qga: add command 'guest-get-cpustats'

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.

Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: zhenwei pi <pizhenwei@bytedance.com>
Message-Id: <20220707005602.696557-3-pizhenwei@bytedance.com>
Reviewed-by: Konstantin Kostiuk <kkostiuk@redhat.com>
Signed-off-by: Konstantin Kostiuk <kkostiuk@redhat.com>

1 files changed, 81 insertions, 0 deletions

diff --git a/qga/qapi-schema.json b/qga/qapi-schema.json
index 9fa20e791b..869399ea1a 100644
--- a/qga/qapi-schema.json
+++ b/qga/qapi-schema.json
@@ -1576,3 +1576,84 @@
 { 'command': 'guest-get-diskstats',
   'returns': ['GuestDiskStatsInfo']
 }
+
+##
+# @GuestCpuStatsType:
+#
+# An enumeration of OS type
+#
+# Since: 7.1
+##
+{ 'enum': 'GuestCpuStatsType',
+  'data': [ 'linux' ] }
+
+
+##
+# @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': 'GuestCpuStatsType' },
+  'discriminator': 'type',
+  'data': { 'linux': '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']
+}