __NR_gettid)
			errx(EXIT_FAILURE, "unexpected syscall: %d", req.data.nr);

		resp.id = req.id;
		resp.error = 0;
		resp.val = USER_NOTIF_MAGIC;
		resp.flags = 0;
		if (ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp))
			err(EXIT_FAILURE, "SECCOMP_IOCTL_NOTIF_SEND failed");
	}
}

#ifndef SECCOMP_USER_NOTIF_FD_SYNC_WAKE_UP
#define SECCOMP_USER_NOTIF_FD_SYNC_WAKE_UP (1UL << 0)
#define SECCOMP_IOCTL_NOTIF_SET_FLAGS  SECCOMP_IOW(4, __u64)
#endif
int bench_sched_seccomp_notify(int argc, const char **argv)
{
	struct timeval start, stop, diff;
	unsigned long long result_usec = 0;
	int status, listener;
	pid_t pid;
	long ret;

	argc = parse_options(argc, argv, options, bench_seccomp_usage, 0);

	gettimeofday(&start, NULL);

	prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
	listener = user_notif_syscall(__NR_gettid,
				      SECCOMP_FILTER_FLAG_NEW_LISTENER);
	if (listener < 0)
		err(EXIT_FAILURE, "can't create a notification descriptor");

	pid = fork();
	if (pid < 0)
		err(EXIT_FAILURE, "fork");
	if (pid == 0) {
		if (prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0))
			err(EXIT_FAILURE, "can't set the parent death signal");
		while (1) {
			ret = syscall(__NR_gettid);
			if (ret == USER_NOTIF_MAGIC)
				continue;
			break;
		}
		_exit(1);
	}

	if (sync_mode) {
		if (ioctl(listener, SECCOMP_IOCTL_NOTIF_SET_FLAGS,
			     SECCOMP_USER_NOTIF_FD_SYNC_WAKE_UP, 0))
			err(EXIT_FAILURE,
			    "can't set SECCOMP_USER_NOTIF_FD_SYNC_WAKE_UP");
	}
	user_notification_sync_loop(listener);

	kill(pid, SIGKILL);
	if (waitpid(pid, &status, 0) != pid)
		err(EXIT_FAILURE, "waitpid(%d) failed", pid);
	if (!WIFSIGNALED(status) || WTERMSIG(status) != SIGKILL)
		errx(EXIT_FAILURE, "unexpected exit code: %d", status);

	gettimeofday(&stop, NULL);
	timersub(&stop, &start, &diff);

	switch (bench_format) {
	case BENCH_FORMAT_DEFAULT:
		printf("# Executed %" PRIu64 " system calls\n\n",
			loops);

		result_usec = diff.tv_sec * USEC_PER_SEC;
		result_usec += diff.tv_usec;

		printf(" %14s: %lu.%03lu [sec]\n\n", "Total time",
		       (unsigned long) diff.tv_sec,
		       (unsigned long) (diff.tv_usec / USEC_PER_MSEC));

		printf(" %14lf usecs/op\n",
		       (double)result_usec / (double)loops);
		printf(" %14d ops/sec\n",
		       (int)((double)loops /
			     ((double)result_usec / (double)USEC_PER_SEC)));
		break;

	case BENCH_FORMAT_SIMPLE:
		printf("%lu.%03lu\n",
		       (unsigned long) diff.tv_sec,
		       (unsigned long) (diff.tv_usec / USEC_PER_MSEC));
		break;

	default:
		/* reaching here is something disaster */
		fprintf(stderr, "Unknown format:%d\n", bench_format);
		exit(1);
		break;
	}

	return 0;
}