xref: /linux/tools/testing/selftests/kvm/lib/test_util.c (revision 7f9039c524a351c684149ecf1b3c5145a0dff2fe)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * tools/testing/selftests/kvm/lib/test_util.c
4  *
5  * Copyright (C) 2020, Google LLC.
6  */
7 #include <stdio.h>
8 #include <stdarg.h>
9 #include <assert.h>
10 #include <ctype.h>
11 #include <limits.h>
12 #include <stdlib.h>
13 #include <time.h>
14 #include <sys/stat.h>
15 #include <sys/syscall.h>
16 #include <linux/mman.h>
17 #include "linux/kernel.h"
18 
19 #include "test_util.h"
20 
21 /*
22  * Random number generator that is usable from guest code. This is the
23  * Park-Miller LCG using standard constants.
24  */
25 
26 struct guest_random_state new_guest_random_state(uint32_t seed)
27 {
28 	struct guest_random_state s = {.seed = seed};
29 	return s;
30 }
31 
32 uint32_t guest_random_u32(struct guest_random_state *state)
33 {
34 	state->seed = (uint64_t)state->seed * 48271 % ((uint32_t)(1 << 31) - 1);
35 	return state->seed;
36 }
37 
38 /*
39  * Parses "[0-9]+[kmgt]?".
40  */
41 size_t parse_size(const char *size)
42 {
43 	size_t base;
44 	char *scale;
45 	int shift = 0;
46 
47 	TEST_ASSERT(size && isdigit(size[0]), "Need at least one digit in '%s'", size);
48 
49 	base = strtoull(size, &scale, 0);
50 
51 	TEST_ASSERT(base != ULLONG_MAX, "Overflow parsing size!");
52 
53 	switch (tolower(*scale)) {
54 	case 't':
55 		shift = 40;
56 		break;
57 	case 'g':
58 		shift = 30;
59 		break;
60 	case 'm':
61 		shift = 20;
62 		break;
63 	case 'k':
64 		shift = 10;
65 		break;
66 	case 'b':
67 	case '\0':
68 		shift = 0;
69 		break;
70 	default:
71 		TEST_ASSERT(false, "Unknown size letter %c", *scale);
72 	}
73 
74 	TEST_ASSERT((base << shift) >> shift == base, "Overflow scaling size!");
75 
76 	return base << shift;
77 }
78 
79 int64_t timespec_to_ns(struct timespec ts)
80 {
81 	return (int64_t)ts.tv_nsec + 1000000000LL * (int64_t)ts.tv_sec;
82 }
83 
84 struct timespec timespec_add_ns(struct timespec ts, int64_t ns)
85 {
86 	struct timespec res;
87 
88 	res.tv_nsec = ts.tv_nsec + ns;
89 	res.tv_sec = ts.tv_sec + res.tv_nsec / 1000000000LL;
90 	res.tv_nsec %= 1000000000LL;
91 
92 	return res;
93 }
94 
95 struct timespec timespec_add(struct timespec ts1, struct timespec ts2)
96 {
97 	int64_t ns1 = timespec_to_ns(ts1);
98 	int64_t ns2 = timespec_to_ns(ts2);
99 	return timespec_add_ns((struct timespec){0}, ns1 + ns2);
100 }
101 
102 struct timespec timespec_sub(struct timespec ts1, struct timespec ts2)
103 {
104 	int64_t ns1 = timespec_to_ns(ts1);
105 	int64_t ns2 = timespec_to_ns(ts2);
106 	return timespec_add_ns((struct timespec){0}, ns1 - ns2);
107 }
108 
109 struct timespec timespec_elapsed(struct timespec start)
110 {
111 	struct timespec end;
112 
113 	clock_gettime(CLOCK_MONOTONIC, &end);
114 	return timespec_sub(end, start);
115 }
116 
117 struct timespec timespec_div(struct timespec ts, int divisor)
118 {
119 	int64_t ns = timespec_to_ns(ts) / divisor;
120 
121 	return timespec_add_ns((struct timespec){0}, ns);
122 }
123 
124 void print_skip(const char *fmt, ...)
125 {
126 	va_list ap;
127 
128 	assert(fmt);
129 	va_start(ap, fmt);
130 	vprintf(fmt, ap);
131 	va_end(ap);
132 	puts(", skipping test");
133 }
134 
135 static bool test_sysfs_path(const char *path)
136 {
137 	struct stat statbuf;
138 	int ret;
139 
140 	ret = stat(path, &statbuf);
141 	TEST_ASSERT(ret == 0 || (ret == -1 && errno == ENOENT),
142 		    "Error in stat()ing '%s'", path);
143 
144 	return ret == 0;
145 }
146 
147 bool thp_configured(void)
148 {
149 	return test_sysfs_path("/sys/kernel/mm/transparent_hugepage");
150 }
151 
152 static size_t get_sysfs_val(const char *path)
153 {
154 	size_t size;
155 	FILE *f;
156 	int ret;
157 
158 	f = fopen(path, "r");
159 	TEST_ASSERT(f, "Error opening '%s'", path);
160 
161 	ret = fscanf(f, "%ld", &size);
162 	TEST_ASSERT(ret > 0, "Error reading '%s'", path);
163 
164 	/* Re-scan the input stream to verify the entire file was read. */
165 	ret = fscanf(f, "%ld", &size);
166 	TEST_ASSERT(ret < 1, "Error reading '%s'", path);
167 
168 	fclose(f);
169 	return size;
170 }
171 
172 size_t get_trans_hugepagesz(void)
173 {
174 	TEST_ASSERT(thp_configured(), "THP is not configured in host kernel");
175 
176 	return get_sysfs_val("/sys/kernel/mm/transparent_hugepage/hpage_pmd_size");
177 }
178 
179 bool is_numa_balancing_enabled(void)
180 {
181 	if (!test_sysfs_path("/proc/sys/kernel/numa_balancing"))
182 		return false;
183 	return get_sysfs_val("/proc/sys/kernel/numa_balancing") == 1;
184 }
185 
186 size_t get_def_hugetlb_pagesz(void)
187 {
188 	char buf[64];
189 	const char *hugepagesize = "Hugepagesize:";
190 	const char *hugepages_total = "HugePages_Total:";
191 	FILE *f;
192 
193 	f = fopen("/proc/meminfo", "r");
194 	TEST_ASSERT(f != NULL, "Error in opening /proc/meminfo");
195 
196 	while (fgets(buf, sizeof(buf), f) != NULL) {
197 		if (strstr(buf, hugepages_total) == buf) {
198 			unsigned long long total = strtoull(buf + strlen(hugepages_total), NULL, 10);
199 			if (!total) {
200 				fprintf(stderr, "HUGETLB is not enabled in /proc/sys/vm/nr_hugepages\n");
201 				exit(KSFT_SKIP);
202 			}
203 		}
204 		if (strstr(buf, hugepagesize) == buf) {
205 			fclose(f);
206 			return strtoull(buf + strlen(hugepagesize), NULL, 10) << 10;
207 		}
208 	}
209 
210 	if (feof(f)) {
211 		fprintf(stderr, "HUGETLB is not configured in host kernel");
212 		exit(KSFT_SKIP);
213 	}
214 
215 	TEST_FAIL("Error in reading /proc/meminfo");
216 }
217 
218 #define ANON_FLAGS	(MAP_PRIVATE | MAP_ANONYMOUS)
219 #define ANON_HUGE_FLAGS	(ANON_FLAGS | MAP_HUGETLB)
220 
221 const struct vm_mem_backing_src_alias *vm_mem_backing_src_alias(uint32_t i)
222 {
223 	static const struct vm_mem_backing_src_alias aliases[] = {
224 		[VM_MEM_SRC_ANONYMOUS] = {
225 			.name = "anonymous",
226 			.flag = ANON_FLAGS,
227 		},
228 		[VM_MEM_SRC_ANONYMOUS_THP] = {
229 			.name = "anonymous_thp",
230 			.flag = ANON_FLAGS,
231 		},
232 		[VM_MEM_SRC_ANONYMOUS_HUGETLB] = {
233 			.name = "anonymous_hugetlb",
234 			.flag = ANON_HUGE_FLAGS,
235 		},
236 		[VM_MEM_SRC_ANONYMOUS_HUGETLB_16KB] = {
237 			.name = "anonymous_hugetlb_16kb",
238 			.flag = ANON_HUGE_FLAGS | MAP_HUGE_16KB,
239 		},
240 		[VM_MEM_SRC_ANONYMOUS_HUGETLB_64KB] = {
241 			.name = "anonymous_hugetlb_64kb",
242 			.flag = ANON_HUGE_FLAGS | MAP_HUGE_64KB,
243 		},
244 		[VM_MEM_SRC_ANONYMOUS_HUGETLB_512KB] = {
245 			.name = "anonymous_hugetlb_512kb",
246 			.flag = ANON_HUGE_FLAGS | MAP_HUGE_512KB,
247 		},
248 		[VM_MEM_SRC_ANONYMOUS_HUGETLB_1MB] = {
249 			.name = "anonymous_hugetlb_1mb",
250 			.flag = ANON_HUGE_FLAGS | MAP_HUGE_1MB,
251 		},
252 		[VM_MEM_SRC_ANONYMOUS_HUGETLB_2MB] = {
253 			.name = "anonymous_hugetlb_2mb",
254 			.flag = ANON_HUGE_FLAGS | MAP_HUGE_2MB,
255 		},
256 		[VM_MEM_SRC_ANONYMOUS_HUGETLB_8MB] = {
257 			.name = "anonymous_hugetlb_8mb",
258 			.flag = ANON_HUGE_FLAGS | MAP_HUGE_8MB,
259 		},
260 		[VM_MEM_SRC_ANONYMOUS_HUGETLB_16MB] = {
261 			.name = "anonymous_hugetlb_16mb",
262 			.flag = ANON_HUGE_FLAGS | MAP_HUGE_16MB,
263 		},
264 		[VM_MEM_SRC_ANONYMOUS_HUGETLB_32MB] = {
265 			.name = "anonymous_hugetlb_32mb",
266 			.flag = ANON_HUGE_FLAGS | MAP_HUGE_32MB,
267 		},
268 		[VM_MEM_SRC_ANONYMOUS_HUGETLB_256MB] = {
269 			.name = "anonymous_hugetlb_256mb",
270 			.flag = ANON_HUGE_FLAGS | MAP_HUGE_256MB,
271 		},
272 		[VM_MEM_SRC_ANONYMOUS_HUGETLB_512MB] = {
273 			.name = "anonymous_hugetlb_512mb",
274 			.flag = ANON_HUGE_FLAGS | MAP_HUGE_512MB,
275 		},
276 		[VM_MEM_SRC_ANONYMOUS_HUGETLB_1GB] = {
277 			.name = "anonymous_hugetlb_1gb",
278 			.flag = ANON_HUGE_FLAGS | MAP_HUGE_1GB,
279 		},
280 		[VM_MEM_SRC_ANONYMOUS_HUGETLB_2GB] = {
281 			.name = "anonymous_hugetlb_2gb",
282 			.flag = ANON_HUGE_FLAGS | MAP_HUGE_2GB,
283 		},
284 		[VM_MEM_SRC_ANONYMOUS_HUGETLB_16GB] = {
285 			.name = "anonymous_hugetlb_16gb",
286 			.flag = ANON_HUGE_FLAGS | MAP_HUGE_16GB,
287 		},
288 		[VM_MEM_SRC_SHMEM] = {
289 			.name = "shmem",
290 			.flag = MAP_SHARED,
291 		},
292 		[VM_MEM_SRC_SHARED_HUGETLB] = {
293 			.name = "shared_hugetlb",
294 			/*
295 			 * No MAP_HUGETLB, we use MFD_HUGETLB instead. Since
296 			 * we're using "file backed" memory, we need to specify
297 			 * this when the FD is created, not when the area is
298 			 * mapped.
299 			 */
300 			.flag = MAP_SHARED,
301 		},
302 	};
303 	_Static_assert(ARRAY_SIZE(aliases) == NUM_SRC_TYPES,
304 		       "Missing new backing src types?");
305 
306 	TEST_ASSERT(i < NUM_SRC_TYPES, "Backing src type ID %d too big", i);
307 
308 	return &aliases[i];
309 }
310 
311 #define MAP_HUGE_PAGE_SIZE(x) (1ULL << ((x >> MAP_HUGE_SHIFT) & MAP_HUGE_MASK))
312 
313 size_t get_backing_src_pagesz(uint32_t i)
314 {
315 	uint32_t flag = vm_mem_backing_src_alias(i)->flag;
316 
317 	switch (i) {
318 	case VM_MEM_SRC_ANONYMOUS:
319 	case VM_MEM_SRC_SHMEM:
320 		return getpagesize();
321 	case VM_MEM_SRC_ANONYMOUS_THP:
322 		return get_trans_hugepagesz();
323 	case VM_MEM_SRC_ANONYMOUS_HUGETLB:
324 	case VM_MEM_SRC_SHARED_HUGETLB:
325 		return get_def_hugetlb_pagesz();
326 	default:
327 		return MAP_HUGE_PAGE_SIZE(flag);
328 	}
329 }
330 
331 bool is_backing_src_hugetlb(uint32_t i)
332 {
333 	return !!(vm_mem_backing_src_alias(i)->flag & MAP_HUGETLB);
334 }
335 
336 static void print_available_backing_src_types(const char *prefix)
337 {
338 	int i;
339 
340 	printf("%sAvailable backing src types:\n", prefix);
341 
342 	for (i = 0; i < NUM_SRC_TYPES; i++)
343 		printf("%s    %s\n", prefix, vm_mem_backing_src_alias(i)->name);
344 }
345 
346 void backing_src_help(const char *flag)
347 {
348 	printf(" %s: specify the type of memory that should be used to\n"
349 	       "     back the guest data region. (default: %s)\n",
350 	       flag, vm_mem_backing_src_alias(DEFAULT_VM_MEM_SRC)->name);
351 	print_available_backing_src_types("     ");
352 }
353 
354 enum vm_mem_backing_src_type parse_backing_src_type(const char *type_name)
355 {
356 	int i;
357 
358 	for (i = 0; i < NUM_SRC_TYPES; i++)
359 		if (!strcmp(type_name, vm_mem_backing_src_alias(i)->name))
360 			return i;
361 
362 	print_available_backing_src_types("");
363 	TEST_FAIL("Unknown backing src type: %s", type_name);
364 	return -1;
365 }
366 
367 long get_run_delay(void)
368 {
369 	char path[64];
370 	long val[2];
371 	FILE *fp;
372 
373 	sprintf(path, "/proc/%ld/schedstat", syscall(SYS_gettid));
374 	fp = fopen(path, "r");
375 	/* Return MIN_RUN_DELAY_NS upon failure just to be safe */
376 	if (fscanf(fp, "%ld %ld ", &val[0], &val[1]) < 2)
377 		val[1] = MIN_RUN_DELAY_NS;
378 	fclose(fp);
379 
380 	return val[1];
381 }
382 
383 int atoi_paranoid(const char *num_str)
384 {
385 	char *end_ptr;
386 	long num;
387 
388 	errno = 0;
389 	num = strtol(num_str, &end_ptr, 0);
390 	TEST_ASSERT(!errno, "strtol(\"%s\") failed", num_str);
391 	TEST_ASSERT(num_str != end_ptr,
392 		    "strtol(\"%s\") didn't find a valid integer.", num_str);
393 	TEST_ASSERT(*end_ptr == '\0',
394 		    "strtol(\"%s\") failed to parse trailing characters \"%s\".",
395 		    num_str, end_ptr);
396 	TEST_ASSERT(num >= INT_MIN && num <= INT_MAX,
397 		    "%ld not in range of [%d, %d]", num, INT_MIN, INT_MAX);
398 
399 	return num;
400 }
401 
402 char *strdup_printf(const char *fmt, ...)
403 {
404 	va_list ap;
405 	char *str;
406 
407 	va_start(ap, fmt);
408 	TEST_ASSERT(vasprintf(&str, fmt, ap) >= 0, "vasprintf() failed");
409 	va_end(ap);
410 
411 	return str;
412 }
413 
414 #define CLOCKSOURCE_PATH "/sys/devices/system/clocksource/clocksource0/current_clocksource"
415 
416 char *sys_get_cur_clocksource(void)
417 {
418 	char *clk_name;
419 	struct stat st;
420 	FILE *fp;
421 
422 	fp = fopen(CLOCKSOURCE_PATH, "r");
423 	TEST_ASSERT(fp, "failed to open clocksource file, errno: %d", errno);
424 
425 	TEST_ASSERT(!fstat(fileno(fp), &st), "failed to stat clocksource file, errno: %d",
426 		    errno);
427 
428 	clk_name = malloc(st.st_size);
429 	TEST_ASSERT(clk_name, "failed to allocate buffer to read file");
430 
431 	TEST_ASSERT(fgets(clk_name, st.st_size, fp), "failed to read clocksource file: %d",
432 		    ferror(fp));
433 
434 	fclose(fp);
435 
436 	return clk_name;
437 }
438