xref: /openbmc/linux/tools/perf/bench/uprobe.c (revision 18afb028)
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 	return err;
93 }
94 
95 static void bench_uprobe__teardown_bpf_skel(void)
96 {
97 	if (skel) {
98 		bench_uprobe_bpf__destroy(skel);
99 		skel = NULL;
100 	}
101 }
102 #else
103 static int bench_uprobe__setup_bpf_skel(enum bench_uprobe bench __maybe_unused) { return 0; }
104 static void bench_uprobe__teardown_bpf_skel(void) {};
105 #endif
106 
107 static int bench_uprobe_format__default_fprintf(const char *name, const char *unit, u64 diff, FILE *fp)
108 {
109 	static u64 baseline, previous;
110 	s64 diff_to_baseline = diff - baseline,
111 	    diff_to_previous = diff - previous;
112 	int printed = fprintf(fp, "# Executed %'d %s calls\n", loops, name);
113 
114 	printed += fprintf(fp, " %14s: %'" PRIu64 " %ss", "Total time", diff, unit);
115 
116 	if (baseline) {
117 		printed += fprintf(fp, " %s%'" PRId64 " to baseline", diff_to_baseline > 0 ? "+" : "", diff_to_baseline);
118 
119 		if (previous != baseline)
120 			fprintf(stdout, " %s%'" PRId64 " to previous", diff_to_previous > 0 ? "+" : "", diff_to_previous);
121 	}
122 
123 	printed += fprintf(fp, "\n\n %'.3f %ss/op", (double)diff / (double)loops, unit);
124 
125 	if (baseline) {
126 		printed += fprintf(fp, " %'.3f %ss/op to baseline", (double)diff_to_baseline / (double)loops, unit);
127 
128 		if (previous != baseline)
129 			printed += fprintf(fp, " %'.3f %ss/op to previous", (double)diff_to_previous / (double)loops, unit);
130 	} else {
131 		baseline = diff;
132 	}
133 
134 	fputc('\n', fp);
135 
136 	previous = diff;
137 
138 	return printed + 1;
139 }
140 
141 static int bench_uprobe(int argc, const char **argv, enum bench_uprobe bench)
142 {
143 	const char *name = "usleep(1000)", *unit = "usec";
144 	struct timespec start, end;
145 	u64 diff;
146 	int i;
147 
148 	argc = parse_options(argc, argv, options, bench_uprobe_usage, 0);
149 
150 	if (bench != BENCH_UPROBE__BASELINE && bench_uprobe__setup_bpf_skel(bench) < 0)
151 		return 0;
152 
153         clock_gettime(CLOCK_REALTIME, &start);
154 
155 	for (i = 0; i < loops; i++) {
156 		usleep(USEC_PER_MSEC);
157 	}
158 
159 	clock_gettime(CLOCK_REALTIME, &end);
160 
161 	diff = end.tv_sec * NSEC_PER_SEC + end.tv_nsec - (start.tv_sec * NSEC_PER_SEC + start.tv_nsec);
162 	diff /= NSEC_PER_USEC;
163 
164 	switch (bench_format) {
165 	case BENCH_FORMAT_DEFAULT:
166 		bench_uprobe_format__default_fprintf(name, unit, diff, stdout);
167 		break;
168 
169 	case BENCH_FORMAT_SIMPLE:
170 		printf("%" PRIu64 "\n", diff);
171 		break;
172 
173 	default:
174 		/* reaching here is something of a disaster */
175 		fprintf(stderr, "Unknown format:%d\n", bench_format);
176 		exit(1);
177 	}
178 
179 	if (bench != BENCH_UPROBE__BASELINE)
180 		bench_uprobe__teardown_bpf_skel();
181 
182 	return 0;
183 }
184 
185 int bench_uprobe_baseline(int argc, const char **argv)
186 {
187 	return bench_uprobe(argc, argv, BENCH_UPROBE__BASELINE);
188 }
189 
190 int bench_uprobe_empty(int argc, const char **argv)
191 {
192 	return bench_uprobe(argc, argv, BENCH_UPROBE__EMPTY);
193 }
194 
195 int bench_uprobe_trace_printk(int argc, const char **argv)
196 {
197 	return bench_uprobe(argc, argv, BENCH_UPROBE__TRACE_PRINTK);
198 }
199