libvirt/tests/vircgroupmock.c
Pavel Hrdina 76ff847386 vircgroupmock: fix cgroup v1 mocking
The `legacy` mode is also valid so we need to take it into account as
well.

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2022-10-19 16:32:14 +02:00

600 lines
18 KiB
C

/*
* Copyright (C) 2013 Red Hat, Inc.
*
* This library 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.
*
* This library 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 this library. If not, see
* <http://www.gnu.org/licenses/>.
*/
#include <config.h>
#ifdef __linux__
# include "virmock.h"
# include <unistd.h>
# include <fcntl.h>
# include <sys/stat.h>
# include <sys/sysmacros.h>
# include <stdarg.h>
# include "testutilslxc.h"
# include "viralloc.h"
# include "vircgroupv2devices.h"
static int (*real_open)(const char *path, int flags, ...);
static FILE *(*real_fopen)(const char *path, const char *mode);
static int (*real_access)(const char *path, int mode);
static int (*real_mkdir)(const char *path, mode_t mode);
static char *fakerootdir;
static char *fakesysfscgroupdir;
static const char *fakedevicedir0 = FAKEDEVDIR0;
static const char *fakedevicedir1 = FAKEDEVDIR1;
# define SYSFS_CGROUP_PREFIX "/not/really/sys/fs/cgroup"
# define SYSFS_CPU_PRESENT "/sys/devices/system/cpu/present"
# define SYSFS_CPU_PRESENT_MOCKED "devices_system_cpu_present"
/*
* The plan:
*
* We fake out /proc/mounts, so make it look as is cgroups
* are mounted on /not/really/sys/fs/cgroup. We don't
* use /sys/fs/cgroup, because we want to make it easy to
* detect places where we've not mocked enough syscalls.
*
* In any open/access/mkdir calls we look at path and if
* it starts with /not/really/sys/fs/cgroup, we rewrite
* the path to point at a subdirectory of the temporary
* directory referred to by LIBVIRT_FAKE_ROOT_DIR env
* variable that is set by the main test suite
*
* In mkdir() calls, we simulate the cgroups behaviour
* whereby creating the directory auto-creates a bunch
* of files beneath it
*/
static int make_file(const char *path,
const char *name,
const char *value)
{
int fd = -1;
int ret = -1;
char *filepath = NULL;
if (asprintf(&filepath, "%s/%s", path, name) < 0)
return -1;
if ((fd = real_open(filepath, O_CREAT|O_WRONLY, 0600)) < 0)
goto cleanup;
if (write(fd, value, strlen(value)) != strlen(value)) /* sc_avoid_write */
goto cleanup;
ret = 0;
cleanup:
if (fd != -1 && close(fd) < 0)
ret = -1;
free(filepath);
return ret;
}
static int make_controller_v1(const char *path, mode_t mode)
{
const char *controller;
if (!STRPREFIX(path, fakesysfscgroupdir)) {
errno = EINVAL;
return -1;
}
controller = path + strlen(fakesysfscgroupdir) + 1;
if (STREQ(controller, "cpu"))
return symlink("cpu,cpuacct", path);
if (STREQ(controller, "cpuacct"))
return symlink("cpu,cpuacct", path);
if (real_mkdir(path, mode) < 0)
return -1;
# define MAKE_FILE(name, value) \
do { \
if (make_file(path, name, value) < 0) \
return -1; \
} while (0)
if (STRPREFIX(controller, "cpu,cpuacct")) {
MAKE_FILE("cpu.cfs_period_us", "100000\n");
MAKE_FILE("cpu.cfs_quota_us", "-1\n");
MAKE_FILE("cpu.shares", "1024\n");
MAKE_FILE("cpuacct.stat",
"user 216687025\n"
"system 43421396\n");
MAKE_FILE("cpuacct.usage", "2787788855799582\n");
MAKE_FILE("cpuacct.usage_percpu",
"7059492996 0 0 0 0 0 0 0 4180532496 0 0 0 0 0 0 0 "
"1957541268 0 0 0 0 0 0 0 2065932204 0 0 0 0 0 0 0 "
"18228689414 0 0 0 0 0 0 0 4245525148 0 0 0 0 0 0 0 "
"2911161568 0 0 0 0 0 0 0 1407758136 0 0 0 0 0 0 0 "
"1836807700 0 0 0 0 0 0 0 1065296618 0 0 0 0 0 0 0 "
"2046213266 0 0 0 0 0 0 0 747889778 0 0 0 0 0 0 0 "
"709566900 0 0 0 0 0 0 0 444777342 0 0 0 0 0 0 0 "
"5683512916 0 0 0 0 0 0 0 635751356 0 0 0 0 0 0 0\n");
} else if (STRPREFIX(controller, "cpuset")) {
if (STREQ(controller, "cpuset"))
MAKE_FILE("cpuset.cpus", "0-1");
else
MAKE_FILE("cpuset.cpus", ""); /* Values don't inherit */
MAKE_FILE("cpuset.memory_migrate", "0\n");
if (STREQ(controller, "cpuset"))
MAKE_FILE("cpuset.mems", "0");
else
MAKE_FILE("cpuset.mems", ""); /* Values don't inherit */
} else if (STRPREFIX(controller, "memory")) {
MAKE_FILE("memory.limit_in_bytes", "9223372036854775807\n");
MAKE_FILE("memory.memsw.limit_in_bytes", ""); /* Not supported */
MAKE_FILE("memory.memsw.usage_in_bytes", ""); /* Not supported */
MAKE_FILE("memory.soft_limit_in_bytes", "9223372036854775807\n");
MAKE_FILE("memory.stat",
"cache 1336619008\n"
"rss 97792000\n"
"mapped_file 42090496\n"
"pgpgin 13022605027\n"
"pgpgout 13023820533\n"
"pgfault 54429417056\n"
"pgmajfault 315715\n"
"inactive_anon 145887232\n"
"active_anon 67100672\n"
"inactive_file 627400704\n"
"active_file 661872640\n"
"unevictable 3690496\n"
"hierarchical_memory_limit 9223372036854775807\n"
"total_cache 1336635392\n"
"total_rss 118689792\n"
"total_mapped_file 42106880\n"
"total_pgpgin 13022606816\n"
"total_pgpgout 13023820793\n"
"total_pgfault 54429422313\n"
"total_pgmajfault 315715\n"
"total_inactive_anon 145891328\n"
"total_active_anon 88010752\n"
"total_inactive_file 627400704\n"
"total_active_file 661872640\n"
"total_unevictable 3690496\n"
"recent_rotated_anon 112807028\n"
"recent_rotated_file 2547948\n"
"recent_scanned_anon 113796164\n"
"recent_scanned_file 8199863\n");
MAKE_FILE("memory.usage_in_bytes", "1455321088\n");
MAKE_FILE("memory.use_hierarchy", "0\n");
} else if (STRPREFIX(controller, "freezer")) {
MAKE_FILE("freezer.state", "THAWED");
} else if (STRPREFIX(controller, "blkio")) {
MAKE_FILE("blkio.throttle.io_service_bytes",
"8:0 Read 59542107136\n"
"8:0 Write 411440480256\n"
"8:0 Sync 248486822912\n"
"8:0 Async 222495764480\n"
"8:0 Total 470982587392\n"
"9:0 Read 59542107137\n"
"9:0 Write 411440480257\n"
"9:0 Sync 248486822912\n"
"9:0 Async 222495764480\n"
"9:0 Total 470982587392\n");
MAKE_FILE("blkio.throttle.io_serviced",
"8:0 Read 4832583\n"
"8:0 Write 36641903\n"
"8:0 Sync 30723171\n"
"8:0 Async 10751315\n"
"8:0 Total 41474486\n"
"9:0 Read 4832584\n"
"9:0 Write 36641904\n"
"9:0 Sync 30723171\n"
"9:0 Async 10751315\n"
"9:0 Total 41474486\n");
MAKE_FILE("blkio.throttle.read_bps_device", "");
MAKE_FILE("blkio.throttle.read_iops_device", "");
MAKE_FILE("blkio.throttle.write_bps_device", "");
MAKE_FILE("blkio.throttle.write_iops_device", "");
MAKE_FILE("blkio.weight", "1000\n");
MAKE_FILE("blkio.weight_device", "");
} else {
errno = EINVAL;
return -1;
}
# undef MAKE_FILE
return 0;
}
static int make_controller_v2(const char *path, mode_t mode)
{
if (!STRPREFIX(path, fakesysfscgroupdir)) {
errno = EINVAL;
return -1;
}
if (real_mkdir(path, mode) < 0 && errno != EEXIST)
return -1;
# define MAKE_FILE(name, value) \
do { \
if (make_file(path, name, value) < 0) \
return -1; \
} while (0)
MAKE_FILE("cgroup.controllers", "cpu io memory\n");
MAKE_FILE("cgroup.subtree_control", "");
MAKE_FILE("cgroup.type", "domain\n");
MAKE_FILE("cpu.max", "max 100000\n");
MAKE_FILE("cpu.stat",
"usage_usec 0\n"
"user_usec 0\n"
"system_usec 0\n"
"nr_periods 0\n"
"nr_throttled 0\n"
"throttled_usec 0\n");
MAKE_FILE("cpu.weight", "100\n");
MAKE_FILE("memory.current", "1455321088\n");
MAKE_FILE("memory.high", "max\n");
MAKE_FILE("memory.max", "max\n");
MAKE_FILE("memory.stat",
"anon 0\n"
"file 0\n"
"kernel_stack 0\n"
"slab 0\n"
"sock 0\n"
"shmem 0\n"
"file_mapped 0\n"
"file_dirty 0\n"
"file_writeback 0\n"
"inactive_anon 0\n"
"active_anon 0\n"
"inactive_file 0\n"
"active_file 0\n"
"unevictable 0\n"
"slab_reclaimable 0\n"
"slab_unreclaimable 0\n"
"pgfault 0\n"
"pgmajfault 0\n"
"pgrefill 0\n"
"pgscan 0\n"
"pgsteal 0\n"
"pgactivate 0\n"
"pgdeactivate 0\n"
"pglazyfree 0\n"
"pglazyfreed 0\n"
"workingset_refault 0\n"
"workingset_activate 0\n"
"workingset_nodereclaim 0\n");
MAKE_FILE("memory.swap.current", "0\n");
MAKE_FILE("memory.swap.max", "max\n");
MAKE_FILE("io.stat", "8:0 rbytes=26828800 wbytes=77062144 rios=2256 wios=7849 dbytes=0 dios=0\n");
MAKE_FILE("io.max", "");
MAKE_FILE("io.weight", "default 100\n");
# undef MAKE_FILE
return 0;
}
static void init_syms(void)
{
if (real_fopen)
return;
VIR_MOCK_REAL_INIT(fopen);
VIR_MOCK_REAL_INIT(access);
VIR_MOCK_REAL_INIT(mkdir);
VIR_MOCK_REAL_INIT(open);
}
static int make_controller(const char *path, mode_t mode)
{
const char *mock;
bool unified = false;
bool hybrid = false;
mock = getenv("VIR_CGROUP_MOCK_MODE");
if (mock) {
if (STREQ(mock, "unified")) {
unified = true;
} else if (STREQ(mock, "hybrid")) {
hybrid = true;
} else if (STRNEQ(mock, "legacy")) {
fprintf(stderr, "invalid mode '%s'\n", mock);
abort();
}
}
if (unified || (hybrid && strstr(path, "unified"))) {
return make_controller_v2(path, mode);
} else {
return make_controller_v1(path, mode);
}
}
static void init_sysfs(void)
{
const char *mock;
char *newfakerootdir;
bool unified = false;
bool hybrid = false;
if (!(newfakerootdir = getenv("LIBVIRT_FAKE_ROOT_DIR"))) {
fprintf(stderr, "Missing LIBVIRT_FAKE_ROOT_DIR env variable\n");
abort();
}
if (fakerootdir && STREQ(fakerootdir, newfakerootdir))
return;
VIR_FREE(fakerootdir);
fakerootdir = g_strdup(newfakerootdir);
mock = getenv("VIR_CGROUP_MOCK_MODE");
if (mock) {
if (STREQ(mock, "unified")) {
unified = true;
} else if (STREQ(mock, "hybrid")) {
hybrid = true;
} else if (STRNEQ(mock, "legacy")) {
fprintf(stderr, "invalid mode '%s'\n", mock);
abort();
}
}
VIR_FREE(fakesysfscgroupdir);
fakesysfscgroupdir = g_strdup_printf("%s%s",
fakerootdir, SYSFS_CGROUP_PREFIX);
if (g_mkdir_with_parents(fakesysfscgroupdir, 0777) < 0) {
fprintf(stderr, "Cannot create %s\n", fakesysfscgroupdir);
abort();
}
# define MAKE_CONTROLLER(subpath) \
do { \
char *path; \
if (asprintf(&path, "%s/%s", fakesysfscgroupdir, subpath) < 0) \
abort(); \
if (make_controller(path, 0755) < 0) { \
fprintf(stderr, "Cannot initialize %s\n", path); \
free(path); \
abort(); \
} \
free(path); \
} while (0)
if (unified) {
MAKE_CONTROLLER("");
} else if (hybrid) {
MAKE_CONTROLLER("unified");
MAKE_CONTROLLER("cpuset");
MAKE_CONTROLLER("freezer");
} else {
MAKE_CONTROLLER("cpu");
MAKE_CONTROLLER("cpuacct");
MAKE_CONTROLLER("cpu,cpuacct");
MAKE_CONTROLLER("cpuset");
MAKE_CONTROLLER("blkio");
MAKE_CONTROLLER("memory");
MAKE_CONTROLLER("freezer");
if (make_file(fakesysfscgroupdir,
SYSFS_CPU_PRESENT_MOCKED, "8-23,48-159\n") < 0)
abort();
}
}
FILE *fopen(const char *path, const char *mode)
{
char *filepath = NULL;
const char *type = NULL;
FILE *rc = NULL;
const char *filename = getenv("VIR_CGROUP_MOCK_FILENAME");
init_syms();
if (STREQ(path, "/proc/mounts")) {
if (STREQ(mode, "r")) {
type = "mounts";
} else {
errno = EACCES;
return NULL;
}
}
if (STREQ(path, "/proc/cgroups")) {
if (STREQ(mode, "r")) {
type = "cgroups";
} else {
errno = EACCES;
return NULL;
}
}
if (STREQ(path, "/proc/self/cgroup")) {
if (STREQ(mode, "r")) {
type = "self.cgroup";
} else {
errno = EACCES;
return NULL;
}
}
if (type) {
if (!filename) {
errno = EACCES;
return NULL;
}
filepath = g_strdup_printf("%s/vircgroupdata/%s.%s",
abs_srcdir, filename, type);
rc = real_fopen(filepath, mode);
free(filepath);
return rc;
}
return real_fopen(path, mode);
}
int access(const char *path, int mode)
{
int ret;
init_syms();
if (STRPREFIX(path, SYSFS_CGROUP_PREFIX)) {
char *newpath;
init_sysfs();
if (asprintf(&newpath, "%s%s",
fakesysfscgroupdir,
path + strlen(SYSFS_CGROUP_PREFIX)) < 0) {
errno = ENOMEM;
return -1;
}
ret = real_access(newpath, mode);
free(newpath);
} else if (STREQ(path, "/proc/cgroups") ||
STREQ(path, "/proc/self/cgroup") ||
STREQ(path, SYSFS_CPU_PRESENT)) {
/* These files are readable for all. */
ret = (mode == F_OK || mode == R_OK) ? 0 : -1;
} else if (STREQ(path, "/proc/mounts")) {
/* This one is accessible anytime for anybody. In fact, it's just
* a symlink to /proc/self/mounts. */
ret = 0;
} else {
ret = real_access(path, mode);
}
return ret;
}
# define VIR_MOCK_STAT_HOOK \
do { \
if (STRPREFIX(path, fakedevicedir0)) { \
sb->st_mode = S_IFBLK; \
sb->st_rdev = makedev(8, 0); \
return 0; \
} else if (STRPREFIX(path, fakedevicedir1)) { \
sb->st_mode = S_IFBLK; \
sb->st_rdev = makedev(9, 0); \
return 0; \
} \
} while (0)
# include "virmockstathelpers.c"
static int
virMockStatRedirect(const char *path, char **newpath)
{
if (STREQ(path, SYSFS_CPU_PRESENT)) {
init_sysfs();
if (asprintf(newpath, "%s/%s",
fakesysfscgroupdir,
SYSFS_CPU_PRESENT_MOCKED) < 0)
return -1;
} else if (STRPREFIX(path, SYSFS_CGROUP_PREFIX)) {
init_sysfs();
if (asprintf(newpath, "%s%s",
fakesysfscgroupdir,
path + strlen(SYSFS_CGROUP_PREFIX)) < 0)
return -1;
}
return 0;
}
int mkdir(const char *path, mode_t mode)
{
int ret;
init_syms();
if (STRPREFIX(path, SYSFS_CGROUP_PREFIX)) {
char *newpath;
init_sysfs();
if (asprintf(&newpath, "%s%s",
fakesysfscgroupdir,
path + strlen(SYSFS_CGROUP_PREFIX)) < 0) {
errno = ENOMEM;
return -1;
}
ret = make_controller(newpath, mode);
free(newpath);
} else {
ret = real_mkdir(path, mode);
}
return ret;
}
int open(const char *path, int flags, ...)
{
int ret;
char *newpath = NULL;
init_syms();
if (STREQ(path, SYSFS_CPU_PRESENT)) {
init_sysfs();
if (asprintf(&newpath, "%s/%s",
fakesysfscgroupdir,
SYSFS_CPU_PRESENT_MOCKED) < 0) {
errno = ENOMEM;
return -1;
}
}
if (STRPREFIX(path, SYSFS_CGROUP_PREFIX)) {
init_sysfs();
if (asprintf(&newpath, "%s%s",
fakesysfscgroupdir,
path + strlen(SYSFS_CGROUP_PREFIX)) < 0) {
errno = ENOMEM;
return -1;
}
}
if (flags & O_CREAT) {
va_list ap;
mode_t mode;
va_start(ap, flags);
mode = (mode_t) va_arg(ap, int);
va_end(ap);
ret = real_open(newpath ? newpath : path, flags, mode);
} else {
ret = real_open(newpath ? newpath : path, flags);
}
free(newpath);
return ret;
}
bool
virCgroupV2DevicesAvailable(virCgroup *group G_GNUC_UNUSED)
{
return true;
}
#else
/* Nothing to override on non-__linux__ platforms */
#endif