xref: /linux/tools/perf/bench/uprobe.c (revision 45d8b572fac3aa8b49d53c946b3685eaf78a2824)
1 // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2 /*
3  * uprobe.c
4  *
5  * uprobe benchmarks
6  *
7  *  Copyright (C) 2023, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
8  */
9 #include "../perf.h"
10 #include "../util/util.h"
11 #include <subcmd/parse-options.h>
12 #include "../builtin.h"
13 #include "bench.h"
14 #include <linux/compiler.h>
15 #include <linux/time64.h>
16 
17 #include <inttypes.h>
18 #include <stdio.h>
19 #include <sys/time.h>
20 #include <sys/types.h>
21 #include <time.h>
22 #include <unistd.h>
23 #include <stdlib.h>
24 
25 #define LOOPS_DEFAULT 1000
26 static int loops = LOOPS_DEFAULT;
27 
28 enum bench_uprobe {
29         BENCH_UPROBE__BASELINE,
30         BENCH_UPROBE__EMPTY,
31         BENCH_UPROBE__TRACE_PRINTK,
32 };
33 
34 static const struct option options[] = {
35 	OPT_INTEGER('l', "loop",	&loops,		"Specify number of loops"),
36 	OPT_END()
37 };
38 
39 static const char * const bench_uprobe_usage[] = {
40 	"perf bench uprobe <options>",
41 	NULL
42 };
43 
44 #ifdef HAVE_BPF_SKEL
45 #include "bpf_skel/bench_uprobe.skel.h"
46 
47 #define bench_uprobe__attach_uprobe(prog) \
48 	skel->links.prog = bpf_program__attach_uprobe_opts(/*prog=*/skel->progs.prog, \
49 							   /*pid=*/-1, \
50 							   /*binary_path=*/"/lib64/libc.so.6", \
51 							   /*func_offset=*/0, \
52 							   /*opts=*/&uprobe_opts); \
53 	if (!skel->links.prog) { \
54 		err = -errno; \
55 		fprintf(stderr, "Failed to attach bench uprobe \"%s\": %s\n", #prog, strerror(errno)); \
56 		goto cleanup; \
57 	}
58 
59 struct bench_uprobe_bpf *skel;
60 
61 static int bench_uprobe__setup_bpf_skel(enum bench_uprobe bench)
62 {
63 	DECLARE_LIBBPF_OPTS(bpf_uprobe_opts, uprobe_opts);
64 	int err;
65 
66 	/* Load and verify BPF application */
67 	skel = bench_uprobe_bpf__open();
68 	if (!skel) {
69 		fprintf(stderr, "Failed to open and load uprobes bench BPF skeleton\n");
70 		return -1;
71 	}
72 
73 	err = bench_uprobe_bpf__load(skel);
74 	if (err) {
75 		fprintf(stderr, "Failed to load and verify BPF skeleton\n");
76 		goto cleanup;
77 	}
78 
79 	uprobe_opts.func_name = "usleep";
80 	switch (bench) {
81 	case BENCH_UPROBE__BASELINE:							break;
82 	case BENCH_UPROBE__EMPTY:	 bench_uprobe__attach_uprobe(empty);		break;
83 	case BENCH_UPROBE__TRACE_PRINTK: bench_uprobe__attach_uprobe(trace_printk);	break;
84 	default:
85 		fprintf(stderr, "Invalid bench: %d\n", bench);
86 		goto cleanup;
87 	}
88 
89 	return err;
90 cleanup:
91 	bench_uprobe_bpf__destroy(skel);
92 	skel = NULL;
93 	return err;
94 }
95 
96 static void bench_uprobe__teardown_bpf_skel(void)
97 {
98 	if (skel) {
99 		bench_uprobe_bpf__destroy(skel);
100 		skel = NULL;
101 	}
102 }
103 #else
104 static int bench_uprobe__setup_bpf_skel(enum bench_uprobe bench __maybe_unused) { return 0; }
105 static void bench_uprobe__teardown_bpf_skel(void) {};
106 #endif
107 
108 static int bench_uprobe_format__default_fprintf(const char *name, const char *unit, u64 diff, FILE *fp)
109 {
110 	static u64 baseline, previous;
111 	s64 diff_to_baseline = diff - baseline,
112 	    diff_to_previous = diff - previous;
113 	int printed = fprintf(fp, "# Executed %'d %s calls\n", loops, name);
114 
115 	printed += fprintf(fp, " %14s: %'" PRIu64 " %ss", "Total time", diff, unit);
116 
117 	if (baseline) {
118 		printed += fprintf(fp, " %s%'" PRId64 " to baseline", diff_to_baseline > 0 ? "+" : "", diff_to_baseline);
119 
120 		if (previous != baseline)
121 			fprintf(stdout, " %s%'" PRId64 " to previous", diff_to_previous > 0 ? "+" : "", diff_to_previous);
122 	}
123 
124 	printed += fprintf(fp, "\n\n %'.3f %ss/op", (double)diff / (double)loops, unit);
125 
126 	if (baseline) {
127 		printed += fprintf(fp, " %'.3f %ss/op to baseline", (double)diff_to_baseline / (double)loops, unit);
128 
129 		if (previous != baseline)
130 			printed += fprintf(fp, " %'.3f %ss/op to previous", (double)diff_to_previous / (double)loops, unit);
131 	} else {
132 		baseline = diff;
133 	}
134 
135 	fputc('\n', fp);
136 
137 	previous = diff;
138 
139 	return printed + 1;
140 }
141 
142 static int bench_uprobe(int argc, const char **argv, enum bench_uprobe bench)
143 {
144 	const char *name = "usleep(1000)", *unit = "usec";
145 	struct timespec start, end;
146 	u64 diff;
147 	int i;
148 
149 	argc = parse_options(argc, argv, options, bench_uprobe_usage, 0);
150 
151 	if (bench != BENCH_UPROBE__BASELINE && bench_uprobe__setup_bpf_skel(bench) < 0)
152 		return 0;
153 
154         clock_gettime(CLOCK_REALTIME, &start);
155 
156 	for (i = 0; i < loops; i++) {
157 		usleep(USEC_PER_MSEC);
158 	}
159 
160 	clock_gettime(CLOCK_REALTIME, &end);
161 
162 	diff = end.tv_sec * NSEC_PER_SEC + end.tv_nsec - (start.tv_sec * NSEC_PER_SEC + start.tv_nsec);
163 	diff /= NSEC_PER_USEC;
164 
165 	switch (bench_format) {
166 	case BENCH_FORMAT_DEFAULT:
167 		bench_uprobe_format__default_fprintf(name, unit, diff, stdout);
168 		break;
169 
170 	case BENCH_FORMAT_SIMPLE:
171 		printf("%" PRIu64 "\n", diff);
172 		break;
173 
174 	default:
175 		/* reaching here is something of a disaster */
176 		fprintf(stderr, "Unknown format:%d\n", bench_format);
177 		exit(1);
178 	}
179 
180 	if (bench != BENCH_UPROBE__BASELINE)
181 		bench_uprobe__teardown_bpf_skel();
182 
183 	return 0;
184 }
185 
186 int bench_uprobe_baseline(int argc, const char **argv)
187 {
188 	return bench_uprobe(argc, argv, BENCH_UPROBE__BASELINE);
189 }
190 
191 int bench_uprobe_empty(int argc, const char **argv)
192 {
193 	return bench_uprobe(argc, argv, BENCH_UPROBE__EMPTY);
194 }
195 
196 int bench_uprobe_trace_printk(int argc, const char **argv)
197 {
198 	return bench_uprobe(argc, argv, BENCH_UPROBE__TRACE_PRINTK);
199 }
200