1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * kvm_binary_stats_test
4  *
5  * Copyright (C) 2021, Google LLC.
6  *
7  * Test the fd-based interface for KVM statistics.
8  */
9 
10 #define _GNU_SOURCE /* for program_invocation_short_name */
11 #include <fcntl.h>
12 #include <stdio.h>
13 #include <stdlib.h>
14 #include <string.h>
15 #include <errno.h>
16 
17 #include "test_util.h"
18 
19 #include "kvm_util.h"
20 #include "asm/kvm.h"
21 #include "linux/kvm.h"
22 #include "kselftest.h"
23 
24 static void stats_test(int stats_fd)
25 {
26 	ssize_t ret;
27 	int i;
28 	size_t size_desc;
29 	size_t size_data = 0;
30 	struct kvm_stats_header header;
31 	char *id;
32 	struct kvm_stats_desc *stats_desc;
33 	u64 *stats_data;
34 	struct kvm_stats_desc *pdesc;
35 	u32 type, unit, base;
36 
37 	/* Read kvm stats header */
38 	read_stats_header(stats_fd, &header);
39 
40 	size_desc = get_stats_descriptor_size(&header);
41 
42 	/* Read kvm stats id string */
43 	id = malloc(header.name_size);
44 	TEST_ASSERT(id, "Allocate memory for id string");
45 
46 	ret = read(stats_fd, id, header.name_size);
47 	TEST_ASSERT(ret == header.name_size, "Read id string");
48 
49 	/* Check id string, that should start with "kvm" */
50 	TEST_ASSERT(!strncmp(id, "kvm", 3) && strlen(id) < header.name_size,
51 		    "Invalid KVM stats type, id: %s", id);
52 
53 	/* Sanity check for other fields in header */
54 	if (header.num_desc == 0) {
55 		ksft_print_msg("No KVM stats defined!\n");
56 		return;
57 	}
58 	/*
59 	 * The descriptor and data offsets must be valid, they must not overlap
60 	 * the header, and the descriptor and data blocks must not overlap each
61 	 * other.  Note, the data block is rechecked after its size is known.
62 	 */
63 	TEST_ASSERT(header.desc_offset && header.desc_offset >= sizeof(header) &&
64 		    header.data_offset && header.data_offset >= sizeof(header),
65 		    "Invalid offset fields in header");
66 
67 	TEST_ASSERT(header.desc_offset > header.data_offset ||
68 		    (header.desc_offset + size_desc * header.num_desc <= header.data_offset),
69 		    "Descriptor block is overlapped with data block");
70 
71 	/* Read kvm stats descriptors */
72 	stats_desc = read_stats_descriptors(stats_fd, &header);
73 
74 	/* Sanity check for fields in descriptors */
75 	for (i = 0; i < header.num_desc; ++i) {
76 		pdesc = get_stats_descriptor(stats_desc, i, &header);
77 		type = pdesc->flags & KVM_STATS_TYPE_MASK;
78 		unit = pdesc->flags & KVM_STATS_UNIT_MASK;
79 		base = pdesc->flags & KVM_STATS_BASE_MASK;
80 
81 		/* Check name string */
82 		TEST_ASSERT(strlen(pdesc->name) < header.name_size,
83 			    "KVM stats name (index: %d) too long", i);
84 
85 		/* Check type,unit,base boundaries */
86 		TEST_ASSERT(type <= KVM_STATS_TYPE_MAX,
87 			    "Unknown KVM stats (%s) type: %u", pdesc->name, type);
88 		TEST_ASSERT(unit <= KVM_STATS_UNIT_MAX,
89 			    "Unknown KVM stats (%s) unit: %u", pdesc->name, unit);
90 		TEST_ASSERT(base <= KVM_STATS_BASE_MAX,
91 			    "Unknown KVM stats (%s) base: %u", pdesc->name, base);
92 
93 		/*
94 		 * Check exponent for stats unit
95 		 * Exponent for counter should be greater than or equal to 0
96 		 * Exponent for unit bytes should be greater than or equal to 0
97 		 * Exponent for unit seconds should be less than or equal to 0
98 		 * Exponent for unit clock cycles should be greater than or
99 		 * equal to 0
100 		 * Exponent for unit boolean should be 0
101 		 */
102 		switch (pdesc->flags & KVM_STATS_UNIT_MASK) {
103 		case KVM_STATS_UNIT_NONE:
104 		case KVM_STATS_UNIT_BYTES:
105 		case KVM_STATS_UNIT_CYCLES:
106 			TEST_ASSERT(pdesc->exponent >= 0,
107 				    "Unsupported KVM stats (%s) exponent: %i",
108 				    pdesc->name, pdesc->exponent);
109 			break;
110 		case KVM_STATS_UNIT_SECONDS:
111 			TEST_ASSERT(pdesc->exponent <= 0,
112 				    "Unsupported KVM stats (%s) exponent: %i",
113 				    pdesc->name, pdesc->exponent);
114 			break;
115 		case KVM_STATS_UNIT_BOOLEAN:
116 			TEST_ASSERT(pdesc->exponent == 0,
117 				    "Unsupported KVM stats (%s) exponent: %d",
118 				    pdesc->name, pdesc->exponent);
119 			break;
120 		}
121 
122 		/* Check size field, which should not be zero */
123 		TEST_ASSERT(pdesc->size,
124 			    "KVM descriptor(%s) with size of 0", pdesc->name);
125 		/* Check bucket_size field */
126 		switch (pdesc->flags & KVM_STATS_TYPE_MASK) {
127 		case KVM_STATS_TYPE_LINEAR_HIST:
128 			TEST_ASSERT(pdesc->bucket_size,
129 				    "Bucket size of Linear Histogram stats (%s) is zero",
130 				    pdesc->name);
131 			break;
132 		default:
133 			TEST_ASSERT(!pdesc->bucket_size,
134 				    "Bucket size of stats (%s) is not zero",
135 				    pdesc->name);
136 		}
137 		size_data = max(size_data, pdesc->offset + pdesc->size * sizeof(*stats_data));
138 	}
139 
140 	/*
141 	 * Now that the size of the data block is known, verify the data block
142 	 * doesn't overlap the descriptor block.
143 	 */
144 	TEST_ASSERT(header.data_offset >= header.desc_offset ||
145 		    header.data_offset + size_data <= header.desc_offset,
146 		    "Data block is overlapped with Descriptor block");
147 
148 	/* Check validity of all stats data size */
149 	TEST_ASSERT(size_data >= header.num_desc * sizeof(*stats_data),
150 		    "Data size is not correct");
151 
152 	/* Allocate memory for stats data */
153 	stats_data = malloc(size_data);
154 	TEST_ASSERT(stats_data, "Allocate memory for stats data");
155 	/* Read kvm stats data as a bulk */
156 	ret = pread(stats_fd, stats_data, size_data, header.data_offset);
157 	TEST_ASSERT(ret == size_data, "Read KVM stats data");
158 	/* Read kvm stats data one by one */
159 	for (i = 0; i < header.num_desc; ++i) {
160 		pdesc = get_stats_descriptor(stats_desc, i, &header);
161 		read_stat_data(stats_fd, &header, pdesc, stats_data,
162 			       pdesc->size);
163 	}
164 
165 	free(stats_data);
166 	free(stats_desc);
167 	free(id);
168 }
169 
170 
171 static void vm_stats_test(struct kvm_vm *vm)
172 {
173 	int stats_fd = vm_get_stats_fd(vm);
174 
175 	stats_test(stats_fd);
176 	close(stats_fd);
177 	TEST_ASSERT(fcntl(stats_fd, F_GETFD) == -1, "Stats fd not freed");
178 }
179 
180 static void vcpu_stats_test(struct kvm_vcpu *vcpu)
181 {
182 	int stats_fd = vcpu_get_stats_fd(vcpu);
183 
184 	stats_test(stats_fd);
185 	close(stats_fd);
186 	TEST_ASSERT(fcntl(stats_fd, F_GETFD) == -1, "Stats fd not freed");
187 }
188 
189 #define DEFAULT_NUM_VM		4
190 #define DEFAULT_NUM_VCPU	4
191 
192 /*
193  * Usage: kvm_bin_form_stats [#vm] [#vcpu]
194  * The first parameter #vm set the number of VMs being created.
195  * The second parameter #vcpu set the number of VCPUs being created.
196  * By default, DEFAULT_NUM_VM VM and DEFAULT_NUM_VCPU VCPU for the VM would be
197  * created for testing.
198  */
199 
200 int main(int argc, char *argv[])
201 {
202 	int i, j;
203 	struct kvm_vcpu **vcpus;
204 	struct kvm_vm **vms;
205 	int max_vm = DEFAULT_NUM_VM;
206 	int max_vcpu = DEFAULT_NUM_VCPU;
207 
208 	/* Get the number of VMs and VCPUs that would be created for testing. */
209 	if (argc > 1) {
210 		max_vm = strtol(argv[1], NULL, 0);
211 		if (max_vm <= 0)
212 			max_vm = DEFAULT_NUM_VM;
213 	}
214 	if (argc > 2) {
215 		max_vcpu = strtol(argv[2], NULL, 0);
216 		if (max_vcpu <= 0)
217 			max_vcpu = DEFAULT_NUM_VCPU;
218 	}
219 
220 	ksft_print_header();
221 
222 	/* Check the extension for binary stats */
223 	TEST_REQUIRE(kvm_has_cap(KVM_CAP_BINARY_STATS_FD));
224 
225 	ksft_set_plan(max_vm);
226 
227 	/* Create VMs and VCPUs */
228 	vms = malloc(sizeof(vms[0]) * max_vm);
229 	TEST_ASSERT(vms, "Allocate memory for storing VM pointers");
230 
231 	vcpus = malloc(sizeof(struct kvm_vcpu *) * max_vm * max_vcpu);
232 	TEST_ASSERT(vcpus, "Allocate memory for storing vCPU pointers");
233 
234 	for (i = 0; i < max_vm; ++i) {
235 		vms[i] = vm_create_barebones();
236 		for (j = 0; j < max_vcpu; ++j)
237 			vcpus[i * max_vcpu + j] = __vm_vcpu_add(vms[i], j);
238 	}
239 
240 	/* Check stats read for every VM and VCPU */
241 	for (i = 0; i < max_vm; ++i) {
242 		vm_stats_test(vms[i]);
243 		for (j = 0; j < max_vcpu; ++j)
244 			vcpu_stats_test(vcpus[i * max_vcpu + j]);
245 		ksft_test_result_pass("vm%i\n", i);
246 	}
247 
248 	for (i = 0; i < max_vm; ++i)
249 		kvm_vm_free(vms[i]);
250 	free(vms);
251 
252 	ksft_finished();	/* Print results and exit() accordingly */
253 }
254