libvirt/src/util/cgroup.c
Eric Blake 8e22e08935 build: rename files.h to virfile.h
In preparation for a future patch adding new virFile APIs.

* src/util/files.h, src/util/files.c: Move...
* src/util/virfile.h, src/util/virfile.c: ...here, and rename
functions to virFile prefix.  Macro names are intentionally
left alone.
* *.c: All '#include "files.h"' uses changed.
* src/Makefile.am (UTIL_SOURCES): Reflect rename.
* cfg.mk (exclude_file_name_regexp--sc_prohibit_close): Likewise.
* src/libvirt_private.syms: Likewise.
* docs/hacking.html.in: Likewise.
* HACKING: Regenerate.
2011-07-21 10:34:51 -06:00

1719 lines
45 KiB
C

/*
* cgroup.c: Tools for managing cgroups
*
* Copyright (C) 2010-2011 Red Hat, Inc.
* Copyright IBM Corp. 2008
*
* See COPYING.LIB for the License of this software
*
* Authors:
* Dan Smith <danms@us.ibm.com>
*/
#include <config.h>
#include <stdio.h>
#include <stdint.h>
#if defined HAVE_MNTENT_H && defined HAVE_GETMNTENT_R
# include <mntent.h>
#endif
#include <fcntl.h>
#include <string.h>
#include <errno.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <signal.h>
#include <libgen.h>
#include <dirent.h>
#include "internal.h"
#include "util.h"
#include "memory.h"
#include "cgroup.h"
#include "logging.h"
#include "virfile.h"
#include "hash.h"
#define CGROUP_MAX_VAL 512
VIR_ENUM_IMPL(virCgroupController, VIR_CGROUP_CONTROLLER_LAST,
"cpu", "cpuacct", "cpuset", "memory", "devices",
"freezer", "blkio");
struct virCgroupController {
int type;
char *mountPoint;
char *placement;
};
struct virCgroup {
char *path;
struct virCgroupController controllers[VIR_CGROUP_CONTROLLER_LAST];
};
typedef enum {
VIR_CGROUP_NONE = 0, /* create subdir under each cgroup if possible. */
VIR_CGROUP_MEM_HIERACHY = 1 << 0, /* call virCgroupSetMemoryUseHierarchy
* before creating subcgroups and
* attaching tasks
*/
VIR_CGROUP_VCPU = 1 << 1, /* create subdir only under the cgroup cpu,
* cpuacct and cpuset if possible. */
} virCgroupFlags;
/**
* virCgroupFree:
*
* @group: The group structure to free
*/
void virCgroupFree(virCgroupPtr *group)
{
int i;
if (*group == NULL)
return;
for (i = 0 ; i < VIR_CGROUP_CONTROLLER_LAST ; i++) {
VIR_FREE((*group)->controllers[i].mountPoint);
VIR_FREE((*group)->controllers[i].placement);
}
VIR_FREE((*group)->path);
VIR_FREE(*group);
}
/**
* virCgroupMounted: query whether a cgroup subsystem is mounted or not
*
* @cgroup: The group structure to be queried
* @controller: cgroup subsystem id
*
* Returns true if a cgroup is subsystem is mounted.
*/
bool virCgroupMounted(virCgroupPtr cgroup, int controller)
{
return cgroup->controllers[controller].mountPoint != NULL;
}
#if defined HAVE_MNTENT_H && defined HAVE_GETMNTENT_R
/*
* Process /proc/mounts figuring out what controllers are
* mounted and where
*/
static int virCgroupDetectMounts(virCgroupPtr group)
{
int i;
FILE *mounts = NULL;
struct mntent entry;
char buf[CGROUP_MAX_VAL];
mounts = fopen("/proc/mounts", "r");
if (mounts == NULL) {
VIR_ERROR(_("Unable to open /proc/mounts"));
return -ENOENT;
}
while (getmntent_r(mounts, &entry, buf, sizeof(buf)) != NULL) {
if (STRNEQ(entry.mnt_type, "cgroup"))
continue;
for (i = 0 ; i < VIR_CGROUP_CONTROLLER_LAST ; i++) {
const char *typestr = virCgroupControllerTypeToString(i);
int typelen = strlen(typestr);
char *tmp = entry.mnt_opts;
while (tmp) {
char *next = strchr(tmp, ',');
int len;
if (next) {
len = next-tmp;
next++;
} else {
len = strlen(tmp);
}
if (typelen == len && STREQLEN(typestr, tmp, len) &&
!(group->controllers[i].mountPoint = strdup(entry.mnt_dir)))
goto no_memory;
tmp = next;
}
}
}
VIR_FORCE_FCLOSE(mounts);
return 0;
no_memory:
VIR_FORCE_FCLOSE(mounts);
return -ENOMEM;
}
/*
* Process /proc/self/cgroup figuring out what cgroup
* sub-path the current process is assigned to. ie not
* neccessarily in the root
*/
static int virCgroupDetectPlacement(virCgroupPtr group)
{
int i;
FILE *mapping = NULL;
char line[1024];
mapping = fopen("/proc/self/cgroup", "r");
if (mapping == NULL) {
VIR_ERROR(_("Unable to open /proc/self/cgroup"));
return -ENOENT;
}
while (fgets(line, sizeof(line), mapping) != NULL) {
char *controllers = strchr(line, ':');
char *path = controllers ? strchr(controllers+1, ':') : NULL;
char *nl = path ? strchr(path, '\n') : NULL;
if (!controllers || !path)
continue;
if (nl)
*nl = '\0';
*path = '\0';
controllers++;
path++;
for (i = 0 ; i < VIR_CGROUP_CONTROLLER_LAST ; i++) {
const char *typestr = virCgroupControllerTypeToString(i);
int typelen = strlen(typestr);
char *tmp = controllers;
while (tmp) {
char *next = strchr(tmp, ',');
int len;
if (next) {
len = next-tmp;
next++;
} else {
len = strlen(tmp);
}
if (typelen == len && STREQLEN(typestr, tmp, len) &&
!(group->controllers[i].placement = strdup(STREQ(path, "/") ? "" : path)))
goto no_memory;
tmp = next;
}
}
}
VIR_FORCE_FCLOSE(mapping);
return 0;
no_memory:
VIR_FORCE_FCLOSE(mapping);
return -ENOMEM;
}
static int virCgroupDetect(virCgroupPtr group)
{
int any = 0;
int rc;
int i;
rc = virCgroupDetectMounts(group);
if (rc < 0) {
VIR_ERROR(_("Failed to detect mounts for %s"), group->path);
return rc;
}
/* Check that at least 1 controller is available */
for (i = 0 ; i < VIR_CGROUP_CONTROLLER_LAST ; i++) {
if (group->controllers[i].mountPoint != NULL)
any = 1;
}
if (!any)
return -ENXIO;
rc = virCgroupDetectPlacement(group);
if (rc == 0) {
/* Check that for every mounted controller, we found our placement */
for (i = 0 ; i < VIR_CGROUP_CONTROLLER_LAST ; i++) {
if (!group->controllers[i].mountPoint)
continue;
if (!group->controllers[i].placement) {
VIR_ERROR(_("Could not find placement for controller %s at %s"),
virCgroupControllerTypeToString(i),
group->controllers[i].placement);
rc = -ENOENT;
break;
}
VIR_DEBUG("Detected mount/mapping %i:%s at %s in %s", i,
virCgroupControllerTypeToString(i),
group->controllers[i].mountPoint,
group->controllers[i].placement);
}
} else {
VIR_ERROR(_("Failed to detect mapping for %s"), group->path);
}
return rc;
}
#endif
int virCgroupPathOfController(virCgroupPtr group,
int controller,
const char *key,
char **path)
{
if (controller == -1) {
int i;
for (i = 0 ; i < VIR_CGROUP_CONTROLLER_LAST ; i++) {
if (group->controllers[i].mountPoint &&
group->controllers[i].placement) {
controller = i;
break;
}
}
}
if (controller == -1)
return -ENOSYS;
if (group->controllers[controller].mountPoint == NULL)
return -ENOENT;
if (group->controllers[controller].placement == NULL)
return -ENOENT;
if (virAsprintf(path, "%s%s%s/%s",
group->controllers[controller].mountPoint,
group->controllers[controller].placement,
STREQ(group->path, "/") ? "" : group->path,
key ? key : "") == -1)
return -ENOMEM;
return 0;
}
static int virCgroupSetValueStr(virCgroupPtr group,
int controller,
const char *key,
const char *value)
{
int rc = 0;
char *keypath = NULL;
rc = virCgroupPathOfController(group, controller, key, &keypath);
if (rc != 0)
return rc;
VIR_DEBUG("Set value '%s' to '%s'", keypath, value);
rc = virFileWriteStr(keypath, value, 0);
if (rc < 0) {
rc = -errno;
VIR_DEBUG("Failed to write value '%s': %m", value);
} else {
rc = 0;
}
VIR_FREE(keypath);
return rc;
}
static int virCgroupGetValueStr(virCgroupPtr group,
int controller,
const char *key,
char **value)
{
int rc;
char *keypath = NULL;
*value = NULL;
rc = virCgroupPathOfController(group, controller, key, &keypath);
if (rc != 0) {
VIR_DEBUG("No path of %s, %s", group->path, key);
return rc;
}
VIR_DEBUG("Get value %s", keypath);
rc = virFileReadAll(keypath, 1024, value);
if (rc < 0) {
rc = -errno;
VIR_DEBUG("Failed to read %s: %m\n", keypath);
} else {
/* Terminated with '\n' has sometimes harmful effects to the caller */
char *p = strchr(*value, '\n');
if (p) *p = '\0';
rc = 0;
}
VIR_FREE(keypath);
return rc;
}
static int virCgroupSetValueU64(virCgroupPtr group,
int controller,
const char *key,
unsigned long long int value)
{
char *strval = NULL;
int rc;
if (virAsprintf(&strval, "%llu", value) == -1)
return -ENOMEM;
rc = virCgroupSetValueStr(group, controller, key, strval);
VIR_FREE(strval);
return rc;
}
static int virCgroupSetValueI64(virCgroupPtr group,
int controller,
const char *key,
long long int value)
{
char *strval = NULL;
int rc;
if (virAsprintf(&strval, "%lld", value) == -1)
return -ENOMEM;
rc = virCgroupSetValueStr(group, controller, key, strval);
VIR_FREE(strval);
return rc;
}
static int virCgroupGetValueI64(virCgroupPtr group,
int controller,
const char *key,
long long int *value)
{
char *strval = NULL;
int rc = 0;
rc = virCgroupGetValueStr(group, controller, key, &strval);
if (rc != 0)
goto out;
if (virStrToLong_ll(strval, NULL, 10, value) < 0)
rc = -EINVAL;
out:
VIR_FREE(strval);
return rc;
}
static int virCgroupGetValueU64(virCgroupPtr group,
int controller,
const char *key,
unsigned long long int *value)
{
char *strval = NULL;
int rc = 0;
rc = virCgroupGetValueStr(group, controller, key, &strval);
if (rc != 0)
goto out;
if (virStrToLong_ull(strval, NULL, 10, value) < 0)
rc = -EINVAL;
out:
VIR_FREE(strval);
return rc;
}
#if defined HAVE_MNTENT_H && defined HAVE_GETMNTENT_R
static int virCgroupCpuSetInherit(virCgroupPtr parent, virCgroupPtr group)
{
int i;
int rc = 0;
const char *inherit_values[] = {
"cpuset.cpus",
"cpuset.mems",
};
VIR_DEBUG("Setting up inheritance %s -> %s", parent->path, group->path);
for (i = 0; i < ARRAY_CARDINALITY(inherit_values) ; i++) {
char *value;
rc = virCgroupGetValueStr(parent,
VIR_CGROUP_CONTROLLER_CPUSET,
inherit_values[i],
&value);
if (rc != 0) {
VIR_ERROR(_("Failed to get %s %d"), inherit_values[i], rc);
break;
}
VIR_DEBUG("Inherit %s = %s", inherit_values[i], value);
rc = virCgroupSetValueStr(group,
VIR_CGROUP_CONTROLLER_CPUSET,
inherit_values[i],
value);
VIR_FREE(value);
if (rc != 0) {
VIR_ERROR(_("Failed to set %s %d"), inherit_values[i], rc);
break;
}
}
return rc;
}
static int virCgroupSetMemoryUseHierarchy(virCgroupPtr group)
{
int rc = 0;
unsigned long long value;
const char *filename = "memory.use_hierarchy";
rc = virCgroupGetValueU64(group,
VIR_CGROUP_CONTROLLER_MEMORY,
filename, &value);
if (rc != 0) {
VIR_ERROR(_("Failed to read %s/%s (%d)"), group->path, filename, rc);
return rc;
}
/* Setting twice causes error, so if already enabled, skip setting */
if (value == 1)
return 0;
VIR_DEBUG("Setting up %s/%s", group->path, filename);
rc = virCgroupSetValueU64(group,
VIR_CGROUP_CONTROLLER_MEMORY,
filename, 1);
if (rc != 0) {
VIR_ERROR(_("Failed to set %s/%s (%d)"), group->path, filename, rc);
}
return rc;
}
static int virCgroupMakeGroup(virCgroupPtr parent, virCgroupPtr group,
int create, unsigned int flags)
{
int i;
int rc = 0;
VIR_DEBUG("Make group %s", group->path);
for (i = 0 ; i < VIR_CGROUP_CONTROLLER_LAST ; i++) {
char *path = NULL;
/* Skip over controllers that aren't mounted */
if (!group->controllers[i].mountPoint)
continue;
/* We need to control cpu bandwidth for each vcpu now */
if ((flags & VIR_CGROUP_VCPU) && (i != VIR_CGROUP_CONTROLLER_CPU)) {
/* treat it as unmounted and we can use virCgroupAddTask */
VIR_FREE(group->controllers[i].mountPoint);
continue;
}
rc = virCgroupPathOfController(group, i, "", &path);
if (rc < 0)
return rc;
/* As of Feb 2011, clang can't see that the above function
* call did not modify group. */
sa_assert(group->controllers[i].mountPoint);
VIR_DEBUG("Make controller %s", path);
if (access(path, F_OK) != 0) {
if (!create ||
mkdir(path, 0755) < 0) {
/* With a kernel that doesn't support multi-level directory
* for blkio controller, libvirt will fail and disable all
* other controllers even though they are available. So
* treat blkio as unmounted if mkdir fails. */
if (i == VIR_CGROUP_CONTROLLER_BLKIO) {
rc = 0;
VIR_FREE(group->controllers[i].mountPoint);
VIR_FREE(path);
continue;
} else {
rc = -errno;
VIR_FREE(path);
break;
}
}
if (group->controllers[VIR_CGROUP_CONTROLLER_CPUSET].mountPoint != NULL &&
(i == VIR_CGROUP_CONTROLLER_CPUSET ||
STREQ(group->controllers[i].mountPoint, group->controllers[VIR_CGROUP_CONTROLLER_CPUSET].mountPoint))) {
rc = virCgroupCpuSetInherit(parent, group);
if (rc != 0) {
VIR_FREE(path);
break;
}
}
/*
* Note that virCgroupSetMemoryUseHierarchy should always be
* called prior to creating subcgroups and attaching tasks.
*/
if ((flags & VIR_CGROUP_MEM_HIERACHY) &&
(group->controllers[VIR_CGROUP_CONTROLLER_MEMORY].mountPoint != NULL) &&
(i == VIR_CGROUP_CONTROLLER_MEMORY ||
STREQ(group->controllers[i].mountPoint, group->controllers[VIR_CGROUP_CONTROLLER_MEMORY].mountPoint))) {
rc = virCgroupSetMemoryUseHierarchy(group);
if (rc != 0) {
VIR_FREE(path);
break;
}
}
}
VIR_FREE(path);
}
return rc;
}
static int virCgroupNew(const char *path,
virCgroupPtr *group)
{
int rc = 0;
char *typpath = NULL;
VIR_DEBUG("New group %s", path);
*group = NULL;
if (VIR_ALLOC((*group)) != 0) {
rc = -ENOMEM;
goto err;
}
if (!((*group)->path = strdup(path))) {
rc = -ENOMEM;
goto err;
}
rc = virCgroupDetect(*group);
if (rc < 0)
goto err;
return rc;
err:
virCgroupFree(group);
*group = NULL;
VIR_FREE(typpath);
return rc;
}
static int virCgroupAppRoot(int privileged,
virCgroupPtr *group,
int create)
{
virCgroupPtr rootgrp = NULL;
int rc;
rc = virCgroupNew("/", &rootgrp);
if (rc != 0)
return rc;
if (privileged) {
rc = virCgroupNew("/libvirt", group);
} else {
char *rootname;
char *username;
username = virGetUserName(getuid());
if (!username) {
rc = -ENOMEM;
goto cleanup;
}
rc = virAsprintf(&rootname, "/libvirt-%s", username);
VIR_FREE(username);
if (rc < 0) {
rc = -ENOMEM;
goto cleanup;
}
rc = virCgroupNew(rootname, group);
VIR_FREE(rootname);
}
if (rc != 0)
goto cleanup;
rc = virCgroupMakeGroup(rootgrp, *group, create, VIR_CGROUP_NONE);
cleanup:
virCgroupFree(&rootgrp);
return rc;
}
#endif
#if defined _DIRENT_HAVE_D_TYPE
static int virCgroupRemoveRecursively(char *grppath)
{
DIR *grpdir;
struct dirent *ent;
int rc = 0;
grpdir = opendir(grppath);
if (grpdir == NULL) {
if (errno == ENOENT)
return 0;
rc = -errno;
VIR_ERROR(_("Unable to open %s (%d)"), grppath, errno);
return rc;
}
for (;;) {
char *path;
errno = 0;
ent = readdir(grpdir);
if (ent == NULL) {
if ((rc = -errno))
VIR_ERROR(_("Failed to readdir for %s (%d)"), grppath, errno);
break;
}
if (ent->d_name[0] == '.') continue;
if (ent->d_type != DT_DIR) continue;
if (virAsprintf(&path, "%s/%s", grppath, ent->d_name) == -1) {
rc = -ENOMEM;
break;
}
rc = virCgroupRemoveRecursively(path);
VIR_FREE(path);
if (rc != 0)
break;
}
closedir(grpdir);
VIR_DEBUG("Removing cgroup %s", grppath);
if (rmdir(grppath) != 0 && errno != ENOENT) {
rc = -errno;
VIR_ERROR(_("Unable to remove %s (%d)"), grppath, errno);
}
return rc;
}
#else
static int virCgroupRemoveRecursively(char *grppath ATTRIBUTE_UNUSED)
{
/* Claim no support */
return -ENXIO;
}
#endif
/**
* virCgroupRemove:
*
* @group: The group to be removed
*
* It first removes all child groups recursively
* in depth first order and then removes @group
* because the presence of the child groups
* prevents removing @group.
*
* Returns: 0 on success
*/
int virCgroupRemove(virCgroupPtr group)
{
int rc = 0;
int i;
char *grppath = NULL;
for (i = 0 ; i < VIR_CGROUP_CONTROLLER_LAST ; i++) {
/* Skip over controllers not mounted */
if (!group->controllers[i].mountPoint)
continue;
if (virCgroupPathOfController(group,
i,
NULL,
&grppath) != 0)
continue;
VIR_DEBUG("Removing cgroup %s and all child cgroups", grppath);
rc = virCgroupRemoveRecursively(grppath);
VIR_FREE(grppath);
}
return rc;
}
/**
* virCgroupAddTask:
*
* @group: The cgroup to add a task to
* @pid: The pid of the task to add
*
* Returns: 0 on success
*/
int virCgroupAddTask(virCgroupPtr group, pid_t pid)
{
int rc = 0;
int i;
for (i = 0 ; i < VIR_CGROUP_CONTROLLER_LAST ; i++) {
/* Skip over controllers not mounted */
if (!group->controllers[i].mountPoint)
continue;
rc = virCgroupSetValueU64(group, i, "tasks", (unsigned long long)pid);
if (rc != 0)
break;
}
return rc;
}
/**
* virCgroupForDriver:
*
* @name: name of this driver (e.g., xen, qemu, lxc)
* @group: Pointer to returned virCgroupPtr
*
* Returns 0 on success
*/
#if defined HAVE_MNTENT_H && defined HAVE_GETMNTENT_R
int virCgroupForDriver(const char *name,
virCgroupPtr *group,
int privileged,
int create)
{
int rc;
char *path = NULL;
virCgroupPtr rootgrp = NULL;
rc = virCgroupAppRoot(privileged, &rootgrp, create);
if (rc != 0)
goto out;
if (virAsprintf(&path, "%s/%s", rootgrp->path, name) < 0) {
rc = -ENOMEM;
goto out;
}
rc = virCgroupNew(path, group);
VIR_FREE(path);
if (rc == 0) {
rc = virCgroupMakeGroup(rootgrp, *group, create, VIR_CGROUP_NONE);
if (rc != 0)
virCgroupFree(group);
}
out:
virCgroupFree(&rootgrp);
return rc;
}
#else
int virCgroupForDriver(const char *name ATTRIBUTE_UNUSED,
virCgroupPtr *group ATTRIBUTE_UNUSED,
int privileged ATTRIBUTE_UNUSED,
int create ATTRIBUTE_UNUSED)
{
/* Claim no support */
return -ENXIO;
}
#endif
/**
* virCgroupForDomain:
*
* @driver: group for driver owning the domain
* @name: name of the domain
* @group: Pointer to returned virCgroupPtr
*
* Returns 0 on success
*/
#if defined HAVE_MNTENT_H && defined HAVE_GETMNTENT_R
int virCgroupForDomain(virCgroupPtr driver,
const char *name,
virCgroupPtr *group,
int create)
{
int rc;
char *path;
if (driver == NULL)
return -EINVAL;
if (virAsprintf(&path, "%s/%s", driver->path, name) < 0)
return -ENOMEM;
rc = virCgroupNew(path, group);
VIR_FREE(path);
if (rc == 0) {
/*
* Create a cgroup with memory.use_hierarchy enabled to
* surely account memory usage of lxc with ns subsystem
* enabled. (To be exact, memory and ns subsystems are
* enabled at the same time.)
*
* The reason why doing it here, not a upper group, say
* a group for driver, is to avoid overhead to track
* cumulative usage that we don't need.
*/
rc = virCgroupMakeGroup(driver, *group, create, VIR_CGROUP_MEM_HIERACHY);
if (rc != 0)
virCgroupFree(group);
}
return rc;
}
#else
int virCgroupForDomain(virCgroupPtr driver ATTRIBUTE_UNUSED,
const char *name ATTRIBUTE_UNUSED,
virCgroupPtr *group ATTRIBUTE_UNUSED,
int create ATTRIBUTE_UNUSED)
{
return -ENXIO;
}
#endif
/**
* virCgroupForVcpu:
*
* @driver: group for the domain
* @vcpuid: id of the vcpu
* @group: Pointer to returned virCgroupPtr
*
* Returns 0 on success
*/
#if defined HAVE_MNTENT_H && defined HAVE_GETMNTENT_R
int virCgroupForVcpu(virCgroupPtr driver,
int vcpuid,
virCgroupPtr *group,
int create)
{
int rc;
char *path;
if (driver == NULL)
return -EINVAL;
if (virAsprintf(&path, "%s/vcpu%d", driver->path, vcpuid) < 0)
return -ENOMEM;
rc = virCgroupNew(path, group);
VIR_FREE(path);
if (rc == 0) {
rc = virCgroupMakeGroup(driver, *group, create, VIR_CGROUP_VCPU);
if (rc != 0)
virCgroupFree(group);
}
return rc;
}
#else
int virCgroupForVcpu(virCgroupPtr driver ATTRIBUTE_UNUSED,
int vcpuid ATTRIBUTE_UNUSED,
virCgroupPtr *group ATTRIBUTE_UNUSED,
int create ATTRIBUTE_UNUSED)
{
return -ENXIO;
}
#endif
/**
* virCgroupSetBlkioWeight:
*
* @group: The cgroup to change io weight for
* @weight: The Weight for this cgroup
*
* Returns: 0 on success
*/
int virCgroupSetBlkioWeight(virCgroupPtr group, unsigned int weight)
{
if (weight > 1000 || weight < 100)
return -EINVAL;
return virCgroupSetValueU64(group,
VIR_CGROUP_CONTROLLER_BLKIO,
"blkio.weight",
weight);
}
/**
* virCgroupGetBlkioWeight:
*
* @group: The cgroup to get weight for
* @Weight: Pointer to returned weight
*
* Returns: 0 on success
*/
int virCgroupGetBlkioWeight(virCgroupPtr group, unsigned int *weight)
{
unsigned long long tmp;
int ret;
ret = virCgroupGetValueU64(group,
VIR_CGROUP_CONTROLLER_BLKIO,
"blkio.weight", &tmp);
if (ret == 0)
*weight = tmp;
return ret;
}
/**
* virCgroupSetMemory:
*
* @group: The cgroup to change memory for
* @kb: The memory amount in kilobytes
*
* Returns: 0 on success
*/
int virCgroupSetMemory(virCgroupPtr group, unsigned long long kb)
{
unsigned long long maxkb = VIR_DOMAIN_MEMORY_PARAM_UNLIMITED;
if (kb > maxkb)
return -EINVAL;
else if (kb == maxkb)
return virCgroupSetValueI64(group,
VIR_CGROUP_CONTROLLER_MEMORY,
"memory.limit_in_bytes",
-1);
else
return virCgroupSetValueU64(group,
VIR_CGROUP_CONTROLLER_MEMORY,
"memory.limit_in_bytes",
kb << 10);
}
/**
* virCgroupGetMemoryUsage:
*
* @group: The cgroup to change memory for
* @kb: Pointer to returned used memory in kilobytes
*
* Returns: 0 on success
*/
int virCgroupGetMemoryUsage(virCgroupPtr group, unsigned long *kb)
{
long long unsigned int usage_in_bytes;
int ret;
ret = virCgroupGetValueU64(group,
VIR_CGROUP_CONTROLLER_MEMORY,
"memory.usage_in_bytes", &usage_in_bytes);
if (ret == 0)
*kb = (unsigned long) usage_in_bytes >> 10;
return ret;
}
/**
* virCgroupSetMemoryHardLimit:
*
* @group: The cgroup to change memory hard limit for
* @kb: The memory amount in kilobytes
*
* Returns: 0 on success
*/
int virCgroupSetMemoryHardLimit(virCgroupPtr group, unsigned long long kb)
{
return virCgroupSetMemory(group, kb);
}
/**
* virCgroupGetMemoryHardLimit:
*
* @group: The cgroup to get the memory hard limit for
* @kb: The memory amount in kilobytes
*
* Returns: 0 on success
*/
int virCgroupGetMemoryHardLimit(virCgroupPtr group, unsigned long long *kb)
{
long long unsigned int limit_in_bytes;
int ret;
ret = virCgroupGetValueU64(group,
VIR_CGROUP_CONTROLLER_MEMORY,
"memory.limit_in_bytes", &limit_in_bytes);
if (ret == 0)
*kb = limit_in_bytes >> 10;
return ret;
}
/**
* virCgroupSetMemorySoftLimit:
*
* @group: The cgroup to change memory soft limit for
* @kb: The memory amount in kilobytes
*
* Returns: 0 on success
*/
int virCgroupSetMemorySoftLimit(virCgroupPtr group, unsigned long long kb)
{
unsigned long long maxkb = VIR_DOMAIN_MEMORY_PARAM_UNLIMITED;
if (kb > maxkb)
return -EINVAL;
else if (kb == maxkb)
return virCgroupSetValueI64(group,
VIR_CGROUP_CONTROLLER_MEMORY,
"memory.soft_limit_in_bytes",
-1);
else
return virCgroupSetValueU64(group,
VIR_CGROUP_CONTROLLER_MEMORY,
"memory.soft_limit_in_bytes",
kb << 10);
}
/**
* virCgroupGetMemorySoftLimit:
*
* @group: The cgroup to get the memory soft limit for
* @kb: The memory amount in kilobytes
*
* Returns: 0 on success
*/
int virCgroupGetMemorySoftLimit(virCgroupPtr group, unsigned long long *kb)
{
long long unsigned int limit_in_bytes;
int ret;
ret = virCgroupGetValueU64(group,
VIR_CGROUP_CONTROLLER_MEMORY,
"memory.soft_limit_in_bytes", &limit_in_bytes);
if (ret == 0)
*kb = limit_in_bytes >> 10;
return ret;
}
/**
* virCgroupSetMemSwapHardLimit:
*
* @group: The cgroup to change mem+swap hard limit for
* @kb: The mem+swap amount in kilobytes
*
* Returns: 0 on success
*/
int virCgroupSetMemSwapHardLimit(virCgroupPtr group, unsigned long long kb)
{
unsigned long long maxkb = VIR_DOMAIN_MEMORY_PARAM_UNLIMITED;
if (kb > maxkb)
return -EINVAL;
else if (kb == maxkb)
return virCgroupSetValueI64(group,
VIR_CGROUP_CONTROLLER_MEMORY,
"memory.memsw.limit_in_bytes",
-1);
else
return virCgroupSetValueU64(group,
VIR_CGROUP_CONTROLLER_MEMORY,
"memory.memsw.limit_in_bytes",
kb << 10);
}
/**
* virCgroupGetMemSwapHardLimit:
*
* @group: The cgroup to get mem+swap hard limit for
* @kb: The mem+swap amount in kilobytes
*
* Returns: 0 on success
*/
int virCgroupGetMemSwapHardLimit(virCgroupPtr group, unsigned long long *kb)
{
long long unsigned int limit_in_bytes;
int ret;
ret = virCgroupGetValueU64(group,
VIR_CGROUP_CONTROLLER_MEMORY,
"memory.memsw.limit_in_bytes", &limit_in_bytes);
if (ret == 0)
*kb = limit_in_bytes >> 10;
return ret;
}
/**
* virCgroupDenyAllDevices:
*
* @group: The cgroup to deny all permissions, for all devices
*
* Returns: 0 on success
*/
int virCgroupDenyAllDevices(virCgroupPtr group)
{
return virCgroupSetValueStr(group,
VIR_CGROUP_CONTROLLER_DEVICES,
"devices.deny",
"a");
}
/**
* virCgroupAllowDevice:
*
* @group: The cgroup to allow a device for
* @type: The device type (i.e., 'c' or 'b')
* @major: The major number of the device
* @minor: The minor number of the device
* @perms: Bitwise or of VIR_CGROUP_DEVICE permission bits to allow
*
* Returns: 0 on success
*/
int virCgroupAllowDevice(virCgroupPtr group, char type, int major, int minor,
int perms)
{
int rc;
char *devstr = NULL;
if (virAsprintf(&devstr, "%c %i:%i %s%s%s", type, major, minor,
perms & VIR_CGROUP_DEVICE_READ ? "r" : "",
perms & VIR_CGROUP_DEVICE_WRITE ? "w" : "",
perms & VIR_CGROUP_DEVICE_MKNOD ? "m" : "") == -1) {
rc = -ENOMEM;
goto out;
}
rc = virCgroupSetValueStr(group,
VIR_CGROUP_CONTROLLER_DEVICES,
"devices.allow",
devstr);
out:
VIR_FREE(devstr);
return rc;
}
/**
* virCgroupAllowDeviceMajor:
*
* @group: The cgroup to allow an entire device major type for
* @type: The device type (i.e., 'c' or 'b')
* @major: The major number of the device type
* @perms: Bitwise or of VIR_CGROUP_DEVICE permission bits to allow
*
* Returns: 0 on success
*/
int virCgroupAllowDeviceMajor(virCgroupPtr group, char type, int major,
int perms)
{
int rc;
char *devstr = NULL;
if (virAsprintf(&devstr, "%c %i:* %s%s%s", type, major,
perms & VIR_CGROUP_DEVICE_READ ? "r" : "",
perms & VIR_CGROUP_DEVICE_WRITE ? "w" : "",
perms & VIR_CGROUP_DEVICE_MKNOD ? "m" : "") == -1) {
rc = -ENOMEM;
goto out;
}
rc = virCgroupSetValueStr(group,
VIR_CGROUP_CONTROLLER_DEVICES,
"devices.allow",
devstr);
out:
VIR_FREE(devstr);
return rc;
}
/**
* virCgroupAllowDevicePath:
*
* @group: The cgroup to allow the device for
* @path: the device to allow
* @perms: Bitwise or of VIR_CGROUP_DEVICE permission bits to allow
*
* Queries the type of device and its major/minor number, and
* adds that to the cgroup ACL
*
* Returns: 0 on success, 1 if path exists but is not a device, or
* negative errno value on failure
*/
#if defined(major) && defined(minor)
int virCgroupAllowDevicePath(virCgroupPtr group, const char *path, int perms)
{
struct stat sb;
if (stat(path, &sb) < 0)
return -errno;
if (!S_ISCHR(sb.st_mode) && !S_ISBLK(sb.st_mode))
return 1;
return virCgroupAllowDevice(group,
S_ISCHR(sb.st_mode) ? 'c' : 'b',
major(sb.st_rdev),
minor(sb.st_rdev),
perms);
}
#else
int virCgroupAllowDevicePath(virCgroupPtr group ATTRIBUTE_UNUSED,
const char *path ATTRIBUTE_UNUSED,
int perms ATTRIBUTE_UNUSED)
{
return -ENOSYS;
}
#endif
/**
* virCgroupDenyDevice:
*
* @group: The cgroup to deny a device for
* @type: The device type (i.e., 'c' or 'b')
* @major: The major number of the device
* @minor: The minor number of the device
* @perms: Bitwise or of VIR_CGROUP_DEVICE permission bits to deny
*
* Returns: 0 on success
*/
int virCgroupDenyDevice(virCgroupPtr group, char type, int major, int minor,
int perms)
{
int rc;
char *devstr = NULL;
if (virAsprintf(&devstr, "%c %i:%i %s%s%s", type, major, minor,
perms & VIR_CGROUP_DEVICE_READ ? "r" : "",
perms & VIR_CGROUP_DEVICE_WRITE ? "w" : "",
perms & VIR_CGROUP_DEVICE_MKNOD ? "m" : "") == -1) {
rc = -ENOMEM;
goto out;
}
rc = virCgroupSetValueStr(group,
VIR_CGROUP_CONTROLLER_DEVICES,
"devices.deny",
devstr);
out:
VIR_FREE(devstr);
return rc;
}
/**
* virCgroupDenyDeviceMajor:
*
* @group: The cgroup to deny an entire device major type for
* @type: The device type (i.e., 'c' or 'b')
* @major: The major number of the device type
* @perms: Bitwise or of VIR_CGROUP_DEVICE permission bits to deny
*
* Returns: 0 on success
*/
int virCgroupDenyDeviceMajor(virCgroupPtr group, char type, int major,
int perms)
{
int rc;
char *devstr = NULL;
if (virAsprintf(&devstr, "%c %i:* %s%s%s", type, major,
perms & VIR_CGROUP_DEVICE_READ ? "r" : "",
perms & VIR_CGROUP_DEVICE_WRITE ? "w" : "",
perms & VIR_CGROUP_DEVICE_MKNOD ? "m" : "") == -1) {
rc = -ENOMEM;
goto out;
}
rc = virCgroupSetValueStr(group,
VIR_CGROUP_CONTROLLER_DEVICES,
"devices.deny",
devstr);
out:
VIR_FREE(devstr);
return rc;
}
#if defined(major) && defined(minor)
int virCgroupDenyDevicePath(virCgroupPtr group, const char *path, int perms)
{
struct stat sb;
if (stat(path, &sb) < 0)
return -errno;
if (!S_ISCHR(sb.st_mode) && !S_ISBLK(sb.st_mode))
return 1;
return virCgroupDenyDevice(group,
S_ISCHR(sb.st_mode) ? 'c' : 'b',
major(sb.st_rdev),
minor(sb.st_rdev),
perms);
}
#else
int virCgroupDenyDevicePath(virCgroupPtr group ATTRIBUTE_UNUSED,
const char *path ATTRIBUTE_UNUSED,
int perms ATTRIBUTE_UNUSED)
{
return -ENOSYS;
}
#endif
int virCgroupSetCpuShares(virCgroupPtr group, unsigned long long shares)
{
return virCgroupSetValueU64(group,
VIR_CGROUP_CONTROLLER_CPU,
"cpu.shares", shares);
}
int virCgroupGetCpuShares(virCgroupPtr group, unsigned long long *shares)
{
return virCgroupGetValueU64(group,
VIR_CGROUP_CONTROLLER_CPU,
"cpu.shares", shares);
}
/**
* virCgroupSetCpuCfsPeriod:
*
* @group: The cgroup to change cpu.cfs_period_us for
* @cfs_period: The bandwidth period in usecs
*
* Returns: 0 on success
*/
int virCgroupSetCpuCfsPeriod(virCgroupPtr group, unsigned long long cfs_period)
{
/* The cfs_period shoule be greater or equal than 1ms, and less or equal
* than 1s.
*/
if (cfs_period < 1000 || cfs_period > 1000000)
return -EINVAL;
return virCgroupSetValueU64(group,
VIR_CGROUP_CONTROLLER_CPU,
"cpu.cfs_period_us", cfs_period);
}
/**
* virCgroupGetCpuCfsPeriod:
*
* @group: The cgroup to get cpu.cfs_period_us for
* @cfs_period: Pointer to the returned bandwidth period in usecs
*
* Returns: 0 on success
*/
int virCgroupGetCpuCfsPeriod(virCgroupPtr group, unsigned long long *cfs_period)
{
return virCgroupGetValueU64(group,
VIR_CGROUP_CONTROLLER_CPU,
"cpu.cfs_period_us", cfs_period);
}
/**
* virCgroupSetCpuCfsQuota:
*
* @group: The cgroup to change cpu.cfs_quota_us for
* @cfs_quota: the cpu bandwidth (in usecs) that this tg will be allowed to
* consume over period
*
* Returns: 0 on success
*/
int virCgroupSetCpuCfsQuota(virCgroupPtr group, long long cfs_quota)
{
if (cfs_quota >= 0) {
/* The cfs_quota shoule be greater or equal than 1ms */
if (cfs_quota < 1000)
return -EINVAL;
/* check overflow */
if (cfs_quota > ULLONG_MAX / 1000)
return -EINVAL;
}
return virCgroupSetValueI64(group,
VIR_CGROUP_CONTROLLER_CPU,
"cpu.cfs_quota_us", cfs_quota);
}
/**
* virCgroupGetCpuCfsQuota:
*
* @group: The cgroup to get cpu.cfs_quota_us for
* @cfs_quota: Pointer to the returned cpu bandwidth (in usecs) that this tg
* will be allowed to consume over period
*
* Returns: 0 on success
*/
int virCgroupGetCpuCfsQuota(virCgroupPtr group, long long *cfs_quota)
{
return virCgroupGetValueI64(group,
VIR_CGROUP_CONTROLLER_CPU,
"cpu.cfs_quota_us", cfs_quota);
}
int virCgroupGetCpuacctUsage(virCgroupPtr group, unsigned long long *usage)
{
return virCgroupGetValueU64(group,
VIR_CGROUP_CONTROLLER_CPUACCT,
"cpuacct.usage", usage);
}
int virCgroupSetFreezerState(virCgroupPtr group, const char *state)
{
return virCgroupSetValueStr(group,
VIR_CGROUP_CONTROLLER_CPU,
"freezer.state", state);
}
int virCgroupGetFreezerState(virCgroupPtr group, char **state)
{
return virCgroupGetValueStr(group,
VIR_CGROUP_CONTROLLER_CPU,
"freezer.state", state);
}
#if defined HAVE_KILL && defined HAVE_MNTENT_H && defined HAVE_GETMNTENT_R
static int virCgroupKillInternal(virCgroupPtr group, int signum, virHashTablePtr pids)
{
int rc;
int killedAny = 0;
char *keypath = NULL;
bool done = false;
FILE *fp = NULL;
VIR_DEBUG("group=%p path=%s signum=%d pids=%p",
group, group->path, signum, pids);
rc = virCgroupPathOfController(group, -1, "tasks", &keypath);
if (rc != 0) {
VIR_DEBUG("No path of %s, tasks", group->path);
return rc;
}
/* PIDs may be forking as we kill them, so loop
* until there are no new PIDs found
*/
while (!done) {
done = true;
if (!(fp = fopen(keypath, "r"))) {
rc = -errno;
VIR_DEBUG("Failed to read %s: %m\n", keypath);
goto cleanup;
} else {
while (!feof(fp)) {
unsigned long pid;
if (fscanf(fp, "%lu", &pid) != 1) {
if (feof(fp))
break;
rc = -errno;
VIR_DEBUG("Failed to read %s: %m\n", keypath);
goto cleanup;
}
if (virHashLookup(pids, (void*)pid))
continue;
VIR_DEBUG("pid=%lu", pid);
if (kill((pid_t)pid, signum) < 0) {
if (errno != ESRCH) {
rc = -errno;
goto cleanup;
}
/* Leave RC == 0 since we didn't kill one */
} else {
killedAny = 1;
done = false;
}
ignore_value(virHashAddEntry(pids, (void*)pid, (void*)1));
}
VIR_FORCE_FCLOSE(fp);
}
}
rc = killedAny ? 1 : 0;
cleanup:
VIR_FREE(keypath);
VIR_FORCE_FCLOSE(fp);
return rc;
}
static unsigned long virCgroupPidCode(const void *name)
{
return (unsigned long)name;
}
static bool virCgroupPidEqual(const void *namea, const void *nameb)
{
return namea == nameb;
}
static void *virCgroupPidCopy(const void *name)
{
return (void*)name;
}
/*
* Returns
* < 0 : errno that occurred
* 0 : no PIDs killed
* 1 : at least one PID killed
*/
int virCgroupKill(virCgroupPtr group, int signum)
{
VIR_DEBUG("group=%p path=%s signum=%d", group, group->path, signum);
int rc;
/* The 'tasks' file in cgroups can contain duplicated
* pids, so we use a hash to track which we've already
* killed.
*/
virHashTablePtr pids = virHashCreateFull(100,
NULL,
virCgroupPidCode,
virCgroupPidEqual,
virCgroupPidCopy,
NULL);
rc = virCgroupKillInternal(group, signum, pids);
virHashFree(pids);
return rc;
}
static int virCgroupKillRecursiveInternal(virCgroupPtr group, int signum, virHashTablePtr pids, bool dormdir)
{
int rc;
int killedAny = 0;
char *keypath = NULL;
DIR *dp;
virCgroupPtr subgroup = NULL;
struct dirent *ent;
VIR_DEBUG("group=%p path=%s signum=%d pids=%p", group, group->path, signum, pids);
rc = virCgroupPathOfController(group, -1, "", &keypath);
if (rc != 0) {
VIR_DEBUG("No path of %s, tasks", group->path);
return rc;
}
if ((rc = virCgroupKillInternal(group, signum, pids)) != 0)
return rc;
VIR_DEBUG("Iterate over children of %s", keypath);
if (!(dp = opendir(keypath))) {
rc = -errno;
return rc;
}
while ((ent = readdir(dp))) {
char *subpath;
if (STREQ(ent->d_name, "."))
continue;
if (STREQ(ent->d_name, ".."))
continue;
if (ent->d_type != DT_DIR)
continue;
VIR_DEBUG("Process subdir %s", ent->d_name);
if (virAsprintf(&subpath, "%s/%s", group->path, ent->d_name) < 0) {
rc = -ENOMEM;
goto cleanup;
}
if ((rc = virCgroupNew(subpath, &subgroup)) != 0)
goto cleanup;
if ((rc = virCgroupKillRecursiveInternal(subgroup, signum, pids, true)) < 0)
goto cleanup;
if (rc == 1)
killedAny = 1;
if (dormdir)
virCgroupRemove(subgroup);
virCgroupFree(&subgroup);
}
rc = killedAny;
cleanup:
virCgroupFree(&subgroup);
closedir(dp);
return rc;
}
int virCgroupKillRecursive(virCgroupPtr group, int signum)
{
int rc;
VIR_DEBUG("group=%p path=%s signum=%d", group, group->path, signum);
virHashTablePtr pids = virHashCreateFull(100,
NULL,
virCgroupPidCode,
virCgroupPidEqual,
virCgroupPidCopy,
NULL);
rc = virCgroupKillRecursiveInternal(group, signum, pids, false);
virHashFree(pids);
return rc;
}
int virCgroupKillPainfully(virCgroupPtr group)
{
int i;
int rc;
VIR_DEBUG("cgroup=%p path=%s", group, group->path);
for (i = 0 ; i < 15 ; i++) {
int signum;
if (i == 0)
signum = SIGTERM;
else if (i == 8)
signum = SIGKILL;
else
signum = 0; /* Just check for existance */
rc = virCgroupKillRecursive(group, signum);
VIR_DEBUG("Iteration %d rc=%d", i, rc);
/* If rc == -1 we hit error, if 0 we ran out of PIDs */
if (rc <= 0)
break;
usleep(200 * 1000);
}
VIR_DEBUG("Complete %d", rc);
return rc;
}
#else /* !(HAVE_KILL, HAVE_MNTENT_H, HAVE_GETMNTENT_R) */
int virCgroupKill(virCgroupPtr group ATTRIBUTE_UNUSED,
int signum ATTRIBUTE_UNUSED)
{
return -ENOSYS;
}
int virCgroupKillRecursive(virCgroupPtr group ATTRIBUTE_UNUSED,
int signum ATTRIBUTE_UNUSED)
{
return -ENOSYS;
}
int virCgroupKillPainfully(virCgroupPtr group ATTRIBUTE_UNUSED)
{
return -ENOSYS;
}
#endif /* HAVE_KILL, HAVE_MNTENT_H, HAVE_GETMNTENT_R */