External/libvirt
1
0
Fork 0
mirror of https://gitlab.com/libvirt/libvirt.git synced 2024-11-01 10:51:12 +00:00
Code Issues Packages Projects Releases Wiki Activity
cc34260f5a
libvirt/src/util/virhostcpu.c
Jiri Denemark f0f6faba63 util: Add virHostCPUGetTscInfo 
On a KVM x86_64 host which supports invariant TSC this function can be
used to detect the TSC frequency and the availability of TSC scaling.

The magic MSR numbers required to check if VMX scaling is supported on
the host are documented in Volume 3 of the Intel® 64 and IA-32
Architectures Software Developer’s Manual.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2019-06-03 18:07:16 +02:00

1412 lines
39 KiB
C
Raw Blame History

/*
* virhostcpu.c: helper APIs for host CPU info
*
* Copyright (C) 2006-2016 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/>.
*/
#include <config.h>
#include <dirent.h>
#include <sys/utsname.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <unistd.h>
#if HAVE_LINUX_KVM_H
# include <linux/kvm.h>
#endif
#if defined(__FreeBSD__) || defined(__APPLE__)
# include <sys/time.h>
# include <sys/types.h>
# include <sys/sysctl.h>
# include <sys/resource.h>
#endif
#include "c-ctype.h"
#include "viralloc.h"
#define LIBVIRT_VIRHOSTCPUPRIV_H_ALLOW
#include "virhostcpupriv.h"
#include "physmem.h"
#include "virerror.h"
#include "count-one-bits.h"
#include "intprops.h"
#include "virarch.h"
#include "virfile.h"
#include "virtypedparam.h"
#include "virstring.h"
#include "virnuma.h"
#include "virlog.h"
#define VIR_FROM_THIS VIR_FROM_NONE
VIR_LOG_INIT("util.hostcpu");
#define KVM_DEVICE "/dev/kvm"
#define MSR_DEVICE "/dev/cpu/0/msr"
#if defined(__FreeBSD__) || defined(__APPLE__)
static int
virHostCPUGetCountAppleFreeBSD(void)
{
int ncpu_mib[2] = { CTL_HW, HW_NCPU };
unsigned long ncpu;
size_t ncpu_len = sizeof(ncpu);
if (sysctl(ncpu_mib, 2, &ncpu, &ncpu_len, NULL, 0) == -1) {
virReportSystemError(errno, "%s", _("Cannot obtain CPU count"));
return -1;
}
return ncpu;
}
#endif /* defined(__FreeBSD__) || defined(__APPLE__) */
#ifdef __FreeBSD__
# define BSD_CPU_STATS_ALL 4
# define BSD_MEMORY_STATS_ALL 4
# define TICK_TO_NSEC (1000ull * 1000ull * 1000ull / (stathz ? stathz : hz))
static int
virHostCPUGetStatsFreeBSD(int cpuNum,
virNodeCPUStatsPtr params,
int *nparams)
{
const char *sysctl_name;
long *cpu_times;
struct clockinfo clkinfo;
size_t i, j, cpu_times_size, clkinfo_size;
int cpu_times_num, offset, hz, stathz, ret = -1;
struct field_cpu_map {
const char *field;
int idx[CPUSTATES];
} cpu_map[] = {
{VIR_NODE_CPU_STATS_KERNEL, {CP_SYS}},
{VIR_NODE_CPU_STATS_USER, {CP_USER, CP_NICE}},
{VIR_NODE_CPU_STATS_IDLE, {CP_IDLE}},
{VIR_NODE_CPU_STATS_INTR, {CP_INTR}},
{NULL, {0}}
};
if ((*nparams) == 0) {
*nparams = BSD_CPU_STATS_ALL;
return 0;
}
if ((*nparams) != BSD_CPU_STATS_ALL) {
virReportInvalidArg(*nparams,
_("nparams in %s must be equal to %d"),
__FUNCTION__, BSD_CPU_STATS_ALL);
return -1;
}
clkinfo_size = sizeof(clkinfo);
if (sysctlbyname("kern.clockrate", &clkinfo, &clkinfo_size, NULL, 0) < 0) {
virReportSystemError(errno,
_("sysctl failed for '%s'"),
"kern.clockrate");
return -1;
}
stathz = clkinfo.stathz;
hz = clkinfo.hz;
if (cpuNum == VIR_NODE_CPU_STATS_ALL_CPUS) {
sysctl_name = "kern.cp_time";
cpu_times_num = 1;
offset = 0;
} else {
sysctl_name = "kern.cp_times";
cpu_times_num = virHostCPUGetCountAppleFreeBSD();
if (cpuNum >= cpu_times_num) {
virReportInvalidArg(cpuNum,
_("Invalid cpuNum in %s"),
__FUNCTION__);
return -1;
}
offset = cpu_times_num * CPUSTATES;
}
cpu_times_size = sizeof(long) * cpu_times_num * CPUSTATES;
if (VIR_ALLOC_N(cpu_times, cpu_times_num * CPUSTATES) < 0)
goto cleanup;
if (sysctlbyname(sysctl_name, cpu_times, &cpu_times_size, NULL, 0) < 0) {
virReportSystemError(errno,
_("sysctl failed for '%s'"),
sysctl_name);
goto cleanup;
}
for (i = 0; cpu_map[i].field != NULL; i++) {
virNodeCPUStatsPtr param = &params[i];
if (virStrcpyStatic(param->field, cpu_map[i].field) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Field '%s' too long for destination"),
cpu_map[i].field);
goto cleanup;
}
param->value = 0;
for (j = 0; j < ARRAY_CARDINALITY(cpu_map[i].idx); j++)
param->value += cpu_times[offset + cpu_map[i].idx[j]] * TICK_TO_NSEC;
}
ret = 0;
cleanup:
VIR_FREE(cpu_times);
return ret;
}
#endif /* __FreeBSD__ */
/*
* Even though it doesn't exist on some platforms, the code is adjusted for
* graceful handling of that so that we don't have too many stub functions.
*/
#define SYSFS_SYSTEM_PATH "/sys/devices/system"
#ifdef __linux__
# define CPUINFO_PATH "/proc/cpuinfo"
# define PROCSTAT_PATH "/proc/stat"
# define LINUX_NB_CPU_STATS 4
int
virHostCPUGetSocket(unsigned int cpu, unsigned int *socket)
{
int tmp;
int ret = virFileReadValueInt(&tmp,
"%s/cpu/cpu%u/topology/physical_package_id",
SYSFS_SYSTEM_PATH, cpu);
/* If the file is not there, it's 0 */
if (ret == -2)
tmp = 0;
else if (ret < 0)
return -1;
/* Some architectures might have '-1' validly in the file, but that actually
* means there are no sockets, so from our point of view it's all one socket,
* i.e. socket 0. Similarly when the file does not exist. */
if (tmp < 0)
tmp = 0;
*socket = tmp;
return 0;
}
int
virHostCPUGetCore(unsigned int cpu, unsigned int *core)
{
int ret = virFileReadValueUint(core,
"%s/cpu/cpu%u/topology/core_id",
SYSFS_SYSTEM_PATH, cpu);
/* If the file is not there, it's 0 */
if (ret == -2)
*core = 0;
else if (ret < 0)
return -1;
return 0;
}
virBitmapPtr
virHostCPUGetSiblingsList(unsigned int cpu)
{
virBitmapPtr ret = NULL;
int rv = -1;
rv = virFileReadValueBitmap(&ret,
"%s/cpu/cpu%u/topology/thread_siblings_list",
SYSFS_SYSTEM_PATH, cpu);
if (rv == -2) {
/* If the file doesn't exist, the threadis its only sibling */
ret = virBitmapNew(cpu + 1);
if (ret)
ignore_value(virBitmapSetBit(ret, cpu));
}
return ret;
}
static unsigned long
virHostCPUCountThreadSiblings(unsigned int cpu)
{
virBitmapPtr siblings_map;
unsigned long ret = 0;
if (!(siblings_map = virHostCPUGetSiblingsList(cpu)))
goto cleanup;
ret = virBitmapCountBits(siblings_map);
cleanup:
virBitmapFree(siblings_map);
return ret;
}
/* parses a node entry, returning number of processors in the node and
* filling arguments */
static int
ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(3)
ATTRIBUTE_NONNULL(4) ATTRIBUTE_NONNULL(6)
ATTRIBUTE_NONNULL(7) ATTRIBUTE_NONNULL(8)
ATTRIBUTE_NONNULL(9)
virHostCPUParseNode(const char *node,
virArch arch,
virBitmapPtr present_cpus_map,
virBitmapPtr online_cpus_map,
int threads_per_subcore,
int *sockets,
int *cores,
int *threads,
int *offline)
{
int ret = -1;
int processors = 0;
DIR *cpudir = NULL;
struct dirent *cpudirent = NULL;
virBitmapPtr node_cpus_map = NULL;
virBitmapPtr sockets_map = NULL;
virBitmapPtr *cores_maps = NULL;
int npresent_cpus = virBitmapSize(present_cpus_map);
unsigned int sock_max = 0;
unsigned int sock;
unsigned int core;
size_t i;
int siblings;
unsigned int cpu;
int direrr;
*threads = 0;
*cores = 0;
*sockets = 0;
if (virDirOpen(&cpudir, node) < 0)
goto cleanup;
/* Keep track of the CPUs that belong to the current node */
if (!(node_cpus_map = virBitmapNew(npresent_cpus)))
goto cleanup;
/* enumerate sockets in the node */
if (!(sockets_map = virBitmapNewEmpty()))
goto cleanup;
while ((direrr = virDirRead(cpudir, &cpudirent, node)) > 0) {
if (sscanf(cpudirent->d_name, "cpu%u", &cpu) != 1)
continue;
if (!virBitmapIsBitSet(present_cpus_map, cpu))
continue;
/* Mark this CPU as part of the current node */
if (virBitmapSetBit(node_cpus_map, cpu) < 0)
goto cleanup;
if (!virBitmapIsBitSet(online_cpus_map, cpu))
continue;
if (virHostCPUGetSocket(cpu, &sock) < 0)
goto cleanup;
if (virBitmapSetBitExpand(sockets_map, sock) < 0)
goto cleanup;
if (sock > sock_max)
sock_max = sock;
}
if (direrr < 0)
goto cleanup;
sock_max++;
/* allocate cores maps for each socket */
if (VIR_ALLOC_N(cores_maps, sock_max) < 0)
goto cleanup;
for (i = 0; i < sock_max; i++)
if (!(cores_maps[i] = virBitmapNewEmpty()))
goto cleanup;
/* Iterate over all CPUs in the node, in ascending order */
for (cpu = 0; cpu < npresent_cpus; cpu++) {
/* Skip CPUs that are not part of the current node */
if (!virBitmapIsBitSet(node_cpus_map, cpu))
continue;
if (!virBitmapIsBitSet(online_cpus_map, cpu)) {
if (threads_per_subcore > 0 &&
cpu % threads_per_subcore != 0 &&
virBitmapIsBitSet(online_cpus_map,
cpu - (cpu % threads_per_subcore))) {
/* Secondary offline threads are counted as online when
* subcores are in use and the corresponding primary
* thread is online */
processors++;
} else {
/* But they are counted as offline otherwise */
(*offline)++;
}
continue;
}
processors++;
if (virHostCPUGetSocket(cpu, &sock) < 0)
goto cleanup;
if (!virBitmapIsBitSet(sockets_map, sock)) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("CPU socket topology has changed"));
goto cleanup;
}
/* Parse core */
if (ARCH_IS_S390(arch)) {
/* logical cpu is equivalent to a core on s390 */
core = cpu;
} else {
if (virHostCPUGetCore(cpu, &core) < 0)
goto cleanup;
}
if (virBitmapSetBitExpand(cores_maps[sock], core) < 0)
goto cleanup;
if (!(siblings = virHostCPUCountThreadSiblings(cpu)))
goto cleanup;
if (siblings > *threads)
*threads = siblings;
}
/* finalize the returned data */
*sockets = virBitmapCountBits(sockets_map);
for (i = 0; i < sock_max; i++) {
if (!virBitmapIsBitSet(sockets_map, i))
continue;
core = virBitmapCountBits(cores_maps[i]);
if (core > *cores)
*cores = core;
}
if (threads_per_subcore > 0) {
/* The thread count ignores offline threads, which means that only
* only primary threads have been considered so far. If subcores
* are in use, we need to also account for secondary threads */
*threads *= threads_per_subcore;
}
ret = processors;
cleanup:
VIR_DIR_CLOSE(cpudir);
if (cores_maps)
for (i = 0; i < sock_max; i++)
virBitmapFree(cores_maps[i]);
VIR_FREE(cores_maps);
virBitmapFree(sockets_map);
virBitmapFree(node_cpus_map);
return ret;
}
/* Check whether the host subcore configuration is valid.
*
* A valid configuration is one where no secondary thread is online;
* the primary thread in a subcore is always the first one */
static bool
virHostCPUHasValidSubcoreConfiguration(int threads_per_subcore)
{
virBitmapPtr online_cpus = NULL;
int cpu = -1;
bool ret = false;
/* No point in checking if subcores are not in use */
if (threads_per_subcore <= 0)
goto cleanup;
if (!(online_cpus = virHostCPUGetOnlineBitmap()))
goto cleanup;
while ((cpu = virBitmapNextSetBit(online_cpus, cpu)) >= 0) {
/* A single online secondary thread is enough to
* make the configuration invalid */
if (cpu % threads_per_subcore != 0)
goto cleanup;
}
ret = true;
cleanup:
virBitmapFree(online_cpus);
return ret;
}
/**
* virHostCPUParseFrequencyString:
* @str: string to be parsed
* @prefix: expected prefix
* @mhz: output location
*
* Parse a /proc/cpuinfo line and extract the CPU frequency, if present.
*
* The expected format of @str looks like
*
* cpu MHz : 2100.000
*
* where @prefix ("cpu MHz" in the example), is architecture-dependent.
*
* The decimal part of the CPU frequency, as well as all whitespace, is
* ignored.
*
* Returns: 0 when the string has been parsed successfully and the CPU
* frequency has been stored in @mhz, >0 when the string has not
* been parsed but no error has occurred, <0 on failure.
*/
static int
virHostCPUParseFrequencyString(const char *str,
const char *prefix,
unsigned int *mhz)
{
char *p;
unsigned int ui;
/* If the string doesn't start with the expected prefix, then
* we're not looking at the right string and we should move on */
if (!STRPREFIX(str, prefix))
return 1;
/* Skip the prefix */
str += strlen(prefix);
/* Skip all whitespace */
while (c_isspace(*str))
str++;
if (*str == '\0')
goto error;
/* Skip the colon. If anything but a colon is found, then we're
* not looking at the right string and we should move on */
if (*str != ':')
return 1;
str++;
/* Skip all whitespace */
while (c_isspace(*str))
str++;
if (*str == '\0')
goto error;
/* Parse the frequency. We expect an unsigned value, optionally
* followed by a fractional part (which gets discarded) or some
* leading whitespace */
if (virStrToLong_ui(str, &p, 10, &ui) < 0 ||
(*p != '.' && *p != '\0' && !c_isspace(*p))) {
goto error;
}
*mhz = ui;
return 0;
error:
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Missing or invalid CPU frequency in %s"),
CPUINFO_PATH);
return -1;
}
static int
virHostCPUParseFrequency(FILE *cpuinfo,
virArch arch,
unsigned int *mhz)
{
const char *prefix = NULL;
char line[1024];
/* No sensible way to retrieve CPU frequency */
if (ARCH_IS_ARM(arch))
return 0;
if (ARCH_IS_X86(arch))
prefix = "cpu MHz";
else if (ARCH_IS_PPC(arch))
prefix = "clock";
else if (ARCH_IS_S390(arch))
prefix = "cpu MHz dynamic";
if (!prefix) {
VIR_WARN("%s is not supported by the %s parser",
virArchToString(arch),
CPUINFO_PATH);
return 1;
}
while (fgets(line, sizeof(line), cpuinfo) != NULL) {
if (virHostCPUParseFrequencyString(line, prefix, mhz) < 0)
return -1;
}
return 0;
}
int
virHostCPUGetInfoPopulateLinux(FILE *cpuinfo,
virArch arch,
unsigned int *cpus,
unsigned int *mhz,
unsigned int *nodes,
unsigned int *sockets,
unsigned int *cores,
unsigned int *threads)
{
virBitmapPtr present_cpus_map = NULL;
virBitmapPtr online_cpus_map = NULL;
DIR *nodedir = NULL;
struct dirent *nodedirent = NULL;
int nodecpus, nodecores, nodesockets, nodethreads, offline = 0;
int threads_per_subcore = 0;
unsigned int node;
int ret = -1;
char *sysfs_nodedir = NULL;
char *sysfs_cpudir = NULL;
int direrr;
*mhz = 0;
*cpus = *nodes = *sockets = *cores = *threads = 0;
/* Start with parsing CPU clock speed from /proc/cpuinfo */
if (virHostCPUParseFrequency(cpuinfo, arch, mhz) < 0) {
VIR_WARN("Unable to parse CPU frequency information from %s",
CPUINFO_PATH);
}
/* Get information about what CPUs are present in the host and what
* CPUs are online, so that we don't have to so for each node */
present_cpus_map = virHostCPUGetPresentBitmap();
if (!present_cpus_map)
goto cleanup;
online_cpus_map = virHostCPUGetOnlineBitmap();
if (!online_cpus_map)
goto cleanup;
/* OK, we've parsed clock speed out of /proc/cpuinfo. Get the
* core, node, socket, thread and topology information from /sys
*/
if (virAsprintf(&sysfs_nodedir, "%s/node", SYSFS_SYSTEM_PATH) < 0)
goto cleanup;
if (virDirOpenQuiet(&nodedir, sysfs_nodedir) < 0) {
/* the host isn't probably running a NUMA architecture */
goto fallback;
}
/* PPC-KVM needs the secondary threads of a core to be offline on the
* host. The kvm scheduler brings the secondary threads online in the
* guest context. Moreover, P8 processor has split-core capability
* where, there can be 1,2 or 4 subcores per core. The primaries of the
* subcores alone will be online on the host for a subcore in the
* host. Even though the actual threads per core for P8 processor is 8,
* depending on the subcores_per_core = 1, 2 or 4, the threads per
* subcore will vary accordingly to 8, 4 and 2 respectively.
* So, On host threads_per_core what is arrived at from sysfs in the
* current logic is actually the subcores_per_core. Threads per subcore
* can only be obtained from the kvm device. For example, on P8 wih 1
* core having 8 threads, sub_cores_percore=4, the threads 0,2,4 & 6
* will be online. The sysfs reflects this and in the current logic
* variable 'threads' will be 4 which is nothing but subcores_per_core.
* If the user tampers the cpu online/offline states using chcpu or other
* means, then it is an unsupported configuration for kvm.
* The code below tries to keep in mind
* - when the libvirtd is run inside a KVM guest or Phyp based guest.
* - Or on the kvm host where user manually tampers the cpu states to
* offline/online randomly.
* On hosts other than POWER this will be 0, in which case a simpler
* thread-counting logic will be used */
if ((threads_per_subcore = virHostCPUGetThreadsPerSubcore(arch)) < 0)
goto cleanup;
/* If the subcore configuration is not valid, just pretend subcores
* are not in use and count threads one by one */
if (!virHostCPUHasValidSubcoreConfiguration(threads_per_subcore))
threads_per_subcore = 0;
while ((direrr = virDirRead(nodedir, &nodedirent, sysfs_nodedir)) > 0) {
if (sscanf(nodedirent->d_name, "node%u", &node) != 1)
continue;
(*nodes)++;
if (virAsprintf(&sysfs_cpudir, "%s/node/%s", SYSFS_SYSTEM_PATH,
nodedirent->d_name) < 0)
goto cleanup;
if ((nodecpus = virHostCPUParseNode(sysfs_cpudir, arch,
present_cpus_map,
online_cpus_map,
threads_per_subcore,
&nodesockets, &nodecores,
&nodethreads, &offline)) < 0)
goto cleanup;
VIR_FREE(sysfs_cpudir);
*cpus += nodecpus;
if (nodesockets > *sockets)
*sockets = nodesockets;
if (nodecores > *cores)
*cores = nodecores;
if (nodethreads > *threads)
*threads = nodethreads;
}
if (direrr < 0)
goto cleanup;
if (*cpus && *nodes)
goto done;
fallback:
VIR_FREE(sysfs_cpudir);
if (virAsprintf(&sysfs_cpudir, "%s/cpu", SYSFS_SYSTEM_PATH) < 0)
goto cleanup;
if ((nodecpus = virHostCPUParseNode(sysfs_cpudir, arch,
present_cpus_map,
online_cpus_map,
threads_per_subcore,
&nodesockets, &nodecores,
&nodethreads, &offline)) < 0)
goto cleanup;
*nodes = 1;
*cpus = nodecpus;
*sockets = nodesockets;
*cores = nodecores;
*threads = nodethreads;
done:
/* There should always be at least one cpu, socket, node, and thread. */
if (*cpus == 0) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("no CPUs found"));
goto cleanup;
}
if (*sockets == 0) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("no sockets found"));
goto cleanup;
}
if (*threads == 0) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("no threads found"));
goto cleanup;
}
/* Now check if the topology makes sense. There are machines that don't
* expose their real number of nodes or for example the AMD Bulldozer
* architecture that exposes their Clustered integer core modules as both
* threads and cores. This approach throws off our detection. Unfortunately
* the nodeinfo structure isn't designed to carry the full topology so
* we're going to lie about the detected topology to notify the user
* to check the host capabilities for the actual topology. */
if ((*nodes *
*sockets *
*cores *
*threads) != (*cpus + offline)) {
*nodes = 1;
*sockets = 1;
*cores = *cpus + offline;
*threads = 1;
}
ret = 0;
cleanup:
VIR_DIR_CLOSE(nodedir);
virBitmapFree(present_cpus_map);
virBitmapFree(online_cpus_map);
VIR_FREE(sysfs_nodedir);
VIR_FREE(sysfs_cpudir);
return ret;
}
# define TICK_TO_NSEC (1000ull * 1000ull * 1000ull / sysconf(_SC_CLK_TCK))
int
virHostCPUGetStatsLinux(FILE *procstat,
int cpuNum,
virNodeCPUStatsPtr params,
int *nparams)
{
int ret = -1;
char line[1024];
unsigned long long usr, ni, sys, idle, iowait;
unsigned long long irq, softirq, steal, guest, guest_nice;
char cpu_header[4 + INT_BUFSIZE_BOUND(cpuNum)];
if ((*nparams) == 0) {
/* Current number of cpu stats supported by linux */
*nparams = LINUX_NB_CPU_STATS;
ret = 0;
goto cleanup;
}
if ((*nparams) != LINUX_NB_CPU_STATS) {
virReportInvalidArg(*nparams,
_("nparams in %s must be equal to %d"),
__FUNCTION__, LINUX_NB_CPU_STATS);
goto cleanup;
}
if (cpuNum == VIR_NODE_CPU_STATS_ALL_CPUS) {
strcpy(cpu_header, "cpu ");
} else {
snprintf(cpu_header, sizeof(cpu_header), "cpu%d ", cpuNum);
}
while (fgets(line, sizeof(line), procstat) != NULL) {
char *buf = line;
if (STRPREFIX(buf, cpu_header)) { /* aka logical CPU time */
if (sscanf(buf,
"%*s %llu %llu %llu %llu %llu" /* user ~ iowait */
"%llu %llu %llu %llu %llu", /* irq ~ guest_nice */
&usr, &ni, &sys, &idle, &iowait,
&irq, &softirq, &steal, &guest, &guest_nice) < 4) {
continue;
}
if (virHostCPUStatsAssign(&params[0], VIR_NODE_CPU_STATS_KERNEL,
(sys + irq + softirq) * TICK_TO_NSEC) < 0)
goto cleanup;
if (virHostCPUStatsAssign(&params[1], VIR_NODE_CPU_STATS_USER,
(usr + ni) * TICK_TO_NSEC) < 0)
goto cleanup;
if (virHostCPUStatsAssign(&params[2], VIR_NODE_CPU_STATS_IDLE,
idle * TICK_TO_NSEC) < 0)
goto cleanup;
if (virHostCPUStatsAssign(&params[3], VIR_NODE_CPU_STATS_IOWAIT,
iowait * TICK_TO_NSEC) < 0)
goto cleanup;
ret = 0;
goto cleanup;
}
}
virReportInvalidArg(cpuNum,
_("Invalid cpuNum in %s"),
__FUNCTION__);
cleanup:
return ret;
}
/* Determine the number of CPUs (maximum CPU id + 1) from a file containing
* a list of CPU ids, like the Linux sysfs cpu/present file */
static int
virHostCPUParseCountLinux(void)
{
char *str = NULL;
char *tmp;
int ret = -1;
if (virFileReadValueString(&str, "%s/cpu/present", SYSFS_SYSTEM_PATH) < 0)
return -1;
tmp = str;
do {
if (virStrToLong_i(tmp, &tmp, 10, &ret) < 0 ||
!strchr(",-", *tmp)) {
virReportError(VIR_ERR_NO_SUPPORT,
_("failed to parse %s"), str);
ret = -1;
goto cleanup;
}
} while (*tmp++ && *tmp);
ret++;
cleanup:
VIR_FREE(str);
return ret;
}
#endif
int
virHostCPUGetOnline(unsigned int cpu, bool *online)
{
unsigned int tmp = 0;
int ret = virFileReadValueUint(&tmp,
"%s/cpu/cpu%u/online",
SYSFS_SYSTEM_PATH, cpu);
/* If the file is not there, it's online (doesn't support offlining) */
if (ret == -2)
tmp = 1;
else if (ret < 0)
return -1;
*online = tmp;
return 0;
}
int
virHostCPUStatsAssign(virNodeCPUStatsPtr param,
const char *name,
unsigned long long value)
{
if (virStrcpyStatic(param->field, name) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR,
"%s", _("kernel cpu time field is too long"
" for the destination"));
return -1;
}
param->value = value;
return 0;
}
int
virHostCPUGetInfo(virArch hostarch ATTRIBUTE_UNUSED,
unsigned int *cpus ATTRIBUTE_UNUSED,
unsigned int *mhz ATTRIBUTE_UNUSED,
unsigned int *nodes ATTRIBUTE_UNUSED,
unsigned int *sockets ATTRIBUTE_UNUSED,
unsigned int *cores ATTRIBUTE_UNUSED,
unsigned int *threads ATTRIBUTE_UNUSED)
{
#ifdef __linux__
int ret = -1;
FILE *cpuinfo = fopen(CPUINFO_PATH, "r");
if (!cpuinfo) {
virReportSystemError(errno,
_("cannot open %s"), CPUINFO_PATH);
return -1;
}
ret = virHostCPUGetInfoPopulateLinux(cpuinfo, hostarch,
cpus, mhz, nodes,
sockets, cores, threads);
if (ret < 0)
goto cleanup;
cleanup:
VIR_FORCE_FCLOSE(cpuinfo);
return ret;
#elif defined(__FreeBSD__) || defined(__APPLE__)
unsigned long cpu_freq;
size_t cpu_freq_len = sizeof(cpu_freq);
*cpus = virHostCPUGetCountAppleFreeBSD();
if (*cpus == -1)
return -1;
*nodes = 1;
*sockets = 1;
*cores = *cpus;
*threads = 1;
# ifdef __FreeBSD__
/* dev.cpu.%d.freq reports current active CPU frequency. It is provided by
* the cpufreq(4) framework. However, it might be disabled or no driver
* available. In this case fallback to "hw.clockrate" which reports boot time
* CPU frequency. */
if (sysctlbyname("dev.cpu.0.freq", &cpu_freq, &cpu_freq_len, NULL, 0) < 0) {
if (sysctlbyname("hw.clockrate", &cpu_freq, &cpu_freq_len, NULL, 0) < 0) {
virReportSystemError(errno, "%s", _("cannot obtain CPU freq"));
return -1;
}
}
*mhz = cpu_freq;
# else
if (sysctlbyname("hw.cpufrequency", &cpu_freq, &cpu_freq_len, NULL, 0) < 0) {
virReportSystemError(errno, "%s", _("cannot obtain CPU freq"));
return -1;
}
*mhz = cpu_freq / 1000000;
# endif
return 0;
#else
/* XXX Solaris will need an impl later if they port QEMU driver */
virReportError(VIR_ERR_NO_SUPPORT, "%s",
_("node info not implemented on this platform"));
return -1;
#endif
}
int
virHostCPUGetStats(int cpuNum ATTRIBUTE_UNUSED,
virNodeCPUStatsPtr params ATTRIBUTE_UNUSED,
int *nparams ATTRIBUTE_UNUSED,
unsigned int flags)
{
virCheckFlags(0, -1);
#ifdef __linux__
{
int ret;
FILE *procstat = fopen(PROCSTAT_PATH, "r");
if (!procstat) {
virReportSystemError(errno,
_("cannot open %s"), PROCSTAT_PATH);
return -1;
}
ret = virHostCPUGetStatsLinux(procstat, cpuNum, params, nparams);
VIR_FORCE_FCLOSE(procstat);
return ret;
}
#elif defined(__FreeBSD__)
return virHostCPUGetStatsFreeBSD(cpuNum, params, nparams);
#else
virReportError(VIR_ERR_NO_SUPPORT, "%s",
_("node CPU stats not implemented on this platform"));
return -1;
#endif
}
int
virHostCPUGetCount(void)
{
#if defined(__linux__)
return virHostCPUParseCountLinux();
#elif defined(__FreeBSD__) || defined(__APPLE__)
return virHostCPUGetCountAppleFreeBSD();
#else
virReportError(VIR_ERR_NO_SUPPORT, "%s",
_("host cpu counting not implemented on this platform"));
return -1;
#endif
}
bool
virHostCPUHasBitmap(void)
{
#ifdef __linux__
return true;
#else
return false;
#endif
}
virBitmapPtr
virHostCPUGetPresentBitmap(void)
{
#ifdef __linux__
virBitmapPtr ret = NULL;
virFileReadValueBitmap(&ret, "%s/cpu/present", SYSFS_SYSTEM_PATH);
return ret;
#else
virReportError(VIR_ERR_NO_SUPPORT, "%s",
_("node present CPU map not implemented on this platform"));
return NULL;
#endif
}
virBitmapPtr
virHostCPUGetOnlineBitmap(void)
{
#ifdef __linux__
virBitmapPtr ret = NULL;
virFileReadValueBitmap(&ret, "%s/cpu/online", SYSFS_SYSTEM_PATH);
return ret;
#else
virReportError(VIR_ERR_NO_SUPPORT, "%s",
_("node online CPU map not implemented on this platform"));
return NULL;
#endif
}
int
virHostCPUGetMap(unsigned char **cpumap,
unsigned int *online,
unsigned int flags)
{
virBitmapPtr cpus = NULL;
int ret = -1;
int dummy;
virCheckFlags(0, -1);
if (!cpumap && !online)
return virHostCPUGetCount();
if (!(cpus = virHostCPUGetOnlineBitmap()))
goto cleanup;
if (cpumap && virBitmapToData(cpus, cpumap, &dummy) < 0)
goto cleanup;
if (online)
*online = virBitmapCountBits(cpus);
ret = virHostCPUGetCount();
cleanup:
if (ret < 0 && cpumap)
VIR_FREE(*cpumap);
virBitmapFree(cpus);
return ret;
}
#if HAVE_LINUX_KVM_H && defined(KVM_CAP_PPC_SMT)
/* Get the number of threads per subcore.
*
* This will be 2, 4 or 8 on POWER hosts, depending on the current
* micro-threading configuration, and 0 everywhere else.
*
* Returns the number of threads per subcore if subcores are in use, zero
* if subcores are not in use, and a negative value on error */
int
virHostCPUGetThreadsPerSubcore(virArch arch)
{
int threads_per_subcore = 0;
int kvmfd;
if (ARCH_IS_PPC64(arch)) {
/* It's okay if /dev/kvm doesn't exist, because
* a. we might be running in a guest
* b. the kvm module might not be installed or enabled
* In either case, falling back to the subcore-unaware thread
* counting logic is the right thing to do */
if (!virFileExists(KVM_DEVICE))
goto out;
if ((kvmfd = open(KVM_DEVICE, O_RDONLY)) < 0) {
/* This can happen when running as a regular user if
* permissions are tight enough, in which case erroring out
* is better than silently falling back and reporting
* different nodeinfo depending on the user */
virReportSystemError(errno,
_("Failed to open '%s'"),
KVM_DEVICE);
threads_per_subcore = -1;
goto out;
}
/* For Phyp and KVM based guests the ioctl for KVM_CAP_PPC_SMT
* returns zero and both primary and secondary threads will be
* online */
threads_per_subcore = ioctl(kvmfd,
KVM_CHECK_EXTENSION,
KVM_CAP_PPC_SMT);
VIR_FORCE_CLOSE(kvmfd);
}
out:
return threads_per_subcore;
}
#else
/* Fallback for nodeGetThreadsPerSubcore() used when KVM headers
* are not available on the system */
int
virHostCPUGetThreadsPerSubcore(virArch arch ATTRIBUTE_UNUSED)
{
return 0;
}
#endif /* HAVE_LINUX_KVM_H && defined(KVM_CAP_PPC_SMT) */
#if HAVE_LINUX_KVM_H
int
virHostCPUGetKVMMaxVCPUs(void)
{
int fd;
int ret;
if ((fd = open(KVM_DEVICE, O_RDONLY)) < 0) {
virReportSystemError(errno, _("Unable to open %s"), KVM_DEVICE);
return -1;
}
# ifdef KVM_CAP_MAX_VCPUS
/* at first try KVM_CAP_MAX_VCPUS to determine the maximum count */
if ((ret = ioctl(fd, KVM_CHECK_EXTENSION, KVM_CAP_MAX_VCPUS)) > 0)
goto cleanup;
# endif /* KVM_CAP_MAX_VCPUS */
/* as a fallback get KVM_CAP_NR_VCPUS (the recommended maximum number of
* vcpus). Note that on most machines this is set to 160. */
if ((ret = ioctl(fd, KVM_CHECK_EXTENSION, KVM_CAP_NR_VCPUS)) > 0)
goto cleanup;
/* if KVM_CAP_NR_VCPUS doesn't exist either, kernel documentation states
* that 4 should be used as the maximum number of cpus */
ret = 4;
cleanup:
VIR_FORCE_CLOSE(fd);
return ret;
}
#else
int
virHostCPUGetKVMMaxVCPUs(void)
{
virReportSystemError(ENOSYS, "%s",
_("KVM is not supported on this platform"));
return -1;
}
#endif /* HAVE_LINUX_KVM_H */
#ifdef __linux__
/*
* Returns 0 if the microcode version is unknown or cannot be read for
* some reason.
*/
unsigned int
virHostCPUGetMicrocodeVersion(void)
{
char *outbuf = NULL;
char *cur;
unsigned int version = 0;
if (virFileReadHeaderQuiet(CPUINFO_PATH, 4096, &outbuf) < 0) {
char ebuf[1024];
VIR_DEBUG("Failed to read microcode version from %s: %s",
CPUINFO_PATH, virStrerror(errno, ebuf, sizeof(ebuf)));
return 0;
}
/* Account for format 'microcode : XXXX'*/
if (!(cur = strstr(outbuf, "microcode")) ||
!(cur = strchr(cur, ':')))
goto cleanup;
cur++;
/* Linux places the microcode revision in a 32-bit integer, so
* ui is fine for us too. */
if (virStrToLong_ui(cur, &cur, 0, &version) < 0)
goto cleanup;
cleanup:
VIR_FREE(outbuf);
return version;
}
#else
unsigned int
virHostCPUGetMicrocodeVersion(void)
{
return 0;
}
#endif /* __linux__ */
#if HAVE_LINUX_KVM_H && defined(KVM_GET_MSRS) && \
(defined(__i386__) || defined(__x86_64__)) && \
(defined(__linux__) || defined(__FreeBSD__))
static int
virHostCPUGetMSRFromKVM(unsigned long index,
uint64_t *result)
{
VIR_AUTOCLOSE fd = -1;
struct {
struct kvm_msrs header;
struct kvm_msr_entry entry;
} msr = {
.header = { .nmsrs = 1 },
.entry = { .index = index },
};
if ((fd = open(KVM_DEVICE, O_RDONLY)) < 0) {
virReportSystemError(errno, _("Unable to open %s"), KVM_DEVICE);
return -1;
}
if (ioctl(fd, KVM_GET_MSRS, &msr) < 0) {
VIR_DEBUG("Cannot get MSR 0x%lx from KVM", index);
return 1;
}
*result = msr.entry.data;
return 0;
}
/*
* Returns 0 on success,
* 1 when the MSR is not supported by the host CPU,
* -1 on error.
*/
int
virHostCPUGetMSR(unsigned long index,
uint64_t *msr)
{
VIR_AUTOCLOSE fd = -1;
char ebuf[1024];
*msr = 0;
if ((fd = open(MSR_DEVICE, O_RDONLY)) < 0) {
VIR_DEBUG("Unable to open %s: %s",
MSR_DEVICE, virStrerror(errno, ebuf, sizeof(ebuf)));
} else {
int rc = pread(fd, msr, sizeof(*msr), index);
if (rc == sizeof(*msr))
return 0;
if (rc < 0 && errno == EIO) {
VIR_DEBUG("CPU does not support MSR 0x%lx", index);
return 1;
}
VIR_DEBUG("Cannot read MSR 0x%lx from %s: %s",
index, MSR_DEVICE, virStrerror(errno, ebuf, sizeof(ebuf)));
}
VIR_DEBUG("Falling back to KVM ioctl");
return virHostCPUGetMSRFromKVM(index, msr);
}
# define VMX_PROCBASED_CTLS2_MSR 0x48b
# define VMX_USE_TSC_SCALING (1 << 25)
/*
* This function should only be called when the host CPU supports invariant TSC
* (invtsc CPUID feature).
*
* Returns pointer to the TSC info structure on success,
* NULL when TSC cannot be probed otherwise.
*/
virHostCPUTscInfoPtr
virHostCPUGetTscInfo(void)
{
virHostCPUTscInfoPtr info;
VIR_AUTOCLOSE kvmFd = -1;
VIR_AUTOCLOSE vmFd = -1;
VIR_AUTOCLOSE vcpuFd = -1;
uint64_t msr = 0;
int rc;
if ((kvmFd = open(KVM_DEVICE, O_RDONLY)) < 0) {
virReportSystemError(errno, _("Unable to open %s"), KVM_DEVICE);
return NULL;
}
if ((vmFd = ioctl(kvmFd, KVM_CREATE_VM, 0)) < 0) {
virReportSystemError(errno, "%s",
_("Unable to create KVM VM for TSC probing"));
return NULL;
}
if ((vcpuFd = ioctl(vmFd, KVM_CREATE_VCPU, 0)) < 0) {
virReportSystemError(errno, "%s",
_("Unable to create KVM vCPU for TSC probing"));
return NULL;
}
if ((rc = ioctl(vcpuFd, KVM_GET_TSC_KHZ)) < 0) {
virReportSystemError(errno, "%s",
_("Unable to probe TSC frequency"));
return NULL;
}
if (VIR_ALLOC(info) < 0)
return NULL;
info->frequency = rc * 1000ULL;
if (virHostCPUGetMSR(VMX_PROCBASED_CTLS2_MSR, &msr) == 0) {
/* High 32 bits of the MSR value indicate whether specific control
* can be set to 1. */
msr >>= 32;
info->scaling = virTristateBoolFromBool(!!(msr & VMX_USE_TSC_SCALING));
}
VIR_DEBUG("Detected TSC frequency %llu Hz, scaling %s",
info->frequency, virTristateBoolTypeToString(info->scaling));
return info;
}
#else
int
virHostCPUGetMSR(unsigned long index ATTRIBUTE_UNUSED,
uint64_t *msr ATTRIBUTE_UNUSED)
{
virReportSystemError(ENOSYS, "%s",
_("Reading MSRs is not supported on this platform"));
return -1;
}
virHostCPUTscInfoPtr
virHostCPUGetTscInfo(void)
{
virReportSystemError(ENOSYS, "%s",
_("Probing TSC is not supported on this platform"));
return NULL;
}
#endif /* HAVE_LINUX_KVM_H && defined(KVM_GET_MSRS) && \
(defined(__i386__) || defined(__x86_64__)) && \
(defined(__linux__) || defined(__FreeBSD__)) */
Reference in New Issue View Git Blame Copy Permalink