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1 # -*- Mode: Python -*-
2 # vim: filetype=python
3 #
4 # Copyright (c) 2022 Oracle and/or its affiliates.
5 #
6 # This work is licensed under the terms of the GNU GPL, version 2 or later.
7 # See the COPYING file in the top-level directory.
8 #
9 # SPDX-License-Identifier: GPL-2.0-or-later
10
11 ##
12 # **********
13 # Statistics
14 # **********
15 ##
16
17 ##
18 # @StatsType:
19 #
20 # Enumeration of statistics types
21 #
22 # @cumulative: stat is cumulative; value can only increase.
23 #
24 # @instant: stat is instantaneous; value can increase or decrease.
25 #
26 # @peak: stat is the peak value; value can only increase.
27 #
28 # @linear-histogram: stat is a linear histogram.
29 #
30 # @log2-histogram: stat is a logarithmic histogram, with one bucket
31 # for each power of two.
32 #
33 # Since: 7.1
34 ##
35 { 'enum' : 'StatsType',
36 'data' : [ 'cumulative', 'instant', 'peak', 'linear-histogram',
37 'log2-histogram' ] }
38
39 ##
40 # @StatsUnit:
41 #
42 # Enumeration of unit of measurement for statistics
43 #
44 # @bytes: stat reported in bytes.
45 #
46 # @seconds: stat reported in seconds.
47 #
48 # @cycles: stat reported in clock cycles.
49 #
50 # @boolean: stat is a boolean value.
51 #
52 # Since: 7.1
53 ##
54 { 'enum' : 'StatsUnit',
55 'data' : [ 'bytes', 'seconds', 'cycles', 'boolean' ] }
56
57 ##
58 # @StatsProvider:
59 #
60 # Enumeration of statistics providers.
61 #
62 # @kvm: since 7.1
63 #
64 # @cryptodev: since 8.0
65 #
66 # Since: 7.1
67 ##
68 { 'enum': 'StatsProvider',
69 'data': [ 'kvm', 'cryptodev' ] }
70
71 ##
72 # @StatsTarget:
73 #
74 # The kinds of objects on which one can request statistics.
75 #
76 # @vm: statistics that apply to the entire virtual machine or the
77 # entire QEMU process.
78 #
79 # @vcpu: statistics that apply to a single virtual CPU.
80 #
81 # @cryptodev: statistics that apply to a crypto device (since 8.0)
82 #
83 # Since: 7.1
84 ##
85 { 'enum': 'StatsTarget',
86 'data': [ 'vm', 'vcpu', 'cryptodev' ] }
87
88 ##
89 # @StatsRequest:
90 #
91 # Indicates a set of statistics that should be returned by
92 # `query-stats`.
93 #
94 # @provider: provider for which to return statistics.
95 #
96 # @names: statistics to be returned (all if omitted).
97 #
98 # Since: 7.1
99 ##
100 { 'struct': 'StatsRequest',
101 'data': { 'provider': 'StatsProvider',
102 '*names': [ 'str' ] } }
103
104 ##
105 # @StatsVCPUFilter:
106 #
107 # @vcpus: list of QOM paths for the desired vCPU objects.
108 #
109 # Since: 7.1
110 ##
111 { 'struct': 'StatsVCPUFilter',
112 'data': { '*vcpus': [ 'str' ] } }
113
114 ##
115 # @StatsFilter:
116 #
117 # The arguments to the `query-stats` command; specifies a target for
118 # which to request statistics and optionally the required subset of
119 # information for that target.
120 #
121 # @target: the kind of objects to query. Note that each possible
122 # target may enable additional filtering options
123 #
124 # @providers: which providers to request statistics from, and
125 # optionally which named values to return within each provider
126 #
127 # Since: 7.1
128 ##
129 { 'union': 'StatsFilter',
130 'base': {
131 'target': 'StatsTarget',
132 '*providers': [ 'StatsRequest' ] },
133 'discriminator': 'target',
134 'data': { 'vcpu': 'StatsVCPUFilter' } }
135
136 ##
137 # @StatsValue:
138 #
139 # @scalar: single unsigned 64-bit integers.
140 #
141 # @boolean: single boolean value.
142 #
143 # @list: list of unsigned 64-bit integers (used for histograms).
144 #
145 # Since: 7.1
146 ##
147 { 'alternate': 'StatsValue',
148 'data': { 'scalar': 'uint64',
149 'boolean': 'bool',
150 'list': [ 'uint64' ] } }
151
152 ##
153 # @Stats:
154 #
155 # @name: name of stat.
156 #
157 # @value: stat value.
158 #
159 # Since: 7.1
160 ##
161 { 'struct': 'Stats',
162 'data': { 'name': 'str',
163 'value' : 'StatsValue' } }
164
165 ##
166 # @StatsResult:
167 #
168 # @provider: provider for this set of statistics.
169 #
170 # @qom-path: Path to the object for which the statistics are returned,
171 # if the object is exposed in the QOM tree
172 #
173 # @stats: list of statistics.
174 #
175 # Since: 7.1
176 ##
177 { 'struct': 'StatsResult',
178 'data': { 'provider': 'StatsProvider',
179 '*qom-path': 'str',
180 'stats': [ 'Stats' ] } }
181
182 ##
183 # @query-stats:
184 #
185 # Return runtime-collected statistics for objects such as the VM or
186 # its vCPUs.
187 #
188 # The arguments are a `StatsFilter` and specify the provider and
189 # objects to return statistics about.
190 #
191 # Returns: a list of statistics, one for each provider and object
192 # (e.g., for each vCPU).
193 #
194 # Since: 7.1
195 ##
196 { 'command': 'query-stats',
197 'data': 'StatsFilter',
198 'boxed': true,
199 'returns': [ 'StatsResult' ] }
200
201 ##
202 # @StatsSchemaValue:
203 #
204 # Schema for a single statistic.
205 #
206 # @name: name of the statistic; each element of the schema is uniquely
207 # identified by a target, a provider (both available in
208 # `StatsSchema`) and the name.
209 #
210 # @type: kind of statistic.
211 #
212 # @unit: basic unit of measure for the statistic; if missing, the
213 # statistic is a simple number or counter.
214 #
215 # @base: base for the multiple of @unit in which the statistic is
216 # measured. Only present if @exponent is non-zero; @base and
217 # @exponent together form a SI prefix (e.g., _nano-_ for
218 # ``base=10`` and ``exponent=-9``) or IEC binary prefix (e.g.
219 # _kibi-_ for ``base=2`` and ``exponent=10``)
220 #
221 # @exponent: exponent for the multiple of @unit in which the statistic
222 # is expressed, or 0 for the basic unit
223 #
224 # @bucket-size: Present when @type is "linear-histogram", contains the
225 # width of each bucket of the histogram.
226 #
227 # Since: 7.1
228 ##
229 { 'struct': 'StatsSchemaValue',
230 'data': { 'name': 'str',
231 'type': 'StatsType',
232 '*unit': 'StatsUnit',
233 '*base': 'int8',
234 'exponent': 'int16',
235 '*bucket-size': 'uint32' } }
236
237 ##
238 # @StatsSchema:
239 #
240 # Schema for all available statistics for a provider and target.
241 #
242 # @provider: provider for this set of statistics.
243 #
244 # @target: the kind of object that can be queried through the
245 # provider.
246 #
247 # @stats: list of statistics.
248 #
249 # Since: 7.1
250 ##
251 { 'struct': 'StatsSchema',
252 'data': { 'provider': 'StatsProvider',
253 'target': 'StatsTarget',
254 'stats': [ 'StatsSchemaValue' ] } }
255
256 ##
257 # @query-stats-schemas:
258 #
259 # Return the schema for all available runtime-collected statistics.
260 #
261 # @provider: a provider to restrict the query to.
262 #
263 # .. note:: Runtime-collected statistics and their names fall outside
264 # QEMU's usual deprecation policies. QEMU will try to keep the set
265 # of available data stable, together with their names, but will not
266 # guarantee stability at all costs; the same is true of providers
267 # that source statistics externally, e.g. from Linux. For example,
268 # if the same value is being tracked with different names on
269 # different architectures or by different providers, one of them
270 # might be renamed. A statistic might go away if an algorithm is
271 # changed or some code is removed; changing a default might cause
272 # previously useful statistics to always report 0. Such changes,
273 # however, are expected to be rare.
274 #
275 # Since: 7.1
276 ##
277 { 'command': 'query-stats-schemas',
278 'data': { '*provider': 'StatsProvider' },
279 'returns': [ 'StatsSchema' ] }