Files
linux-stable-mirror/tools/perf/bench/uprobe.c
T
Ian RogersandArnaldo Carvalho de Melo 713eeb2279 perf build: Move BPF skeleton generation out of Makefile.perf
Currently, the top-level Makefile.perf defines a massive global bpf-skel
umbrella target that pre-compiles all 12+ BPF skeletons (%.skel.h) upfront
before launching sub-makes. This forces unrelated sub-makes to serialize
behind bpftool and clang BPF target evaluations, causing parallel build
bottlenecks.

Furthermore, bench_uprobe.bpf.c lived inside util/bpf_skel/, breaking
conceptual directory encapsulation since it is consumed purely by
bench/uprobe.c.

Refactor the BPF skeletons to better achieve directory isolation:
1. Move tools/perf/util/bpf_skel/bench_uprobe.bpf.c directly into
   tools/perf/bench/bpf_skel/.
2. Extract the skeleton generation infrastructure out of Makefile.perf into
   a shared inclusion file tools/perf/bpf_skel.mak.
3. Include bpf_skel.mak locally inside tools/perf/util/Build and
   tools/perf/bench/Build and bind precise local prerequisites.
4. Safely synchronize the shared bpftool bootstrap and vmlinux.h targets
   via the conditional prepare: umbrella to avoid parallel sub-make races,
   while evaluating the actual skeletons completely locally on demand. A
   later patch will move these targets into bpf_skel.mak.
5. Export CLANG from the global Makefile to ensure accurate tool
   propagation.
6. Clean up Makefile.perf by stripping the global bpf-skel umbrella target
   and its SKELETONS list.

While removing code from Makefile.perf generally helps build
performance, the impact here is minimal. The main motivation for the
change is to better encapsulate things in the build and simplify
Makefile.perf that has around 50 lines removed.

Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Assisted-by: Gemini:gemini-3.1-pro-preview
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: James Clark <james.clark@linaro.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexandre Chartre <alexandre.chartre@oracle.com>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Ankur Arora <ankur.a.arora@oracle.com>
Cc: Collin Funk <collin.funk1@gmail.com>
Cc: Costa Shulyupin <costa.shul@redhat.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Dapeng Mi <dapeng1.mi@linux.intel.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Dmitrii Dolgov <9erthalion6@gmail.com>
Cc: Eduard Zingerman <eddyz87@gmail.com>
Cc: Howard Chu <howardchu95@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Cc: Leo Yan <leo.yan@arm.com>
Cc: Markus Mayer <mmayer@broadcom.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Terrell <terrelln@fb.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <pjw@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Monnet <qmo@kernel.org>
Cc: Ricky Ringler <ricky.ringler@proton.me>
Cc: Song Liu <song@kernel.org>
Cc: Swapnil Sapkal <swapnil.sapkal@amd.com>
Cc: Thomas Falcon <thomas.falcon@intel.com>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-05-20 17:46:45 -03:00

214 lines
5.3 KiB
C

// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
/*
* uprobe.c
*
* uprobe benchmarks
*
* Copyright (C) 2023, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
*/
#include "../perf.h"
#include "../util/util.h"
#include <subcmd/parse-options.h>
#include "../builtin.h"
#include "bench.h"
#include <linux/compiler.h>
#include <linux/time64.h>
#include <inttypes.h>
#include <stdio.h>
#include <sys/time.h>
#include <sys/types.h>
#include <time.h>
#include <unistd.h>
#include <stdlib.h>
#define LOOPS_DEFAULT 1000
static int loops = LOOPS_DEFAULT;
enum bench_uprobe {
BENCH_UPROBE__BASELINE,
BENCH_UPROBE__EMPTY,
BENCH_UPROBE__TRACE_PRINTK,
BENCH_UPROBE__EMPTY_RET,
BENCH_UPROBE__TRACE_PRINTK_RET,
};
static const struct option options[] = {
OPT_INTEGER('l', "loop", &loops, "Specify number of loops"),
OPT_END()
};
static const char * const bench_uprobe_usage[] = {
"perf bench uprobe <options>",
NULL
};
#ifdef HAVE_BPF_SKEL
#include "bench/bpf_skel/bench_uprobe.skel.h"
#define bench_uprobe__attach_uprobe(prog) \
skel->links.prog = bpf_program__attach_uprobe_opts(/*prog=*/skel->progs.prog, \
/*pid=*/-1, \
/*binary_path=*/"libc.so.6", \
/*func_offset=*/0, \
/*opts=*/&uprobe_opts); \
if (!skel->links.prog) { \
err = -errno; \
fprintf(stderr, "Failed to attach bench uprobe \"%s\": %m\n", #prog); \
goto cleanup; \
}
static struct bench_uprobe_bpf *skel;
static int bench_uprobe__setup_bpf_skel(enum bench_uprobe bench)
{
DECLARE_LIBBPF_OPTS(bpf_uprobe_opts, uprobe_opts);
int err;
/* Load and verify BPF application */
skel = bench_uprobe_bpf__open();
if (!skel) {
fprintf(stderr, "Failed to open and load uprobes bench BPF skeleton\n");
return -1;
}
err = bench_uprobe_bpf__load(skel);
if (err) {
fprintf(stderr, "Failed to load and verify BPF skeleton\n");
goto cleanup;
}
uprobe_opts.func_name = "usleep";
switch (bench) {
case BENCH_UPROBE__BASELINE: break;
case BENCH_UPROBE__EMPTY: bench_uprobe__attach_uprobe(empty); break;
case BENCH_UPROBE__TRACE_PRINTK: bench_uprobe__attach_uprobe(trace_printk); break;
case BENCH_UPROBE__EMPTY_RET: bench_uprobe__attach_uprobe(empty_ret); break;
case BENCH_UPROBE__TRACE_PRINTK_RET: bench_uprobe__attach_uprobe(trace_printk_ret); break;
default:
fprintf(stderr, "Invalid bench: %d\n", bench);
goto cleanup;
}
return err;
cleanup:
bench_uprobe_bpf__destroy(skel);
skel = NULL;
return err;
}
static void bench_uprobe__teardown_bpf_skel(void)
{
if (skel) {
bench_uprobe_bpf__destroy(skel);
skel = NULL;
}
}
#else
static int bench_uprobe__setup_bpf_skel(enum bench_uprobe bench __maybe_unused) { return 0; }
static void bench_uprobe__teardown_bpf_skel(void) {};
#endif
static int bench_uprobe_format__default_fprintf(const char *name, const char *unit, u64 diff, FILE *fp)
{
static u64 baseline, previous;
s64 diff_to_baseline = diff - baseline,
diff_to_previous = diff - previous;
int printed = fprintf(fp, "# Executed %'d %s calls\n", loops, name);
printed += fprintf(fp, " %14s: %'" PRIu64 " %ss", "Total time", diff, unit);
if (baseline) {
printed += fprintf(fp, " %s%'" PRId64 " to baseline", diff_to_baseline > 0 ? "+" : "", diff_to_baseline);
if (previous != baseline)
fprintf(stdout, " %s%'" PRId64 " to previous", diff_to_previous > 0 ? "+" : "", diff_to_previous);
}
printed += fprintf(fp, "\n\n %'.3f %ss/op", (double)diff / (double)loops, unit);
if (baseline) {
printed += fprintf(fp, " %'.3f %ss/op to baseline", (double)diff_to_baseline / (double)loops, unit);
if (previous != baseline)
printed += fprintf(fp, " %'.3f %ss/op to previous", (double)diff_to_previous / (double)loops, unit);
} else {
baseline = diff;
}
fputc('\n', fp);
previous = diff;
return printed + 1;
}
static int bench_uprobe(int argc, const char **argv, enum bench_uprobe bench)
{
const char *name = "usleep(1000)", *unit = "usec";
struct timespec start, end;
u64 diff;
int i;
argc = parse_options(argc, argv, options, bench_uprobe_usage, 0);
if (bench != BENCH_UPROBE__BASELINE && bench_uprobe__setup_bpf_skel(bench) < 0)
return 0;
clock_gettime(CLOCK_REALTIME, &start);
for (i = 0; i < loops; i++) {
usleep(USEC_PER_MSEC);
}
clock_gettime(CLOCK_REALTIME, &end);
diff = end.tv_sec * NSEC_PER_SEC + end.tv_nsec - (start.tv_sec * NSEC_PER_SEC + start.tv_nsec);
diff /= NSEC_PER_USEC;
switch (bench_format) {
case BENCH_FORMAT_DEFAULT:
bench_uprobe_format__default_fprintf(name, unit, diff, stdout);
break;
case BENCH_FORMAT_SIMPLE:
printf("%" PRIu64 "\n", diff);
break;
default:
/* reaching here is something of a disaster */
fprintf(stderr, "Unknown format:%d\n", bench_format);
exit(1);
}
if (bench != BENCH_UPROBE__BASELINE)
bench_uprobe__teardown_bpf_skel();
return 0;
}
int bench_uprobe_baseline(int argc, const char **argv)
{
return bench_uprobe(argc, argv, BENCH_UPROBE__BASELINE);
}
int bench_uprobe_empty(int argc, const char **argv)
{
return bench_uprobe(argc, argv, BENCH_UPROBE__EMPTY);
}
int bench_uprobe_trace_printk(int argc, const char **argv)
{
return bench_uprobe(argc, argv, BENCH_UPROBE__TRACE_PRINTK);
}
int bench_uprobe_empty_ret(int argc, const char **argv)
{
return bench_uprobe(argc, argv, BENCH_UPROBE__EMPTY_RET);
}
int bench_uprobe_trace_printk_ret(int argc, const char **argv)
{
return bench_uprobe(argc, argv, BENCH_UPROBE__TRACE_PRINTK_RET);
}