libvirt/src/qemu/qemu_cgroup.c
Jiri Denemark 774eb45be6 qemu: Don't ignore CPU tuning config if required cgroups are missing
When domain XML contains any of the elements for setting up CPU
scheduling parameters (period, quota, emulator_period, or
emulator_quota) we need cpu cgroup to enforce the configuration.
However, the existing code would just ignore silently such settings if
either cgroups were not available at all cpu cgroup was not available.
Moreover, APIs for manipulating CPU scheduler parameters were already
failing if cpu cgroup was not available. This patch makes cpu cgroup
mandatory for all domains that use CPU scheduling elements in their XML.
2012-08-31 13:24:02 +02:00

770 lines
25 KiB
C

/*
* qemu_cgroup.c: QEMU cgroup management
*
* Copyright (C) 2006-2012 Red Hat, Inc.
* Copyright (C) 2006 Daniel P. Berrange
*
* 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/>.
*
* Author: Daniel P. Berrange <berrange@redhat.com>
*/
#include <config.h>
#include "qemu_cgroup.h"
#include "qemu_domain.h"
#include "cgroup.h"
#include "logging.h"
#include "memory.h"
#include "virterror_internal.h"
#include "util.h"
#include "domain_audit.h"
#define VIR_FROM_THIS VIR_FROM_QEMU
static const char *const defaultDeviceACL[] = {
"/dev/null", "/dev/full", "/dev/zero",
"/dev/random", "/dev/urandom",
"/dev/ptmx", "/dev/kvm", "/dev/kqemu",
"/dev/rtc", "/dev/hpet",
NULL,
};
#define DEVICE_PTY_MAJOR 136
#define DEVICE_SND_MAJOR 116
bool qemuCgroupControllerActive(struct qemud_driver *driver,
int controller)
{
if (driver->cgroup == NULL)
return false;
if (controller < 0 || controller >= VIR_CGROUP_CONTROLLER_LAST)
return false;
if (!virCgroupMounted(driver->cgroup, controller))
return false;
if (driver->cgroupControllers & (1 << controller))
return true;
return false;
}
static int
qemuSetupDiskPathAllow(virDomainDiskDefPtr disk,
const char *path,
size_t depth ATTRIBUTE_UNUSED,
void *opaque)
{
qemuCgroupData *data = opaque;
int rc;
VIR_DEBUG("Process path %s for disk", path);
rc = virCgroupAllowDevicePath(data->cgroup, path,
(disk->readonly ? VIR_CGROUP_DEVICE_READ
: VIR_CGROUP_DEVICE_RW));
virDomainAuditCgroupPath(data->vm, data->cgroup, "allow", path,
disk->readonly ? "r" : "rw", rc);
if (rc < 0) {
if (rc == -EACCES) { /* Get this for root squash NFS */
VIR_DEBUG("Ignoring EACCES for %s", path);
} else {
virReportSystemError(-rc,
_("Unable to allow access for disk path %s"),
path);
return -1;
}
}
return 0;
}
int qemuSetupDiskCgroup(struct qemud_driver *driver,
virDomainObjPtr vm,
virCgroupPtr cgroup,
virDomainDiskDefPtr disk)
{
qemuCgroupData data = { vm, cgroup };
return virDomainDiskDefForeachPath(disk,
driver->allowDiskFormatProbing,
true,
driver->user, driver->group,
qemuSetupDiskPathAllow,
&data);
}
static int
qemuTeardownDiskPathDeny(virDomainDiskDefPtr disk ATTRIBUTE_UNUSED,
const char *path,
size_t depth ATTRIBUTE_UNUSED,
void *opaque)
{
qemuCgroupData *data = opaque;
int rc;
VIR_DEBUG("Process path %s for disk", path);
rc = virCgroupDenyDevicePath(data->cgroup, path,
VIR_CGROUP_DEVICE_RWM);
virDomainAuditCgroupPath(data->vm, data->cgroup, "deny", path, "rwm", rc);
if (rc < 0) {
if (rc == -EACCES) { /* Get this for root squash NFS */
VIR_DEBUG("Ignoring EACCES for %s", path);
} else {
virReportSystemError(-rc,
_("Unable to deny access for disk path %s"),
path);
return -1;
}
}
return 0;
}
int qemuTeardownDiskCgroup(struct qemud_driver *driver,
virDomainObjPtr vm,
virCgroupPtr cgroup,
virDomainDiskDefPtr disk)
{
qemuCgroupData data = { vm, cgroup };
return virDomainDiskDefForeachPath(disk,
driver->allowDiskFormatProbing,
true,
driver->user, driver->group,
qemuTeardownDiskPathDeny,
&data);
}
static int
qemuSetupChardevCgroup(virDomainDefPtr def,
virDomainChrDefPtr dev,
void *opaque)
{
qemuCgroupData *data = opaque;
int rc;
if (dev->source.type != VIR_DOMAIN_CHR_TYPE_DEV)
return 0;
VIR_DEBUG("Process path '%s' for disk", dev->source.data.file.path);
rc = virCgroupAllowDevicePath(data->cgroup, dev->source.data.file.path,
VIR_CGROUP_DEVICE_RW);
virDomainAuditCgroupPath(data->vm, data->cgroup, "allow",
dev->source.data.file.path, "rw", rc);
if (rc < 0) {
virReportSystemError(-rc,
_("Unable to allow device %s for %s"),
dev->source.data.file.path, def->name);
return -1;
}
return 0;
}
int qemuSetupHostUsbDeviceCgroup(usbDevice *dev ATTRIBUTE_UNUSED,
const char *path,
void *opaque)
{
qemuCgroupData *data = opaque;
int rc;
VIR_DEBUG("Process path '%s' for USB device", path);
rc = virCgroupAllowDevicePath(data->cgroup, path,
VIR_CGROUP_DEVICE_RW);
virDomainAuditCgroupPath(data->vm, data->cgroup, "allow", path, "rw", rc);
if (rc < 0) {
virReportSystemError(-rc,
_("Unable to allow device %s"),
path);
return -1;
}
return 0;
}
int qemuSetupCgroup(struct qemud_driver *driver,
virDomainObjPtr vm,
char *nodemask)
{
virCgroupPtr cgroup = NULL;
int rc;
unsigned int i;
const char *const *deviceACL =
driver->cgroupDeviceACL ?
(const char *const *)driver->cgroupDeviceACL :
defaultDeviceACL;
if (driver->cgroup == NULL)
return 0; /* Not supported, so claim success */
rc = virCgroupForDomain(driver->cgroup, vm->def->name, &cgroup, 1);
if (rc != 0) {
virReportSystemError(-rc,
_("Unable to create cgroup for %s"),
vm->def->name);
goto cleanup;
}
if (qemuCgroupControllerActive(driver, VIR_CGROUP_CONTROLLER_DEVICES)) {
qemuCgroupData data = { vm, cgroup };
rc = virCgroupDenyAllDevices(cgroup);
virDomainAuditCgroup(vm, cgroup, "deny", "all", rc == 0);
if (rc != 0) {
if (rc == -EPERM) {
VIR_WARN("Group devices ACL is not accessible, disabling whitelisting");
goto done;
}
virReportSystemError(-rc,
_("Unable to deny all devices for %s"), vm->def->name);
goto cleanup;
}
for (i = 0; i < vm->def->ndisks ; i++) {
if (qemuSetupDiskCgroup(driver, vm, cgroup, vm->def->disks[i]) < 0)
goto cleanup;
}
rc = virCgroupAllowDeviceMajor(cgroup, 'c', DEVICE_PTY_MAJOR,
VIR_CGROUP_DEVICE_RW);
virDomainAuditCgroupMajor(vm, cgroup, "allow", DEVICE_PTY_MAJOR,
"pty", "rw", rc == 0);
if (rc != 0) {
virReportSystemError(-rc, "%s",
_("unable to allow /dev/pts/ devices"));
goto cleanup;
}
if (vm->def->nsounds &&
(!vm->def->ngraphics ||
((vm->def->graphics[0]->type == VIR_DOMAIN_GRAPHICS_TYPE_VNC &&
driver->vncAllowHostAudio) ||
(vm->def->graphics[0]->type == VIR_DOMAIN_GRAPHICS_TYPE_SDL)))) {
rc = virCgroupAllowDeviceMajor(cgroup, 'c', DEVICE_SND_MAJOR,
VIR_CGROUP_DEVICE_RW);
virDomainAuditCgroupMajor(vm, cgroup, "allow", DEVICE_SND_MAJOR,
"sound", "rw", rc == 0);
if (rc != 0) {
virReportSystemError(-rc, "%s",
_("unable to allow /dev/snd/ devices"));
goto cleanup;
}
}
for (i = 0; deviceACL[i] != NULL ; i++) {
rc = virCgroupAllowDevicePath(cgroup, deviceACL[i],
VIR_CGROUP_DEVICE_RW);
virDomainAuditCgroupPath(vm, cgroup, "allow", deviceACL[i], "rw", rc);
if (rc < 0 &&
rc != -ENOENT) {
virReportSystemError(-rc,
_("unable to allow device %s"),
deviceACL[i]);
goto cleanup;
}
}
if (virDomainChrDefForeach(vm->def,
true,
qemuSetupChardevCgroup,
&data) < 0)
goto cleanup;
for (i = 0; i < vm->def->nhostdevs; i++) {
virDomainHostdevDefPtr hostdev = vm->def->hostdevs[i];
usbDevice *usb;
if (hostdev->mode != VIR_DOMAIN_HOSTDEV_MODE_SUBSYS)
continue;
if (hostdev->source.subsys.type != VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_USB)
continue;
if ((usb = usbGetDevice(hostdev->source.subsys.u.usb.bus,
hostdev->source.subsys.u.usb.device)) == NULL)
goto cleanup;
if (usbDeviceFileIterate(usb, qemuSetupHostUsbDeviceCgroup,
&data) < 0)
goto cleanup;
}
}
if (vm->def->blkio.weight != 0) {
if (qemuCgroupControllerActive(driver, VIR_CGROUP_CONTROLLER_BLKIO)) {
rc = virCgroupSetBlkioWeight(cgroup, vm->def->blkio.weight);
if(rc != 0) {
virReportSystemError(-rc,
_("Unable to set io weight for domain %s"),
vm->def->name);
goto cleanup;
}
} else {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("Block I/O tuning is not available on this host"));
goto cleanup;
}
}
if (vm->def->blkio.ndevices) {
if (qemuCgroupControllerActive(driver, VIR_CGROUP_CONTROLLER_BLKIO)) {
for (i = 0; i < vm->def->blkio.ndevices; i++) {
virBlkioDeviceWeightPtr dw = &vm->def->blkio.devices[i];
if (!dw->weight)
continue;
rc = virCgroupSetBlkioDeviceWeight(cgroup, dw->path,
dw->weight);
if (rc != 0) {
virReportSystemError(-rc,
_("Unable to set io device weight "
"for domain %s"),
vm->def->name);
goto cleanup;
}
}
} else {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("Block I/O tuning is not available on this host"));
goto cleanup;
}
}
if (qemuCgroupControllerActive(driver, VIR_CGROUP_CONTROLLER_MEMORY)) {
unsigned long long hard_limit = vm->def->mem.hard_limit;
if (!hard_limit) {
/* If there is no hard_limit set, set a reasonable
* one to avoid system trashing caused by exploited qemu.
* As 'reasonable limit' has been chosen:
* (1 + k) * (domain memory + total video memory) + F
* where k = 0.02 and F = 200MB. */
hard_limit = vm->def->mem.max_balloon;
for (i = 0; i < vm->def->nvideos; i++)
hard_limit += vm->def->videos[i]->vram;
hard_limit = hard_limit * 1.02 + 204800;
}
rc = virCgroupSetMemoryHardLimit(cgroup, hard_limit);
if (rc != 0) {
virReportSystemError(-rc,
_("Unable to set memory hard limit for domain %s"),
vm->def->name);
goto cleanup;
}
if (vm->def->mem.soft_limit != 0) {
rc = virCgroupSetMemorySoftLimit(cgroup, vm->def->mem.soft_limit);
if (rc != 0) {
virReportSystemError(-rc,
_("Unable to set memory soft limit for domain %s"),
vm->def->name);
goto cleanup;
}
}
if (vm->def->mem.swap_hard_limit != 0) {
rc = virCgroupSetMemSwapHardLimit(cgroup, vm->def->mem.swap_hard_limit);
if (rc != 0) {
virReportSystemError(-rc,
_("Unable to set swap hard limit for domain %s"),
vm->def->name);
goto cleanup;
}
}
} else if (vm->def->mem.hard_limit != 0 ||
vm->def->mem.soft_limit != 0 ||
vm->def->mem.swap_hard_limit != 0) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("Memory cgroup is not available on this host"));
} else {
VIR_WARN("Could not autoset a RSS limit for domain %s", vm->def->name);
}
if (vm->def->cputune.shares != 0) {
if (qemuCgroupControllerActive(driver, VIR_CGROUP_CONTROLLER_CPU)) {
rc = virCgroupSetCpuShares(cgroup, vm->def->cputune.shares);
if(rc != 0) {
virReportSystemError(-rc,
_("Unable to set io cpu shares for domain %s"),
vm->def->name);
goto cleanup;
}
} else {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("CPU tuning is not available on this host"));
}
}
if ((vm->def->numatune.memory.nodemask ||
(vm->def->numatune.memory.placement_mode ==
VIR_DOMAIN_NUMATUNE_MEM_PLACEMENT_MODE_AUTO)) &&
vm->def->numatune.memory.mode == VIR_DOMAIN_NUMATUNE_MEM_STRICT &&
qemuCgroupControllerActive(driver, VIR_CGROUP_CONTROLLER_CPUSET)) {
char *mask = NULL;
if (vm->def->numatune.memory.placement_mode ==
VIR_DOMAIN_NUMATUNE_MEM_PLACEMENT_MODE_AUTO)
mask = virDomainCpuSetFormat(nodemask, VIR_DOMAIN_CPUMASK_LEN);
else
mask = virDomainCpuSetFormat(vm->def->numatune.memory.nodemask,
VIR_DOMAIN_CPUMASK_LEN);
if (!mask) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("failed to convert memory nodemask"));
goto cleanup;
}
rc = virCgroupSetCpusetMems(cgroup, mask);
VIR_FREE(mask);
if (rc != 0) {
virReportSystemError(-rc,
_("Unable to set cpuset.mems for domain %s"),
vm->def->name);
goto cleanup;
}
}
done:
virCgroupFree(&cgroup);
return 0;
cleanup:
if (cgroup) {
virCgroupRemove(cgroup);
virCgroupFree(&cgroup);
}
return -1;
}
int qemuSetupCgroupVcpuBW(virCgroupPtr cgroup, unsigned long long period,
long long quota)
{
int rc;
unsigned long long old_period;
if (period == 0 && quota == 0)
return 0;
if (period) {
/* get old period, and we can rollback if set quota failed */
rc = virCgroupGetCpuCfsPeriod(cgroup, &old_period);
if (rc < 0) {
virReportSystemError(-rc,
"%s", _("Unable to get cpu bandwidth period"));
return -1;
}
rc = virCgroupSetCpuCfsPeriod(cgroup, period);
if (rc < 0) {
virReportSystemError(-rc,
"%s", _("Unable to set cpu bandwidth period"));
return -1;
}
}
if (quota) {
rc = virCgroupSetCpuCfsQuota(cgroup, quota);
if (rc < 0) {
virReportSystemError(-rc,
"%s", _("Unable to set cpu bandwidth quota"));
goto cleanup;
}
}
return 0;
cleanup:
if (period) {
rc = virCgroupSetCpuCfsPeriod(cgroup, old_period);
if (rc < 0)
virReportSystemError(-rc, "%s",
_("Unable to rollback cpu bandwidth period"));
}
return -1;
}
int qemuSetupCgroupVcpuPin(virCgroupPtr cgroup,
virDomainVcpuPinDefPtr *vcpupin,
int nvcpupin,
int vcpuid)
{
int i;
for (i = 0; i < nvcpupin; i++) {
if (vcpuid == vcpupin[i]->vcpuid) {
return qemuSetupCgroupEmulatorPin(cgroup, vcpupin[i]);
}
}
return -1;
}
int qemuSetupCgroupEmulatorPin(virCgroupPtr cgroup,
virDomainVcpuPinDefPtr vcpupin)
{
int rc = 0;
char *new_cpus = NULL;
new_cpus = virDomainCpuSetFormat(vcpupin->cpumask,
VIR_DOMAIN_CPUMASK_LEN);
if (!new_cpus) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("failed to convert cpu mask"));
rc = -1;
goto cleanup;
}
rc = virCgroupSetCpusetCpus(cgroup, new_cpus);
if (rc < 0) {
virReportSystemError(-rc,
"%s",
_("Unable to set cpuset.cpus"));
goto cleanup;
}
cleanup:
VIR_FREE(new_cpus);
return rc;
}
int qemuSetupCgroupForVcpu(struct qemud_driver *driver, virDomainObjPtr vm)
{
virCgroupPtr cgroup = NULL;
virCgroupPtr cgroup_vcpu = NULL;
qemuDomainObjPrivatePtr priv = vm->privateData;
virDomainDefPtr def = vm->def;
int rc;
unsigned int i;
unsigned long long period = vm->def->cputune.period;
long long quota = vm->def->cputune.quota;
if ((period || quota) &&
(!driver->cgroup ||
!qemuCgroupControllerActive(driver, VIR_CGROUP_CONTROLLER_CPU))) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("cgroup cpu is required for scheduler tuning"));
return -1;
}
/* We are trying to setup cgroups for CPU pinning, which can also be done
* with virProcessInfoSetAffinity, thus the lack of cgroups is not fatal
* here.
*/
if (driver->cgroup == NULL)
return 0;
rc = virCgroupForDomain(driver->cgroup, vm->def->name, &cgroup, 0);
if (rc != 0) {
virReportSystemError(-rc,
_("Unable to find cgroup for %s"),
vm->def->name);
goto cleanup;
}
if (priv->nvcpupids == 0 || priv->vcpupids[0] == vm->pid) {
/* If we don't know VCPU<->PID mapping or all vcpu runs in the same
* thread, we cannot control each vcpu.
*/
VIR_WARN("Unable to get vcpus' pids.");
virCgroupFree(&cgroup);
return 0;
}
for (i = 0; i < priv->nvcpupids; i++) {
rc = virCgroupForVcpu(cgroup, i, &cgroup_vcpu, 1);
if (rc < 0) {
virReportSystemError(-rc,
_("Unable to create vcpu cgroup for %s(vcpu:"
" %d)"),
vm->def->name, i);
goto cleanup;
}
/* move the thread for vcpu to sub dir */
rc = virCgroupAddTask(cgroup_vcpu, priv->vcpupids[i]);
if (rc < 0) {
virReportSystemError(-rc,
_("unable to add vcpu %d task %d to cgroup"),
i, priv->vcpupids[i]);
goto cleanup;
}
if (period || quota) {
if (qemuSetupCgroupVcpuBW(cgroup_vcpu, period, quota) < 0)
goto cleanup;
}
/* Set vcpupin in cgroup if vcpupin xml is provided */
if (def->cputune.nvcpupin &&
qemuCgroupControllerActive(driver, VIR_CGROUP_CONTROLLER_CPUSET) &&
qemuSetupCgroupVcpuPin(cgroup_vcpu,
def->cputune.vcpupin,
def->cputune.nvcpupin,
i) < 0)
goto cleanup;
virCgroupFree(&cgroup_vcpu);
}
virCgroupFree(&cgroup);
return 0;
cleanup:
if (cgroup_vcpu) {
virCgroupRemove(cgroup_vcpu);
virCgroupFree(&cgroup_vcpu);
}
if (cgroup) {
virCgroupRemove(cgroup);
virCgroupFree(&cgroup);
}
return -1;
}
int qemuSetupCgroupForEmulator(struct qemud_driver *driver,
virDomainObjPtr vm)
{
virCgroupPtr cgroup = NULL;
virCgroupPtr cgroup_emulator = NULL;
virDomainDefPtr def = vm->def;
unsigned long long period = vm->def->cputune.emulator_period;
long long quota = vm->def->cputune.emulator_quota;
int rc, i;
if ((period || quota) &&
(!driver->cgroup ||
!qemuCgroupControllerActive(driver, VIR_CGROUP_CONTROLLER_CPU))) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("cgroup cpu is required for scheduler tuning"));
return -1;
}
if (driver->cgroup == NULL)
return 0; /* Not supported, so claim success */
rc = virCgroupForDomain(driver->cgroup, vm->def->name, &cgroup, 0);
if (rc != 0) {
virReportSystemError(-rc,
_("Unable to find cgroup for %s"),
vm->def->name);
goto cleanup;
}
rc = virCgroupForEmulator(cgroup, &cgroup_emulator, 1);
if (rc < 0) {
virReportSystemError(-rc,
_("Unable to create emulator cgroup for %s"),
vm->def->name);
goto cleanup;
}
for (i = 0; i < VIR_CGROUP_CONTROLLER_LAST; i++) {
if (!qemuCgroupControllerActive(driver, i))
continue;
rc = virCgroupMoveTask(cgroup, cgroup_emulator, i);
if (rc < 0) {
virReportSystemError(-rc,
_("Unable to move tasks from domain cgroup to "
"emulator cgroup in controller %d for %s"),
i, vm->def->name);
goto cleanup;
}
}
if (def->cputune.emulatorpin &&
qemuCgroupControllerActive(driver, VIR_CGROUP_CONTROLLER_CPUSET) &&
qemuSetupCgroupEmulatorPin(cgroup_emulator, def->cputune.emulatorpin) < 0)
goto cleanup;
if (period || quota) {
if (qemuCgroupControllerActive(driver, VIR_CGROUP_CONTROLLER_CPU)) {
if (qemuSetupCgroupVcpuBW(cgroup_emulator, period, quota) < 0)
goto cleanup;
}
}
virCgroupFree(&cgroup_emulator);
virCgroupFree(&cgroup);
return 0;
cleanup:
if (cgroup_emulator) {
virCgroupRemove(cgroup_emulator);
virCgroupFree(&cgroup_emulator);
}
if (cgroup) {
virCgroupRemove(cgroup);
virCgroupFree(&cgroup);
}
return rc;
}
int qemuRemoveCgroup(struct qemud_driver *driver,
virDomainObjPtr vm,
int quiet)
{
virCgroupPtr cgroup;
int rc;
if (driver->cgroup == NULL)
return 0; /* Not supported, so claim success */
rc = virCgroupForDomain(driver->cgroup, vm->def->name, &cgroup, 0);
if (rc != 0) {
if (!quiet)
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Unable to find cgroup for %s"),
vm->def->name);
return rc;
}
rc = virCgroupRemove(cgroup);
virCgroupFree(&cgroup);
return rc;
}
int qemuAddToCgroup(struct qemud_driver *driver,
virDomainDefPtr def)
{
virCgroupPtr cgroup = NULL;
int ret = -1;
int rc;
if (driver->cgroup == NULL)
return 0; /* Not supported, so claim success */
rc = virCgroupForDomain(driver->cgroup, def->name, &cgroup, 0);
if (rc != 0) {
virReportSystemError(-rc,
_("unable to find cgroup for domain %s"),
def->name);
goto cleanup;
}
rc = virCgroupAddTask(cgroup, getpid());
if (rc != 0) {
virReportSystemError(-rc,
_("unable to add domain %s task %d to cgroup"),
def->name, getpid());
goto cleanup;
}
ret = 0;
cleanup:
virCgroupFree(&cgroup);
return ret;
}