Add helper function virHostCPUGetHaltPollTime to obtain halt polling time. If the kernel support halt polling time statistic, and mount debugfs. This function will take effect on KVM VMs. Signed-off-by: Yang Fei <yangfei85(a)huawei.com&gt; --- src/libvirt_private.syms | 1 + src/util/virhostcpu.c | 39 +++++++++++++++++++++++++++++++++++++++ src/util/virhostcpu.h | 4 ++++ 3 files changed, 44 insertions(+) diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms index 5429a82a7c..531ba03cf7 100644 --- a/src/libvirt_private.syms +++ b/src/libvirt_private.syms @@ -2374,6 +2374,7 @@ virHookPresent; # util/virhostcpu.h virHostCPUGetAvailableCPUsBitmap; virHostCPUGetCount; +virHostCPUGetHaltPollTime; virHostCPUGetInfo; virHostCPUGetKVMMaxVCPUs; virHostCPUGetMap; diff --git a/src/util/virhostcpu.c b/src/util/virhostcpu.c index bf7fda23af..7f577c3e3e 100644 --- a/src/util/virhostcpu.c +++ b/src/util/virhostcpu.c @@ -1535,3 +1535,42 @@ virHostCPUGetSignature(char **signature) } #endif /* __linux__ */ + +int +virHostCPUGetHaltPollTime(pid_t pid, + unsigned long long *haltPollSuccess, + unsigned long long *haltPollFail) +{ + g_autofree char *pidToStr = NULL; + g_autofree char *debugFsPath = NULL; + g_autofree char *kvmPath = NULL; + struct dirent *ent = NULL; + g_autoptr(DIR) dir = NULL; + bool found = false; + + if (!(debugFsPath = virFileFindMountPoint("debugfs"))) + return -1; + + kvmPath = g_strdup_printf("%s/%s", debugFsPath, "kvm"); + if (virDirOpenQuiet(&dir, kvmPath) != 1) + return -1; + + pidToStr = g_strdup_printf("%lld%c", (long long)pid, '-'); + while (virDirRead(dir, &ent, NULL) > 0) { + if (STRPREFIX(ent->d_name, pidToStr)) { + found = true; + break; + } + } + + if (!found) + return -1; + + if (virFileReadValueUllongQuiet(haltPollSuccess, "%s/%s/%s", kvmPath, + ent->d_name, "halt_poll_success_ns") < 0 || + virFileReadValueUllongQuiet(haltPollFail, "%s/%s/%s", kvmPath, + ent->d_name, "halt_poll_fail_ns") < 0) + return -1; + + return 0; +} diff --git a/src/util/virhostcpu.h b/src/util/virhostcpu.h index fc717250d9..d98385d53f 100644 --- a/src/util/virhostcpu.h +++ b/src/util/virhostcpu.h @@ -83,3 +83,7 @@ int virHostCPUGetMSR(unsigned long index, virHostCPUTscInfo *virHostCPUGetTscInfo(void); int virHostCPUGetSignature(char **signature); + +int virHostCPUGetHaltPollTime(pid_t pid, + unsigned long long *haltPollSuccess, + unsigned long long *haltPollFail); -- 2.23.0

On 2021/7/27 16:31, Michal Prívozník wrote: Thanks for your review Michal. And do I need to send another version to fix it now? Thanks, Fei.

This function add halt polling time interface in domstats. So that we can use command 'virsh domstats VM' to get the data if system support. Signed-off-by: Yang Fei <yangfei85(a)huawei.com&gt; --- docs/manpages/virsh.rst | 4 ++++ src/libvirt-domain.c | 7 +++++++ src/qemu/qemu_driver.c | 20 ++++++++++++++++++++ 3 files changed, 31 insertions(+) diff --git a/docs/manpages/virsh.rst b/docs/manpages/virsh.rst index 87668f2b9a..20936994ce 100644 --- a/docs/manpages/virsh.rst +++ b/docs/manpages/virsh.rst @@ -2260,6 +2260,10 @@ When selecting the *--state* group the following fields are returned: * ``cpu.time`` - total cpu time spent for this domain in nanoseconds * ``cpu.user`` - user cpu time spent in nanoseconds * ``cpu.system`` - system cpu time spent in nanoseconds +* ``cpu.haltpoll.success.time`` - cpu halt polling success time spent in + nanoseconds +* ``cpu.haltpoll.fail.time`` - cpu halt polling fail time spent in + nanoseconds * ``cpu.cache.monitor.count`` - the number of cache monitors for this domain * ``cpu.cache.monitor.<num>.name`` - the name of cache monitor <num> diff --git a/src/libvirt-domain.c b/src/libvirt-domain.c index 35c0df0ebc..4eb14d4176 100644 --- a/src/libvirt-domain.c +++ b/src/libvirt-domain.c @@ -11625,6 +11625,13 @@ virConnectGetDomainCapabilities(virConnectPtr conn, * "cpu.user" - user cpu time spent in nanoseconds as unsigned long long. * "cpu.system" - system cpu time spent in nanoseconds as unsigned long * long. + * "cpu.haltpoll.success.time" - halt-polling cpu usage about the VCPU polled + * until a virtual interrupt was delivered in + * nanoseconds as unsigned long long. + * "cpu.haltpoll.fail.time" - halt-polling cpu usage about the VCPU had to schedule + * out (either because the maximum poll time was reached + * or it needed to yield the CPU) in nanoseconds as + * unsigned long long. * "cpu.cache.monitor.count" - the number of cache monitors for this domain * "cpu.cache.monitor.<num>.name" - the name of cache monitor <num> * "cpu.cache.monitor.<num>.vcpus" - vcpu list of cache monitor <num> diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index 521063d438..79308b7157 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -17857,6 +17857,23 @@ qemuDomainGetStatsCpuCgroup(virDomainObj *dom, return 0; } +static int +qemuDomainGetStatsCpuHaltPollTime(virDomainObj *dom, + virTypedParamList *params) +{ + unsigned long long haltPollSuccess = 0; + unsigned long long haltPollFail = 0; + pid_t pid = dom->pid; + + if (virHostCPUGetHaltPollTime(pid, &haltPollSuccess, &haltPollFail) < 0) + return 0; + + if (virTypedParamListAddULLong(params, haltPollSuccess, "cpu.haltpoll.success.time") < 0 || + virTypedParamListAddULLong(params, haltPollFail, "cpu.haltpoll.fail.time") < 0) + return -1; + + return 0; +} static int qemuDomainGetStatsCpu(virQEMUDriver *driver, @@ -17870,6 +17887,9 @@ qemuDomainGetStatsCpu(virQEMUDriver *driver, if (qemuDomainGetStatsCpuCache(driver, dom, params) < 0) return -1; + if (qemuDomainGetStatsCpuHaltPollTime(dom, params) < 0) + return -1; + return 0; } -- 2.23.0