// SPDX-License-Identifier: GPL-2.0
#include <stdlib.h>
#include <stddef.h>
#include <ftw.h>
#include <fcntl.h>
#include <errno.h>
#include <unistd.h>
#include <pthread.h>
#include <sys/mman.h>
#include <sys/wait.h>
#include <linux/kernel.h>
#include <linux/time64.h>
#include <linux/list.h>
#include <linux/err.h>
#include <linux/zalloc.h>
#include <internal/lib.h>
#include <subcmd/parse-options.h>
#include "bench.h"
#include "util/data.h"
#include "util/stat.h"
#include "util/debug.h"
#include "util/symbol.h"
#include "util/session.h"
#include "util/build-id.h"
#include "util/sample.h"
#include "util/synthetic-events.h"
#define MMAP_DEV_MAJOR 8
#define DSO_MMAP_RATIO 4
static unsigned int iterations = 100;
static unsigned int nr_mmaps = 100;
static unsigned int nr_samples = 100; /* samples per mmap */
static u64 bench_sample_type;
static u16 bench_id_hdr_size;
struct bench_data {
int pid;
int input_pipe[2];
int output_pipe[2];
pthread_t th;
};
struct bench_dso {
struct list_head list;
char *name;
int ino;
};
static int nr_dsos;
static struct bench_dso *dsos;
extern int cmd_inject(int argc, const char *argv[]);
static const struct option options[] = {
OPT_UINTEGER('i', "iterations", &iterations,
"Number of iterations used to compute average (default: 100)"),
OPT_UINTEGER('m', "nr-mmaps", &nr_mmaps,
"Number of mmap events for each iteration (default: 100)"),
OPT_UINTEGER('n', "nr-samples", &nr_samples,
"Number of sample events per mmap event (default: 100)"),
OPT_INCR('v', "verbose", &verbose,
"be more verbose (show iteration count, DSO name, etc)"),
OPT_END()
};
static const char *const bench_usage[] = {
"perf bench internals inject-build-id <options>",
NULL
};
/*
* Helper for collect_dso that adds the given file as a dso to dso_list
* if it contains a build-id. Stops after collecting 4 times more than
* we need (for MMAP2 events).
*/
static int add_dso(const char *fpath, const struct stat *sb __maybe_unused,
int typeflag, struct FTW *ftwbuf __maybe_unused)
{
struct bench_dso *dso = &dsos[nr_dsos];
struct build_id bid;
if (typeflag == FTW_D || typeflag == FTW_SL)
return 0;
if (filename__read_build_id(fpath, &bid) < 0)
return 0;
dso->name = realpath(fpath, NULL);
if (dso->name == NULL)
return -1;
dso->ino = nr_dsos++;
pr_debug2(" Adding DSO: %s\n", fpath);
/* stop if we collected enough DSOs */
if ((unsigned int)nr_dsos == DSO_MMAP_RATIO * nr_mmaps)
return 1;
return 0;
}
static void collect_dso(void)
{
dsos = calloc(nr_mmaps * DSO_MMAP_RATIO, sizeof(*dsos));
if (dsos == NULL) {
printf(" Memory allocation failed\n");
exit(1);
}
if (nftw("/usr/lib/", add_dso, 10, FTW_PHYS) < 0)
return;
pr_debug(" Collected %d DSOs\n", nr_dsos);
}
static void release_dso(void)
{
int i;
for (i = 0; i < nr_dsos; i++) {
struct bench_dso *dso = &dsos[i];
zfree(&dso->name);
}
free(dsos);
}
/* Fake address used by mmap and sample events */
static u64 dso_map_addr(struct bench_dso *dso)
{
return 0x400000ULL + dso->ino * 8192ULL;
}
static ssize_t synthesize_attr(struct bench_data *data)
{
union perf_event event;
memset(&event, 0, sizeof(event.attr) + sizeof(u64));
event.header.type = PERF_RECORD_HEADER_ATTR;
event.header.size = sizeof(event.attr) + sizeof(u64);
event.attr.attr.type = PERF_TYPE_SOFTWARE;
event.attr.attr.config = PERF_COUNT_SW_TASK_CLOCK;
event.attr.attr.exclude_kernel = 1;
event.attr.attr.sample_id_all = 1;
event.attr.attr.sample_type = bench_sample_type;
return writen(data->input_pipe[1], &event, event.header.size);
}
static ssize_t synthesize_fork(struct bench_data *data)
{
union perf_event event;
memset(&event, 0, sizeof(event.fork) + bench_id_hdr_size);
event.header.type = PERF_RECORD_FORK;
event.header.misc = PERF_RECORD_MISC_FORK_EXEC;
event.header.size = sizeof(event.fork) + bench_id_hdr_size;
event.fork.ppid = 1;
event.fork.ptid = 1;
event.fork.pid = data->pid;
event.fork.tid = data->pid;
return writen(data->input_pipe[1], &event, event.header.size);
}
static ssize_t synthesize_mmap(struct bench_data *data, struct bench_dso *dso, u64 timestamp)
{
union perf_event event;
size_t len = offsetof(struct perf_record_mmap2, filename);
u64 *id_hdr_ptr = (void *)&event;
int ts_idx;
len += roundup(strlen(dso->name) + 1, 8) + bench_id_hdr_size;
memset(&event, 0, min(len, sizeof(event.mmap2)));
event.header.type = PERF_RECORD_MMAP2;
event.header.misc = PERF_RECORD_MISC_USER;
event.header.size = len;
event.mmap2.pid = data->pid;
event.mmap2.tid = data->pid;
event.mmap2.maj = MMAP_DEV_MAJOR;
event.mmap2.ino = dso->ino;
strcpy(event.mmap2.filename, dso->name);
event.mmap2.start = dso_map_addr(dso);
event.mmap2.len = 4096;
event.mmap2.prot = PROT_EXEC;
if (len > sizeof(event.mmap2)) {
/* write mmap2 event first */
if (writen(data->input_pipe[1], &event, len - bench_id_hdr_size) < 0)
return -1;
/* zero-fill sample id header */
memset(id_hdr_ptr, 0, bench_id_hdr_size);
/* put timestamp in the right position */
ts_idx = (bench_id_hdr_size / sizeof(u64)) - 2;
id_hdr_ptr[ts_idx] = timestamp;
if (writen(data->input_pipe[1], id_hdr_ptr, bench_id_hdr_size) < 0)
return -1;
return len;
}
ts_idx = (len / sizeof(u64)) - 2;
id_hdr_ptr[ts_idx] = timestamp;
return writen(data->input_pipe[1], &event, len);
}
static ssize_t synthesize_sample(struct bench_data *data, struct bench_dso *dso, u64 timestamp)
{
union perf_event event;
struct perf_sample sample = {
.tid = data->pid,
.pid = data->pid,
.ip = dso_map_addr(dso),
.time = timestamp,
};
event.header.type = PERF_RECORD_SAMPLE;
event.header.misc = PERF_RECORD_MISC_USER;
event.header.size = perf_event__sample_event_size(&sample, bench_sample_type, 0);
perf_event__synthesize_sample(&event, bench_sample_type, 0, &sample);
return writen(data->input_pipe[1], &event, event.header.size);
}
static ssize_t synthesize_flush(struct bench_data *data)
{
struct perf_event_header header = {
.size = sizeof(header),
.type = PERF_RECORD_FINISHED_ROUND,
};
return writen(data->input_pipe[1], &header, header.size);
}
static void *data_reader(void *arg)
{
struct bench_data *data = arg;
char buf[8192];
int flag;
int n;
flag = fcntl(data->output_pipe[0], F_GETFL);
fcntl(data->output_pipe[0], F_SETFL, flag | O_NONBLOCK);
/* read out data from child */
while (true) {
n = read(data->output_pipe[0], buf, sizeof(buf));
if (n > 0)
continue;
if (n == 0)
break;
if (errno != EINTR && errno != EAGAIN)
break;
usleep(100);
}
close(data->output_pipe[0]);
return NULL;
}
static int setup_injection(struct bench_data *data, bool build_id_all)
{
int ready_pipe[2];
int dev_null_fd;
char buf;
if (pipe(ready_pipe) < 0)
return -1;
if (pipe(data->input_pipe) < 0)
return -1;
if (pipe(data->output_pipe) < 0)
return -1;
data->pid = fork();
if (data->pid < 0)
return -1;
if (data->pid == 0) {
const char **inject_argv;
int inject_argc = 2;
close(data->input_pipe[1]);
close(data->output_pipe[0]);
close(ready_pipe[0]);
dup2(data->input_pipe[0], STDIN_FILENO);
close(data->input_pipe[0]);
dup2(data->output_pipe[1], STDOUT_FILENO);
close(data->output_pipe[1]);
dev_null_fd = open("/dev/null", O_WRONLY);
if (dev_null_fd < 0)
exit(1);
dup2(dev_null_fd, STDERR_FILENO);
if (build_id_all)
inject_argc++;
inject_argv = calloc(inject_argc + 1, sizeof(*inject_argv));
if (inject_argv == NULL)
exit(1);
inject_argv[0] = strdup("inject");
inject_argv[1] = strdup("-b");
if (build_id_all)
inject_argv[2] = strdup("--buildid-all");
/* signal that we're ready to go */
close(ready_pipe[1]);
cmd_inject(inject_argc, inject_argv);
exit(0);
}
pthread_create(&data->th, NULL, data_reader, data);
close(ready_pipe[1]);
close(data->input_pipe[0]);
close(data->output_pipe[1]);
/* wait for child ready */
if (read(ready_pipe[0], &buf, 1) < 0)
return -1;
close(ready_pipe[0]);
return 0;
}
static int inject_build_id(struct bench_data *data, u64 *max_rss)
{
int status;
unsigned int i, k;
struct rusage rusage;
/* this makes the child to run */
if (perf_header__write_pipe(data->input_pipe[1]) < 0)
return -1;
if (synthesize_attr(data) < 0)
return -1;
if (synthesize_fork(data) < 0)
return -1;
for (i = 0; i < nr_mmaps; i++) {
int idx = rand() % nr_dsos;
struct bench_dso *dso = &dsos[idx];
u64 timestamp = rand() % 1000000;
pr_debug2(" [%d] injecting: %s\n", i+1, dso->name);
if (synthesize_mmap(data, dso, timestamp) < 0)
return -1;
for (k = 0; k < nr_samples; k++) {
if (synthesize_sample(data, dso, timestamp + k * 1000) < 0)
return -1;
}
if ((i + 1) % 10 == 0) {
if (synthesize_flush(data) < 0)
return -1;
}
}
/* this makes the child to finish */
close(data->input_pipe[1]);
wait4(data->pid, &status, 0, &rusage);
*max_rss = rusage.ru_maxrss;
pr_debug(" Child %d exited with %d\n", data->pid, status);
return 0;
}
static void do_inject_loop(struct bench_data *data, bool build_id_all)
{
unsigned int i;
struct stats time_stats, mem_stats;
double time_average, time_stddev;
double mem_average, mem_stddev;
init_stats(&time_stats);
init_stats(&mem_stats);
pr_debug(" Build-id%s injection benchmark\n", build_id_all ? "-all" : "");
for (i = 0; i < iterations; i++) {
struct timeval start, end, diff;
u64 runtime_us, max_rss;
pr_debug(" Iteration #%d\n", i+1);
if (setup_injection(data, build_id_all) < 0) {
printf(" Build-id injection setup failed\n");
break;
}
gettimeofday(&start, NULL);
if (inject_build_id(data, &max_rss) < 0) {
printf(" Build-id injection failed\n");
break;
}
gettimeofday(&end, NULL);
timersub(&end, &start, &diff);
runtime_us = diff.tv_sec * USEC_PER_SEC + diff.tv_usec;
update_stats(&time_stats, runtime_us);
update_stats(&mem_stats, max_rss);
pthread_join(data->th, NULL);
}
time_average = avg_stats(&time_stats) / USEC_PER_MSEC;
time_stddev = stddev_stats(&time_stats) / USEC_PER_MSEC;
printf(" Average build-id%s injection took: %.3f msec (+- %.3f msec)\n",
build_id_all ? "-all" : "", time_average, time_stddev);
/* each iteration, it processes MMAP2 + BUILD_ID + nr_samples * SAMPLE */
time_average = avg_stats(&time_stats) / (nr_mmaps * (nr_samples + 2));
time_stddev = stddev_stats(&time_stats) / (nr_mmaps * (nr_samples + 2));
printf(" Average time per event: %.3f usec (+- %.3f usec)\n",
time_average, time_stddev);
mem_average = avg_stats(&mem_stats);
mem_stddev = stddev_stats(&mem_stats);
printf(" Average memory usage: %.0f KB (+- %.0f KB)\n",
mem_average, mem_stddev);
}
static int do_inject_loops(struct bench_data *data)
{
srand(time(NULL));
symbol__init(NULL);
bench_sample_type = PERF_SAMPLE_IDENTIFIER | PERF_SAMPLE_IP;
bench_sample_type |= PERF_SAMPLE_TID | PERF_SAMPLE_TIME;
bench_id_hdr_size = 32;
collect_dso();
if (nr_dsos == 0) {
printf(" Cannot collect DSOs for injection\n");
return -1;
}
do_inject_loop(data, false);
do_inject_loop(data, true);
release_dso();
return 0;
}
int bench_inject_build_id(int argc, const char **argv)
{
struct bench_data data;
argc = parse_options(argc, argv, options, bench_usage, 0);
if (argc) {
usage_with_options(bench_usage, options);
exit(EXIT_FAILURE);
}
return do_inject_loops(&data);
}
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