Hi
On Mon, Jul 4, 2022 at 6:42 AM zhenwei pi <pizhenwei@bytedance.com
<mailto:pizhenwei@bytedance.com>> wrote:
A vCPU thread always reaches 100% utilization when:
- guest uses idle=poll
- disable HLT vm-exit
- enable MWAIT
Add new guest agent command 'guest-get-cpustats' to get guest CPU
statistics, we can know the guest workload and how busy the CPU is.
Signed-off-by: zhenwei pi <pizhenwei@bytedance.com
<mailto:pizhenwei@bytedance.com>>
---
qga/commands-posix.c | 89 ++++++++++++++++++++++++++++++++++++++++++++
qga/commands-win32.c | 6 +++
qga/qapi-schema.json | 81 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 176 insertions(+)
diff --git a/qga/commands-posix.c b/qga/commands-posix.c
index 0469dc409d..e51f4c8f03 100644
--- a/qga/commands-posix.c
+++ b/qga/commands-posix.c
@@ -2893,6 +2893,90 @@ GuestDiskStatsInfoList
*qmp_guest_get_diskstats(Error **errp)
return guest_get_diskstats(errp);
}
+GuestCpuStatsList *qmp_guest_get_cpustats(Error **errp)
+{
+ GuestCpuStatsList *head = NULL, **tail = &head;
+ const char *cpustats = "/proc/stat";
+ int clk_tck = sysconf(_SC_CLK_TCK);
+ FILE *fp;
+ size_t n;
+ char *line = NULL;
+
+ fp = fopen(cpustats, "r");
+ if (fp == NULL) {
+ error_setg_errno(errp, errno, "open(\"%s\")", cpustats);
+ return NULL;
+ }
+
+ while (getline(&line, &n, fp) != -1) {
+ GuestCpuStats *cpustat = NULL;
+ GuestLinuxCpuStats *linuxcpustat;
+ int i;
+ unsigned long user, system, idle, iowait, irq, softirq,
steal, guest;
+ unsigned long nice, guest_nice;
+ char name[64];
+
+ i = sscanf(line, "%s %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu",
+ name, &user, &nice, &system, &idle, &iowait,
&irq, &softirq,
+ &steal, &guest, &guest_nice);
+
+ /* drop "cpu 1 2 3 ...", get "cpuX 1 2 3 ..." only */
+ if ((i == EOF) || strncmp(name, "cpu", 3) || (name[3] ==
'\0')) {
+ continue;
+ }
+
+ if (i < 5) {
+ slog("Parsing cpu stat from %s failed, see \"man
proc\"", cpustats);
+ break;
+ }
+
+ cpustat = g_new0(GuestCpuStats, 1);
+ cpustat->type = GUEST_OS_TYPE_LINUXOS;
+
+ linuxcpustat = &cpustat->u.linuxos;
+ linuxcpustat->cpu = atoi(&name[3]);
+ linuxcpustat->user = user * 1000 / clk_tck;
+ linuxcpustat->nice = nice * 1000 / clk_tck;
+ linuxcpustat->system = system * 1000 / clk_tck;
+ linuxcpustat->idle = idle * 1000 / clk_tck;
+
+ if (i > 5) {
+ linuxcpustat->has_iowait = true;
+ linuxcpustat->iowait = iowait * 1000 / clk_tck;
+ }
+
+ if (i > 6) {
+ linuxcpustat->has_irq = true;
+ linuxcpustat->irq = irq * 1000 / clk_tck;
+ linuxcpustat->has_softirq = true;
+ linuxcpustat->softirq = softirq * 1000 / clk_tck;
+ }
+
+ if (i > 8) {
+ linuxcpustat->has_steal = true;
+ linuxcpustat->steal = steal * 1000 / clk_tck;
+ }
+
+ if (i > 9) {
+ linuxcpustat->has_guest = true;
+ linuxcpustat->guest = guest * 1000 / clk_tck;
+ }
+
+ if (i > 10) {
+ linuxcpustat->has_guest = true;
+ linuxcpustat->guest = guest * 1000 / clk_tck;
+ linuxcpustat->has_guestnice = true;
+ linuxcpustat->guestnice = guest_nice * 1000 / clk_tck;
+ }
+
+ QAPI_LIST_APPEND(tail, cpustat);
+ }
+
+ free(line);
+ fclose(fp);
+ return head;
+}
+
#else /* defined(__linux__) */
void qmp_guest_suspend_disk(Error **errp)
@@ -3247,6 +3331,11 @@ GuestDiskStatsInfoList
*qmp_guest_get_diskstats(Error **errp)
return NULL;
}
+GuestCpuStatsList *qmp_guest_get_cpustats(Error **errp)
+{
+ error_setg(errp, QERR_UNSUPPORTED);
+ return NULL;
+}
#endif /* CONFIG_FSFREEZE */
diff --git a/qga/commands-win32.c b/qga/commands-win32.c
index 36f94c0f9c..7ed7664715 100644
--- a/qga/commands-win32.c
+++ b/qga/commands-win32.c
@@ -2543,3 +2543,9 @@ GuestDiskStatsInfoList
*qmp_guest_get_diskstats(Error **errp)
error_setg(errp, QERR_UNSUPPORTED);
return NULL;
}
+
+GuestCpuStatsList *qmp_guest_get_cpustats(Error **errp)
+{
+ error_setg(errp, QERR_UNSUPPORTED);
+ return NULL;
+}
diff --git a/qga/qapi-schema.json b/qga/qapi-schema.json
index 9fa20e791b..3b795222e9 100644
--- a/qga/qapi-schema.json
+++ b/qga/qapi-schema.json
@@ -1576,3 +1576,84 @@
{ 'command': 'guest-get-diskstats',
'returns': ['GuestDiskStatsInfo']
}
+
+##
+# @GuestOsType:
+#
+# An enumeration of OS type
+#
+# Since: 7.1
+##
+{ 'enum': 'GuestOsType',
+ 'data': [ 'linuxos', 'windowsos' ] }
I would rather keep this enum specific to GuestCpuStats,
"GuestLinuxCpuStatsType"?
+
+
+##
+# @GuestLinuxCpuStats:
+#
+# CPU statistics of Linux
+#
+# @cpu: CPU index in guest OS
+#
+# @user: Time spent in user mode
+#
+# @nice: Time spent in user mode with low priority (nice)
+#
+# @system: Time spent in system mode
+#
+# @idle: Time spent in the idle task
+#
+# @iowait: Time waiting for I/O to complete (since Linux 2.5.41)
+#
+# @irq: Time servicing interrupts (since Linux 2.6.0-test4)
+#
+# @softirq: Time servicing softirqs (since Linux 2.6.0-test4)
+#
+# @steal: Stolen time by host (since Linux 2.6.11)
+#
+# @guest: ime spent running a virtual CPU for guest operating
systems under
+# the control of the Linux kernel (since Linux 2.6.24)
+#
+# @guestnice: Time spent running a niced guest (since Linux 2.6.33)
+#
+# Since: 7.1
+##
+{ 'struct': 'GuestLinuxCpuStats',
+ 'data': {'cpu': 'int',
+ 'user': 'uint64',
+ 'nice': 'uint64',
+ 'system': 'uint64',
+ 'idle': 'uint64',
+ '*iowait': 'uint64',
+ '*irq': 'uint64',
+ '*softirq': 'uint64',
+ '*steal': 'uint64',
+ '*guest': 'uint64',
+ '*guestnice': 'uint64'
+ } }
+
+##
+# @GuestCpuStats:
+#
+# Get statistics of each CPU in millisecond.
+#
+# - @linux: Linux style CPU statistics
+#
+# Since: 7.1
+##
+{ 'union': 'GuestCpuStats',
+ 'base': { 'type': 'GuestOsType' },
+ 'discriminator': 'type',
+ 'data': { 'linuxos': 'GuestLinuxCpuStats' } }
+
+##
+# @guest-get-cpustats:
+#
+# Retrieve information about CPU stats.
+# Returns: List of CPU stats of guest.
+#
+# Since: 7.1
+##
+{ 'command': 'guest-get-cpustats',
+ 'returns': ['GuestCpuStats']
+}
--
2.20.1
Looks good to me otherwise.
thanks
--
Marc-André Lureau