picnoir/Systemd
1
0
Fork 0
Code Issues Pull requests Projects Releases Wiki Activity

bus: add benchmark tool to determine the right threshold for copying vs. memfd

Browse source
This commit is contained in:
Lennart Poettering 2013-05-22 16:02:21 +02:00
parent 2927b326cc
commit 8f155917bf
7 changed files with 246 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

1
.gitignore vendored
View file

@ -84,6 +84,7 @@
/test-bus-chat
/test-bus-kernel
/test-bus-kernel-bloom
/test-bus-kernel-benchmark
/test-bus-marshal
/test-bus-match
/test-bus-memfd

12
Makefile.am
View file

@ -1764,6 +1764,7 @@ tests += \
test-bus-match \
test-bus-kernel \
test-bus-kernel-bloom \
test-bus-kernel-benchmark \
test-bus-memfd \
test-bus-zero-copy
@ -1848,6 +1849,17 @@ test_bus_kernel_bloom_LDADD = \
libsystemd-bus.la \
libsystemd-id128-internal.la
test_bus_kernel_benchmark_SOURCES = \
src/libsystemd-bus/test-bus-kernel-benchmark.c
test_bus_kernel_benchmark_CFLAGS = \
$(AM_CFLAGS)
test_bus_kernel_benchmark_LDADD = \
libsystemd-shared.la \
libsystemd-bus.la \
libsystemd-id128-internal.la
test_bus_memfd_SOURCES = \
src/libsystemd-bus/test-bus-memfd.c

2
src/libsystemd-bus/bus-internal.h
View file

@ -111,6 +111,8 @@ struct sd_bus {
bool filter_callbacks_modified:1;
bool object_callbacks_modified:1;
int use_memfd;
void *rbuffer;
size_t rbuffer_size;

2
src/libsystemd-bus/bus-kernel.c
View file

@ -326,6 +326,8 @@ int bus_kernel_take_fd(sd_bus *b) {
if (b->is_server)
return -EINVAL;
b->use_memfd = 1;
if (!b->kdbus_buffer) {
b->kdbus_buffer = mmap(NULL, KDBUS_POOL_SIZE, PROT_READ|PROT_WRITE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
if (b->kdbus_buffer == MAP_FAILED) {

6
src/libsystemd-bus/bus-message.c
View file

@ -564,7 +564,7 @@ static int message_new_reply(
goto fail;
if (call->sender) {
r = message_append_field_string(t, SD_BUS_MESSAGE_HEADER_DESTINATION, SD_BUS_TYPE_STRING, call->sender, &t->sender);
r = message_append_field_string(t, SD_BUS_MESSAGE_HEADER_DESTINATION, SD_BUS_TYPE_STRING, call->sender, &t->destination);
if (r < 0)
goto fail;
}
@ -3865,9 +3865,9 @@ int bus_message_seal(sd_bus_message *m, uint64_t serial) {
/* If this is something we can send as memfd, then let's seal
the memfd now. Note that we can send memfds as payload only
for directed messages, and not for broadcasts. */
if (m->destination) {
if (m->destination && m->bus && m->bus->use_memfd) {
MESSAGE_FOREACH_PART(part, i, m)
if (part->memfd >= 0 && !part->sealed && part->size > MEMFD_MIN_SIZE) {
if (part->memfd >= 0 && !part->sealed && (part->size > MEMFD_MIN_SIZE || m->bus->use_memfd < 0)) {
bus_body_part_unmap(part);
if (ioctl(part->memfd, KDBUS_CMD_MEMFD_SEAL_SET, 1) >= 0)

1
src/libsystemd-bus/sd-bus.c
View file

@ -2514,6 +2514,7 @@ int sd_bus_call_method(
int r;
if (!bus)
return -EINVAL;
if (!BUS_IS_OPEN(bus->state))
return -ENOTCONN;

225
src/libsystemd-bus/test-bus-kernel-benchmark.c Normal file
View file

@ -0,0 +1,225 @@
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2013 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <ctype.h>
#include <sys/wait.h>
#include "util.h"
#include "log.h"
#include "sd-bus.h"
#include "bus-message.h"
#include "bus-error.h"
#include "bus-kernel.h"
#include "bus-internal.h"
#define N_TRIES 500
#define MAX_SIZE (5*1024*1024)
static void server(sd_bus *b, usec_t *result) {
usec_t x = 0;
int r;
for (;;) {
_cleanup_bus_message_unref_ sd_bus_message *m = NULL;
r = sd_bus_process(b, &m);
assert_se(r >= 0);
if (r == 0)
assert_se(sd_bus_wait(b, (usec_t) -1) >= 0);
if (!m)
continue;
/* log_error("huhu %s from %s", sd_bus_message_get_member(m), sd_bus_message_get_sender(m)); */
if (sd_bus_message_is_method_call(m, "benchmark.server", "Work")) {
_cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
size_t i, sz;
char *q;
const char *p;
assert_se(sd_bus_message_read_array(m, 'y', (const void**) &p, &sz) > 0);
assert_se(sd_bus_message_new_method_return(b, m, &reply) >= 0);
assert_se(sd_bus_message_append_array_space(reply, 'y', sz, (void**) &q) >= 0);
x = now(CLOCK_MONOTONIC);
for (i = 0; i < sz; i++)
q[i] = toupper(p[i]);
x = now(CLOCK_MONOTONIC) - x;
assert_se(sd_bus_send(b, reply, NULL) >= 0);
} else if (sd_bus_message_is_method_call(m, "benchmark.server", "Exit")) {
usec_t t;
assert_se(sd_bus_message_read(m, "t", &t) > 0);
assert_se(t >= x);
*result = t - x;
return;
} else if (sd_bus_message_is_method_call(m, "benchmark.server", "Ping")) {
assert_se(sd_bus_reply_method_return(b, m, "y", 1) >= 0);
} else
assert_not_reached("Unknown method");
}
}
static void client(sd_bus *b, size_t sz) {
_cleanup_bus_message_unref_ sd_bus_message *m = NULL, *reply = NULL;
char *p;
const char *q;
usec_t t;
size_t l, i;
assert_se(sd_bus_call_method(b, ":1.1", "/", "benchmark.server", "Ping", NULL, NULL, NULL) >= 0);
assert_se(sd_bus_message_new_method_call(b, ":1.1", "/", "benchmark.server", "Work", &m) >= 0);
assert_se(sd_bus_message_append_array_space(m, 'y', sz, (void**) &p) >= 0);
for (i = 0; i < sz; i++)
p[i] = 'a' + (char) (i % 26);
t = now(CLOCK_MONOTONIC);
assert_se(sd_bus_send_with_reply_and_block(b, m, 0, NULL, &reply) >= 0);
t = now(CLOCK_MONOTONIC) - t;
assert_se(sd_bus_message_read_array(reply, 'y', (const void**) &q, &l) > 0);
assert_se(l == sz);
for (i = 0; i < sz; i++) {
assert_se(q[i] == 'A' + (char) (i % 26));
}
sd_bus_message_unref(m);
assert_se(sd_bus_message_new_method_call(b, ":1.1", "/", "benchmark.server", "Exit", &m) >= 0);
assert_se(sd_bus_message_append(m, "t", t) >= 0);
assert_se(sd_bus_send(b, m, NULL) >= 0);
}
static void run_benchmark(size_t sz, bool force_copy, usec_t *result) {
_cleanup_close_ int bus_ref = -1;
_cleanup_free_ char *bus_name = NULL, *address = NULL;
sd_bus *b;
int r;
pid_t pid;
bus_ref = bus_kernel_create("deine-mutter", &bus_name);
if (bus_ref == -ENOENT)
exit(EXIT_TEST_SKIP);
assert_se(bus_ref >= 0);
address = strappend("kernel:path=", bus_name);
assert_se(address);
r = sd_bus_new(&b);
assert_se(r >= 0);
b->use_memfd = force_copy ? 0 : -1;
r = sd_bus_set_address(b, address);
assert_se(r >= 0);
r = sd_bus_start(b);
assert_se(r >= 0);
pid = fork();
assert_se(pid >= 0);
if (pid == 0) {
close_nointr_nofail(bus_ref);
sd_bus_unref(b);
r = sd_bus_new(&b);
assert_se(r >= 0);
b->use_memfd = force_copy ? 0 : -1;
r = sd_bus_set_address(b, address);
assert_se(r >= 0);
r = sd_bus_start(b);
assert_se(r >= 0);
client(b, sz);
_exit(0);
}
server(b, result);
sd_bus_unref(b);
assert_se(waitpid(pid, NULL, 0) == pid);
}
int main(int argc, char *argv[]) {
size_t lsize, rsize, csize;
log_set_max_level(LOG_DEBUG);
lsize = 1;
rsize = MAX_SIZE;
for (;;) {
usec_t copy = 0, memfd = 0;
unsigned i;
csize = (lsize + rsize) / 2;
log_info("Trying size=%zu", csize);
if (csize <= lsize)
break;
for (i = 0; i < N_TRIES; i++) {
usec_t t;
run_benchmark(csize, true, &t);
copy += t;
}
for (i = 0; i < N_TRIES; i++) {
usec_t t;
run_benchmark(csize, false, &t);
memfd += t;
}
copy /= N_TRIES;
memfd /= N_TRIES;
if (copy == memfd)
break;
if (copy < memfd)
lsize = csize;
else
rsize = csize;
}
log_info("Copying/memfd are equally fast at %zu", csize);
return 0;
}